Cold extrusion is playing an ever greater part in recycling of waste plastic, and the Department for Business and Enterprise is sponsoring research into development of the machinery necessary for such work.

Engineers at Bradford University have built a pilot plant and are running a series of trials with different processes, feed plastics, additives, and final products. Leader of the project, Dr Raj Patel explains:

“We started out comparing cold extrusion and warm extrusion, in which the material is heated prior to processing, and quickly realised that cold extrusion was more suited to recycled plastic. Our process now is to granulate the recycled materials to a consistent size, mix in binders as appropriate to basically, glue the particulates back together, and cold extrude it into sheets or blocks.”