August 28, 2019 @ 11:39 by Steven Hugill
A waste recycling firm is working with academics to give new purpose to a construction and excavation by-product.
Scott Bros. Ltd has teamed up with Teesside University to find alternative applications for its particular brand of unwanted ‘filter cake.’
The company uses a £1 million wash plant to process construction and excavation waste into sand and aggregate for the building industry.
However, 30 per cent of every 20 tonnes that passes through the plant is fine-grained clay-based ‘filter cake’ material, which can only be used as a pond lining clay or inert fill.
To find a use for the material, Scott Bros. Ltd is working with the university’s School of Science, Engineering and Design.
Bosses say the research, which will conclude next summer, is already producing “encouraging results”, with possibilities including its use in the brick manufacturing process, floor screeding and ground improvement.
The work carried out by the university is part-funded by a Government grant and part of the Knowledge Transfer Partnership (KTP) programme, which is designed to help businesses innovate through academic support.
Peter Scott, a director of Scott Bros. Ltd, said: “This sustainable process is creating in-demand building products, but we are determined to achieve zero waste.
“We would dearly love to say we recycle 100 per cent of everything passing through the wash plant into valuable construction material.
“We are 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.”
Scott Bros. Ltd’s wash plant, based 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.
The products are cheaper and reduce the environmental damage caused by the quarrying and production of primary materials.
As part of the research, academics from Teesside University visited the factory to study its processes.
Dr Paul Sargent, lecturer in civil engineering, added: “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 up-scaling from laboratory to full scale.”