Custom-built recycling plant handles construction site debris and waste
The diversion of a considerable proportion of the millions of tonnes of building and demolition waste that makes up a large percentage of the material going to landfill in the UK is seen as key factor in meeting national waste strategy targets driven by EU legislation. LAWE features a purpose-built waste handling plant for the processing of construction site debris located in North London
L & B Haulage processes an almost continuous supply of building and construction waste brought to the site on their own tipper trucks and skips, as well as via other transport companies, from the greater London area. The trucks and skip lorries tip waste into the covered stockpiling area and, from there, one of L & B's hydraulic excavators with grab loads the 725 Trommel's large capacity hopper.
The mixed waste is tromelled and screen separated by the Powerscreen machine and conveyed through a picking station for final sorting and thence into various bins. Fines, rubble, timber, ferrous and non-ferrous metals, board and paper all fall into separate concrete bays beneath the conveyor line. The trommel and picking station has been installed at high level in a specially designed and built covered structure which not only allows all-weather operation, but also reduces noise and dust levels, the latter being reduced further by dust suppression systems.
After processing and separating, around 85% of the total materials is reused. The timber is fragmentised for chipboard manufacture; cardboard and paper is baled and sold on to paper processors for pulp; alloys and ferrous metals go on to the metal recycling yards; and rubble is crushed, screened and cleaned for use on temporary haul road construction.
The Powerscreen 725 Trommel in one of many models in the company's wide range. The Powerscreen trommel programme is designed and built for the screening and stockpiling of extracted aggregates, debris and waste products from construction and demolition, wood and green waste, industrial and municipal waste, topsoil and recyclable materials.
The 31.60m² large area rotating cylindrical screen drum measures 1.8 metres diameter x 4.57 metres length and has variable control for maximum efficiency and adaptability for the range of materials that can be processed.
A range of mesh sizes is available, depending on the customer's requirements and the materials to be screened. All Powerscreen trammols are equipped with machined rolled surfaces for support wheels to eliminate vibration. The hopper has a 7m³ capacity with hopper extension. The feed conveyor has a three-ply continuous belt of 1,050mm width and has variable speed control. The two-ply 1,050mm wide collection conveyor, with belt scraper, feeds the front conveyor, which has a 900mm wide two-ply chevron belt.
Power is electrical on L & B's model, although the standard power sources are usually Deutz diesel engines' and all trommel hydraulics are protected by an automatic shut-down system. A conveniently located control panel provides fingertip management of all machine functions.
Powerscreen trommels are available variously in static configuration, wheeled
or as fully mobile crawler-mounted versions.