Optimising operations for maximum productivity
Founded in 1996, Southampton based Waltet Materials Limited offer a full range of commercial and domestic ethical waste disposal, recycled aggregates, top-soils, and grab & tipper hire services. Over time the company has evolved into one of the most innovative and successful recycling companies in the South of England, employing 120 people.
The Waltet Group is structured around three key operating businesses; Waltet Recycling Limited operate two recycling centres in Romsey and Alton that produce high quality aggregates and soils for commercial and domestic construction projects throughout Hampshire and the surrounding counties. With a philosophy of continual investment in the latest machinery, the company have made recent investments at the Romsey site where McCloskey Equipment have installed a new MWS Equipment Aggstorm™ 80 modular plant, alongside a CSP12-2 compact sand plant, and complete water & silt management system.
The AggStorm™ 80 is a modular plant designed to treat clay bound materials and improve the cleanliness of the final aggregate product, allowing for a much wider use of the final material. Design to work within multiple processing sectors including natural aggregates and CD&I, the equipment has been manufactured with the operator firmly in mind offering large maintenance walkways, maintenance access areas and large access doors across the hull for easy clean out and changing of the log washer blades.
The AggStorm™ produces cleaner material while offering the customer the most advanced screening equipment on the market. It consists of multiple pre, post and trash screens. A wide hull and two spiral axle shafts running in sync with changeable blades which generates an intensive scrubbing action through the feed material creating ‘stone on stone’ attrition to clean the aggregate. The changeable blades come in various options including AR500, cast manganese and alloy steel.
The Compact CSP12 is a modular sand recovery unit which is designed to be both cost and energy efficient. The cyclones remove clays, silts and slime from sand and bring it into specification. It offers exceptional performance, with a 12 x 5 dewatering screen and producing one or two grades of sand. It offers a self-regulating cyclone tank complete with built in float system and anti-turbulence sections. With unrivalled access to all essential areas, customers are able to monitor the plants performance and make adjustments as required.
Custom water treatment plant
A custom water treatment system has been paired to the plant, incorporating an 8m diameter thickener, an overhead beam filter press and the new, innovative sludge and clarified water storage and pumping system. Designed to operate at 80tph, the new plant is producing five products; two sands and three grades of aggregate, to BS specifications which are sold to construction projects within the county.
The plant process
All incoming waste material, C&D, muck, and excavation waste is delivered to the site by lorry and initially fed through a scalping screener. Ken Rothery, Washing Division Manager for McCloskey Equipment, said:
“Material is fed into the loading hopper and up the inclined conveyor, under a magnet and then onto the primary singledeck pre-screen. Fitted with 3mm decks this removes as much sand as possible to minimise any sand going into the log washer. “All the +3mm material then feeds through the log washer and all the sand from the pre screen is collected in the sump below along with any sand from the product screen. A trash screen off the back of the log washer collects any lightweight contaminants such as polystyrene, plastics and wood.
Ken, commented further, “A further innovation was the installation of a digital readout on the sand plant. This simple, yet effective addition, provides operators with a constant, clear insight of the performance of the plant, enabling them to continually optimise operations for maximum productivity.” The plant incorporates five stockpiles including a sharp and a fine sand (0-2mm and 0-4mm) and three aggregates at 10mm, 20mm and +20mm. The latter is presently sized up to 80mm which can be changed as commercial imperatives dictate, allowing for more product flexibility, by changing the screen media.
Source: Hub 4, Issue 67, March/April 2021