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Technical Description The objective of flow equalization is to level of the 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 of the 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. Design example: A. Equalization tank for 0.05-MGD plant(50,000 gpd) B. Average hourly flow-(ABF) 0.05 x 1.000.000 = 2,083 GPH 24 C.. ABF percentage for consecutive periods of the typical 24-hour day are as follows: TEM: PERIOD % of AHF 1. 0001-0300 10% 2. 0300-0600 20% 3. 0600-0900 70% 4. 0900-1200 250% 5. 1200-1500 150% 6. 1500-1800 100% 7. 1800-2100 150% 8. 2100-0000 50% D. All flows exceeding average hourly flows must be stored.Tabulate excess flows as follows: PERIODS % Less Sum of now> 100% AHF 100% Hrs Hourly % 4 250 150 3 450 5 150 50 3 150 7 150 50 3 50 Total: 750% E. Equalization capacity requirement = 7.5 x 2,083 = 15,624 gallons or 31 % of average daily flow. F. Aeration requirements: Because flow equalization volume may be contained within the batch reactor, CFM requirements are adjusted as follows: NORMAL DEMAND 0.05 x 250 mQJL x 8.34 x 1000 ft' = 72.23 CFM 1440 FLOW EQUALIZATION DEMAND - 15- 7•H Technical Services Group,Inc.