Laserfiche WebLink
<br />10 | Final Report Bay Area Clean Water Agencies | City of San Leandro <br /> Potential impact on ability to reduce nutrient discharge loads? Remove more nutrients <br />in the process by keeping flows to the FFRs consistent. <br /> Result from analysis: The nutrient removal benefits were marginal as the FFRs are heavily <br />loaded. <br /> Recommendation: Do not carry forward. <br /> <br /> Optimization Strategy 3: Operate the aeration basins in series to control solids distribution <br />issues between the two basins and to facilitate ammonia and total nitrogen removal. The first <br />train would be retrofitted to operate as an anoxic zone. <br /> Is it feasible? Yes <br /> Potential impact on ability to reduce nutrient discharge loads? This strategy could <br />successfully reduce the year round ammonia/total nitrogen discharge load. <br /> Result from analysis: This strategy will address solids distribution between the two trains <br />and assist with ammonia/total nitrogen load reduction. An extra blower is required to meet <br />the additional demand associated with nitrification. The extent of total nitrogen load reduction <br />will depend on the return activated sludge pumping rate. There are concerns with the <br />secondary clarifiers to handle additional solids loading. <br /> Recommendation: Carry forward. <br /> <br /> Optimization Strategy 4: Operate the aeration basins in step feed mode to reduce solids loading <br />on the secondary clarifiers and enhance total nitrogen load reduction. This strategy is predicated <br />on implementation of Optimization Strategy 3. <br /> Is it feasible? Yes <br /> Potential impact on ability to reduce nutrient discharge loads? This strategy could <br />successfully reduce the year round total nitrogen discharge load. <br /> Result from analysis: This strategy would reduce solids loading on the secondary clarifiers <br />to a level that would not require additional secondaries. Additionally, this strategy builds upon <br />the total nitrogen load reduction in Strategy 3. The extent of total nitrogen load reduction <br />beyond Strategy 3 will depend upon the step feed distribution and would require additional <br />analysis. <br /> Recommendation: Carry forward. <br /> <br />Strategies 1, 3, and 4 could reduce ammonia, total nitrogen, and total phosphorus loads. The <br />recommended strategies are shown with the process flow diagram presented in Figure 4-1. A <br />description of each strategy and the evaluation results are presented thereafter. It is noted, however, <br />that recommended modifications for optimization may impact the plant’s treatment capacity. Thus, <br />any changes for optimization should be considered an interim solution. <br />The capital and operational elements of the recommended optimization strategies are shown in <br />Table 4-1. <br />