A RECYCLING firm is working alongside a team of academics in a bid to solve the problem of unwanted 'filter cake'.

Scott Bros run a wash plant which processes construction and excavation waste into high quality sand and aggregate for use in the building and construction industry.

However, 30 per cent of material that passes through the process is fine-grained clay-based ‘filter cake’ material which can only be used as a pond lining clay or inert fill.

The company is working with experts from Teesside University’s School of Science, Engineering and Design to find a practical and commercial use for the by-product. Possibilities include its use in the brick manufacturing process, floor screeds and potentially ground improvement.

Company director Peter Scott said: “This sustainable process is creating in-demand building products, but we are determined to achieve zero waste. We would dearly love to say that we recycle 100 percent of everything passing through the wash plant into valuable construction material.

“Scott Bros is proud to play an active role in keeping our precious resources in use for as long as possible. Our investment in the wash plant, together with the work we are carrying out with Teesside University, underlines our commitment to the circular economy.”

The research carried out by the University is part-funded by a Government grant and is part of the Knowledge Transfer Partnership (KTP) programme, designed to help businesses innovate through academic support.

The wash plant, situated at the company’s site at Norton Bottoms, near Stockton, is capable of processing between 50 and 70 tonnes of waste per hour to produce both coarse and fine sand, together with three grades of other coarser aggregates.

As part of the research, academics visited the wash plant and studied the processes involved.

Dr Paul Sargent, Lecturer in Civil Engineering, said: “This research project is progressing very well. Extensive laboratory testing has been undertaken in characterising the nature of the filter cake, which enables us to decide how best to bind it together for producing a cementitious product.

“Mechanical strength trials are ongoing and have been producing some encouraging results. We are now in the process of identifying an optimised mixture and manufacturing process for upscaling from laboratory to full scale."