Solid Waste Evolution and Concepts p… · 50 = 30 + solid waste + 1 total amount of generated solid waste = 19 kg 25% of the solid waste is recycled = 0.25 * 19 = 4.75 kg is recycled

Section II Solid Waste Management – Waste Management

Liquid and solid Waste (0670545)

Very Important Note: Most of the figures and tables are downloaded from google

and various text books

Solid Waste Evolution and Concepts:

- Since the beginning of humanity, both humans and animals have been using earth

resources to support their life. As a result of these activities, waste is being

produced.

- At small community No waste problem, but when people starts live in bigger

communities (city) more waste produced ...... thus the demand for waste

management (WM) appear.

- Heterogeneous nature of commingled solid waste makes studying it not an easy job

What is waste:

- The term solid waste refers to thrown items that have no value for its owner

even though it may consider as a material or heat resources for other users.

Why we need to manage the solid waste (SW)?

- The relationship between public health and the improper waste storage, handling

and disposing is significant.

- Improper WM leads to suffer from rats and flies breeding and epidemic diseases.

- Reduce the pollution form waste and its emissions like Methane (CH4), hydrogen

sulphide (H2S), CO

- Protect ground water from leachate (العصارة)


Waste Classifications:

1- Classification in dependent on waste physical status

a- Solid

b- liquid

c- gas

2- classification based on waste nature:

a- hazardous waste: that has one of the hazardous characteristics that pose

human and environmental risks

b- non-hazardous waste

c- Medical waste

d- Special waste like tires, car batteries (acid lead) , used oil

HW# what are the

hazardous

characteristics??


3- Classification in dependent to wastegeneration source to the following:

a) Residential or Domestic waste:includes non-hazardous waste generated in

households,

It includes commercial,business establishments and institutions that has

same composition.

b) Commercial: all municipal solid waste generated from business

establishments such as stores, markets, office buildings, restaurants and

shopping centers.

c) Institutional: waste originating in universities, schools, hospitals, prisons,

research centers and other public buildings.

Note: since the commercial and institutional wastes are generated from

people activities thus its composition almost same as the domestic

d) Industrial:

- Heterogeneous mixture of different materials generated during an industrial

process.

- -It may be gaseous, liquid, sludge, or solid.

- -It's composition depends upon the natural resources, raw materials, markets,

and manufacturing process.


e-Agricultural:

- The solid waste resulted from plant cultivation activities such trees trimming

waste, grass, plastic house, and irrigation hoses.

f- Construction and Demolition:

- All solid waste generated from construction activities, dredging materials,

rubble (انقاض) resulting from construction, demolition of homes, and other

structures or pavements.

- The nature of this type of SW depends upon the used resources in a given

region or country for the purposes of construction.

g- Municipal Services:

- Street sweeping (cleaning), landscaping, parks and beaches


Organics (food waste), 48.9

Paper & Cardboard, 13.

3

Plastics, 15.2

Textile, 5.8

Rubber & Leather, 2.6

Metals, 3.1

Glass, 3.8

Miscellaneous,7.3

h-Treatment plant sites: such as sludge

I –Special waste: such as car tiers, consumer electronic and white goods (refrigerator,

washing machines), used oil.

Composition of Solid Waste

It’s the term used to describe the individual components that is included within a solid

waste stream and their relative distribution usually based on percentage by weight.

Waste composition in zarqa city (almost same as Jordanian waste composition)


- Waste composition is vary through the time due to changes in consumption

trend and life style.

- Waste composition is vary from one place to another

Main Components of SWComposition for Different Studies and time periods.

RSS

(1994 )

Fichtner

( 1996 )

CMCE

(2002 )

JUST

(2007 )

MoEnv. and RSS

(2009)

Study

Composition %by Weight

53.0 44.0 51.4 52.2 38.8 Organics

17.0 10.6 12.6 12.7 12.2 Paper and Cardboard

8.0 2.4 3.1 1.4 3.8 Metals

12.0 13.2 14.2 17.1 17.1 Plastics

10.0 1.4 1.8 2.5 2.6 Glass

- 4.7 4.2 - 8.5 Textile

- - 3.0 - 1.5 Rubber and Leather

- - 0.1 - 0.1 Hazardous waste

0.0 23.6 9.6 14.1 15.4 Miscellaneous

Ministry of Environment, (2009)


Comparison of Jordanian Solid Waste Contents with other Countries.

Waste

Composition

Jordan Asian

Countries

UK USA

Organic 50-68 75 36 20

Paper 5-10 2 31.2 43

Metal 3-6 0.1 5.3 7

glass 2-5 0.2 3.8 9

Plastic 4-6 0.1 5.2 5

Al-Ansari A. et al. (2005)

Example:

a family brings approximately 50 kg of consumer good a week (food,magazine ,

appliances…) of this amount 60% is consumed as food . half of the food is used for

biological maintenance and ultimately released as CO2 and the reminder is discharged

to sewer. The green recycle is about 25% of the solid waste that is generated.

Approximately 1kg is accumulated at home. Estimate the solid waste amount that

placed at curb each week??

Main equation:

Accumulation = input – output

consumer good food

(input)

Solid waste

Accumulation


Consumed food = 0.6 * 50 = 30 kg

Input = output (food) + output (solid waste) + accumulation

50 = 30 + solid waste + 1 total amount of generated solid waste = 19 kg

25% of the solid waste is recycled = 0.25 * 19 = 4.75 kg is recycled

Thus the solid waste send to curb side collection weekly = 19- 4.75 = 14.25 kg.

Characteristics of Solid Waste

- It is the identification of chemical,physical and biological properties of waste.

- Characterization is limited to residential, commercial and some industrial waste.

- It is difficult process due to the limited number of samples, that can be collected

and analyzed, the large number of sources and the heterogeneous nature of

solid.

1- Physical Properties of Solid Waste The main physical prosperities of solid waste are: specific weight, moisture content,

particle size, size distribution and field capacity.

I. Specific weight:

- The weight of materials per unit volume lb/yd3 or kg/m3.

- Each waste component has its own specific weight.

- Compaction process can affect the specific weight, so the specific weight is

reported for uncompacted waste or as found in the container.

- Typical value of specific weight for delivered solid waste in compactor is

296.6 kg/m3(500 lb/yd

3) (Tchobanoglous, et al., 1993).

II. Moisture content:

- Represents the amount of water in the waste.

- This is considered the major parameter in measuring the heat value of the solid

waste, as the moisture content is higher; the lower is the heat or calorific value

of the solid waste.


- Moisture content is measured as the difference in weight for an item wet and

after dried in an oven at 105 oC.

- The typical data for the moisture content is between 15-50%.

-


III. Particle size and size distribution:

- It is an essential term in material recovery especially with mechanical sorting

machines like screens or magnetic separator.

- The average size for individual solid waste components is between 17 -20 cm

(7 -8 inches).

IV. Field capacity:

- It is the total amount of moisture that can be retained in a waste sample subject

to the downward pull of gravity.

- It is important to determine the leachate formation in the landfill (Vesilind et

al., 2002).

2- Chemical Properties of Solid Waste

- It is essential to design processing and recovery options, especially heat recovery.

The main chemical prosperities are ultimate and proximate analysis, fusing point

of ash and energy content.

a) Proximate analysis:

- The determination of the combustible components in solid waste. It includes

moisture content, volatile combustible matter, fixed carbon and ash (Vesilind

et al., 2002).


b) Fusing point of ash:

- The temperature at which ash resulting from the burning of waste at 1100 –

1200 oC (Tchobanoglous, et al., 1993).

c) Ultimate analysis of solid waste:

- The determination of the percentage of Carbon, Nitrogen, Oxygen, Hydrogen,

Sulfur, and Ash.

- Ultimate analysis is used to characterize the chemical composition of the

organic matter in municipal solid waste.

- Determining chemical composition is necessary to achieve the optimum C/N in the

composting treatment of solid waste, or to calculate the heat content (Vesilind et al.,

2002).


d) Energy content of solid waste:

- It is determined by full scale boiler as colorimeter and laboratory bomb

colorimeter or by calculations if the elemental composition is known.

- The moisture content directly affects the energy content ?? why

because portion of the heat within the solid waste will be

consumed to evaporate the moisture. be determined.

KJ/kg or K calori/kg

Average Jordan energy content: 2747 kcal/kg


3- Biological Properties of Solid Waste

- Include the content of the organic fractions in the solid waste except the

plastic, rubber and leather components.

- The main organic fractions are the oil, fat, water soluble substances as sugar

and starch, cellulose, lignin and protein.

- Usually the organic fraction is degradable even though some fractions may

take long time to degrade as lignin (Vesilind et al., 2002).

- Biodegradability of the organic fraction of the solid waste is determined by the

volatile solid content (VS) that is determined at a temperature of 550 oC.

- Degradation of the organic fraction is responsible for most of the odor

produced from the solid waste degradations (Tchobanoglous, et al., 1993).

Documents

Solid Waste Evolution and Concepts p… · 50 = 30 + solid waste + 1 total amount of generated solid waste = 19 kg 25% of the solid waste is recycled = 0.25 * 19 = 4.75 kg is recycled