Table 7131 Industrial Facility Daily Flow Profile

Total Flow, Phenol Levels,

1 377.44 45

2 471.46 393

3 411.96 421

4 254.35 433

5 350.64 683

6 464.19 822

7 339.29 123

8 624.52 467

9 569.57 682

10 47.15 732

11 420.13 398

12 238.46 541

13 553.42 868

14 487.81 558

15 241.18 656

16 562.75 329

17 272.52 822

18 229.83 771

19 237.55 613

20 348.47 400

21 134.44 821

23 143.98 160

24 610.90 214

25 97.65 670

26 398.78 362

27 560.94 303

28 253.44 245

29 574.11 120

30 525.06 251 Average daily 360.59 (0.25 m3/min) 463 Minimum 0.00 0 Maximum 624.52 868

a dramatic effect on downstream processes. An example of this variance is the phenol levels in an effluent stream.

The following steps should be applied to the design of an intermittent flow diversion system.

Step 1: Determine the frequency and duration of the variance to be diverted (to design of the equalization basin) Step 2: Calculate the controlled release rate of the diverted flow to maintain normal operation. Step 3: Use the diverted volume to calculate the surge basin volume to maintain continuous flow to the treatment facility.

Step 4: Verify that the equalized flow meets discharge limits.

As stated earlier in this section, data collection and system profiling are keys to an effective design for this type of equalization system. An effective system is automated based on electronic monitoring of the stream, with diversion occurring as necessary. Three examples of this tech nology are pH sensors to monitor pH for excursions, online gas chromatographs to monitor phenol excursions, and conductivity sensors to monitor TDS. Variations of these parameters can cause substantial damage to biological systems or receiving waters (especially when only primary treatment is used).

For example, in Table 7.13.1, the phenol levels vary substantially from day to day because of variance in plant operation. With the variability of plant operation, diverting the flow at this facility to prevent violation, and bleeding the diverted flow back as concentrations allow is necessary.

The phenol level in Table 7.13.1 shows 24 hr composite samples with a discharge limit of 500 parts per billion (ppb). Further analysis of individual samples indicates that the problem was generated during two periods over the course of the day, lasting about 3 hr each. Also, during this time frame, flow rate increased to 0.473 m/min.

Therefore, the total volume to be diverted is calculated as follows:

Vd = FDTDfDk 7.13(2)

where:

0 0

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