Used to Useful

A typical configuration has these digesters receiving waste from local industries, dairy farms and waste recyclers. AD Technology takes the waste and generates biogas. That biogas from the digester can then fuel a gas engine to generate up to ~ 5 MWh of renewable electricity. This renewable energy could replace traditional energy use at the local industries, which in turn reduces greenhouse gas emissions, (by the equivalent of tens of thousands of metric tons of CO2 each year), as well as reduces waste odors.

But, the benefits do not stop there. The waste from the AD can be further treated to recover more value. Efficient dewatering – using high speed centrifuges – achieves higher solids (which can be land-applied) and cleaner water (for reuse in the industry). New polymer technology that sustains the high shear in the centrifuge can deliver reuse water containing less than 2% solids, and typically between 0.2 – 0.8%. Cake solids range from 35-45% and can be land-applied on site so there are no hauling costs.

All this can be achieved by reviewing operating conditions, such as bowl speed and speed differential to optimize torque. Polymer dosages need not be very high and can match those used in traditional municipal plants.

By looking to a historically untapped market and by combining advanced technologies – Anaerobic Digestion; Dewatering; Gas Engines; Chemicals – industries (particularly food manufacturers) can find new value in their waste management solutions and create renewable energy alternatives.

http://ch4biogas.com/projects/napoleon-biogas/

http://wst.iwaponline.com/content/41/3/283.abstract