Abstract：Biochar and AlCl3-modified biochar were prepared by using corn stalks as materials to enhance the dewatering of the sludge. The performances of these two biochar for the enhancement of the dewatering of the sludge and possible enhancing mechanisms were discussed. Results showed that SRF, MC, SV30 and CST of the sludge were decreased and YN was increased after conditioned by the two biochar, indicating higher sludge dewaterability. Furthermore, dewatering of the sludge conditioned by the AlCl3-modified biochar was significantly better than that conditioned by the biochar that without modification. Especially, when the dosage of the biochar modified by 3mol/L of AlCl3 solution was adjusted to 3g/L, SRF, MC, SV30 and CST were decreased to 1.3×1012m/kg, 81.9%, 78.6% and 35s, respectively, YN was increased to 17.8kg/(m2·h). For the enhancing mechanism, on the one hand, after conditioned by the biochar, certain skeleton structures were formed in sludge cake to make water cut across easily by decreasing the sludge EPS; on the other hand, charge neutralization occurred when the AlCl3-modified biochar (loaded with positively charged aluminum species on its surface) was dosed into the sludge system, thus destroying the stable sludge colloidal system, thus far easier to congregate the sludge particles, which enhanced the dewatering of the sludge.
郭俊元, 文小英, 羊润锦, 林越, 赖雨隆, 周育玉, 杨红. 玉米秸秆生物炭改善污泥脱水性能[J]. 中国环境科学, 2019, 39(8): 3316-3322.
GUO Jun-yuan, WEN Xiao-ying, YANG Run-jin, LIN Yue, LAI Yu-long, ZHOU Yu-yu, YANG Hong. Preparation of corn stalks biochar and improvement of dewatering performance of sludge. CHINA ENVIRONMENTAL SCIENCECE, 2019, 39(8): 3316-3322.
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