Construction of a pilot scale biological reactor for the removal of Nitrogen from the sludge dewatering effluent at a wastewater treatment plant.
Sludge dewatering effluent (SDE) is a small waste stream from sludge dewatering and digester processing in wastewater treatment plants (WWTP). SDE is rich in ammonia and when returned into the Activated Sludge (AS) process it can contribute 10-20% of the total N-load. The SDE stream reduces the overall nitrogen removal capacity and represents a significant operational cost. Research has proven that this NH3-rich waste stream should be treated separately and one of the most suitable technologies available is an autotrophic microbial process where some groups of bacteria can oxidise NH3 to N2 under anaerobic conditions using NO2 as the electron acceptor.
Hydramet supplied, manufactured, installed and commissioned the pilot plant on a transportable skid. The plant was supplied complete with storage and balancing tanks, a sequencing batch reactor with aeration and mixing. All associated pumps, piping, instrumentation, valves, electrical panels were also supplied pre-installed and tested on the skid, including a control room.