Integrated system and method for generating electricity employing drying and burning of sludge

Abstract

The invention provides an integrated system and method for generating electricity employing drying and burning of sludge. A gas turbine is connected with a generator; a smoke outlet of the gas turbine is communicated with a sludge drying device; an outlet of the sludge drying device is connected with a gas-solid separating device; a dry sludge outlet of the gas-solid separating device is communicated with a hopper; the hopper is communicated with a feed pipe of a fluidized bed boiler; the smoke outlet of the fluidized bed boiler is communicated with a separator; a solid outlet of the separator is communicated with a feeding hole of the fluidized bed boiler through a return feeder; smoke afterheat of the gas turbine is utilized as a heat source for drying the sludge; gradient utilization of an energy source and high thermal efficiency are achieved; the problem of emission of sulfur dioxide, nitric oxide, dust and the like generated by burning fire coal to dry the sludge is avoided; the problem of polluting underground water and the environment caused by sludge landfill and soil utilization is effectively avoided; the moisture content of the dried sludge is greatly reduced; stable combustion can be achieved inside the fluidized bed boiler; auxiliary fuel does not need to be added; a highly toxic pollutant dioxin is avoided.

Description

technical field [0001] The invention relates to the field of sewage sludge treatment, in particular to an integrated system and method for sludge drying, incineration and power generation. Background technique [0002] (1) Output of sewage sludge and its hazards [0003] With the rapid advancement of urbanization, China's sewage treatment industry has developed rapidly, the sewage treatment capacity and treatment rate have increased rapidly, and the output of sewage sludge has increased rapidly. By the end of 2009, 1,992 urban sewage treatment plants had been put into operation in China, treating 28 billion cubic meters of sewage 3 , producing about 20.05 million tons of sludge with a moisture content of 80%. With the increase of the level of urbanization and the amount of sewage treatment, the amount of sludge will soon exceed 30 million tons. The composition and chemical properties of sludge are complex, including organic matter, plant nutrients, etc., as well as harmfu...

AI Technical Summary

Problems solved by technology

However, the drying process of sludge incineration treatment needs to consume high-quality energy such as coal, and the cost is high; in addition, the wet sludge drying process needs to consume coal to provide energy, and coal combustion emits sulfur dioxide, nitrogen oxides, dust and other atmospheric gases Pollutants

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