Method for reducing coal consumption of coal fired power plant by arranging steam pipe type drying system

Abstract

The invention provides a method for reducing coal consumption of a coal fired power plant by arranging a steam pipe type drying system. The steam pipe type drying system is arranged between a coal dust bin and a weighing belt of the conventional coal fired boiler generating unit and a coal mill, partial working superheated steam is extracted from a steam turbine and used as a drying medium, the moisture in the coal dust is evaporated by using sensible heat and latent heat of the superheated steam, and the condensed water is delivered to an oxygen remover of the steam turbine unit through a condensed water pump and recycled after the superheated steam is condensed into water. The method has the characteristics of saving coal, reducing consumption, recycling waste heat, reducing the discharge of carbon dioxide and adapting to the national industrial policies of energy conservation and emission reduction.

Description

technical field [0001] The invention relates to the technical field of saving coal and reducing consumption in coal-fired steam generator sets in power plants, and proposes a method for reducing coal consumption in coal-fired power plants by adding steam tube drying. Background technique [0002] Coal-fired steam generators are all condensing steam generators based on the Rankine cycle, and the steam power cycle system of coal-fired boiler generators. The working process is: the raw coal is dried by a coal mill, ground into coal powder, and then enters the boiler for combustion. The heat is released, and the water absorbs heat and vaporizes into saturated steam in the boiler drum at constant pressure. Saturated steam absorbs heat in the superheater to become superheated steam. The superheated steam expands through the steam turbine to do work, and has a certain heat loss. At the outlet of the steam turbine, the exhausted steam after the steam turbine expands and works enters...

AI Technical Summary

Problems solved by technology

[0004] ① When the pulverized coal enters the pulverizing system (coal mill, coal pulverizing fan, etc.) and the boiler contains moisture, it evaporates in the pulverizing system and the boiler furnace, and the required heat is provided by the combustion heat of the pulverized coal itself in the boiler, so , evaporating the water in the pulverized coal needs to consume pulverized coal, which consumes a lot

[0005] ②The superheated steam generates electricity through the steam turbine, and the conversion rate of the thermal energy of the superheated steam into electric work is less than 50%. The reason for the low power generation efficiency is that the steam turbine uses about 1 / 3 of the latent heat of evaporation of the steam by extracting steam to heat the condensate, 2 / 3 The latent heat of evaporation of steam cannot be used, it can only be taken away by the condensing medium through the condenser, and lost through the cooling tower or air-cooled island, which becomes the largest heat consumption that cannot be used, that is, the loss of cold source of the condensing steam generator set

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