IOQ & CIHT Joint Meeting February 13 th 2012
Mel Taylor & Paul Davis Mobile Aggregate Washing Plant Presentation
1 st Generation Washing System…
1 st Generation Washing System… it works!!!
2 nd Generation – Lincoln April 2006
2 nd Generation – Lincoln April 2006
2 nd Generation – Lincoln April 2006
3 rd Generation – Redditch November 2007
3 rd Generation – Redditch November 2007
4 th Generation – Mobile Log Washer October 2009
4 th Generation – Warrington January 2012
4 th Generation – Warrington January 2012
4 th Generation – Warrington January 2012
Overview schematic of the washing process
Stage 1 – Load feed material onto the live head of the mobile washing plant This removes any oversize and large foreign matter prior to washing and screening
Stage 2 – The material leaving the hopper passes beneath a magnet prior to entering the log wash This removes any ferrous matter from the material to be screened – the ferrous material extracted may in turn then be recycled
Stage 3 – The material in the log wash is severely agitated during the first part of its washing process
Stage 3 – Rubbish leaves the Trash Screen of the log wash after the first stage of the washing
Stage 3 – Rubbish leaves the Trash Screen of the log wash after the first stage of the washing
Stage 3 – Material exits the water bath of the log wash after the first stage of the washing
Stage 3 – Material passes beneath the spray jets High Volume water (70,000 litres per hour) is forced out of the jets, facing against the direction of flow of the material, increasing the effectiveness of the wash cycle
Stage 4 – the washed chippings are discharged to the screener to be sized as required by the client
Stage 5 – The screener is designed to produce two sizes of clean surface dressing quality chippings 10mm and 6mm chippings are produced – though deck sizes can be specified to produce other sizes (subject to suitable feedstock)
Stage 6 – The dewatering screen produces a recycled ‘sharp’ sand This processes all of the <3mm material from the washing plant
Stage 6 – The dewatering screen produces a recycled ‘sharp’ sand This processes all of the <3mm material from the washing plant
Stage 6 – The dewatering screen produces a recycled ‘sharp’ sand
Stage 6 – Typical grading for the recycled sand
Stage 7 – The dirty water from the washing process goes to the water recycling plant to be thickened before passing to the centrifuge
Stage 8 – The water in the water recycling plant is now crystal clear for reuse in the washing system
Stage 9 – The thickened material (<60 micron) silt and water passes to the centrifuge plant
Stage 9 – The thickened material (<60 micron) silt and water passes to the centrifuge plant This produces dry cake from the silt and produces clean water that is fed back into the water recycling plant for final processing and reuse
Stage 9 – The dry cake exits the centrifuge plant
Example Feedstock
Example Feedstock
Example Feedstock
Example Feedstock
Finished Product
Finished Product
Finished Product
- Increased compliance with Local Authority recycling targets - Reduce Waste from Resurfacing Operations - Increased Sustainability by reducing demand for Quarried Aggregates - Reduced “Carbon Footprint” by reducing HGV journeys - Substantial Cost Savings Advantages of Recycling:
Cost Savings Achieved By: - Reducing the quantity of Quarried Aggregate purchased - Reducing the number of long-distance HGV journeys - Recycled Aggregates not subject to the £2 per tonne Aggregate Levy - Reduce the requirement to dispose responsibly of the excess chippings from the original surface dressing process
Some advantages of our system: - MOBILE – comes to your location - COMPACT – can be operated in relatively little space - ENCLOSED SYSTEM & complete water recirculation Eliminates the need for huge settlement lagoons Minimises the amount of fresh water required - PRODUCES 2 SIZES OF CLEAN CHIPPINGS And additionally a recycled washed ‘sharp’ sand for reuse or resale
Some additional uses of our system: Add value to stockpiles of Recycled 6F1 and 6F2 material Produce washed drainage materials including: Recycled pipe bedding (20mm & 10mm) capable of certification to BS EN Recycled sharp sand capable of certification to BS EN (subject to suitable feedstock and correctly specified screen meshes) Thus reducing reliance on quarried gravels and sands – increasing sustainability
Sustainability Case Study - County uses 30,000 tonnes of chippings annually - County recycles 3,000 tonnes p.a. (i.e. 10% of annual requirement) - Recycling saves approx 56,033kg of CO2 per year
Sustainability Case Study Haulage of 3,000 tonnes of New Chippings from Quarry to County (approx 144 miles away) = 103 loads of New Chippings = 19,204 litre of diesel 2.85kg of CO 2 per litre) = 54,904kg of CO 2
Sustainability Case Study Recycling of 3,000 tonnes of reclaimed chippings within the County (approx. 190 miles from SE Davis & Son) = 5 lorry loads of plant & equipment = 9 return journeys = 2,604 litres of diesel = 7,421kg of CO 2 54,904 – 7,421 = 47,483kg CO 2 SAVING
Sustainability Case Study Additional Carbon Saving from Recycling: Each tonne of material recycled used 1 litre less fuel than processing virgin stone. So processing 3,000 tonnes gives a further 8,550kg CO 2 SAVING
Sustainability Case Study Hampshire: Over the last 3 years processed 15,857t Estimated saving 352,476kg CO 2 Norfolk: Over the last 5 years processed 13,457t Estimated saving 257,931kg CO 2
Improved Water Flow Into Lamella Plant Improves Settlement
Washing Recycled Hardcore
Washing Recycled Hardcore
Washing Used Rail Ballast
Our Washing Ethos
Our Washing Ethos
Satisfied Customers:
Award Winning:
Bespoke Mobile Washing Solutions
…thank you for listening