40 CFR 417.152: Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

Except as provided in §§ 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT):

(a) For normal operation of spray drying towers as defined above, the following values pertain:

Effluent characteristic Effluent limitations

Maximum for any 1 day Average of daily values for 30 consecutive days shall not exceed—

Metric units (kilograms per 1,000 kg of anhydrous product)

BOD5 0.03 0.01

COD 0.15 .05

TSS 0.03 .01

Surfactants 0.06 .02

Oil and grease 0.015 .005

pH (1) (1)

English units (pounds per 1,000 lb of anhydrous product)

BOD5 0.03 0.01

COD 0.15 .05

TSS 0.03 .01

Surfactants 0.06 .02

Oil and grease 0.015 .005

pH (1) (1)

1 Within the range 6.0 to 9.0.

(b) For air quality restricted operation of a spray drying tower, but only when a high rate of wet scrubbing is in operation which produces more waste water than can be recycled to process, the following values pertain:

Effluent characteristic Effluent limitations

Maximum for any 1 day Average of daily values for 30 consecutive days shall not exceed—

Metric units (kilograms per 1,000 kg of anhydrous product)

BOD5 0.24 0.03

COD 1.05 .35

TSS 0.30 .10

Surfactants 0.45 .15

Oil and grease 0.09 .03

pH (1) (1)

English units (pounds per 1,000 lb of anhydrous product)

BOD5 0.24 0.08

COD 1.05 .35

TSS 0.30 .10

Surfactants 0.45 .15

Oil and grease 0.09 .03

pH (1) (1)

1 Within the range 6.0 to 9.0.

(c) For fast turnaround operation of a spray tower, the following values pertain: The maximum for any one day when the number of turnarounds exceeds six in any particular thirty consecutive day period shall be the sum of the appropriate value below and that from paragraph (a) or (b) of this section; and the average of daily values for thirty consecutive days shall be the value shown below multiplied by the number of turnarounds in excess of six and prorated to thirty days plus the appropriate value from paragraph (a) or (b) of this section.

Effluent characteristic Effluent limitations

Metric units (kilograms per 1,000 kg of anhydrous product)

BOD5 0.02.

COD 0.09.

TSS 0.02.

Surfactants 0.03.

Oil and grease 0.005.

pH (1)

English units (pounds per 1,000 lb of anhydrous product)

BOD5 0.02.

COD 0.09.

TSS 0.02.

Surfactants 0.03.

Oil and grease 0.005.

pH (1)

1 Within the range 6.0 to 9.0.