Energy efficiency has become a big issue in wastewater treatment. There are two basic ways to deal with energy in a treatment plant: Use less and make more.
Using less means deploying more energy-efficient equipment and processes. Making more primarily means increasing production of digester methane. Today, researchers are pursuing the ideal of the net-zero-energy wastewater treatment facility.
Is that possible? In theory, yes — because the energy content of wastewater (about 8 kWh for 1,000 gallons) far exceeds the energy required for treatment (0.8 to 1.6 kWh for 1,000 gallons). But is it also feasible in practice? Some experts think so.
Among
