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| Experimental study on the improvement of dredged slurry by flocculation-step-by-step loading voltage electro-osmosis method |
| YUAN Guohui1，2，HU Xiuqing1，2，LIU Feiyu3，TAO Yu3，FU Hongtao4，WANG Jun1，2 |
| (1. School of Civil Engineering and Architecture，Wenzhou University，Wenzhou，Zhejiang 325035，China；2. Key Laboratory of Engineering and Technology for Soft Soil Foundation and Tideland Reclamation of Zhejiang Province，Wenzhou University，Wenzhou，Zhejiang 325035，China；3. Department of Civil Engineering，Shanghai University，Shanghai 200444，China；
4. Department of Civil Engineering and Architecture，Saga University，Saga 840–8502，Japan) |
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Abstract Aiming at the problem of high energy consumption during electro-osmosis process and the uneven consolidation effect of dredged slurry by electro-osmosis method，the inorganic flocculant CaCl2 was used to optimize the traditional electro-osmosis method，and the dredged slurry was treated by the energization method of step-by-step voltage loading during electro-osmosis process. Meanwhile，the effect of flocculation-step-by-step loading voltage electro-osmosis method in the treatment of dredged slurry under different loading voltage levels and inorganic flocculant CaCl2 mixing ratio was studied. The thirteen laboratory tests were performed on dredged slurry. The test results show that，compared with the traditional electro-osmosis method，the flocculation- step-by-step loading voltage electro-osmosis method effectively reduces the non-electroosmotic energy consumption in the treatment of dredged slurry. Most of the electrical energy is used for the electroosmotic drainage，thereby increasing the drainage of soil. Meanwhile，the flocculation-step-by-step loading voltage electro-osmosis method effectively restrains the attenuation of circuit current，and improves the electro-osmotic drainage efficiency in the treatment of dredged slurry. Moreover，compared with the traditional electro-osmosis method，the flocculation-step-by-step loading voltage method has less anodic corrosion and better integrity of soil. In addition，in the treatment of dredged slurry by flocculation-step-by-step loading voltage electro-osmosis method，when the mixing ratio of inorganic flocculant CaCl2 is 1%，the more the loading voltage level，the better the reinforcement effect of dredged slurry.
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2020, Vol. 39 
