Making Laboratory waste pay
Traditionally the waste streams at the Stevenson Laboratory have included dirty water, broken concrete, aggregate and masonry samples. Once tested these samples hold no further use. Other waste by-products include test sample wrappings – plastic, bags and cardboard.’
Stevenson Laboratories have made a concerted effort to minimise waste streams. ‘We capture nearly all of our dirty water in tanks and treat it at our Drury quarry treatment plant. All of the water used in the laboratory to wash and screen aggregate is cleaned and used and reused again in the plant at Stevenson Resources,’ says Stevenson Laboratory Manager, Jayden Ellis.
The aggregates, soil and masonry left over after testing used to be taken to the East Tamaki landfill. Now they are collected by Stevenson Resources at Drury Quarry, which recoups its processing costs by recycling the material into low grade aggregate products. The laboratory’s concrete and masonry waste is added to the crushed block pile at the quarry, which is crushed and sold as recycled crushed block. The laboratory’s waste is effectively turned into viable products to sell.
The disposal of plastic waste, which has been a problem over the past 15 years, has also been reviewed. With a growing demand for raw materials used in production of plastic products, Stevenson Laboratories has acquired recycling bins to collect dirty plastic bags and cardboard boxes.
It is estimated that between 75 and 90 per cent of all of the laboratory’s waste is now recycled or treated.
But the Stevenson Laboratory’s war against waste also targets external sources, with new initiatives aimed at identify as many potential waste streams as possible, that might prove beneficial to Stevenson products.
Projects incorporating waste products with Drury aggregates, could be instrumental in unleashing a new range of products.
‘If we can make money from them, we can look at external waste streams, such as demolition waste, and see what we can reuse. The key is to identify as many potential waste streams as possible that might prove beneficial to our products. We’re still at the testing stage.’ says Jayden
Read more about the sustainability initiatives at Stevenson Resources.