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Technical Description liquor volatile suspended solids(ML,VSS), and consists mainly of microorganisms, inert suspended matter, and nonbiodegradable suspended matter. After a preset time period, the mixed liquor is transferred to the clarifier tank for separation of suspended solids from the treated wastewater. The biological solids are then returned to the aeration tank to maintain a concentrated population of microorganism's to treat new, incoming'waste. 1 DETAILED PROCESS DESCRIPTION Incoming sewage is accepted into the aeration chamber via a mesh receiving basket in which it is subjected to hydraulic comminution bymeans of the composite flow of mixed liquor and air directed through the basket. This allows only small particles to enter the main area of the chamber,while also assuring odorfree operation by underwater breakdown of solids. The reserve solids in the basket also assist in stabilizing the biologic process during periods of low flow. The amount of air required for complete digestion of sewage is lower in the Bio-Pure plant than theoretically required.This is because the operating temperature of the mixed liquor is as much as PC higher than the temperature of incon ng'wastewater, due to the heat exchange from the submerged transfer and aeration pumps and the closed tank design. This higher temperature, plus the floc-colony breakup and reactivation caused by increased agitation, renders the organic material more readily digestible. This enhanced digestibility, in conjunction with the high level of mixed liquor/suspended solids (MI..SS of 3,000-6,000 mg/L), increases groups of facultative organisms which are able to initiate further waste digestion by utilizing some of the chemically bound oxygen present in the mixed liquor. The elevated operating temperature increases the enzyme and biologic activity, thus consid- erably less retention (or residence) time in the aeration phase is required. Aeration chamber residence time for the digestible material is 16 hours and is dependent on the final system batch timing, which is based on effluent testing. ., ,a As the height of the mixed liquor increases in the aeration chamber, a float switch initiates the system microprocessor which, in turn, starts the mixed liquor transfer pump (MILT) and transfers a fixed volume(batch)of mixed liquor to the clarifier. The MLT pump is controlled by time, and the actual programming allows for two or three minutes' pump overrun to overflow the MLT into the weirs, which skims off the scum and other floatables. These floatables are returned to the aeration chamber for reprocessing. Batch time in the clarifier is determined by the amount of time necessary for the remaining bacteria and dead cells(which flock together once deprived of food and oxygen)to settle, thereby separating the supernatant from the sludge. This time period is sufficient to allow flocculation and settling, but is not long enough to encourage an extended anaerobic condition. Average time is 65 minutes. No coagulants are needed, nor are they recommended. Two very common problems in most extended-aeration, small-flow treatment plants are the denitrification of the sludge that occurs in the settling tanks, which causes sludge flotation and subsequent loss over the weir, and surface skimming devices which prevent a quiescent environment which, in turn, prevents efficient settling, thus causing a high amount of suspended solids to be 6