Latent heat recoverable multi-phase change sludge drying method and device

Abstract

The invention discloses a latent heat recoverable multi-phase change sludge drying method and a latent heat recoverable multi-phase change sludge drying device, which are designed for solving the technical problems that the energy consumption is high, the latent heat of the sludge vapor cannot be recovered and reused, the dried tail gas pollutes the environment, the operating cost is high and thelike in the conventional sludge drying technology. Due to the combination of a low-temperature vapor turntable dryer, a sludge waste vapor latent heat recover heat pump and a tail gas purification device, and the use of indirect phase change heat exchange for low-temperature vapor, the heat exchange is improved, and the loss of organic components of the sludge is low. The latent heat of the sludge drying tail gas is recovered by using the latent heat recover heat pump, and the recovered heat energy is reused for sludge drying. Therefore, the heat efficiency is improved, the operating cost is reduced, and the problems that the heat utilization ratio is low, the operating cost is high and the like in the sludge drying process are better solved. The dried products meet the requirement of baking light and energy-saving bricks and producing cement laminated products, and over 90 percent of heat value of the original sludge is maintained. Therefore, the resource utilization value of the sludge is maximized.

Description

technical field [0001] The present invention relates to a sludge drying method and equipment, in particular to a latent heat recovery type multi-phase change sludge drying method and equipment, especially suitable for harmless and reduction of residual sludge in urban sewage treatment plants processing. Background technique [0002] At present, more than 90% of urban sewage treatment plants use the activated sludge method, accompanied by a large amount of excess sludge. According to statistics, the amount of sludge produced by domestic sewage treatment in my country alone reaches hundreds of millions of tons every year; in addition, industrial processes such as chemical, papermaking and pharmaceuticals, and dredging of rivers and lakes also produce a large amount of sludge. Usually the remaining sludge has the characteristics of high water content (97%), perishable and smelly, and contains toxic and harmful substances such as pathogenic bacteria, parasite eggs, heavy metals...

AI Technical Summary

Problems solved by technology

However, the waste steam and tail gas after drying are directly discharged into the atmosphere, causing pollution and waste of valuable energy, and the treatment functions such as sludge drying waste steam recovery and tail gas treatment cannot be realized.

Moreover, the waste steam generated in the sludge drying process in the existing sludge drying technology is usually condensed by a direct condenser and then discharged, and the energy is not recovered and reused, which increases the energy consumption of drying.

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