The effect of organic loading rate on granular SBR was investigated. When the organic loading rate gradually reduced from 1.8 kg/(m3·d) to 1.575, 1.125 and 0.67 kg/(m3·d), the characteristics of granular sludge changed greatly, including disintegration of granules, washout of sludge, reduce of granulation rate and settleability of granule, shift of granule shape from regular sphericity to different shapes of asteroid and bacilliform and the increase of color deepness. The granular SBR system reached COD and TP removal rates were about 90% and 70%, respectively, which were not influenced by the reduce of organic loading rate. However, the simultaneous nitrification and denitrification could be greatly influenced by organic loading rate reduce. When organic loading rate reduced from 1.8 kg/(m3·d) to 0.67 kg/(m3·d), the removal rates of ammonia and TN decreased 45% and 40%, respectively. |