101 Solved Environmental Engineering Problems - Softcover

Über die Autorin bzw. den Autor

R. Wane Schneiter, PhD, PE, DEE, is Professor of Civil and Environmental Engineering at the Virginia Military Institute and a Diplomate of the American Academy of Environmental Engineers. Among his other publications is "Environmental Engineering Practice PE Exams."

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Sample Problem:

Municipal solid waste is being evaluated for composting with thickened waste activated sludge, The city generates 300,000 kg of solid waste daily, 32% of which is compostable. The discarded moisture content of the solid waste is 38%, and the waste C:N ratio is 12:1. The waste activated sludge is thickened to 18% solids, and the C:N ratio of the solids is 90:1.

(1) How much sludge must be mixed with the solid waste to produce a C:N ratio of 30:1?

(A) 22,000 kg/d (B) 29,000 kg/d (C) 220,000 kg/d (D) 290,000 kg/d

(2) If the C:N ratio of 30:1 is satisfied by the sludge, what is the resulting moisture content of the mixture?

(A) 24% (B) 30% (C) 56% (D) 69%

(3) How much water must be added or removed to bring the moisture content of the sludge-solid waste mixture, blended to meet the C:N ratio of 30:1, to 60%?

(A) add 120,000 kg/d (B) add 9,000 kg/d (C) add 13,000 kg/d (D) remove 28,000 kg/d

(4) What classification best describes composting?

(A) mesophilic aerobic (B) mesophylic anaerobic (C) thermophylic aerobic (D) thermophylic anaerobic