In order to determine the empirical constants for the trickling filter design equation, a pilot plant study was conducted with 10-ft deep pilot-scale trickling filter having sampling taps at 2.5-ft intervals. The pilot system was fed with the same industrial wastewater. Effluent concentrations were measured for hydraulic loadings of 0.1, 0.2, and 0.3 gpm/ft2 with no recycle at 20oC. The results of the pilot plant study are shown in the following table:

(a) Determine the constants, [k As] and n values. ([k As] are often combined as one constant value).

(b) Determine the effluent BOD5 concentration of an 8-ft full scale system, operating at a hydraulic loading (Q/A) of 0.18 gpm/ft2 (with no recycle). Influent concentration is 150 mg/L BOD5 and the operating temperature is 20oC.

Depth (ft) Q/A = 0.1 Se/So Q/A = 0.2 Q/A = 0.3 0.74 0.61 0.37 0.23 0.7 0.49 0.55 0.41 0.34 0.14 0.24 0.30 Depth (ft) Q/A = 0.1 Se/So Q/A = 0.2 Q/A = 0.3 0.74 0.61 0.37 0.23 0.7 0.49 0.55 0.41 0.34 0.14 0.24 0.30