Zhang Zhi-bin, Zhao Jian-fu, Xia Si-qing, Liu Chang-qing, Wang Xue-jiang
College of Environmental and Municipal Engineering, Shandong Jianzhu University, Ji'nan 250101, China.
Huan Jing Ke Xue. 2007 May;28(5):993-6.
Zeta potential, particle size distribution and molecular weight distribution of dissolved TOC were studied to elementarily disclose the mechanism of the chemical-biological flocculation (CBF) process to treat municipal wastewater. Chemically enhanced primary treatment (CEPT) process and primary sedimentation tank process were taken as the parallel-compared wastewater treatment processes. The experimental results show that under the same dosage, Zeta potential of the CBF process effluent is equal to that of the CEPT process, which indicates that flocculant in return sludge does not change the stabilization of particles in CBF reactor, and the biological flocculation is the key reason for CBF is superior to CEPT. In CBF process, good removal results are achieved for particles >10 microm and dissolved TOC with molecular weight >6 ku by chemical dosage, and biological flocculation can not only promote the removal of particles >10 microm and dissolved TOC with molecular weight >6 ku, but also have high capacity to remove small particles and dissolved TOC with small molecular weight, with the results that particles >3 tpm are removed completely and TOC with molecular weight of 2-6 ku are removed by 42.5% .
