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Technical Description Unlike a conventional flowthrough clarifier, where the surface area must be large enough to allow L particles to settle downward in a constantly moving stream,the batch clarifier provides particle settling under completely static, quiescent conditions. This method is more efficient and economical than meeting the need in flowthrough systems for greater surface areas with increasing flow rates at larger Lcapacities. With the batch process,the static clarifier does not require this larger surface area;therefore,in design, the batch clarifier volume capacity is equal to the mixed-liquor volume, or batch, to be transferred. Surface settling rates (SSR) do apply, however, but only on a batch-by-batch basis. SSRs are based upon flow in static conditions and are thus accurate for the 24-hour period flow. The Bio-Pure batch process is unique in that longer retention times are not required to do the accurate sludge volume results obtained in the standard SSV-30 and SSV-60 tests..By staying within those basic design parameters of SSR per batch, the static condition of the batch clarification process is directly comparable to settlometer readings. Complete control of the entire process can be based upon the SSV-30 and -60 tests. If the sludge flocculates well and settles rapidly, it is possible to reprogram the system controlling microprocessor (PC) to allow for automatic sequencing of the batch cycle based upon current biomass conditions within the treatment plant.This change can increase or decrease aeration detention and the subsequent clarifier cycle surface settling rate. The clarifier has a dual-weir system for removal and return of floatables to aeration. The weir system is sized using hydraulic returnisurface area(square feet). One hundred percent of all weir wastewater is returned to aeration and thus is contained within the internal detention time ofthe treatment process. Provisions are made to ensure that any residual floatable scum is not transferred into any downstream process by SNT pump elevation control. FLOW EQUALIZATION Widely fluctuating influent flow rates are typical at nearly all wastewater treatment plants. This fluctuation can result in a loss of treatment efficiency. With higher degrees of treatment constantly being required, some method of flow equalization is a design necessity. The objective offlow equalization is to level offthe daily flow variations in order to achieve a constant, �. batched flow rate at the downstream treatment process steps. This is accomplished by storing influent which is in excess ofthe daily flow-rate average,and then discharging it to the system when the influent flow rate is less than that average. By achieving this objective, overall treatment plant efficiency is dramatically improved. Several methods are available for determining equalization volume;all require generating a daily flow pattern record. If possible, this should be based upon actual plant data. If actual flow data are not available, which is frequently the case, existing communities, developments, institutions, etc., with similar flow characteristics should be studied. r 15