Energy self-feed type fluidized bed sludge incineration and tail gas pollution control system

Abstract

The invention relates to an energy self-feed type fluidized bed sludge incineration and tail gas pollution control system. The system comprises a fluidized bed incinerator, a waste heat boiler, a sludge dryer, a separator, a spray dehydrating tower, a sewage treatment pool, an air preheater, an acid air absorption tower, a bag-type dust collector, an air blower and an induced draft fan. Wet sludge is dried in the dryer (a heat source is steam produced through combustion of dried sludge), and the dried sludge (granular) is conveyed into a fluidized bed and combusted; as the calorific value of the dried sludge is high, the normal combustion can be kept, and the heat produced through combustion is used for drying the wet sludge, so that an energy conversion process is finished. Waste air which contains water vapor and comes from the dryer is sprayed and dehydrated by a spray condensation tower and then is conveyed into a fluidized bed and is combusted. The self feed of sludge incineration energy can be realized, the waste water and waste air produced at each treatment section can be subjected to deodorization and innocent treatment, and the system has the advantages of high energy utilization rate, good treatment effect, and the like, and a small amount of pollutant is discharged.

Description

technical field [0001] The invention relates to environmental protection equipment, in particular to an energy self-sufficient fluidized bed sludge incineration and tail gas pollution control system. Background technique [0002] The annual dry sludge produced by urban sewage treatment plants in my country is about 25×10 4 t, based on wet sludge, is about 450~550×10 4 t, and grow at a rate of about 15% per year. Sludge contains a large amount of organic matter and rich nitrogen, phosphorus and other nutrients. Arbitrary discharge into the water body will consume a large amount of oxygen in the water body, resulting in deterioration of water quality and seriously affecting the survival of aquatic organisms; the nutrients in the sludge are also It will cause eutrophication of the water body and a large number of algae, thereby deteriorating the water quality and reducing the fishery output; in addition, there are many toxic substances, heavy metals, pathogenic bacteria, para...

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Problems solved by technology

[0005] Invention patent CN200410086312.5 "a wet sludge incineration treatment method and incineration treatment device", invention patent CN200510038416.3 "sludge incineration treatment method and sludge incineration treatment process", discloses that wet sludge with a water content of 70-80% The mud is directly sent to the incinerator for combustion, which has a great impact on the stable combustion in the furnace, and requires the burning of a large amount of auxiliary fuel, which is uneconomical from the perspective of energy conservation.

[0006] Invention patent CN200610037604.9 "Urban sludge fluidized bed incineration device and method" and invention patent CN200710060213.3 "Wet sludge circulating fluidized bed harmless incineration integrated treatment process", discloses a sludge incineration process, However, for the sewage problem and acid gas (HCl, SO 2 ), heavy metals and dioxin control measures are not mentioned

[0007] The utility model patent CN20082012330.x discloses a wet sludge drying and incineration treatment device, which sends the dried waste gas (containing a large amount of water vapor) directly into the furnace for combustion, so that on the one hand, the combustion temperature in the furnace is reduced, and the amount of auxiliary fuel is increased. On the other hand, a large amount of water vapor is discharged from the tail gas, which takes away a large amount of heat, increases the heat loss of the system, and greatly reduces the thermal efficiency of the incinerator

[0008] Invention patent CN200810238869.4 discloses "a wet sludge incineration treatment method with condensation drying". In this invention, a partition wall heat exchanger is installed after the dust collector, and the wet sludge with a moisture content of 80% is heated by low-temperature flue gas , due to the low temperature of the flue gas, the heating effect on the wet sludge is very limited, and the heat transfer of the partition wall is not uniform, so it is difficult to achieve the expected effect

In addition, acid gases (HCl, SO 2 ), heavy metals and dioxin control measures are not mentioned

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