Incineration of Municipal SolidWaste

www.defra.gov.uk

Contents

Preamble 1

1. Introduction 2

2. How it works 5

3. Markets and outlets for the outputs 13

4. Track record 15

5. Contractual and financing issues 18

6. Planning and permitting issues 20

7. Social and perception issues 27

8. Cost 28

9. Contribution to national targets 29

10. Further reading and sources of information 31

11. Glossary 32

Prepared by Enviros Consulting Limited on behalf of Defra as part of the New Technologies Supporter Programme.

We acknowledge support from the Department for Environment, Food & Rural Affairs (Defra), the Department ofCommunities & Local Government (DCLG), the Environment Agency (EA) and BeEnvironmental Ltd.

This Document has been produced by Enviros Consulting Limited (Technical Advisors) on behalf of Defra to provideassistance to Local Authorities and the waste management market generally through awareness raising of the keymunicipal waste management options for thediversion of BMW from landfill. The Document has been developed ingood faith by the Advisors on behalf of Defra, and neither Defra not its Advisers shall incur any liability for any actionor omission arising out of any reliance being placed on the Document by any Local Authority or organisation or otherperson. Any Local Authority or organisation or other person in receipt of this Document should take their own legal,financial and other relevant professional advice when considering what action (if any) to take in respect of any wastestrategy, initiative, proposal, or other involvement with any waste management option or technology, or beforeplacing any reliance on anything contained therein.

Any interpretation of policy in this document is that of Enviros and not of Defra or DCLG.

Crown copyright, 2007

Cover image courtesy of Project Integra, Hampshire

Preamble

This Waste Management Technology Brief,updated in 2007, is one of a series ofdocuments prepared under the NewTechnologies work stream of the Defra WasteImplementation Programme. The Briefsaddress technologies that may have anincreasing role in diverting Municipal SolidWaste (MSW) from landfill. They provide analternative technical option as part of anintegrated waste strategy, having thepotential to recover materials & energy andreduce the quantity of MSW requiring finaldisposal to landfill.

This Brief has been produced to provide anoverview of Incineration Technology, whichrecovers energy from the combustion ofMSW. Although not a new technology it canpotentially form part of an overall integratedwaste management strategy to divert MSWfrom landfill. Other titles in this seriesinclude: An Introductory Guide to WasteManagement Options, Advanced BiologicalTreatment, Mechanical Biological Treatment,Mechanical Heat Treatment, AdvancedThermal Treatment, Renewable Energy andWaste Technologies, and Managing Outputsfrom Waste Technologies.

These waste technologies can assist in thedelivery of the Government’s key objectives,as outlined in The Waste Strategy for England2007, for meeting and exceeding the LandfillDirective diversion targets, and increasingrecycling of resources and recovery of energy.

The prime audience for these Briefs are localauthorities, in particular waste managementofficers, members and other key decisionmakers for MSW management in England. Itshould be noted that these documents areintended as guides to each generictechnology area. Further information can befound at the Waste Technology Data Centre,

funded by the Defra New TechnologiesProgramme and delivered by theEnvironment Agency (www.environment-agency.gov.uk/wtd). These Briefs dealprimarily with the treatment and processingof residual MSW. Information on thecollection and markets for source segregatedmaterials is available from Defra and fromROTATE (Recycling and Organics TechnicalAdvisory Team) at the Waste & ResourcesAction Programme (WRAP).

The Defra New Technologies DemonstratorProgramme has provided nine projects aimedat proving the economic, social andenvironmental viability (or not) of a selectionof waste management technologies. Forinformation on the demonstrator projects seethe Defra website or emailWastetech@enviros.com.

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1. Introduction

Municipal Solid Waste (MSW) is wastecollected by or on behalf of a local authority.It comprises mostly household waste and itmay include some commercial and industrialwastes. Historically, nationally the quantity ofMSW has risen year on year1, presenting agrowing problem for local authoritiesparticularly as legislation, now limits (byimplication2) the amount of mixed MSW thatcan be sent to landfill, comes into effect,becomes more stringent over time.

One of the guiding principles for Europeanand UK waste management has been theconcept of a hierarchy of waste managementoptions, where the most desirable option isnot to produce the waste in the first place(waste prevention) and the least desirableoption is to dispose of the waste with norecovery of either materials and/or energy.Between these two extremes there are a widevariety of waste treatment options that maybe used as part of a waste managementstrategy to recover materials (for examplefurniture reuse, glass recycling or organicwaste composting) or generate energy fromthe wastes (for example through incineration,or digesting biodegradable wastes to produceusable gases).

At present more than 62% of all MSWgenerated in England is disposed of inlandfills3. However, European and UKlegislation has been put in place to limit theamount of biodegradable municipal waste(BMW) sent for disposal in landfills4. A keydriver for this focus on biodegradable wasteis to reduce the uncontrolled release ofgreenhouse gas emissions to atmosphere. TheLandfill Directive also requires waste to bepre-treated prior to disposal. The diversion ofthis material is one of the most significant

challenges facing the management ofMunicipal Solid Waste in the UK.

The new technologies that are available forresidual MSW treatment can be split intothree main categories:

• Mechanical and Biological Treatment (MBT)

• Mechanical Heat Treatment (MHT)

• Advanced Thermal Treatment (ATT) –principally gasification and pyrolysis

In addition to these, incineration offers afurther option for the treatment of residualMSW and is an already proven and bankable(large scale facilities already in operation)technology in the UK.

Throughout this document, the term‘incineration’ is used to describe processesthat combust waste and recover energy.Sometimes others use the term energy fromwaste or direct combustion to describeincineration. All municipal waste incineratorsin the UK recover energy from waste in theform of electricity and/or heat generation(see Box 1). Energy recovery can also beachieved from different methods ofmanaging waste including:

• ATT - production of electricity and/or heatby the thermal treatment decomposition ofthe waste and subsequent use of thesecondary products (typically syngas)

• Anaerobic digestion – production of energyfrom the combustion of the biogas which isproduced from the digestion ofbiodegradable waste

• Landfill - production of electricity from thecombustion of landfill gas produced asbiodegradable waste decomposes.

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1 This is now showing signs of slowing down and in some areas waste arisings are falling, and indeed in 2005/6 there was a 3% fall nationally.However, this may be partly explained by other factors occurring in that particular financial year.

2 Targets pertain to the biodegradable fraction in MSW3 Results from WasteDataFlow http://www.defra.gov.uk/environment/statistics/wastats/bulletin.htm4 The Landfill Directive, Waste and Emissions Trading Act 2003 and Landfill Allowances Trading Scheme Regulations

Main Heading

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2. How it works

Combustion of MSW results in the release ofcarbon dioxide (and other greenhouse gases).Part of the MSW is biomass derived materiale.g. card, paper, timber which is a source ofrenewable energy. MSW also containscombustible elements which are fossil fuelderived materials e.g. plastics and aretherefore not a source of renewable energy.Fossil fuel-based carbon dioxide contributessignificantly towards the greenhouse effectand hence global warming. In the context ofsustainable energy generation carbon emittedfrom biodegradable waste is classed as short-cycle carbon (i.e. the amount given off whencombusted equates to that absorbed duringits lifetime).

The more efficient the energy generationprocess, e.g. CHP, the lower the carbonemissions are per unit of energy producedand the greater the energy and carbonbenefits. Hence when considering energyrecovery, carbon emissions need to beconsidered in terms of composition of theresidual waste stream, the type of energyproduced (heat and/or power) and the overallgenerating efficiency of the facility. Thegrowing importance of climate change meansthe carbon footprint of waste managementneeds to be fully considered in selectingtechnologies. The Environment Agencylifecycle tool (Waste and ResourcesAssessment Tool for the Environment –WRATE) is aimed at assisting the comparisonand assessment of the environmentalperformance of different waste options. Formore information see http://www.environment-agency.gov.uk/wtd/1396237/?version=1&lang=_e

1. Introduction

Box 1 – Energy Generation

Energy recovered from waste can be usedin the following ways:

• Generation of Power (electricity)

• Generation of Heat

• Generation of Heat and Power (this isreferred to as Combined Heat andPower (CHP)

The energy generation option selected foran incineration facility will depend on thepotential for end users to utilise the heatand/or power available. In most instancespower can be easily distributed and soldvia the national grid and this is by far themost common form of energy recovery.

For heat, the consumer needs to be localto the facility producing the heat and adedicated distribution system (network) isrequired. Unless all of the available heatcan be used the generating facility will notalways be operating at its optimumefficiency.

The use of CHP combines the generationof heat and power (electricity). This helpsto increase the overall energy efficiency fora facility compared to generating poweronly. In addition, as power and heatdemand varies a CHP plant can bedesigned to meet this variation and hencemaintain optimum levels of efficiency.

1. Introduction

4

The purpose of this document is to provide anoverview of incineration with energyrecovery. This will include information ontechnologies, UK and European experience,regulatory issues, public perception and socialissues and outputs compared to othertreatment options listed above.

There are a wide variety of alternative wastemanagement options and strategies availablefor dealing with MSW to limit the residualamount left for disposal to landfill. This

guide is designed to be read in conjunctionwith the other Waste ManagementTechnology Briefs in this series and with thecase studies provided on Waste TechnologyData Centre. Further details aboutincineration and new technologies for MSWfeatured in this report are available from theWaste Technology Data Centrehttp://www.environment-agency.gov.uk/wtd.Other relevant sources of information areidentified throughout the document.

Cover image courtesy of Project Integra, Hampshire

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2. How it works

2.1 Incineration and the Waste Hierarchy

The waste hierarchy sets out the broadoptions for waste management, with energyrecovery from waste being a preferred optionto landfill. However, it recognises that priorto energy recovery waste reduction, re-use,recycling and composting are preferred,where appropriate. European experienceillustrates that recovery of energy fromresidual waste (including by incineration) iscompatible with high recycling rates.Therefore, both incineration and ATT canform part of an overall waste managementstrategy but not at the expense of wastereduction or recycling.

The key to striking the right balance lies inearly consultation between stakeholderswhen local waste strategies are beingdeveloped, and in suitably flexible facilitiesand contracts – i.e. that do not ‘lock in’ fixedamounts of waste should recycling ratesincrease. In addition, the commercialdeliverability of a facility needs to beconsidered when determining capacitiesrequired and contract periods. In mainlandEurope, Denmark and the Netherlands divertthe most waste from landfill, achieving thehighest recycling rates but have a highreliance on incineration to deal with residualwaste. Scandinavian countries in particularhave a greater acceptance of incineration andthe role it plays in delivering renewable,district electricity and heating. In the EU,Austria and Belgium have the highestrecycling and incineration rates.

2.2 Waste Incineration Directive (WID)

In the UK, all waste incineration plant mustcomply with the WID. This Directive sets the

most stringent emissions controls for anythermal processes regulated in the EU. Theobjectives of the WID Directive are tominimise the impact from emissions to air,soil, surface and ground water on theenvironment and human health resultingfrom the incineration and co-incineration ofwaste.

At a European level, the Waste IncinerationDirective5 incorporates and extends therequirements of the 1989 Municipal WasteIncineration (MWI) Directives6 and theHazardous Waste Incineration Directive7. WIDforms a single Directive on waste incinerationand has repealed those three Directives sincelate 2005.

The requirements of the Directive have beentranslated into the UK through The WasteIncineration (England and Wales) Regulations20028 which came into force on 28 December2002. The enforcement of the WID isthrough the Pollution Prevention and Control(PPC) regime, which provides the mechanismby which all major industrial processes arepermitted and regulated, with respect totheir environmental performance.

The key requirements in the WID for theoperation of an incineration plant are asfollows:

• a minimum combustion temperature andresidence time of the resulting combustionproducts. For MSW this is a minimumrequirement of 850oC for 2 seconds

• specific emission limits for the release toatmosphere of the following:

- Sulphur Dioxide (SO2)

5 Waste Incineration Directive 2000/76/EC of the European Parliament and of the Council of 4 December 2000 on the incineration of waste.http://eur-lex.europa.eu/LexUriServ/site/en/consleg/2000/L/02000L0076-20001228-en.pdf

6 Municipal Waste Incineration (MWI) Directives (89/429/EEC and 89/369/EEC)7 Hazardous Waste Incineration Directive (94/67/EC).8 The Waste Incineration (England and Wales) Regulations 2002 (SI 2002 No, 2980). See http://www.opsi.gov.uk/si/si2002/20022980.htm

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- Nitrogen Oxides (NOx)

- Hydrogen Chloride (HCl)

- Volatile Organic Compounds (VOCs)

- Carbon Monoxide (CO)

- Particulate (fly ash)

- Heavy Metals

- Dioxins

- a requirement that the resulting bottomash that is produced has a total organiccarbon content of less than 3%.

The combustion conditions are required toensure complete burnout of the waste isachieved. Emission limits to atmosphere areset to minimise environmental and healthimpacts. The carbon content in the ashrepresents minimisation of the combustiblematerial and destruction of the waste.

Further information on environmentalcompliance for incineration plant can beobtained from the Integrated PollutionPrevention and Control Reference Documenton the Best Available Techniques for WasteIncineration, published by the EuropeanCommission in August 2006. This documentcan be accessed via the weblink below.

http://eippcb.jrc.es/pages/BActivities.cfm

2.3 Difference between Incineration &Advanced Thermal Treatment

Both Incineration and Advanced ThermalTreatment (ATT) technologies offer the optionof treating residual waste and recoveringenergy. These technologies are different inhow the waste is processed and the energyliberated for recovery, i.e. combustion directlyreleases the energy in the waste, whereaspyrolysis and gasification thermally treat thewaste to generate secondary products (gas,liquid and/or solid) from which energy can begenerated.

The main technical differences betweenIncineration and ATT are presented below. Inaddition, Figure 1 shows how the pyrolysisand gasification process differs fromincineration (direct combustion) in terms ofthe levels of air present.

Incineration

Incineration involves the combustion oftypically unprepared (raw or residual) MSW.To allow the combustion to take place asufficient quantity of oxygen is required tofully oxidise the fuel. Incineration plantcombustion temperatures are in excess of850oC and the waste is mostly converted intocarbon dioxide and water and any non-combustible materials (e.g. metals, glass,stones) remain as a solid, known asIncinerator Bottom Ash (IBA) that alwayscontains a small amount of residual carbon.The direct combustion of a waste usuallyreleases more of the available energycompared to pyrolysis and gasification.

Advanced Thermal Treatment - Pyrolysis

In contrast to combustion, pyrolysis is thethermal degradation of a substance in theabsence of oxygen. This process requires anexternal heat source to maintain the pyrolysisprocess. Typically, temperatures of between300oC to 850oC are used during pyrolysis ofmaterials such as MSW. The productsproduced from pyrolysing materials are asolid residue and syngas. The solid residue(sometimes described as a char) is acombination of non-combustible materialsand carbon. The syngas is a mixture of gases(combustible constituents include carbonmonoxide, hydrogen and methane) andcondensable oils, waxes and tars. The syngastypically has a net calorific value (NCV) ofbetween 10 and 20 MJ/Nm3. If required, thecondensable (liquid) fraction can be collected,potentially for use as a liquid fuel or a

2. How it works

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2. How it works

Figure 1: Levels of Air (Oxygen) Present During Pyrolysis, Gasification and Combustion Processes for MSW

Pyrolysis Gasification incineration

Increasing air supply

Absenceof air Excess air

Theoretical(stoichiometric) air

required tocombust the fuel

No air Partial air(not enoughto fullycombustwaste)

Excess air(sufficient airto ensure‘complete’combustion)

feedstock in a chemical process, by coolingthe syngas. Pyrolysis can be used also forchemical feedstock recycling.

Advanced Thermal Treatment - Gasification

Gasification can be seen as being betweenpyrolysis and combustion in that it involvesthe partial oxidation of a substance (seeFigure 1). This means that air (oxygen) isadded but the amounts are not sufficient toallow the fuel to be completely oxidised andfull combustion to occur. The temperaturesemployed are typically above 650oC. Theprocess is largely exothermic but some heat

may be required to initialise and sustain thegasification process. The main product is asyngas, which contains carbon monoxide,hydrogen and methane. Typically, the gasgenerated from gasification will have acalorific value (NCV) of 4 – 10 MJ/Nm3. Theother main product of gasification is a solidresidue of non-combustible materials (ash)which contains a relatively low level ofcarbon.

For reference, the calorific value of syngasfrom pyrolysis and gasification is far lowerthan natural gas, which has a NCV of around38 MJ/Nm3.

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2. How it works

The current prevalent term used for a fuelproduced from combustible waste is RefuseDerived Fuel (RDF). The types oftechnologies used to prepare or segregate afuel fraction from MSW include MechanicalHeat Treatment (MHT) and MechanicalBiological Treatment (MBT), described inseparate Technology Breifs in this series.

A CEN Technical Committee (TC 343) iscurrently progressing standardisation workon fuels prepared from wastes, classifying aSolid Recovered Fuel (SRF). Preliminarystandards have been published in June 2006,and are following an evaluation process,during which the functioning of thespecifications will be verified. The technicalspecifications classify the SRF by thermalvalue, chlorine content and mercury content.For example, the thermal value class will bebased on the number of megajoules onekilogram of recovered fuel contains. Inaddition, there are many characteristics forwhich no specific values have beendetermined. Instead, they can be agreedupon between the producer and thepurchaser of SRF.

Along with the standardisation process, avalidation project called QUOVADIS(http://quovadis.cesi.it/) on solid recoveredfuels is currently being implemented.

It is anticipated that once standards aredeveloped and become accepted by users,then SRF will become the terminology usedby the waste management industry. Otherterminology has also been introduced to theindustry as various fuel compositions may beprepared from waste by different processes.Examples include ‘Biodegradable FuelProduct’ (BFP) and ‘Refined RenewableBiomass Fuel’ (RRBF).

European standards for SRF are importantfor the facilitation of trans-boundaryshipments and access to permits for the useof recovered fuels. There may also be costsavings for co-incineration plants as a resultof reduced measurements (e.g. for heavymetals) of incoming fuels. Standards will aidthe rationalisation of design criteria forcombustion units, and consequently costsavings for equipment manufacturers.Importantly standards will guarantee thequality of fuel for energy producers.

Box 2 Fuel from mixed waste processing operations

2.4 Incineration Technology Overview

The actual plant design and configuration ofincineration plant will differ considerablybetween technology providers. However, anincinerator with energy recovery will typicallycomprise the following key elements:

• waste reception and handling

• combustion chamber

• energy recovery plant

• emissions clean-up for combustion gases

• bottom ash handling and air pollutioncontrol residue handling

Waste Reception and Handling

The incineration of MSW can be focused oneither combustion of the raw residual wasteor of pre-treated feed, for example a RefuseDerived Fuel (RDF). Plant configuration willchange according to the feedstock. Typically,the application of incineration in the UK is totake untreated residual MSW. The MSW isnormally delivered via a waste collectionvehicle and tipped into a bunker where it ismixed. The mixing is required to blend thewaste to ensure that the energy input(calorific value of the waste feed) to thecombustion chamber is as even as possible.

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2. How it works

Raw MSW typically has an energy content of9 - 11MJ/kg, whereas an RDF can have anenergy content of 17MJ/kg. Typically whereraw MSW is processed into an RDF, theincrease in the energy content of the RDF isachieved due to the drying of the waste(removal of water) and the removal ofrecyclables (glass, metals) and inerts (stonesetc), which do not contribute to the energycontent of the waste. Therefore, theremaining waste going into the RDF mainlycomprises wastes with significant energycontent, plastics, dried biodegradablematerials, textiles etc.

Within this Brief, RDF will be used as a termto cover the various fuel products processedfrom MSW. Box 2 describes the developmentof European Standards for RDF.

Combustion Technology

There are four combustion technologies thatcan be employed to burn MSW or RDF. Abrief overview of the main combustiontechnologies is presented overleaf in table 1.All of the combustion technologies presentedcan be designed to meet the technicalrequirements of the WID, e.g. a minimumtemperature of 850oC and a two secondresidence time for processing MSW.

Energy Recovery

The standard approach for the recovery ofenergy from the incineration of MSW is toutilise the combustion heat through a boilerto generate steam. Of the total availableenergy in the waste up to 80% can beretrieved in the boiler to produce steam. Thesteam can be used for the generation ofpower via a steam turbine and/or used forheating. An energy recovery plant thatproduces both heat and power is commonlyreferred to as a Combined Heat and Power(CHP) Plant and this is the most efficientoption overall for utilising recovered energyfrom waste via a steam boiler.

An incinerator producing exclusively heat canhave a thermal generating efficiency ofaround 80 - 90%; this heat may be used toraise steam for electrical generation atapproximately 17 - 30% efficiency9. Thechoice of a steam turbine generator set toproduce electricity will limit the upperefficiency based on acceptable boilertemperatures. A modern incineratorproducing only electricity from the steam maytherefore achieve a maximum electricalgenerating efficiency of 27%10, with a typicalefficiency range being from 14% to 24%. Arecent Defra 'Carbon Balances' report statesan efficiency range for electricity only ofbetween 20-27%11.

9 IPPC Reference document on Best Available Technologies for Waste Incineration, August 2006. Please note that the efficiency quoted isbased on the boiler efficiency and not the energy input to the plant and therefore the efficiency does not take account of flue gas losses.

10Waste Technology Data Centre - Incineration overview http://www.environment-agency.gov.uk/wtd/679004/1491670/?lang=_e11Carbon Balances and Energy Impacts of the Management of UK Wastes, ERM and Golder Associates report for Defra, March 2006

www.defra.gov.uk/science/project_data/DocumentLibrary/WR0602/WR0602_4750_FRP.pdf

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2. How it works

Table 1: Incineration technologies

Technology Description

GrateTechnologies

MOVING GRATEThe moving grate furnace system is the most commonly used combustion system for high through-putMSW processing in the UK. The waste is slowly propelled through the combustion chamber (furnace)by a mechanically actuated grate. Waste continuously enters one end of the furnace and ash iscontinuously discharged at the other. The plant is configured to enable complete combustion as thewaste moves through the furnace. Process conditions are controlled to optimise the wastecombustion, to ensure complete combustion of the feed. The end of the grate normally passes the hotash to a quench to rapidly cool the remaining non-combustibles.

There are three main sub categories of moving grate combustion systems used for MSW. These are asfollows:

The Roller Grate – this consists of adjacent drum or rollers located in a stepped formation, with thedrums rotating in the direction of the waste movement

The Stepped Inclined Grate – this system uses bars, rockers or vibration to move the waste downeach of the grates (typically three)

Inclined Counter-Rotating Grates – grate bars rotate backwards to agitate the waste and prevent ittumbling down the forward inclined grate until burn out is complete.

FIXED GRATESThese are typically a series of steps (normally 3) with the waste being moved by a series of rams. Thefirst step is a drying stage and initial combustion phase, the second is where the remainingcombustion takes place and the third grate is for final carbon burn-out.

Fluidised Bed The combustion of MSW using a fluidised bed (FB) technique involves pre-sorting of MSW material toremove heavy and inert objects, such as metals, prior to processing in the furnace. The waste is thenmechanically processed to reduce the particle size. Overall, the waste requires more preparation than if amoving grate was used. The combustion is normally a single stage process and consists of a lined chamberwith a granular bubbling bed of an inert material such as coarse sand/silica or similar bed medium.

The bed is ‘fluidised’ by air (which may be diluted with recycled flue gas) being blown verticallythrough the material at a high flow rate. Wastes are mobilised by the action of this fluidised bed ofparticles.

There are two main sub-categories of fluidised bed combustors:

Bubbling FB – the airflow is sufficient to mobilise the bed and provide good contact with the waste.The airflow is not high enough to allow large amounts of solids to be carried out of the combustionchamber.

Circulating FB – the airflow for this type of unit is higher and therefore particles are carried out ofthe combustion chamber by the flue gas. The solids are removed and returned to the bed.

The use of fluidised bed technology for MSW incineration is limited in the UK, although it is widely appliedto sewage sludge. Examples of this technology being used in the UK on pre-sorted waste include theincinerator in Dundee and the new incinerator which is being built at Alington in Kent.

Rotary Kiln Rotary kilns have wide application and can be a complete rotation vessel or partial rotational type.Incineration in a rotary kiln is normally a two stage process consisting of a kiln and separate secondarycombustion chamber. The kiln is the primary combustion chamber and is inclined downwards from thefeed entry point. The rotation moves the waste through the kiln with a tumbling action whichexposes the waste to heat and oxygen. There is also a proprietary system which oscillates a rotatingkiln for smaller scale incineration of MSW with energy recovery.

In the UK there is currently one oscillating type rotary kiln incinerator processing MSW, which is inNorth East Lincolnshire.

For an incinerator that produces combinedheat and power (CHP plant), the electricaland thermal generating efficiencies will varydepending on the split between the twoforms of energy (heat and power).

An incinerator will typically have a higher netelectrical and thermal efficiency than acomparable ATT process12 that also generatessteam for power generation or direct heating.This is mainly due to the energy required tosustain the gasification or pyrolysis process. Itis possible that ATT can be used with anotherpower generation technologies other than asteam turbine. For example, the syngas froman ATT could potentially be used in a gasengine or gas turbine (operating in combinedcycle mode). Using these power generationoptions it is possible that higher efficiencies forpower generation can be achieved comparedto generating steam from burning the syngasand supplying this to a steam turbine.

In contrast, the efficiency of an incinerator forpower generation is lower than a large coalfired or gas fired power station. Typically, acoal fired power station will have anefficiency of 33% - 38%; a combined cycle gasturbine (CCGT) power station can have anelectrical efficiency in excess of 50%. Thereason for the higher efficiencies is acombination of technical issues and the farlarger scale of coal and gas fired power plant.Where the energy recovered from anincinerator is used to generate steam forheating, the efficiency is comparable with aboiler fired with natural gas or oil. It ispossible that in future the efficiency ofelectricity generation using incineration willincrease given the trend in other solid fuelapplications of more severe operatingconditions at higher temperature becoming

more achievable.

The actual electrical and/or heat output from anincinerator is dependent on the availablemarkets. Electricity can easily be supplied intothe national grid and therefore sold anddistributed. In contrast heat will need to beused locally to the incinerator. The use of heatwill therefore be dependent on identifying andestablishing a local need, e.g. a district heatingsystem for buildings/housing and/or supply ofheat to a factory for industrial use. The UKdoes not have a history of district heatingsystems (with the exception of the systemassociated with the Sheffield CHP facility)having relied on in part on indigenous fossilfuel reserves, unlike Scandinavian countrieswhere it is common place using locally availableresources such as wood and peat. Withincreasing energy costs, district heating maybecome financially attractive in the UK.

Emissions Control for Releases to Atmosphere

The emissions limits for specific pollutantsthat are present in the combustion products(flue gases) from the incineration of MSW aredefined in the WID and applied through thePPC Regulations. A PPC permit will berequired to operate an incinerator fuelled byMSW in the UK and will set-out a range ofconditions including the emission limits forreleases to atmosphere.

To meet these emissions limits, thecombustion process must be correctlycontrolled and the flue gases cleaned prior totheir final release. The technology supplierfor the incinerator plant will define the exactemissions clean-up processes that will beemployed. A common approach for controlof emissions is as follows:

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2. How it works

12The Viability of Advanced Thermal Treatment of MSW in the UK, Fitchner 2004. This is based on an incineration plant and ATT plantgenerating steam for power or heat production at comparable process conditions.

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2. How it works

• ammonia injection into the hot flue gasesfor control of NOx emissions

• lime or Sodium Bicarbonate injection forcontrol of SO2 and HCl

• carbon injection for capture of heavy metals

• filter system for removal of fly ash and othersolids (lime or bicarbonate and carbon)

The control of CO, VOCs and dioxins in terms oftheir concentration is primarily though correctcombustion conditions being maintained. Formore information on flue gas cleaning see theIPPC Reference Document on Best AvailableTechniques for waste incineration.

The clean-up of the flue gases will producesolid residues comprising fly-ash,lime/bicarbonate and carbon. These residuesare usually combined (although some systemsmay separate fly ash and other components)and are often referred to as Air PollutionControl (APC) residues and are classified ashazardous waste, therefore their disposalmust be undertaken in accordance with

relevant regulations and guidance. Typically,the weight of APCRs produced will be around2% - 6% of the weight of the waste enteringthe incinerator.

Bottom Ash Handling

The main residual material from theincineration of MSW is referred to as “bottomash13”. This is the residual material in thecombustion chamber and consists of the non-combustible constituents of the waste feed.The bottom ash typically represents around20% - 30% of the original waste feed byweight, only about 10% by volume. Thebottom ash is continually discharged from thecombustion chamber and is then cooled. Theamount of ash will depend on the level ofwaste pre-treatment prior to entering theincinerator and will also contain metals thatcan be recovered for recycling.

13Sometimes also referred to as ‘IBA’, Incinerator Bottom Ash

3. Markets and outlets for the outputs

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Incineration processes all produce a solidresidue (bottom ash). Some systems are alsodesigned with mechanical preparation andsorting equipment to extract recyclablesbefore or after combustion. The table belowsummarises the key outputs from incinerationprocesses and the following sections addressmaterials and energy recovery.

Table 2: Outputs from incinerationtechnologies

3.1 Recovery from Incineration

Materials Recycling

Recyclables derived from either the front endpreparation stage of an Incineration plant ormetals extracted from the back end of theprocess (i.e. out of the ash) are typically of alower quality than those derived from aseparate household recyclate collectionsystem and therefore have a lower potentialfor high value markets. The types of materialsrecovered from Incineration processes almostalways include metals (ferrous and sometimesnon-ferrous). However these facilities canhelp enhance overall recycling levels,although do not contribute to recycling BVPIscurrently if material recovery is post-combustion, and enable recovery of certainconstituent parts that would not otherwise becollected in household systems (e.g. steel coathangers, scrap metal etc.).

Outputs State Quantity by Wt ofOriginalWaste

Comment

IncineratorBottom Ash(IBA)

Solidresidue

20%-30% Potential useas aggregatereplacementor nonbiodegradable,non-hazardouswaste fordisposal

Metals(ferrous andnon-ferrous)

Requiresseparationfrom MSWor IBA

2-5% Sold for re-smelting

APC residues(includingfly ash,reagentsand wastewater)

Solidresidue/liquid

2-6% Hazardouswaste fordisposal

Emissions toatmosphere

Gaseous Represents~70%–75%

Cleanedcombustionproducts

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3. Markets and outlets for the outputs

The IBA produced can then be potentiallyrecycled as a secondary aggregate. However,the recycling of IBA would need to beundertaken in accordance with relevantlegislation and guidance14. Typically bottomash is used as fill or in masonry productssubject to specific conditions in terms of thedeployment of the materials.

The extraction of materials for recycling priorto combustion contributes to recyclingtargets. For more information on thecontribution of Incineration to Best ValuePerformance Indicators and recycling seesection 9 and for the latest developments, seehttp://www.defra.gov.uk/environment/waste/localauth/perform-manage/index.htm.

Further information on bottom ash use as asecondary aggregate can be found at:

www.aggregain.org.uk/case_studies/2691_performance.html

Energy Recovery

Incineration processes are designed to recoverenergy from the waste processed bygenerating electricity and / or heat for use onsite and export off site. The useful energythat can be generated from an incinerationplant using a boiler to generate steam ispresented in table 3. Electricity generatedfrom the biodegradable fraction of waste inan incinerator with good quality heat andpower can benefit from support under theRenewables Obligation.

Table 3: Examples of Energy Efficiency forIncineration

* The lower efficiency performance is more typical of older facilitiesand it is possible that in the future the efficiency of electricitygeneration using incineration will increase

Outputs Efficiency Use

Heat Only Up to 80–90%15

thermalefficiency

Local district heatingfor buildings(residential,commercial) and orfor industrialprocesses

Electricity 14%-27%* Can be supplied tonational grid for saleand distribution

Heat andPower

Dependent onspecific demandfor heat andpower

Combination of above

14The Environmental Services Association (ESA) has facilitated an initiative to identify a protocol for the ecotoxicity testing of IncinerationBottom Ash (IBA). The protocol uses a direct testing method on IBA.

15IPPC Reference document on Best Available Technologies for Waste Incineration, August 2006. Please note that the efficiency quoted isbased on the boiler efficiency and not the energy input to the plant and therefore the efficiency does not take account of flue gas losses.

15

4. Track record

Incinerator Plant Scale Energy recovery EstablishedWebsite for further

information

Edmonton 500,000tpa Electricity, 32MW 1975 www.londonwaste.co.uk

SELCHP 420,000tpa Electricity, 32MW 1994 www.selchp.com

Tysesley Birmingham 350,000tpa Electricity, 25MW 1996 www.onyxgroup.co.uk

Cleveland 245,000tpa Electricity, 20MW 1998 www.sita.co.uk

Coventry 240,000tpa Electricity, 17.7MW & Heat 1975 www.cswdc.co.uk

Stoke 200,000tpa Electricity, 12.5MW 1997 www.mes-e.co.uk

Marchwood 165,000tpa Electricity, 14MW 2004 www.onyxgroup.co.uk

Portsmouth 165,000tpa Electricity, 14MW 2005 www.onyxgroup.co.uk

Nottingham 150,000tpa Electricity & Heat (max 20MW heat) 1973 www.wrg.co.uk

Sheffield 225,000tpa Electricity, 19MW (max) & 39Heat (max) 2006 www.onyxsheffield.co.uk

Dundee 120,000tpa Electricity, 8.3MW 2000 www.bbcel.co.uk

Wolverhampton 105,000tpa Electricity, 7MW 1998 www.mes-e.co.uk

Dudley 90,000tpa Electricity, 7MW 1998 www.mes-e.co.uk

Chineham 90,000tpa Electricity, 7MW 2003 www.onyxgroup.co.uk

Kirklees 136,000tpa Electricity, 9W 2002 www.sita.co.uk

Douglas (Isle of Man) 60,000tpa Electricity, 6MW 2004 www.sita.co.im

North East Lincolnshire 56,000tpa Electricity, 3MW & Heat, 3MW 2004 www.groupe-tiru.com

Shetland 23,000tpa Heat 2000 www.shetland.gov.uk

Isles of Scilly 3,700tpa No energy recovery 1987 www.scilly.gov.uk

Table 4: MSW Incineration Plant in UK

4.1 UK Experience

The term Incineration for the purposes of thisdocument covers those technologies thatdirectly combust waste and then recover theenergy for generating electricity (power)and/or heat.

In terms of its current status incinerationaccounts for the disposal of 9% of the totalMSW produced in England in 2005/6 whichequates to approximately 2.8 million tonnesper annum. The UK has 19 incinerators inoperation processing MSW. The scale ofthese facilities in terms of annual wastethroughput varies from 23,000 tonnes to600,000 tonnes. A full list of UK Incinerationfacilities is presented in Table 4. In additionto the operational facilities presented inTable 4 further incineration plant are beingconsidered or in the process of being

commissioned for the UK. Examples ofincinerators which are being built or haverecently received planning permissioninclude:

• Alington, Kent (500,000tpa). Thisincinerator is due to come online in 2007.This will produce electricity and have anoutput of 40MW. Further information canbe found at www.kentenviropower.co.uk

• Belvedere, Bexley (585,000tpa) receivedplanning permission in June 2006). This willproduce around 66MW of electricity.http://www.coryenvironmental.co.uk/services

• Colnbrook, Slough (400,000tpa) is due forcompletion and commissioning in 2008.This plant will have an electricity output of32MW. Further information is available athttp://www.viridor-waste.co.uk/index.php?id=141

16

4. Track record

4.2 European Experience

In 2000 there were 304 large scale (wherelarge is assumed to be 30,000 tpa and above)incineration sites, 291 of these process MSWwith energy recovery, operating in 18Western European countries. These sitesprocessed about 50 million tonnes of wasteper year which accounted for 50 TWh ofenergy recovered (40 million tonnes of oilequivalent)16.

Denmark, France, Switzerland and theNetherlands have the largest installedincineration capacities as a percentage oftotal MSW generated. The current trend is forlarger facilities to realise cost savings per unitof waste processed, most also featurematerial recovery operations in parallel withthe incineration plant.

Incineration is also widely utilised outside ofEurope with facilities in operation in mostdeveloped countries.

Some descriptive examples of Incinerationprocesses are included here to illustrate thedifferent technologies being promoted forMSW management. The technical details ofthese and other examples, including mass andenergy balances and an analysis of theStrengths, Weaknesses, Opportunities andThreats are included on the WasteTechnology Data Centre.

www.environment-agency.gov.uk/wtd

Example of Small Scale Incineration, Shetland

The Shetland and Orkney Isles have enteredinto a waste management partnership thathas resulted in the installation of anincinerator in Lerwick on Shetland. Theincinerator processes approximately 23,000tonnes of MSW per annum. This is thesmallest and only MSW incinerator in the UK.

The planning for the facility commenced in1992 and the time required through tocommissioning was approximately 8 years,with the plant being operation in 2000. Theplant has been designed to meet with allrelevant legislation including the WID.

The proposed plant was designed to provideheat which is supplied to both commercialand domestic customers. The thermalefficiency of the incinerator in terms of heatrecovered is 80%. The capital cost for theincinerator plant was approximately £10mand the district heating network a further£11.5m. The heat supplied is provided at acompetitive rate and has been well receivedby the end consumers. The cost of installingthe heat exchangers per property to allowthe heat to be used is between £2,000 and£5,000. The incinerator and heating networkprovide a significant financial benefit to theShetland Isles.

Integrating incineration with the proximityprinciple, Marchwood Hampshire

Hampshire’s waste management strategy forMSW includes the development of threeincineration plants. The public rejected asingle, more economic large scale incineratorin favour of three smaller scale facilitiesdistributed around the county. One of thethree incinerators is located at Marchwoodand is the focus for this case study.

The Marchwood incinerator is sized to accept165,000 tonnes of waste per year and hasbeen designed to serve the needs of thesouth-west of the county. The original planfor developing a waste management strategywhich included incineration was put forwardin the early 1990s. Planning permission forthe incinerator was granted in 2001 and itwas commissioned in late 2004. Theincinerator generates sufficient electricity to

16http://www.assurre.org/downloads/archive/d455ebd0-fdf2-409f-80b6-

17

4. Track record

export 14MW to the local grid, which isenough power for 14,000 homes. Theincinerator is clad in an aluminium domewhich is 36m high and 110 metres indiameter. The chimney is approximately 65mhigh.

The delivery of the incinerator at Marchwoodis part of an overall long-term wastemanagement contract which was let byHampshire Waste Services in 1996, whichincluded new transfer stations, compostingplants, material recovery facilities and twofurther incinerators at Chineham andPortsmouth.

Example of CHP – Switzerland

In the early 1980sSwitzerlandcommenced a stepchange in the way theymanaged theirmunicipal waste. Thekey driver for this waslack of availability and public opposition tolandfill. As a result Switzerland is now one ofthe most advanced countries in the world inwaste management, specifically in terms ofincineration, biogas fermentation andrecycling which is currently set at 46% of thetotal amount of waste generated.

Since 2000 all non-recycled combustible wastemust be incinerated in one of the 29 plants inSwitzerland, such as the plant in Thun.

The Thun incineration plant was opened in2004 in a residential area and in closeproximity to thousands of tourists at a capitalcost of approximately £82million. The plant isthe country’s newest facility and has anannual capacity of 100,000 tonnes, providingthe 300,000 residents in the area with a thirdof their electricity consumption requirements,as well as district heating for public sectorfacilities.

The conversion from steam to electricity andheat takes place in a turbine generator setconsisting of an extraction/condensationturbine with regulated low-pressureextraction and ports for district heat output.The plant is designed to produce a maximumof 12 MW of electricity and 25 MW of districtheat.

High standards were applied not only to theplant’s technology, but to its architecture aswell. The design of the plant is said to showa building complex with an air of calmcontrol. Visually it does not hide itself awaywith excessive screening, in fact the focalpoint is a glass façade that showcases thetechnology within and enhances the idea oftransparency as a process and of themunicipal authority.

5.1 Grants & Funding

Development of Incineration facilities plantwill involve high capital expenditure of manymillion pounds. There are a number ofpotential funding sources for LocalAuthorities planning to develop suchfacilities, including:

Capital Grants: general grants may beavailable from national economic initiativesand EU structural funds;

Prudential Borrowing: the LocalGovernment Act 2003 provides for a'prudential' system of capital finance controls;

PFI Credits and Private Sector Financing:under the Private Finance Initiative a wasteauthority can obtain grant funding fromcentral Government to support the capitalexpenditure required to deliver new facilities.This grant has the effect of reducing thefinancing costs for the Private Sector, therebyreducing the charge for the treatment service;

Other Private-Sector Financing: acontractor may be willing to enter a contractto provide a new facility and operate it. Thecontractor’s charges for this may be expressedas gate fees; and

Existing sources of local authorityfunding: for example National Non-DomesticRate payments (distributed by centralgovernment), credit (borrowing) approvals,local tax raising powers (council tax), incomefrom rents, fees, charges and asset sales(capital receipts). In practice capacity for thiswill be limited but generally it is throughraising taxes.

The Government is encouraging the use ofdifferent funding streams, otherwise knownas a ‘mixed economy’ for the financing andprocurement of new waste infrastructure toreflect the varying needs of local authorities.

Contractual Arrangements

Medium and large scale municipal wastemanagement contracts, since January 2007,are procured through EU CompetitiveDialogue (CD). This is dialogue between anauthority and the bidders with the aim ofdeveloping a suitable technical or legalposition against which all the bidders cansubmit a formal bid. More information on CDis available from the 4ps website.

The available contractual arrangementbetween the private sector provider (PSP) andthe waste disposal authority (or partnership)may be one of the following:

Separate Design; Build; Operate; andFinance: The waste authority contractsseparately for the works and services needed,and provides funding by raising capital foreach of the main contracts. The contract tobuild the facility would be based on thecouncil’s design and specification and thecouncil would own the facility onceconstructed;

Design & Build; Operate; Finance: Acontract is let for the private sector to provideboth the design and construction of a facilityto specified performance requirements. Thewaste authority owns the facility that isconstructed and makes separatearrangements to raise capital. Operationwould be arranged through a separateOperation and Maintenance contract;

18

5. Contractual and financing issues

19

5. Contractual and financing issues

Design, Build and Operate; Finance: TheDesign and Build and Operation andMaintenance contracts are combined. Thewaste authority owns the facility onceconstructed and makes separatearrangements to raise capital;

Design, Build, Finance and Operate(DBFO): This contract is a Design and Buildand Operate but the contractor also providesthe financing of the project. The contractordesigns, constructs and operates the plant toagreed performance requirements. Regularperformance payments are made over a fixedterm to recover capital and financing costs,operating and maintenance expenses, plus areasonable return. At the end of the contract,the facility is usually transferred back to theclient in a specified condition; and

DBFO with PFI: This is a Design, Build,Finance and Operate contract, but it isprocured under the Private Finance Initiative.In this case the waste authority obtains grantfunding from Government as a supplement tofinance from its own and private sectorsources. The PFI grant is only eligible forfacilities treating residual waste and ispayable once capital expenditure is incurred.

The majority of large scale wastemanagement contracts currently beingprocured in England are Design, Build,Finance and Operate contracts and manywaste disposal authorities in two tier Englisharrangements (County Councils) are currentlyseeking to partner with their WasteCollection Authorities (usually District orBorough Councils). Sometimes partnershipsare also formed with neighbouring UnitaryAuthorities to maximise the efficiency of thewaste management service and make thecontract more attractive to the Private SectorProvider.

Contracts are becoming more ‘output’ ledsince contractors increasingly have to buildproposals around obligated targets placed onauthorities such as BVPIs and landfillallowance targets.

Before initiating any procurement or fundingprocess for a new waste managementtreatment facility, the following issues shouldbe considered: performance requirements;waste inputs; project duration; project cost;available budgets; availability of sites;planning status; interface with existingcontracts; timescales; governance and decisionmaking arrangements; market appetite andrisk allocation.

Further guidance on these issues can beobtained from:

• Local Authority fundinghttp://www.defra.gov.uk/environment/waste/localauth/funding/pfi/index.htm

• The Local Government PFI project supportguidewww.local.odpm.gov.uk/pfi/grantcond.pdf

• For Works Contracts: the Institution of CivilEngineers ‘New Engineering Contract’(available at www.ice.org.uk).

• For large scale Waste Services Contractsthrough PFI and guidance on waste sectorprojects see the 4ps, local government'sproject delivery organisation http://www.4ps.gov.uk/PageContent.aspx?id=90&tp=Y

20

6. Planning and permitting issues

This section contains information on theplanning and regulatory issues associatedwith incineration facilities based on legislativerequirements, formal guidance, good practiceand in particular drawing on informationcontained in the Office of the Deputy PrimeMinister’s research report on waste planningpublished in August 200417.

6.1 Planning Application Requirements

All development activities are covered byPlanning laws and regulations. Minordevelopment may be allowed underPermitted Development rights but in almostall cases new development proposals forwaste facilities will require planningpermission.

Under certain circumstances new wastefacilities can be developed on sites previouslyused for General Industrial (B2) or Storageand Distribution (B8) activities. In practiceeven where existing buildings are to be usedto accommodate new waste processes,variations to existing permissions are likely tobe required to reflect changes in trafficmovements, emissions etc.

Under changes to the planning systemintroduced in 2006 all waste development isnow classed as ‘Major Development’. This hasimplications with respect to the level ofinformation that the planning authority willexpect to accompany the application and alsowith respect to the likely planningdetermination period. The targetdetermination periods for differentapplications are:

• Standard Application – 8 weeks

• Major Development - 13 weeks

• EIA Development - 16 weeks

The principal national planning policyobjectives associated with waste managementactivities are set out in Planning PolicyStatement (PPS) 10 ‘Planning for SustainableWaste Management’ published in July 2005.Supplementary guidance is also containedwithin the Companion Guide to PPS 10. Bothof these documents can be accessed via theDepartment of Communities and LocalGovernment (DCLG) website18.

PPS 10 places the emphasis on the plan ledsystem which should facilitate thedevelopment of new waste facilities throughthe identification of sites and policies in therelevant local development plan. Separateguidance on the content and validation ofplanning applications is also available fromDCLG through their website19. IndividualPlanning Authorities can set out their ownrequirements with respect to supportinginformation and design criteria throughSupplementary Planning Documents linked tothe Local Development Framework. It isimportant that prospective developers liaiseclosely with their Local Planning Authoritiesover the content and scope of planningapplications.

17 http://www.communities.gov.uk/embeddedindex.asp?id=114571118http://www.communities.gov.uk/index.asp?id=114383419http://www.communities.gov.uk/pub/494/BestPracticeGuidanceontheValidationofPlanningApplicationsPDF326Kb_id1144494.pdf

21

6. Planning and permitting issues

6.2 Key Issues

When considering the planning implicationsof an incineration plant the key issues thatwill need to be considered are common tomost waste management facilities and are:

• Plant/Facility Siting;

• Traffic;

• Air Emissions / Health Effects;

• Dust / Odour;

• Flies, Vermin and Birds;

• Noise;

• Litter;

• Water Resources;

• Visual Intrusion; and

• Public Concern.

A brief overview of the planning context foreach of these issues is provided below.

6.3 Plant Siting

PPS 10 and its Companion Guide containgeneral guidance on the selection of sitessuitable for waste facilities. This guidancedoes not differentiate between facility types.

The following general criteria would apply tothe siting of new incineration plants:

• Incineration processes can be similar inappearance and characteristics to variousprocess industries. It would often besuitable to locate facilities on landpreviously used for general industrialactivities or land allocated in developmentplans for such (B2) uses;

• Facilities are likely to require goodtransport infrastructure. Such sites shouldeither be located close to the primary roadnetwork or alternatively have the potentialto be accessed by rail or barge;

• The location of such plants together withother waste operations such as MBT/MHTand residual waste MRFs can beadvantageous in providing a pre-treatedwaste derived fuel source. The potentialfor co-location of such facilities on resourcerecovery parks or similar is also highlightedin PPS 10 and the Companion Guide;

• The potential for export of energy to hostusers or the national grid should also be akey consideration in the siting ofincineration plants; and

• Unlike a number of other new wastetreatment processes incineration proposalsare likely to have very exacting siting anddesign requirements. This is due in part tonegative public perception but also to thescale of operations which will often requiresites that are capable of accommodatinglarge built structures and associatedinfrastructure.

6.4 Traffic

Incineration facilities may be served by largenumbers of HGVs (depending on the scale ofthe facility) with a potential impact on localroads and the amenity of local residents. It islikely that the site layout/road configurationwill need to be suitable to accept a range oflight and heavy vehicles. For a 50,000tpacapacity plant, up to 20 Refuse CollectionVehicles per day would be anticipated.

6.5 Air Emissions / Health Effects

In common with any combustion process,combustion of waste results in the release offlue gases to the atmosphere. It is importantto ensure that emissions of air pollutants areminimised and/or removed in accordancewith the strict emission limits in EuropeanCommission Directive 2000/76/EC on theIncineration of Waste. This Directive sets themost stringent emissions controls for any typeof thermal process regulated in the EU.

22

6. Planning and permitting issues

The control of emissions from a wasteincinerator starts with the design of thecombustion process. This ensures good mixingof waste to provide complete burn-out ofwaste materials. The flue gases aremaintained at high temperature for aspecified minimum time, before being rapidlycooled. These stages minimise the formationof potentially harmful substances. Followingthe combustion stage, the flue gases arenormally treated to remove oxides ofnitrogen, mercury, dioxins and furans, andacid gases, although specific treatment maynot be needed if the in-process controls givethe required performance. The air stream isthen passed through a bag filter to removeparticulate matter. The residual emissions toair from waste incineration processes aredischarged from a stack which is designed toprovide sufficient dispersion of the low levelsof remaining air pollutants.

Waste incineration processes are nowdesigned and operated so that residualemissions of pollutants comply with theemission limits set out in the WasteIncineration Directive (2000/76/EC). Wasteincineration facilities need to rely on post-combustion gas clean-up measures such asthose described above to achieve therequirements of the Directive. The use of anair filtration system to remove particulatematter from the flue gases results in a fine,dusty waste stream referred to as “airpollution control residues” (or in some casesFlue Gas Treatment residues). This wastestream must be disposed of appropriately.

Emissions of many parameters need to bemonitored continuously. This enables processoperators to comply with the emissions limitsset out in operating permits, which as aminimum reflect those in the WasteIncineration Directive. Some substances,

including dioxins, furans and some metals,cannot be measured continuously or it maybe prohibitively expensive to do so. Somesubstances such as dioxins and furans can becontinuously sampled, with analysis carriedout periodically to give the average amountemitted over a longer period. Emissions ofsubstances which cannot be measuredcontinuously are normally measuredperiodically under the terms of the operatingpermit. Routine day-to-day control is achievedby ensuring that surrogate indicators such ascombustion temperature, particulateemissions and hydrogen chloride emissionsare within the permitted limits.

23

6. Planning and permitting issues

Incinerator emissions have reducedsubstantially over the past two decades –most emissions are less than 10% of the level20 years ago. Because waste incineration hasa long operating record, there is a gooddatabase of information on emissions andpotential health effects compared to otheroptions for managing waste. Emissions froman incinerator typical of those currentlyoperating in the UK (230,000 tonnes per year)are approximately equivalent to20:

• Oxides of nitrogen: Emissions from a 7 kmstretch of typical motorway

• Particulate matter: Emissions from a 5 kmstretch of typical motorway

• Dioxins and furans: Emissions fromaccidental fires in a town the size of MiltonKeynes

• Cadmium: A twentieth of the emissionsfrom a medium sized UK coal-fired powerstation.

These emissions are approximately equivalentover the same time period. So, emissions ofoxides of nitrogen from a typical incinerationover a period of an hour are approximatelythe same as emissions of oxides of nitrogenfrom a typical motorway 7 km in length overa one hour period.

An independent study21 on the Health andEnvironmental effects of waste managementis cited by the Health Protection Agency in itsposition statement on health effects22. Theindependent review and the HPA positionstatement both found that: “the weight ofevidence from studies so far indicates thatpresent day practice for managing solidmunicipal waste has, at most, a minor effecton human health and the environment,

particularly when compared to othereveryday activities”. Adverse health effectshave been reported in some studies ofpopulations living around older, morepolluting incinerators and in heavilyindustrialised areas. However, the currentgeneration of waste incinerators result inmuch lower levels of exposure to pollutants.In particular, there is no evidence for a linkbetween the incidence of cancers, respiratorydiseases and birth defects and the currentgeneration of incinerators. The HealthProtection Agency emphasises the need forongoing work to ensure that incinerators donot contribute significantly to ill-health.

6.6 Dust / Odour

Any waste management operations can giverise to dust and odours. These can beminimised by good building design;performing operations under controlledconditions indoors; good working practices;and effective management to suppress dustfrom vehicle movements. Additionally,incineration processes normally use the airdemand of the combustion process to operatethe working areas under negative pressure.This means that air is in general drawn intothe building through the waste handling areato minimise the risk of dust and odourproblems. With these controls in place, wasteincineration processes are not normallysources of dust and odour.

6.7 Flies, Vermin and Birds

The enclosed nature of waste incinerationoperations will limit the potential to attractvermin and birds. However, during hotweather it is possible that flies couldaccumulate, especially if they have beenbrought in during delivery of the waste.

20 Enviros Consulting Ltd, using Department for Transport Design Manual for Roads and Bridges, Defra review of Health and EnvironmentalEffects of Waste Management Facilities, National Atmospheric Emissions Inventory, and Environment Agency Pollution Inventory

21http://www.defra.gov.uk/environment/waste/research/health/pdf/health-summary.pdf22http://www.hpa.org.uk/chemicals/ippc/incineration_posn_statement.pdf

24

6. Planning and permitting issues

Effective housekeeping and on sitemanagement of tipping and storage areas isessential to minimise the risk from verminand other pests. In some operations wasteheat from the process may be used to bringtemperatures in fresh input waste to levelsabove which flies can live. The use of RDF as afeedstock would reduce this issue relative toraw waste.

6.8 Noise

Noise is an issue that will be controlled underthe waste permitting regulations and noiselevels at nearby sensitive receptors can belimited by a condition of a planningpermission. The main contributors to noiseassociated with incineration are likely to be:

• vehicle movements / manoeuvring;

• traffic noise on the local road networks;

• mechanical processing such as wastepreparation;

• air extraction fans and ventilation systems;

• steam turbine units; and

• air cooled condenser units

6.9 Litter

Any waste which contains plastics and paperis more likely to lead to litter problems. Withincineration litter problems can be minimisedas long as good working practices areadhered to and vehicles use covers andreception and processing are undertakenindoors.

6.10 Water Resources

In common with most thermal treatmentprocesses the enclosed nature of theoperations significantly reduces the potentialfor impacts on the water environment. Thegreatest potential for pollution to surfaceand ground water is linked to thearrangements for delivery of waste and

chemicals used for the treatment of fluegases. Under normal circumstances the risksare very low.

The level of water usage will be specific tothe technology and therefore it is notpossible to provide detail on the nature ofthe effluent that might be generated andhow it should be managed. However, as partof the permitting requirements for a facility amanagement plan would be required foreffluent.

The case studies on the Waste TechnologyData Centre include an assessment of waterusage.

6.11 Design Principles and VisualIntrusion

Planning guidance in PPS 10 emphasises theimportance of good design in new wastefacilities. Good design principles andarchitect input to the design and physicalappearance of large scale buildings such asincinerators is essential. Buildings should beof an intrinsically high standard and shouldnot need to be screened in most cases.

Good design principles also extend to otheraspects of the facility including issues such as:

• Site access and layout;

• Energy efficiency;

• Water efficiency; and

• General sustainability profile

Construction of any building will have aneffect on the visual landscape of an area.Visual intrusion issues should be dealt withon a site specific basis and the followingitems should be considered:

• Direct effect on landscape by removal ofitems such as trees or undertaking majorearthworks;

25

6. Planning and permitting issues

• Site setting; is the site close to listedbuildings, conservation areas or sensitiveviewpoints;

• Existing large buildings and structures inthe area;

• The potential of a stack associated withsome air clean up systems for mixed wasteprocessing operations may impact on visualintrusion;

• Appropriate use of landscaping features(trees, hedges, banks etc) not for screeningbut to enhance the setting of the facility;and

• The number of vehicles accessing the siteand their frequency.

Due to the scale of most incineration plant,consideration should be given to the value ofinvesting significant resources into theappearance of the building. Recent examplesof incinerators which have become iconiclandmark structures include those in the Isleof Man and Marchwood, Hampshire. Inmainland Europe, the Vienna incinerationplant in the centre of the city is an extremeexample..

6.12 Size and Landtake

Table 5 shows the land area required for thebuilding footprint and also for the entire site(including supporting site infrastructure) for

incineration facilities. For examples ofAdvanced Thermal Treatment facilities see theATT brief in this series.

Table 5: Landtake

Source: * Planning for Waste Management Facilities – A Research

Study, ODPM, August 2004# Based on Kent Enviropower facility in Allington, Kent

For more information on Landtake forspecific waste management operations, seethe Waste Technology Data Centre.

6.13 Public Concern

Section 7, Social and Perception Issues, relatesto public concern. In general public concernsabout waste facilities relate to amenity issues(odour, dust, noise, traffic, litter etc). Withthermal based facilities health concerns canalso be a key perceived issue. Public concernis a material planning consideration and hasin part led to previous applications beingrefused (e.g. Kidderminster). Public concernfounded upon valid planning reasons can betaken into account when considering aplanning application.

TT Facility

Size,tonnes

perannum

BuildingsAream2

TotalLandtake

Ha

IndicativeStack

Height

MediumSizedMovingGrateTechnology*

90,000 5850 1.7 65m

LargeMovingGrateTechnology*

250,000 6,600 4 70m

LargeFluidised BedTechnology#

500,000 70,000 34 80m

SmallOscillatingKilnTechnology*

70,000 3,500 4 60m

26

6. Planning and permitting issues

6.14 Environmental Impact Assessment

An Environmental Impact Assessment (EIA)will be required for an incineration facility aspart of the planning process.

Whether a development requires a statutoryEIA is defined under the Town and CountryPlanning (Environmental ImpactAssessment)(England and Wales) Regulations1999. The existing additional guidance in DETRcircular 02/99 is currently being revised. Thisnew guidance is likely to focus on appropriatecriteria for establishing need for EIA and notrelate to the general nature of proposals.

For more information on Planning issuesassociated with waste management optionssee Planning for Waste Management Facilities– A Research Study. ODPM, 2004 referencedin Further Reading.

6.15 Licensing/Permitting

Currently, the interpretation of allincineration operations is that they require aPollution Prevention & Control (PPC) permit.It would be prudent therefore to assume thatany facilities will be covered by the PPCRegulations. The Environmental PermittingProgramme (EPP) is due to be implemented inApril 2008 which will combine waste licensingand permitting systems.

For more information on licensing &permitting see the Environment Agencywebsite23.

Box 3 shows the key planning issuesassociated with the Lakeside facility locatedat Colnbrook, proposed operator LakesideEnergy from Waste Ltd. The planningauthority was Slough Borough Council.

Box 3 Lakeside incinerator, Slough

• Planning application for the 400,000tpa incinerator (termed an Energy fromWaste facility, EfW) was combined withthe redevelopment of the existingmaterials recycling facility (MRF) andclinical waste incinerator (CWI).

• The new incinerator is to be sitedwithin the footprint of the existingwaste management site; total footprint3.45 ha

• Site was identified as a protected site inthe Berkshire Waste Local Plan but nota preferred location for incineration

• Application submitted August 1999 andapproved June 2000; it drew very littlepublic opposition

• Application was subject to a 106agreement providing wider planninggain

• Full EIA conducted and EnvironmentalStatement included proposals for socialand environmental responsibilitymeasures including a visitors centre andmanagement plans for the adjacentlake to enhance ecological approval

• The redeveloped CWI and municipalwaste incinerator will share the sameemissions stack

23http://www.environment-agency.gov.uk/subjects/waste/?lang=_e

This section contains a discussion of the socialand environmental considerations ofincineration facilities.

7.1 Social Considerations

Any new facility is likely to impact on localresidents and may result in both positive andnegative impacts. Potential impacts on localamenity (odour, noise, dust, traffic, landscape)are important considerations when siting anywaste management facility. The Planning andPermitting chapter of this Brief provides anestimate of potential vehicle movements.

An incinerator may also provide positivesocial impacts in the form of employment,educational opportunities and potentially as acheap source of domestic or industrialheating. Typical employment for anincineration plant of 50,000tpa capacitywould be 2-6 workers per shift. The plantwould operate on a three shift system, toallow for 24-hour operations. These facilitiesare also likely to provide vocational trainingfor staff. New facilities may be built with avisitor centre to enable local groups to viewthe facility and learn more about how itoperates.

7.2 Public Perception

Changes in waste management arrangementsin local areas is gaining a higher profilethrough the media. Many people as a resultof greater publicity and targeted educationare now embracing the need for wastereduction, recycling and to a lesser extent theneed for new waste facilities. The widerperception of waste facilities as a badneighbour will take longer to overcome.New waste facilities of whatever type arerarely welcomed by residents close to wherethe facility is to be located.

Public opinion on waste management issues iswide ranging, and can often be at extremeends of the scale. Typically, the most positivelyviewed waste management options for MSWare recycling and composting. However, this isnot necessarily reflected in local attitudestowards the infrastructure commonlyrequired to process waste to compost, or sortmixed recyclables. It should be recognisedthat there is always likely to be someresistance to any waste management facilitywithin a locality.

The perception the public has of wasteincineration tends to be linked with issuesassociated with older facilities where thegeneral site management requirements andpollution control measures were not asexacting as they are today.

The emissions from incineration, particularthose to atmosphere, must be carefullycontrolled and monitored. The WID sets themost stringent emissions controls for any typeof thermal process regulated in the EU

The current position of the EnvironmentAgency as set out in their Position Statementin 2003 is that “The Agency is not aware ofany studies that conclusively link adversehealth outcomes to incinerator releases”. Inaddition to this the Health Protection Agencyposition statement on incineration foundthat: “the weight of evidence from studies sofar indicates that present day practice formanaging solid municipal waste has, at most,a minor effect on human health and theenvironment, particularly when compared toother everyday activities”.

The control of emissions and public concernrelating to releases from incineration to theenvironment are key issues which need to beconsidered as part of the assessment process.

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7. Social and perception issues

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8. Cost

The cost of constructing, operating andmaintaining Incineration facilities areaddressed using a common cost model onWaste Technology Data Centre. Both capitaland operating costs are included on specifictechnologies which may be used for thepurposes of indicative comparisons ratherthan accurate reflections of actual costs.

The capital costs for an incinerator will bedependent on the quality of waste to beprocessed, the technology employed and itslocation. Costs will not only comprise thoseassociated with the purchase of theincinerator plant, but also costs for landprocurement and preparation prior to buildand also indirect costs, such as planning,permitting, contractual support and technicaland financial services over the developmentcycle.

Examples of capital costs for incinerationplant are provided on Waste Technology DataCentre www.environment-agency.gov.uk/wtdand are summarised below:

• 50,000tpa £25m

• 136,000tpa £35m

• 265,000tpa £51m

Extreme care is required in utilising cost datasuch as that provided on the data centrewebsite as it might not be fully inclusive. Inaddition, site specific criteria need to betaken into account, which are summarisedabove and actual costs will vary on a case bycase basis.

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9.1 Recycling

Recyclate derived from an Incineration plantprocessing household waste qualifies for BVPI82a (Recycling) for any materials recoveredprior to the primary treatment reactor. Anymaterials recovered after the thermaltreatment (e.g. metals from the ash), do notcount towards BVPI 82a. Equally any ashrecycled does not count towards BVPI 82a.The material must pass to the reprocessor(and not be rejected for quality reasons) tocount as recycling. It should be noted thatsome materials may have market limitationsdue to being derived from a mixed MSWsource. For example British Standard BS EN643 states that ‘Recovered paper from refusesorting stations is not suitable for use in thepaper industry.’ Although this standard is notlegally binding, it is supported by the maintrade associations for the paper recyclingsector.

The Government has recently increasednational recycling and composting targets forhousehold waste through the Waste Strategyfor England 2007. Targets are at least 40% by2010, 45% by 2015 and 50% by 2020. Formore information on the contribution ofincineration to Best Value PerformanceIndicators and recycling see the localauthority performance pages on the Defrawebsite

http://www.defra.gov.uk/environment/waste/localauth/perform-manage/index.htm and

http://www.wastedataflow.org/Documents/BVPI%20FAQs.pdf

9. Contribution to national targets

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9. Contribution to national targets

9.2 Landfill Allowance Trading Scheme(LATS)

The European Landfill Directive and the UK’senabling act, the Waste & Emissions TradingAct 2003, require the diversion ofbiodegradable municipal waste (BMW) fromlandfill. Incineration systems will divert 100%of the BMW passing through the thermalprocess from landfill as the output (char orash) will not be classified as biodegradableeven if disposed to landfill. Up to dateinformation can be obtained from Defra’sLATS information webpage:

http://www.defra.gov.uk/environment/waste/localauth/lats/index.htm

9.3 Recovery

Incineration technologies will contributetowards recovery targets on the tonnage ofmaterials entering the thermal treatmentprocess as all processes are designed torecover energy. See the specific guidance forBVPI 82c (Recovery). The Government hasrecently increased national recovery targetsfor municipal waste through the WasteStrategy for England 2007. Targets are 53%by 2010, 67% by 2015 and 75% by 2020.

For more details see

http://www.defra.gov.uk/environment/waste/localauth/perform-manage/index.htm

9.4 Renewables

The Renewables Obligation (RO) wasintroduced in 2002 to promote thedevelopment of electricity generated fromrenewable sources of energy. The Obligationrequires licensed electricity suppliers to sourcea specific and annually increasing percentage

of the electricity they supply from renewablesources, demonstrated by RenewablesObligation Certificates (ROCs). The targetcurrently rises to 15.4% by 2015/16. Inessence, the RO provides a significant boostto the market price of renewable electricitygenerated in eligible technologies.

Electricity generated from the biomass(renewable) fraction of waste in incinerationplant with good quality heat and power iseligible for support under the RO. This canprovide an important additional revenuestream for a proposed plant, as long as itmeets the qualifying requirements. As thevalue of a ROC is not fixed, the long termvalue would need to be assessed in detail todetermine its overall financial value to theproject.

The Department for Industry (DTI) isconsidering providing greater support totechnologies producing renewable energyand assessing methods for removing barriersto renewable energy generation.

Up-to-date information regarding ROCs canbe obtained from the DTI website

www.dti. gov.uk/energy/sources/renewables/index.html.

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10. Further reading and sources ofinformation

WRATE (Waste and Resources Assessment Tool for the Environment)

http://www.environment-agency.gov.uk/wtd/1396237/?version=1&lang=_e

The Waste Technology Data Centre www.environment-agency.gov.uk/wtd

New Technologies Demonstrator Programme Wastetech@enviros.com

Defra New Technologies website

http://www.defra.gov.uk/environment/waste/wip/newtech/index.htm

Integrated Pollution Prevention and Control, Draft Reference Document on Best AvailableTechniques for the Waste Treatments Industries, European Commission – Directorate GeneralJoint Research Centre, January 2004

Energy from Waste – A Good Practice Guide, Energy from Waste working group, CIWM, 2003

Refuse Derived Fuel, Current Practice and Perspectives (B4-3040/2000/306517/Mar/E3), EuropeanCommission – Directorate General Environment, July 2003

Review of Environmental & Health Effects of Waste Management, Enviros Consulting Ltd,University of Birmingham, Open University & Maggie Thurgood. Defra 2004.

AiIE Ltd, 2003, Review of residual waste treatment technologies, Report prepared on behalf ofKingston upon Hull City Council and East Riding of Yorkshire Council

http/www.eastriding.gov.uk/environment/pdf/waste_treatment_technologies.pdf

The Additional Paper to the Strategy Unit, Waste Not Want Not study, ‘Delivering the LandfillDirective: The Role of New & Emerging Technologies’, Dr Stuart McLanaghan

http://www.number10.gov.uk/files/pdf/technologies-landfill.pdf

Planning for Waste Management Facilities – A Research Study. Office of the Deputy PrimeMinister, 2004.

http://www.communities.gov.uk/pub/713/PlanningforWasteManagementFacilitiesAResearchStudy_id1145713.pdf

Local Authority funding http://www.defra.gov.uk/environment/waste/localauth/funding/pfi/index.htm

The Local Government PFI project support guide www.local.odpm.gov.uk/pfi/grantcond.pdf

For Works Contracts: the Institution of Civil Engineers ‘New Engineering Contract’ (available atwww.ice.org.uk).

For large scale Waste Services Contracts through PFI and guidance on waste sector projects seethe 4ps, local government's project delivery organisation

http://www.4ps.gov.uk/PageContent.aspx?id=90&tp=Y

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11. Glossary11. Glossary

Advanced ThermalTreatment (ATT)

Waste management processes involving medium and high temperatures to recoverenergy from the waste. Primarily pyrolysis and gasification based processes,excludes incineration.

Aerobic In the presence of oxygen.

Animal By-ProductsRegulation

Legislation governing the processing of wastes derived from animal sources.

Biodegradable Capable of being degraded by plants and animals

Biodegradable MunicipalWaste (BMW)

The component of Municipal Solid Waste capable of being degraded by plants andanimals. Biodegradable Municipal Waste includes paper and card, food and gardenwaste, and a proportion of other wastes, such as textiles.

Co-combustion Combustion of wastes as a fuel in an industrial or other (non waste management)process.

Digestate Solid and / or liquid product resulting from Anaerobic Digestion.

Feedstock Raw material required for a process.

Floc A small loosely aggregated mass of flocculent material. In this instance referring toRefuse Derived Fuel or similar.

Gasification Gasification is the process whereby carbon based wastes are heated in the presenceof air or steam to produce a solid, low in carbon and a gas. The technology is basedon the reforming process used to produce town gas from coal.

Greenhouse Gas A term given to those gas compounds in the atmosphere that reflect heat backtoward earth rather than letting it escape freely into space. Several gases areinvolved, including carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O),ozone, water vapour and some of the chlorofluorocarbons.

Green Waste Waste vegetation and plant matter from household gardens, local authority parksand gardens and commercial landscaped gardens.

Incineration The controlled thermal treatment of waste by burning, either to reduce its volumeor toxicity. Energy recovery from incineration can be made by utilising the calorificvalue of the waste to produce heat and / or power.

Materials Recycling Facility/

Material Recovery Facility(MRF)

Dedicated facility for the sorting / separation of recyclable materials.

Mechanical BiologicalTreatment (MBT)

A generic term for mechanical sorting / separation technologies used in conjunctionwith biological treatment processes, such as composting.

Municipal Solid Waste(MSW)

Household waste and any other wastes collected by the Waste Collection Authority,or its agents, such as municipal parks and gardens waste, beach cleansing waste,commercial or industrial waste, and waste resulting from the clearance of fly-tipped materials.

Main Heading

Pyrolysis During Pyrolysis organic waste is heated in the absence of air to produce a mixtureof gaseous and/or liquid fuels and a solid, inert residue (mainly carbon)

Recyclate/Recyclablematerials

Post-use materials that can be recycled for the original purpose, or for differentpurposes.

Recycling Involves the processing of wastes, into either the same product or a different one.Many non-hazardous wastes such as paper, glass, cardboard, plastics and scrapmetals can be recycled. Hazardous wastes such as solvents can also be recycled byspecialist companies.

Refuse Derived Fuel (RDF) A fuel produced from combustible waste that can be stored and transported, orused directly on site to produce heat and/or power.

Renewables Obligation Introduced in 2002 by the Department of Trade and Industry, this system creates amarket in tradable renewable energy certificates (ROCs), within each electricitysupplier must demonstrate compliance with increasing Government targets forrenewable energy generation.

Solid Recovered Fuel Refuse Derived Fuel meeting a standard specification, currently under developmentby a CEN standards committee.

Source-segregated/

Source-separated

Usually applies to household waste collection systems where recyclable and/ororganic fractions of the waste stream are separated by the householder and areoften collected separately.

Statutory Best ValuePerformance Indicators

Local Authorities submit performance data to Government in the form of annualperformance indicators (PIs). The Recycling and Composting PIs have statutorytargets attached to them which Authorities are required to meet.

Syngas ‘Synthetic gas’ produced by the thermal decomposition of organic based materialsthrough pyrolysis and gasification processes. The gas is rich in methane, hydrogenand carbon monoxide and may be used as a fuel or directly combusted to generateelectricity.

11. Glossary