Coal-sludge co-combustion system based on two-medium flue gas drying and circulating fluidized bed boiler

Abstract

The invention relates to a coal-sludge co-firing system based on two-medium flue gas drying and a circulating fluidized bed boiler. The outlet of the sludge storage bin is connected to the inlet of the spray drying pipe through a screw pump, and the inlet of the spray drying pipe It is connected to the outlet of the mixing chamber, and the inlet of the mixing chamber is divided into two paths, one path is connected to the outlet flue of the cyclone separator of the circulating fluidized bed boiler, the other path is connected to the outlet of the dust collector through the cold smoke fan, and the outlet of the spray drying pipe passes through the rotary feeder One is connected to the dry sludge bin, the outlet of the dry sludge bin is connected to the circulating fluidized bed boiler through a screw conveyor, the second outlet of the spray drying pipe is connected to the cyclone separator, and the discharge port of the cyclone separator is connected to the dry sludge through the second rotary feeder The silo, and the exhaust port of the cyclone separator are connected to the circulating fluidized bed boiler through the cooling condenser and the exhaust fan in turn. The invention can realize functions such as sludge drying, waste heat utilization of dry tail gas, co-firing of sludge and coal, and pollutant control, which is beneficial to prevent the diffusion of odor and dust, and has the characteristics of simple system, environmental protection and high efficiency.

Description

technical field [0001] The invention relates to a waste disposal system, in particular to a system for drying sludge and co-firing with coal. Background technique [0002] With the increasing amount of urban sewage generation and treatment, the sludge produced in the process of urban sewage treatment is also increasing day by day. Sludge is a floc composed of water, organic particles and inorganic particles, which contains a large amount of heavy metals, pathogens and refractory toxic organic substances, and emits odor. Therefore, sludge must be properly disposed of. [0003] Sludge pretreatment includes conditioning, concentration, dehydration, stabilization, and drying technologies. The final disposal of sludge mainly includes landfill, land use, construction material utilization, biological treatment, and incineration. Pyrolysis, gasification, and Emerging technologies such as thermal hydrolysis are also being researched and developed. Due to the increasing requirement...

AI Technical Summary

Problems solved by technology

This leads to complex system process, many equipments, large floor area and high investment cost; and because the dried sludge will emit dust and odor during the stacking and transportation process, and the sealing performance of the belt conveying system is poor, Therefore, it is easy to cause odor to spread in the factory area and nearby areas, resulting in a bad working environment and seriously affecting the enthusiasm of the power plant for incinerating sludge.

At present, there is also a sludge flue gas drying-pulverized coal boiler co-firing process scheme based on the fan mill pulverization system, but the gas-powder mixture produced during the process of drying the sludge in the fan mill and grinding it into powder has a strong The irritating smell, corrosiveness and high dust concentration make it difficult to separate the gas and powder, and the explosion-proof requirements are relatively high, so there is no engineering application yet.

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