The problems with mixed waste are widely known. The separation of streams, for example food waste and plastic bags, cutlery, and packaging, is currently impractical. The processing of mixed waste is quite possible and the technology for doing so keeps improving. In addition to simply incinerating it, there are ways now to use water steam, pressure and elevated temperature, to produce energy and also oils etc. from waste.
Still, there is room for improvement. There is no good solution to avoid formation of dioxins and other toxic substances. Finally, the plant for these processes is typically large and expensive. It is common that waste gets sent to a different country for processing. A UK university spinout is working on the problem jointly with universities and machine builders in Japan. The results are pictured below. They have invented a catalyst that turns mixed organic waste into carbon. The process is more energy efficient than the ones on the market. It runs at below 200 degrees. Suddenly, it has become feasible to treat waste on-site at organisations large and small. There are no health or safety hazards. The two models take from 100 kg to 24 t of waste per day. They work in continuous and not in batch mode which makes them quite user-friendly. The reaction works particularly well on waste largely composed of food waste, with packaging and other plastics in the mix. The product is carbon (Picture 2) that can be sold off. There are plenty of processors who turn it into briquettes, activated carbon, cokes, fillers, plastics. This solution has won recognition and awards from amongst others, the Solar Impulse Foundation, and they have already sold one unit and the catalysts to a food company in Japan. The UK company will remain as the supplier of the catalyst. As the innovation spreads, the manufacture of the equipment can be licensed from the Japanese partner. Commercial agreements with technical assistance are sought with waste management companies, catering and events organisers. The waste may come from food and agritech industries, sludge, local government etc. Some technical assistance will likely be needed. The UK company will review the composition of the waste stream. If it is not well understood, analysis will be agreed on to check the safety post-installation.
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Fuente: EEN