Installation and Start-up of First 'Drop In' MABR System for Process Intensification (UK)

Spernal Wastewater Treatment Plant (WWTP) processes wastewater from the surrounding catchment area as well as excess biosolids from satellite plants. Consistently seeking to optimise treatment plant process effectiveness and efficiency, and aware that biosolid loadings will increase in the future, Severn Trent considered solutions that could easily increase the nitrification capacity of a typical activated sludge plant. OxyMem was considered as it promised to upgrade without needing to take the existing tanks off-line. Thus, ten OxyMem membrane aerated biofilm reactor (MABR) modules were installed at Severn Trent's Redditch Spernal site, which became the largest MABR system in the UK. The DuPont OxyMem MABR modules were simply lowered into the anoxic zone of lane 3 over a two-day period and quickly boosted the nitrification capacity of the current process. An additional 43 kgN/d was removed in lane 3, equipped with MABR, when compared to lanes 1 and 2, without MABR, - equalling 2.9 gN/m2.d on average. The best performance was observed when the influent NH4-N load to all three lanes increased to 450 kgN/d :- on this day lanes 1 and 2's effluent ammonia increased to 124 kgN/d, where lane 3 increased only to 71 kgN/d. The difference in the effluent was 53 kgN/d, showing the peak nitrification capacity of the hole hybrid MABR process or 3.6 gN/m2.d.