Disposing of excess sludge – the organic remnants of the wastewater treatment process – is a significant economic and environmental challenge for anyone who operates a wastewater treatment plant. The facility needs to treat the wastewater and then remove the biosolids. What if the sludge was not an irritation and instead became a valuable part of the facility’s resource recovery?
Anaerobic Digestion has played a key part in turning wastewater treatment plants (WWTPs) into water resource recovery facilities (WRRFs). The byproduct traditionally called “waste gas” is used as biogas - a renewable, clean, green energy source. Some facilities have been able to generate enough to put renewable natural gas (RNG) into a pipeline and/or send power back to the grid.
Once considered to be ordinary and mundane, wastewater treatment is becoming a recognized contributor to the green technology movement. It’s a rising star in the resource recovery world with the adoption of one key ingredient – algae.
Not every utility that cleans wastewater views itself as a wastewater treatment plant.
“Some utilities have started making the shift from saying ‘we make clean water’ to saying ‘we recover resources from water,’” said Matt Williams, an anaerobic digestion/biosolids expert from WesTech. “They are seeing themselves as water resource recovery facilities.”