U.S. and Canadian firms are at the forefront of changing perceptions of wastewater not being viewed as something to dispose of, but a valuable resource.... Imagine the day when a wastewater treatment plant is actually producing electricity that can be sold back to the grid. Imagine developing technologies so that your plant becomes a biorefinery that assists in the reduction of carbon footprints."
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| Ostara's Pearl process uses a controlled chemical precipitation process in a fluidised bed reactor |
His enthusiasm is infectious and his plea for a fundamental rethink in the way we approach water and waste is as refreshing as it is heartfelt. And nowhere is this more apparent than when he launches into a detailed description of Kruger's new thermal hydrolysis product, its patented Exelys DLD process, the long-term goal to turn a wastewater treatment plant (WWTP) from an energy consumer to an energy producer, while minimising waste disposal costs at the same time.
Hidden energy
The secret of Kruger's method is to use the energy contained in the sludge effectively. First, in a digester, where the gas developed can be used as energy. Treated sludge is then introduced into an Exelys plant where it is hydrolyzed under high temperatures and pressures. This in turn makes complex carbon chains in the sludge available for conversion to biogas energy, thus enabling the plant to produce from 30% to 40% more biogas than digestion alone.