Abstract：To realize deep-dewatering of municipal sewage sludge, the combined alternating electric field (AEF) electroosmosis technology was developed with iron modified biomass as the skeleton for disposal of sludge. Based on a single-factor experiment, the effect of the combined technology on sludge dewatering behavior was studied. Moreover, technical parameters of sludge dewatering were optimized with the response surface method (RSM). After mixing the sludge with corn stalks modified by FeCl3 of 0.03g/mL, in the AEF of unequal duty cycle at 4.33:1, voltage at 17.22V/cm, modified biomass dosage at 96.81mg/g DS, modified biomass moisture at 61.91%, biomass particle size at 1.05mm, and anode-cathode distance at 2.10cm, the dewatered sludge with a moisture content of 58.21% could be obtained, and the dewatering energy consumption was 0.0148kW·h/kg RW (Removed water). According to scanning electron microscope (SEM) characterization of the dewatered sludge, iron modified biomass well supports the sludge as the skeleton, which was conducive to the mechanical strength and permeability of the sludge. According to thermogravimetric analysis (TGA), the upper and lower combustion process in the dewatered sludge could be divided into the stage of precipitation of free water and bond water, the stage of precipitation and combustion of volatile, and the stage of decomposition of inorganic salts. The dewatered sludge mixed with iron modified biomass showed higher organic content and faster combustion.
李亚林, 陈高昂, 孙丽莉, 王恩赐, 宋雨晴, 孙趁心. 交变电场-铁改性生物质强化城市污泥深度脱水[J]. 中国环境科学, 2022, 42(7): 3140-3148.
LI Ya-lin, CHEN Gao-ang, SUN Li-li, WANG En-ci, SONG Yu-qing, SUN Chen-xin. Alternating electric field combined with iron-modified biomass to enhance the deep-dewatering of municipal sludge. CHINA ENVIRONMENTAL SCIENCECE, 2022, 42(7): 3140-3148.
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