Sludge deep drying method and system based on low-temperature heat source circulation

Abstract

The invention discloses a sludge deep drying method and system based on low-temperature heat source circulation. The method comprises the following steps: 1) adding excess sludge to be treated into asludge pulverization and drying device, and pulverizing and crushing the sludge to be treated into sludge powder particles with the particle size of 50-300 [mu]m; 2) then feeding dry air, mixing the dry air with the sludge powder particles under a stirring condition, drying the sludge powder particles to obtain dry sludge powder, wherein the dry air becomes low-temperature humid air carrying the dry sludge powder; 3) carrying out gas-powder separation on the low-temperature humid air carrying the sludge dry powder through a gas-powder separation device, wherein the separated solid substance isthe sludge dry powder; 4) feeding the separated low-temperature moisture-containing air into a condensation dehumidifier for condensing water removal to form low-temperature and low-temperature air;5) feeding low-low-temperature air into a heat exchanger to be heated for forming dry air again to be repeatedly used, wherein heat absorbed by cooling water is subjected to heat exchange with a low-temperature heat source and the low-low-temperature air is heated after the temperature of the low-low-temperature air is raised, so that the method has the advantages of sludge deep drying, low wastegas generation amount and the like.

Description

technical field [0001] The invention relates to a method and system for deep drying of sludge based on low-temperature heat source circulation, in particular to a method and process system for deep dehydration of excess sludge, which belongs to the subfield of excess sludge treatment in sewage treatment plants in the field of environmental protection technology. Background technique [0002] With the development of our country's society and urbanization, the amount of urban sewage is increasing, the number of corresponding sewage treatment facilities is also increasing, and the by-product of sewage treatment - the amount of residual sludge is also increasing. . As of 2017, the annual output of surplus sludge in my country has exceeded 40 million tons, while the harmless treatment rate is less than 10%. How to properly handle and dispose of these continuously generated and increasingly large amounts of sludge has become an urgent problem to be solved in my country's environm...

AI Technical Summary

Problems solved by technology

As of 2017, the annual output of surplus sludge in my country has exceeded 40 million tons, while the harmless treatment rate is less than 10%.

The above process can quickly remove the water in the sludge, but the degree of dehydration is limited, and it is difficult to achieve deep drying of the sludge (moisture content ≤ 20%)

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