Harmless recycling treatment process for urban sludge

Abstract

A harmless recycling treatment process for urban sludge carries out urban sludge treatment through the prior pulverized coal boiler and coal conveying and tail exhaust treatment systems in a power plant. In the treatment process, flue gas extracted from the front part of an air preheater of a power plant pulverized coal boiler is mixed with flue gas extracted from the back part of a power plant boiler dust remover into flue gas with the temperature ranging between 140 and 180 DEG C; the flue gas is conveyed to a sludge drier to carry out sludge drying; and the dried sludge is fed into a power plant coal conveying system, mixed with coal, and then fed into a furnace to carry out incineration for power generation so as to realize the recycling utilization of the sludge. The coal and dry sludge are burnt in a boiler and discharged flue gas is fed into the power plant boiler dust remover and a wet desulphurization system for treatment; and the flue gas after the drying and tail gas generated by storing and conveying the dry sludge are discharged into a power plant desulphurization system for treatment, so that the standard discharge of pollutants is realized and secondary environmental pollution is eliminated. The harmless recycling treatment process makes effective use of the prior power plant boiler and coal conveying, burning, dust removal and desulphurization facilities, and has the advantages of simple equipment, less investment, short construction cycle and low operating cost.

Description

technical field [0001] The invention relates to an urban sludge disposal process, which belongs to the technical field of environmental protection and treatment, and in particular to a process for harmless and resourceful disposal of urban sludge by utilizing the existing pulverized coal boiler, coal conveying system, and tail gas emission treatment system of a power plant craft. Background technique [0002] At present, domestic municipal sludge treatment mainly adopts three methods: landfill, biocomposting, and dry incineration to treat sludge, but these three methods have disadvantages: landfilling sludge needs to occupy a large amount of agricultural land; investment in biocomposting equipment Larger, and the annual operating cost is high; and the drying and incineration of sludge, there are not only the method of adopting new incineration facilities, but also the method of using the waste heat of boiler flue gas to dry the sludge, but there are generally large project i...

AI Technical Summary

Problems solved by technology

[0002] At present, domestic municipal sludge treatment mainly adopts three methods: landfill, biocomposting, and dry incineration to treat sludge, but these three methods have disadvantages: landfilling sludge needs to occupy a large amount of agricultural land; investment in biocomposting equipment Larger, and the annual operating cost is high; and the drying and incineration of sludge, there are not only the method of adopting new incineration facilities, but also the method of using the waste heat of boiler flue gas to dry the sludge, but there are generally large project investment and high operating costs. question

But its disadvantages are: 1. Pretreatment is required before the sludge is dried, which occupies a large area and the process is complicated; 2. The drying process of the sludge adopts segmental drying, and the system is complicated; 3. It is necessary to build a new tail gas treatment facility to treat the tail gas from sludge drying, and the investment and maintenance costs are high

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