Sludge deep drying method and system based on air medium circulation

Abstract

The invention discloses a sludge deep drying method and system based on air medium circulation. The system comprises a sludge conditioning and dewatering device, a sludge pulverization and drying device, and a dryer. The method comprises the following steps: 1) adding a proper amount of an alkali-skeleton structure composite conditioner into the excess sludge with the water content of 90-95%, andstirring the excess sludge for 5-15 minutes to condition the excess sludge; dewatering the conditioned excess sludge to form a semi-dry mud cake with the water content of 45-60%; pulverizing and crushing the semi-dry mud cake into sludge powder particles with the particle size of 10-200 [mu]m, feeding dry air to dry the sludge powder particles to obtain dry sludge powder and generate moist air atthe same time; and then drying the moist air, recycling the moist air, and recycling the ineffective drying agent as the alkali-skeleton structure composite conditioner again. The method has the advantages of deep drying of sludge, low waste gas generation amount, high utilization rate of a drying agent and the like.

Description

technical field [0001] The invention relates to a method and system for deep drying of sludge based on air medium circulation, in particular to a method and process system for deep dehydration of excess sludge, which belongs to the subfield of treatment of excess sludge 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 environmental protecti...

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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