System and method for drying sludge through waste heat of gas turbine

Abstract

The invention provides a system and a method for drying sludge through the waste heat of a gas turbine. The gas turbine is connected with a generator; a flue gas outlet of the gas turbine is communicated with a waste heat boiler; a steam outlet of the waste heat boiler is communicated with a steam turbine; the steam turbine is connected with the generator; a steam extraction pipe of the steam turbine is communicated with an inlet of a heated surface pipe of an internal thermal type fluidized bed dryer; an air outlet of an air heater is communicated with an air inlet of the internal thermal type fluidized bed dryer; wet sludge enters the internal thermal type fluidized bed dryer through a wet sludge pipe, flows outside the heated surface pipe, is dried and then is discharged into a dry sludge pipe from a discharging hole. Steam is produced through the flue gas waste heat of the gas turbine to push a steam turbine generator set to generate power, and the waste heat of the steam turbine is taken as a heat source for drying the sludge, so that gradient energy utilization is realized, the heat efficiency is high, and a peculiar smell is not discharged; the fluidization air of the fluidized bed dryer is preheated by hot water, so that the energy utilization rate is further improved, and the environmental problems of groundwater pollution and the like caused by sludge burying and soil utilization are effectively solved.

Description

technical field [0001] The invention relates to the fields of waste heat recovery and sludge drying, in particular to a system and method for drying sludge by utilizing the waste heat of a gas turbine. 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 w...

AI Technical Summary

Problems solved by technology

Although the gas-steam combined cycle combined with the extraction and condensing turbine can achieve an energy utilization rate of over 70%, but the exhaust gas temperature of the waste heat boiler matched with the gas turbine is generally as high as 120°C. Such low-temperature waste heat resources are difficult to use and can only be discharged. into the atmosphere, not only causing energy waste, but also causing environmental thermal pollution problems

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