DUO Manufacturing supply new waste sorting plant to W H Malcolm of Glasgow


DUO Manufacturing supply new waste sorting plant to W H Malcolm of Glasgow.

The Malcolm Group is a forward-thinking company that maintains the personalised, hands-on approach of its family-owned background and is the recognised leader in waste management, reuse and recycling of construction and demolition waste in Scotland.

With extensive recycling plants strategically located in the Ayrshire, Paisley and Glasgow areas, the company supplies graded recycled aggregates, topsoil and subsoil to the construction industry Their extensive facilities and long experience give customer's confidence that waste will be disposed in a safe, cost-effective way, minimising environmental impact. Offering skips to allow on-site segregation of waste the company has also increased the potential for recycling and reducing the Landfill Tax burden.

Recently the company has integrated into an existing waste sorting system at their Glasgow site a brand new plant designed, manufactured, supplied and installed by DUO Manufacturing (LJH) of Chantry, Nr.Frome, Somerset.

Designed to handle commercial and industrial demolition, construction and skip waste, pre-sorting is carried out to limit material size to -600mm, weight to 25kgs maximum and also the removal of any combustible or corrosive materials. Any incoming waste that needs to be shredded is fed into the system through a mobile shredder unit which after processing discharges the material into the trommel feed hopper which in turn supplies material onto the inclined feed conveyor.

Manufactured of a heavy-duty stringer type construction the 11.8 m x 1200mm chevron belted conveyor feeds material into the six bay, heavy-duty 2.4 m diameter x 9.4 m long trommel screen which then removes the fines from the material. Inclined at 6 degrees the trommel is mounted on polyurethane tyred wheels which run on solid machined steel roller paths to facilitate smooth running and minimise tyre wear.

With screening elements of 10mm mild steel plates punched to a nominal diameter of 40mm, these are bolted to the trommel frame for ease of replacement/renewal. Additionally, six heavy-duty brushes on spring loaded bearing units complete with hinged frames for ease of maintenance are fitted to clean the screen plates. Supported by a heavy-duty fully welded tower and trestle, rigidly tied and braced for maximum stability, the screen has a nominal clearance height underneath of 2.8 metres.

Access is provided by a 600mm wide catwalk to both sides comprising of a galvanised grip walk type open floor mesh and galvanised handrail tubing supported in tubular standards. DUO also supplied a canvas cover over the top of the trommel drum complete with support frame.

The trommel fines (-40mm) fall through into a collection bay under the trommel screen. Oversize material from the trommel feeds onto the picking belt conveyor; to enable separation of heavy and light materials a blower unit is situated below the discharge of the trommel enabling separation of materials whilst in free fall onto the 1206 Mobile Picking Belt.

Comprising of a backward curve type, high quality, mild steel impeller balance, this air knife allows the heavy materials to drop onto the picking belt whilst lighter materials are transferred via a totally enclosed steel duct to a receiving bay or skip.

Material is then fed onto the tail end of the1206 MPB inclined conveyor section. Fitted with heavy-duty impact bars under the belt at the feed point the 1200 mm wide chevron belted picking belt conveyor is inclined onto a horizontal section for manual picking selection.

Three picking stations on both sides of the belt each consist of 1200mm x 400mm chutes with adjacent mounted emergency stops buttons.

Housed under a canvas canopy with translucent roof lights access to the picking section from ground level is by stairs, mounted at the rear end of machine.

Driven by a 50Hz electric motor drive powerpack the mobile picking station is complete with a single axle on the rear end, complete with air brakes

Material exiting the picking station is then discharged. A further proposed addition is the positioning of an overband magnet that will be fitted between the last sorting station and discharge end, removing any ferrous metals into a bay.

A second blower unit is also situated below the head drum of the picking belt to enable separation of any remaining lights from heavies whilst they are in free fall onto the floor whilst the light materials are transferred via steel ducting to a receiving compaction unit for onward disposal.

All conveyors on the plant are fully guarded to BS 7300 and all machinery is designed and manufactured to comply with the European Directive 98/37/CE.

DUO Manufacturing also supplied a 1206 Mobile Picking Belt for a separate operation on a crushing and screening system processing recycled aggregates on the same site.

David Balmer, Operations and Environment Manager, commented "the build quality and installation of the equipment is first class, undertaken by a professional team at all stages of the work, with backup and spares service friendly and efficient."