Device and method for enhancing sludge dewatering by means of periodic reversal electrocoagulation

Abstract

The invention relates to a device and a method for enhancing sludge dewatering by means of periodic reversal electrocoagulation, belonging to the field of sewage treatment. A main body of the device for enhancing sludge dewatering by means of periodic reversal electrocoagulation is a barrel used for containing sludge to be dewatered; the barrel is internally provided with a piston shifting along the longitudinal axis of the barrel, and a plate body which is used for bearing the sludge to be dewatered and is provided with a through hole; a flat plate iron electrode is fixed on the lower surfaceof the piston; at least one layer of filter cloth and a wire mesh electrode are sequentially fixed above the plate body; the sludge to be dewatered is placed between the flat plate iron electrode andthe wire mesh electrode; the flat plate iron electrode and the wire mesh electrode are separately connected with a periodic reversal power supply. According to the device and the method, the periodicreversal power supply is applied to a sludge dewatering process, so that the problem that anode surface passivation, which possibly occurs in an electrodialysis process of a direct current (DC) powersource in the past, affects the conductive effect can be effectively avoided.

Description

technical field [0001] The invention relates to a device and method for periodically reversing electrocoagulation enhanced sludge dehydration, belonging to the field of sewage treatment. Background technique [0002] Municipal sewage sludge is a kind of solid-liquid mixed substance, which is a kind of solid-liquid mixed substance, which is a kind of solid-liquid mixed substance, which contains a large number of microorganisms, pathogens, heavy metals and organic pollutants. In recent years, with the acceleration of urbanization, the rapid development of industrial production, the increase of urban population, the discharge of urban industrial wastewater and domestic sewage is increasing, and the rate of urban sewage treatment is also increasing year by year. With the joint increase of sewage discharge and sewage treatment rate, my country's sludge production has increased rapidly year by year, and such a large amount of sludge has caused great pressure on the environment. ...

AI Technical Summary

Problems solved by technology

The mechanical dehydration method has a certain effect on the pore water in the sludge, but it is difficult to remove the capillary and adsorbed water (Glendinning, 2007). In addition, the sludge contains a large number of microbial cells and organic colloidal substances, and the particle size is mostly less than 10 -4 m, so the sludge has high viscosity, small pores, low hydraulic permeability coefficient, and difficult mechanical dewatering (Brendan, 2006)

At present, the mechanical dehydration method used by domestic sewage treatment plants can only reduce the water content to about 80% (Zhan Dadong, 2009), which means that every 100 tons of sludge discharged from sewage treatment plants contains 80 tons of water, a large amount The moisture in the sludge brings many difficulties to the subsequent disposal of the sludge

In 2007, the Ministry of Construction issued the "Urban Sewage Treatment Plant Sludge Disposal--Mixed Landfill Mud (CJ / T249-2007)" standard and in 2008 the Ministry of Environmental Protection issued the "Life Waste Landfill Pollution Control Standard (GB16889-2008 )” clearly stipulates that the water content of sludge mixed landfill should be less than 60%. At present, sludge with a water content of 80% produced by mechanical dehydration treatment is difficult to meet the requirements of sludge landfill.

[0012] However, when metallic iron is used as a soluble metal anode to treat sludge by electrodynamic dehydration technology, the process is similar to the electrocoagulation process of sewage treatment. The phenomenon that the reaction rate decreases, which affects the treatment effect and increases energy consumption

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