Effect of Aeration Rate on Forced-Aeration Composting of Sewage Sludge and Maize Straw

Abstract

The composting of sewage sludge and maize straw was investigated in forced-aeration composting systems at aeration rates of 0.28, 0.56 and 0.83 l min-1kg-1organic matter, corresponding to pile A, pile B and pile C. The composting temperature in three piles met the hygienic safety criterion, and final electrical conductivity did not exceed the limit value of 3000 μS cm-1. The final NH4+-N content in pile C exceeded the limit value of 400 mg kg-1. The final NO3--N content, cation exchange capacity and germination index in pile B were superior to those in pile A and pile C.