OPERATION OF AN ATTACHED GROWTH NITRIFYING REACTOR UNDER SHOCK LOADS OF AMMONIA AND ACTIVATED SLUDGE SUSPENDED SOLIDS.

Crankley Point Sewage Treatment Works, Newark, England treats both municipal and industrial wastes. The introduction of new discharge consents establishes an ammonia standard for the first time. Particular industrial wastes pose constraints to comply with this standard, causing highly varied ammonia loads to pass through the works.Severn Trent Services evaluated the TETRA submerged aerated filter (SAF) and deep-bed filter (DBF) technologies to establish their ability to perform under the following conditions:Naturally occurring variations in ammoniaSudden and prolonged spikes in ammoniaWashout from the activated sludge plant.The SAF and DBF technologies coped well under normal diurnal and weekly conditions and responded quickly to sudden high increases in ammonia, maintaining effluent levels for periods of 24 hours and returning to normal levels once shock load conditions ceased.As a result of these trials, Crankley Point Sewage Treatment Works is being extended to incorporate the TETRA SAF and DBF technologies.