SRM, one of Europe's largest waste disposal companies, has developed a process that enables it to accept organic-containing solids and sludges in bulk and turn them into a fuel for use in cement kilns.
The final phase of the Landfill Directive now often prevents such material from being sent to landfill sites.
Although SRM is well able to handle hazardous solid wastes in drums it is not always practical for customers to supply them in this way; the ability to accept material in skips and tipper vehicles makes the new solids handling plant a welcome additional solution.
The solids handling plant has been designed and built by SRM's own research and development and engineering teams. The type of material it can accept includes filter cakes, vehicle paint shop sludges, centrifuge wastes, tank bottoms and oily sludges.
The very high temperatures in a cement kiln - over 1450oC - ensure that all organic materials in the fuel, called Cemfuel, are completely and safely destroyed.
Material is analysed on arrival at SRM's plant at Heysham, UK, and discharged into a large hopper. From there it is transferred via a screw feed mechanism into a dispersion vessel containing a mixture of carrier solvents - themselves derived from wastes - and an additive that helps break up the solids into suspendable particles.
It then passes through a macerator into an agitated storage tank before being recirculated through the macerator and dispersion vessel. The process is repeated until the mixture is stable enough to be sent into the Cemfuel blending system.