Method for realizing anti-shrinkage recarburization sludge drying

Abstract

A method for realizing anti-shrinkage recarburization sludge drying is characterized in that an organic pore-forming agent and a catalyst are added into a sludge dry basis subjected to centrifugal dewatering to be uniformly mixed, distributing is carried out in a solar power interlayer drying system, and through the organic combination of the synergistic effect of framework construction and the pore-forming agent and solar power drying, a low-shrinkage recarburization function on the basis of realizing quick sludge drying is realized, wherein the organic pore-forming agent comprises 50-80% of a pore-forming agent and 20-50% of an aggregate according to the mass ratio; the pore-forming agent is prepared by mixing one or more of natural fibers such as starch, saw dust, sawdust and crop stalks according to an arbitrary ratio; the aggregate is prepared by mixing one or more of high-molecular polymers such as polyvinyl chloride, polystyrene, polyvinyl alcohol and resin according to an arbitrary ratio; the catalyst is the KOH solution with the concentration of greater than or equal to 0.4 mol / L, and the mass ratio of the catalyst to the organic pore-forming agent is 1:1, and the adding amount of the organic pore-forming agent is 5-30% of that of the sludge dry basis. According to the method, the dried sludge size is reduced, and when the sludge moisture content is less than 20%, the dried sludge size is reduced to 16.4-52.2% of the original size of sludge; after pyrolysis, the carbon recovery rate is increased by 20-30%, and BET is increased by 40-120%.

Description

technical field [0001] The invention relates to a solid waste treatment method, in particular to a method for reducing drying shrinkage and increasing sludge carbon content under the assistance of solar energy for sludge drying, which belongs to the technical field of environmental protection. Background technique [0002] With the continuous improvement of my country's urban sewage treatment rate, the sludge output of urban sewage treatment plants has also increased sharply. As of the end of June 2013, 3,479 urban sewage treatment plants have been built nationwide, with a sewage treatment capacity of about 120 million cubic meters per day. The most direct result of the large-scale construction and operation of sewage treatment plants is a substantial increase in the amount of sludge. It is predicted that by 2015, the annual output of wet sludge (with a water content of 80%) in urban sewage treatment plants will reach 33.59 million tons, that is, 92,000 tons of sludge per d...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problem of dense dry sludge formed due to water escape in the existing sludge drying method, which is not conducive to subsequent heat treatment, and the organic carbon content in the sludge is low, which is not conducive to the subsequent burning of activated carbon, etc. In order to solve the problem of sludge drying, we use organic pore-forming agent, carbon material skeleton and other external chemical methods, combined with direct drying of solar energy, to provide a sludge drying anti-shrinkage and carbon increase method that can improve the properties of sludge after drying, so as to achieve the goal of accelerating pollution. The drying rate of mud heat can also improve the quality of carbon production from sludge after drying, thereby greatly improving social and economic benefits

Images