Response 6: Thanks very much for this comment.
The same trend (Figure 2) was mainly due to the stable removal ability of BAC and UF for organics, causing the removal restriction. The periodic backwash (7days) of BAC caused sometimes the dissolved oxygen concentration of BAC-effluent higher than that of raw water. After the gas scrubbing and the hydraulic backwashing, the dissolved oxygen detection of the effluent was carried out, resulting in the above results for dissolved oxygen. Besides, the t-test was used and proved the significant difference between BAC-Effluent and BAC/UF-effluent. Response 6: Thanks very much for this comment.