Efficiency times three
“Usum” is Latin for “useful” and that’s exactly what Sven Heinisch sets out to be. A trained construction engineer, he owns and operates a plant in Steigra that makes waste useful again in the form of compost, soil substrate, fertilizer and construction materials. Originally Heinisch ran a construction engineering office together with his wife in neighbouring Naumburg. However, when his father retired, Sven, who was 50 at the time, decided to continue the composting operation his father had built after German reunification. What started out as a sideline turned into a passion. Today, two lines complying with the provisions of Federal Emissions Protection Act work through organic and other waste, and all types of mineral C&D waste. With its eight employees, USUM processes about 35,000 tonnes of input annually, and recently the firm received the RAL quality seal for its compost products.
Making high-quality compost is a challenge for the plant, because the organic waste it receives contains high amounts of contaminants. In among the apples, potatoes and oranges are plastic bags and even the occasional can or glass jar.
“We spend a lot of money each year sorting out the contraries,” says Heinisch. The USUM team manually removes larger items upfront. The subsequent careful prepping with the Crambo and extensive rotting processes ensure that foreign objects aren’t reduced to small pieces. This permits screening with a 20 mm screen cut.
Heinisch: “Screening gives us about 60 volume percent fines and 40 volume percent overs, the latter heavily contaminated with plastic, metal and stones. Our leased Komptech Hurrikan S wind sifter removes about 95 percent of the contraries from that fraction, or about 30 percent of the total.” Currently USUM has to dispose of the screen overflow as well as the contaminants. However, the fees for the screen overflow, which makes up about two thirds of what remains, are now much lower. For Komptech Sales Engineer Karsten Runge, the positive balance is clear: “The costs USUM saves for disposal are estimated to cover all costs for fine compost processing, including contraries removal.”
Rented, used, new
Karsten Runge has assisted USUM for three years as sales rep. In July 2018 Sven Heinisch bought his Maxx drum screen, and a few months ago he purchased a used Crambo 5000. He has been using Komptech rental machines since 2006. “If you work in recycling, you’re going to end up working with the green machines,” laughs Heinisch. He uses the Maxx both for compost preparation and for making lime fertilizer. In 2016 USUM started processing ash from untreated wood in order to make certified organic lime fertilizer for agriculture. “We can now reclaim or reuse everything that comes in. The slag removed from the fertilizer is used as a concrete additive or for roof greening,” he says. His passion for sustainable action is clearly evident. Heinisch set up a cogeneration plant in order to make electricity from the landfill gas that is still given off by the sealed landfill under his site. The energy from it and solar modules on the machine hall roof power USUM’s administration building and electric cars.