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For more information or to book an advertisement in the next feature please contact: Tel: 0845 680 0024 www.hub-4.com Product focus Washing,Screening & Dewatering Plant Water & Silt Management Systems September 2012 Tel: 0845 22 22 386 www.duoplc.com Gallagher invest in second DUO wash plant… pages 2 & 3

Washing, Screening & Dewatering Plant. Water & Silk Management Systems

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Page 1: Washing, Screening & Dewatering Plant. Water & Silk Management Systems

For more information or to book an advertisement in thenext feature please contact: Tel: 0845 680 0024

www.hub-4.com Product focusWashing,Screening &Dewatering PlantWater & SiltManagementSystems

September 2012

Tel: 0845 22 22 386 www.duoplc.com

Gallagher in

vest

in second DUO

wash plant…

pages 2 & 3

Page 2: Washing, Screening & Dewatering Plant. Water & Silk Management Systems

At its Hermitage site, near Maidstone in Kent,where Gallagher's produce aggregates for theconstruction industry for road building, readymix concrete and engineering work aninvestment in a new wash plant has increasedboth throughput and flexibility allowing thecompany to offer more high value products tothe marketplace.

Part of the Gallagher Group, one of the largest privatelyowned, building, civil engineering, quarrying andproperty businesses in Kent, the Aggregates Division ownand operate Hermitage Quarry which is the first Ragstonequarry in history to be worked to modern standards. Thisis particularly demanding due to the nature of thegeology of the 'Hythe Beds', so called because theyoutcrop in the cliffs of Hythe.

Ragstone occurs in bands between 15cm and100cm thick, alternating with a loose materialcalled Hassock. This latter material has in the pastbeen unusable but with modern advances intechnology employing innovative new techniquesthis is now washed and used in such areas asdrainage materials and pipe bedding as well asother specialist products. Whereas a proportion ofthe quarried material in the Hythe Beds was oncewasted, Hermitage Quarry has now been reducedthis figure to below 10%.

The new wash plant supplied by industry leading,specialist washing equipment supplier DUO(Europe) plc of Coventry has been installed toimprove efficiency and production of high valueproducts. Situated in a new part of the quarry theplant has enabled Gallagher's to increaseproduction and produce clean washed materialsthat have a higher value on the market.

The new wash plant uses an existing on-site watertreatment plant; Fintan McKeever, Director at DUO,commented, “From past projects we havecompleted for Gallagher's we recognised thatthere was an issue with the limited on-site watersupply and subsequently designed the new washplant to run at maximum efficiency with low waterusage, specifically the inclusion of a Cedarapidsscreen in the plant design to help the customerovercome this restriction.”

The production process is relatively simple withmaterial fed through a mobile Maxtrak 1000 Conewhich provides tertiary crushing to materialalready part-processed by Gallagher Aggregate'sexisting plant, providing the ragstone feed to theprimary conveyor at 225tph; or alternativelymaterial can fed by wheeled loader into the dumphopper positioned at the bottom of this inclinedconveyor. The hopper and lattice framed feedconveyor were both designed and robustly built byDUO's manufacturing division who are vastlyexperienced in providing highly durable solutionsto the quarrying industry. The conveyor features fulllength galvanised walkways on both sides and isdriven by a motorised drive drum which provideslow maintenance with a lifespan of upto 10,000hours, the additional benefit of this component isits low energy consumption in comparison totraditionally driven conveyors.

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Gallagher'sInvest innew DUOWash Plant

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The DUO Manufacturing conveyor feeds a Terex Cedarapids screen;the 20 x 6 - 3 Deck screen is of horizontal design. The horizontalscreen, which provides a lower, more manageable overall height, usesan oval stroke motion which is considered by many to be the mostefficient screening motion in the industry. This motion moves thematerial across the screening media at a lower travel rate than thatachievable by gravity dependant incline screens. This lower travel rateforces near-size material through the apertures, it also increases thematerials exposure to the high pressured spray; the outcome of thisbeing the production of a more accurately sized and cleaner endproduct. The Cedarapids efficient use of water fits within onsite waterconstraints; the selection of spray nozzles fitted to this screen providesfurther efficiencies in this area. The processed material is stockpiledusing three 65ft Powerscreen radial conveyors which, as with the DUOManufacturing built feed conveyor, are driven by a motorised drivedrum.

The underflow from the Cedarapids is sent to a compact 85tph sandplant which features advanced hydrocyclone technology in the form ofa 'Separator'. This technology provides consistent low moisture contentdewatering of product, irrespective of variations in feed solids contentand without loss of useful fines. The operator has the option to adjustthe quantity of silt in the product to achieve the specification desired.Dewatered sand from the compact plant is then delivered to stockpilevia an additional 65ft Powerscreen radial conveyor.

Once again the DUO capability of being able to provide a highperformance processing plant when needed was a major advantage toGallagher's, who with bigger on-site capabilities can now provide theirexpanding market with clean aggregate.

Andy Bate - Director of Gallagher Aggregates, commented, “AtGallagher we have a long-standing working relationship with DUO.This is the second wash plant they have supplied us, they supplied ourwater management system and their manufacturing division haveundertaken several other projects for us. The decision to use DUO forthis project was not wholly about cost but primarily focused on buildquality & reliability and the ability to deliver on their promises.”

When askedspecifically aboutthe new wash plant,Andy commented further,“The plant gives us far greaterflexibility and has improved the recoveryof high value products. The plant isperforming excellently andintegrates very well with ourexisting operation.”

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Bespoke hopper and feed conveyor designed &manufactured by DUO Manufacturing

Fully integrated with existing processing plant

Terex Cedarapids horizontal rinsing screen & asingle grade sand plant.

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Experience andinnovation - theright combinationCookstown based Bruce Engineeringhave been providing tailor-madesolutions for the minerals industry for inexcess of fifty years. Now the time has come for them to putthat vast wealth of know-how into yoursand and gravel production.The BRUCE WASHING range includesbucket wheel dewatering plants whichmay be perceived as the more traditionalway of recovering sand, however manycustomers still find this the most costeffective solution. Bruce also offer,dewatering screens, washing screens,modular, single and twin cyclone plantsas well as turnkey closed circuit washingand water treatment systems.Sand is a hot commodity in New Zealandand Fulton Hogan decided on a BruceBucket Dewaterer BWD150 to increasetheir efficiency in their sand processingplant. The sand is used mainly forconcrete and is in high demand for theconstruction industry.Fulton Hogan are a large companybased in New Zealand employing 4500people to deliver excellence to their corestrengths of civil construction, surfacing,and infrastructure services. The technicalteams challenge traditional engineeringpractices to deliver innovative solutions.Their screening and washing plantprocesses up to 280tph of raw feed andFulton Hogan are extremely happy withthe Bruce BWD150 and have just placedtheir second order.Project Manager quoted “We were veryimpressed with our first washing plantform Bruce and have just placed thesecond order. Bruce spent additionaltime with us to make modifications toensure we produced the perfect productfor our customers and we can nowproduce sand at a more efficient rate tomeet the demand.” Bruce also have options which go aboveand beyond the average. A range ofstatic and mobile aggregate cleaneroptions such as the BWR/BWL range ofcoarse material washers, which will helprelease sand and stone content fromdirtier deposits. There is also the optionof a trash screen to remove any waste ororganic material from your finishedproducts.

BWD150 Bruce Bucket Dewaterer at Fulton Hogan Quarry, New Zealand. Themost cost effective and efficient way to remove water from sand, clay and silt. Therange is available in 90, 120 & 150tph capacity

Sand produced from the Bruce BWS60TPH Sand Plant

The company has recently had a successful Hillhead show andRWM exhibition at the NEC where they exhibited a Baionicentrifuge silt recovery plant as well as the BWR 300mobile/modular aggregates cleaning system. Bruce can now boast a sales team of five in its UK area ofoperations so should you need a site survey or wish to have moreinformation on products then get in touch.

Tel: 028 8676 3684 Email:[email protected]: www.bruce-eng.co.uk

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The new facility is located at the Dix Pit complex in Stanton Harcourtwhich covers approximately 150 hectares. The site has previously beenused as a sand and gravel deposit and today The Sheehan Group has avariety of industrial and commercial neighbours including a batchingplant and a household recycling centre. In addition to the supply ofsustainable aggregates and construction materials The Sheehan Group isalso a Groundwork & Civil Engineering Contractor as well as beinginvolved with plant hire and waste removal and reclamation.

Maximising material recoveryBefore operating from the Dix Pit complex The Sheehan Group had anexisting recycling facility at Slape Hill, near the village of Woodstock onwhich the lease expires in 2014. This facility employed dry crushing andscreening to process 60,000 tonnes per year of construction anddemolition waste which was primarily applied in low value applicationssuch as cover or general fill. “The enhanced recycling capability that ournew washing plant offers enables us to progress this material up thewaste hierarchy and offer a real alternative to virgin aggregates” explainsTara Sheehan, Financial Controller with The Sheehan Group.

All of the C&D waste material that The Sheehan Group handle is nowprocessed through the new CDE washing plant at Dix Pit with the licencepermitting 100,000 tonnes per year. In addition to the 60,000 tonnes ofmaterial processed at the previous site an additional 50,000 tonnes wasbeing sent to landfill each year as a result of the limited capability of thecrushing and dry screening plant. “Getting the washing plant up andrunning earlier would have saved us sending this large volume of materialto landfill for the last 5 years” says Chris Sheehan. “The advancedprocessing methods that we have introduced maximise material recoverywhen compared to dry processing which is why we fought so hard to winthe right the install the new plant.”

The primary source of feed material for the Dix Pit plant is withinOxfordshire with a smaller amount coming from surrounding counties suchas Buckinghamshire. External hauliers are bringing material from thefringes of Greater London.

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SheehanHaulage invest inrecyclinginfrastructureSheehan Haulage & Plant Hire haveannounced an enhancement of theconstruction and demolition wasterecycling infrastructure in Oxfordfollowing a multi-million poundinvestment in a new wet processingplant from CDE Global.Persistence was the key to success in thisinstance as the result of an extendedplanning and appeals process. TheSheehan Group originally proposed thenew waste recycling plant in May 2006and the plant was finally commissioned inJune 2012. “We knew that there was aneed for investment in more advancedrecycling technology for construction anddemolition waste in the Oxford area andhave fought for the last five years to havethis recognised” says Chris Sheehan,Managing Director of The Sheehan Group.“While we regret the loss of 500,000

tonnes of C&D waste recyclingdue to the planning process weare now pleased to say that thenew plant offers our customers agreatly improved product offerwith a wide range of high valueapplications.”

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The processThe washing plant contains a range ofequipment from the CDE product portfolioincluding a feed system, AggMaxportable logwasher, Prograde aggregatescreens and Evowash sand washingplant. In addition the system employs fullclosed circuit water recycling with theinclusion of the Aquacycle thickener andGHT Filter Press.

As material is delivered to the plant anoverband magnet on the feed conveyorremoves any metals before it is sent tothe AggMax. This involves four stages ofprocessing on a single unit - pre-screening, attrition, trash removal andaggregate dewatering.

The pre-screening stage allows for any -5mm particles to be liberated anddelivered to the sand washing phase.The +5mm aggregate material enters theintegrated Rotomax logwasher and issubjected to a high level of attrition fromthe twin shaft machine. This furtherliberates more -5mm material while alsofloating off any lightweight contaminationat the rear of the unit. This issubsequently dewatered on the trashscreen and while the trash material -plastics, polystyrene, rubber, wood - isdischarged into a bay the -5mm materialand waste water are also sent to theEvowash sand washing plant to maximiserecovery of the sand fraction.

As the scrubbed aggregates aredischarged from the Rotomax they aredelivered to a dewatering screen wherethey are given a final rinse before beingsent to the aggregate sizing phase. Onthis project a Prograde P275 dry sizingscreen produces 4 recycled aggregateproducts - 5-10mm, 10-20mm, 20-40mmand +40mm. The -5mm material iswashed to produce two recycled sandproducts via the Evowash 102 dual sandplant.

The water treatment phase first involves the Aquacycle thickener whichreceives waste water from the Evowash containing the -63 micronparticles. The Aquacycle design allows for high rate settlement of thesefine particles to the bottom of the thickener tank while the recycled wateroverflows to a concrete water recirculation tank before being recycled tothe washing plant. A lightweights removal screen ensures that anymaterial such as polystyrene that has not been captured does not re-enterthe water circuit.

The settled sludge from the Aquacycle thickener is then delivered to aconcrete buffer tank before being sent to the GHT Filter Press tomaximise water recycling. In this instance the filter press is made up of140 plates which press the sludge at extremely high pressure to removethe maximum volume of water. The waste material is then compressed toa filter cake containing 90% dry solids content which is dropped fromthe filter press into a bay below.

The resultsFully operational since June 2012 the Sheehan Group report that thenew washing plant has achieved what was intended of it with all of therecycled sand and aggregate products proving very popular withcustomers. The end uses for the material to date have included pipebedding, drainage material and paving. The recycled sands are beingapplied in concrete manufacture and concrete block making,

Approximately 50% of the material is used by the Sheehan Group on itsown construction and civil engineering projects with the remaining 50%sold to the local private construction market. “We are transportingmaterial within a 25 mile radius when using it on our own projects buthauliers collecting material ex-pit are moving it further than this” explainsChris Sheehan. “All the demand at the minute has come from the privatesector but we are currently tendering with various local authorities in thehope that they will come on board and embrace the use of recycledmaterials on their own projects.”

Expanding on this Tara Sheehan believes that the increased focus onsustainability and ethically sound operations is also having an effect ondemand. “We have noticed among the private sector contractors thatthose operating within the 'Considerate Constructors' scheme have beenvery receptive to the idea of using more recycled materials” explainsTara. “They see it is a way of reinforcing their position as leading theindustry in relation to the sustainability agenda.”

In contrast, the level of interest from the local quarry operators has notbeen as strong. “Several local operators have visited the new plant andsampled material but we don't have any firm commitments to purchaserecycled materials” remarks Chris Sheehan. “Given the business casethat exists for recycled material, not to mention the potential that it offersfor us to protect aggregate supply for the long term I am surprised at thisapproach.”

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Washing, Classifying &Dewatering fromMclanahan CorporationMcLanahan Corporation produces the widest range ofequipment for washing, classifying, dewatering and managingtailings in the aggregates industry. McLanahan provides yearsof expertise in design and manufacturing; additionally, thecompany is able to offer true 'solution driven' processengineering to design a system from start to finish.

McLanahan offers various designs of feeders to deliver the materialto the process, and also manufactures crushers to meet a customer'ssize reduction specifications. After this process, the sand fraction isthan directed to an appropriately designed washing and classifyingsystem. Where needed, McLanahan offers scrubbers, log washersand other feed preparation equipment to liberate clays andcontaminants. Often, cyclones deslime the liberated clays from washplant feed.

Wash plants can be as simple as a Separator™/Dewatering Screenplant to classification into discrete fractions with Hydrosizers™(Recipe Plants) or separation into two products using a classifyingtank. Contaminants, such as lignite, can be removed using the Lites-Out™ Classifier. Final products are dewatered by the traditionalscrew or more typically by McLanahan's Dewatering Screens fordrip free stackable sand.

McLanahan offers Fines Recovery Systems to recover and stockpile(often sellable) fine fractions. The next stage is the use ofMcLanahan Deep Cone and High-Rate Thickeners for recovery ofapproximately 85% of the water for immediate reuse and aconcentrate waste solids (underflow) stream for pumping tocontainment. Recently, McLanahan developed the only U.S.manufactured Recessed Plate Filter Press that takes the thickenerunderflow and results in greater water recovery (filtrate) and 'cakes'of ultra-fine solids as a truckable solid.

Whether it is construction grade sands or specialty industrial sands(glass, frac, sports) McLanahan has the capability to meet the needsof any customer.

To learn more about the equipment and systems [email protected]

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Mogensen has been supplyingvibratory screens and Sizers since themid 1970s for the dewatering ofmaterials ranging from copper oretailings in Zambia to the more usualwashed gravel, stone chippings andother washed, recycled materials in thehome market.

Typical of the latter is the Type SPL800/1750-L186 single-deck screensupplied over the past few years toAggregate Processing Solutions Limited(APS Limited), a part of the Finlay Group,and used to follow Logwasher applications.This type of machine is fitted with apolyurethane deck and is usually installedwith a 5º upward slope to increaseresidence time and ensure maximal waterremoval. The capacity of the SPL800/1750-L186 screen, driven by twoInvicta BL30-18/6 rotary electric vibrators,in a typical gravel dewatering applicationis in excess of 100tph. APS Limited has also made use of largerMogensen dewatering screens, such as themachine shown in the illustration - anintegral part of the APS100, arevolutionary, rapid set-up washing system,which was displayed at the 2010 Hillheadquarry show. It is a type SPL DLS3650/1530 L756 double-deck machinealso fitted with polyurethane screen decks,the upper deck having 12mm perforationsand the lower 4mm. This machine isdesigned for horizontal or inclinedinstallation, and has a drive section withmultiple fixing locations to allow forchanges in the drive angle and hence theconveying rate. Another feature is that thescreen is equipped with stainless steel crosstubes, which may be used as spray bars.Mogensen trash screens are also used inthe APS100.The machines described above form part ofa series of twin-vibrator Mogensen screens,all of which make use of a linear mode ofvibration.

Mogensendewateringscreens

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With the installation of two CDEPROGRADE P2-75, 1.5 x 5.0 metreslong, 2- deck dewatering screens for aScottish Quarry operator, CDEapproached Tema Isenmann to supplyan effective modular screening systemwhich would resolve production issues.

With a feed rate of 430 tph of 20mmmaterial onto the top deck, the requiredunderflow 1 product was specified at 0-1.5mm. This however would createobvious issues with the bottom deckloading of the screens, because the1.5mm modules in the first 3 metres of thescreen would have inefficiently screenedthe 20mm material due to the bed depthat the start of the screen. A second issuewas also identified in the last 2 metres at7mm, which would also be an insufficientarea to pass the remaining 0-6mmmaterial, due to the carry over.

Utilising the proven industry standard -ISEPREN WS 85 Modular System, Tema

ISEPREN WS 85 -Tandem Deckinstallationensures efficientscreening

Isenmann resolved all the issues with the installation of a WS 85 -Tandem Deck system that would allow the 1.5 x 12.00mm polyurethanemodules to screen more efficiently due to lower deck loading.Additionally, a gap in the screen to divert 1.5-5mm material directly tounderflow 2 also successfully reduced the loading on the second half ofthe screen which ensured efficient screening of the 0-6mm product on thesecond half of the screen.

As the most versatile and cost effective modular system on the market theWS 85 - Tandem Deck arrangement in this installation provided severalbenefits:

• Working as a protective deck to increase the service life of theseparation deck

• Working as a relief deck to increase the throughput

• Working as a separation deck to obtain four products in one pass

• A better surface drainage (water) of solids

• Reducing screening costs to a minimum

Based on a proven design concept the benefits of the ISEPREN WS85-Tandem Deck System underline a performance that offers total screeningefficiency even under the most difficult conditions.

Easily fitted to all screening machines the system was installed on-site inthe allocated time frame.

Further information: T: 01327 264227 E: [email protected] W: www.temaisenmann.co.uk

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Terex Washing Systems (TWS)announces the release of its new PlantAutomation & Controls Service (PACS).This service will allow customers toimprove plant efficiency by utilising stateof the art, fully integrated controlsystems for the full range of Terex®Washing and Water Managementequipment.Barry McMenamin, manager of theElectrical Systems team at Terex MaterialsProcessing states: “Over the past eightyears, Terex Materials processing hasestablished a strong team of electrical,electronic and software engineers employingsome of the most experienced and skilledindividuals in the market place. This hasallowed Terex to develop some of the mostadvanced and user friendly control systemsin the industry for our full range of mobileand stationary crushing and screeningplants. This helps our customers achieve themost cost effective and efficient operatingand control systems, whatever their plantrequirements from basic push-button singleplant control to complete large scale multi-plant automation, including radio andtelemetry control and data acquisition.”

Adding to this, Sean Loughran, Product Line Director for the TWSbusiness, said: “With Sand, Ore, Coal and Recycled MaterialWashing all requiring an increasingly sophisticated level of operatorcontrols, bringing a range of equipment into the control sphere - suchas Cyclones, Dewatering screens and Filter Presses along with thesampling and analysis of chemical additive systems - Terex WashingSystems is perfectly placed to offer an unparalleled service of plantautomation.

“This service begins with a simple questionnaire, followed by sitemeetings, requirements gathering and eventually the creation ofFunctional Design Specifications. Once agreed by all parties, the fullcontrol system designs are created including all schematics, Bills ofMaterial and full software files as required for all automationfunctions. TWS also integrates existing plant controls to their systems,including crushing, screening and even third party wash plants.

“We expect this initiative to be a major benefit to our customers anddistributors and allows TWS to offer the complete wash plant solutionfrom concept to commission.”

Terex Washing Systems announces newAutomation and Control Initiative

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Known throughout the industry for static and mobilecrushing plants, Metso Minerals are the leadingglobal provider of solutions, equipment and servicesto both the construction and the mining industries.

Industry-leading solutions embrace an extensive servicesoffering and the latest technology across the fullest fullrange of processing equipment often making Metso thefirst choice for many in these difficult times.

With ever expanding slurry handling solutions productlines, Metso provide numerous ranges of both verticaland horizontal pumps, specifically engineered for themost abrasive of solids handling applications.

Back in September 2007, Pump Engineer magazine firstquoted the phrase “Metso Minerals; the solutionsprovider that tries harder.”

Since then Metso have done what they set out toachieve, increase their market share, and moresignificantly, introduce into Europe the highly successfulThomasTM Dredge pump range.

Following initial successes in Germany, word spread andnow additional dredge manufacturers and operators areselecting the ThomasTM pump as a first choice solutionto their needs.

Italy in particular has proven to be a good market forMetso and the ThomasTM range, where a trulyinternational team effort has assured continued successfor one particular dredge manufacturer and operator inNorthern Italy.

Supported by Metso engineers from Italy, UK andAmerica, Metalmeccanica Strobietto s.r.l. Ozegna (TO)Italy, designed and manufactured what is reported to bethe largest aggregate producing cutter water suctiondredgers (CWSD) in Italy.

Dredger 'Nessie' was commissioned in 2011 andincorporates a Thomas TU46WD, 550 mm suction underwater pump mounted on a modular suction ladderenabling maximum aggregate production at a variety ofdepths. (Fig 1 Pipe from barge to shore.)

Extensively used in North America, the Metso TU46WDdredge pump is of High Chrome white iron constructionhaving a minimum hardness of 650 BHN and a 46”,1168 mm diameter solids handling high efficiencyimpeller. Designed for continuous under waterapplications the bare shaft pump alone weighs in at over11 tonnes.

Like all Metso pumps, basic selection is made usingMetso's in house PumpdimTM selection programme one ofthe most advanced pump sizing tools available today foraccurate pump selection making appropriate allowancesfor effects of solids on head, efficiency and flow asappropriate.

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Metso THOMASTMpump ensures dredgersuccess ......with1200tph of Sand &Gravel

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Fig1.

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PumpdimTM ensures safe and reliable operation withmaximum time between rebuilds, by not only selectingthe right pump for the job, but also considering allmechanical and hydraulic limitations of both pump andsystem.

At the current extraction site where solids are anythingup to 450 mm diameter, the dredger “Nessie” isproducing on average some 1200 tph of solids througha 500 mm discharge line to shore, where excavatorscontinually load the 'washed' aggregate on to trucks fordespatch to various road construction projects throughoutNorthern Italy. (Fig 2 Dredge pump lifted out fortransport and Fig 3 1200 TPH of S&G discharging indraining stockpile).

The CWSD dredgers produced by MetalmeccanicaStrobietto are considered by many as state of the art,innovative machines, specifically designed for dredgingcustomers who want to obtain high production volumeswith reduced operating costs.

Primarily for use in quarries, ponds, lakes and othergroundwater areas where deposits are compacted, orthe presence of silt and clay make conventionalextraction difficult, the modular construction design of theCWSD dredges allows Metalmeccanica Strobiettoengineers to manufacture to order in the minimum oftime, normally around four months.

All dredgers can be adapted for versatility and reliableproduction to suit a variety of applications and dredgedepths, currently ranging from 15 metres to a maximumof 60 metres. (Fig 4 Dredge Pump in transport positionout of the water and Fig 5 Dredge Pump being loweredin working position).

CWSD dredgers and the lighter WSD (water suctiondredgers) cover all likely deposits, ranging in size from8 "(200 mm) up to 24" (600 mm) with slurry flow ratesbetween 900 m3/h and 9000 m3/h.

Designed and manufactured to specific requirements, theCWSD 500 dredger was manufactured exclusively tosupply aggregate in large volumes for an extensive roadbuilding project in the shortest time possible. All targetswere either met or exceeded as road constructioncontinued unhindered.

The dredger, designed and built entirely within theMetalmeccanica Strobietto workshops, took just 4months from order to complete and commission. It iscurrently built in a basic 24 metre version (using four 12metre modules), but the design allows for up to 45metre deep excavation, achieved by the simple fitting ofadditional modular elements.

The submerged Metso TU46WD dredge pump ispowered by an inverter controlled electric motor, withpower being transmitted through a speed reduction gearbox and heavy duty transmission shaft.

Electrical power is supplied via a 15 KV power linefrom the local grid, with on board processing for alllocal services, control equipment and monitoringequipment all controlled by PLC.

The main control cabin contains everything needed tocontrol the entire dredging operation by a singleoperator. All 'visualization' is via the operating panel's17” touch-screen providing the necessary checks andcontinuous GPS positioning system.

Further information is available from both Metsoand Metalmeccanica Strobietto websites, withselected users/engineers free to request copies ofPumpdimTM on the Metso site.www.metso.com/pumpswww.strobietto.com/en

Fig 2 & 4.

Fig 3.

Fig 5.