Method of blending combustion of fuel coal fly ash in biomass circulating fluidized bed boiler and a device thereof

Abstract

The invention discloses a method of blending combustion of fuel coal fly ash in a biomass circulating fluidized bed boiler and a device thereof. In the method, the fuel coal fly ash is jetted onto the bottom of a dense phase combustion zone bed layer inside the biomass circulating fluidized bed boiler so that the fuel coal fly ash is mixed with very hot biomass bed materials in a bubble state or a turbulent fluidized state to generate intensive heat and mass transfer and temperature increase with violent rolling and friction, thereby grinding-off ash shells on the external layer of the fuel coal fly ash to expose unburnt residual carbon black core therein, and finally the fuel coal fly ash is completely combusted in the dense phase combustion zone and a dilute phase combustion zone. The device is mainly composed of following units which are matched with the biomass circulating fluidized bed boiler: a fuel coal fly ash storage bin, a rotary material feeding device, an ejector, an air blower, a transporting pipeline and a bottom feeding abrasion resistant spray nozzle. By means of the method and the device, the fuel coal fly ash can be recycled to the biomass circulating fluidized bed boiler for fully combustion again to perform secondary power generation, thereby reducing the use amount of a biomass fuel, increasing the power generation capacity of unit fuel and meanwhile can reduce emission of coal combustion pollutant.

Description

technical field [0001] The invention relates to a technology for recycling waste ash produced in the process of boiler combustion and generating electricity, and for energy saving and emission reduction, and specifically refers to a method and equipment for blending combustion of coal-fired fly ash in a biomass circulating fluidized bed boiler. Background technique [0002] With the increasing demand for energy in modern society, the construction of coal-fired boiler power plants is also increasing. Although my country has a vast territory and a wide distribution of coal resources, there are many types of coal, especially in the south and southwest of China. Many provinces have a large amount of low-volatile coal such as anthracite and lean coal. When coal-fired boiler power plants burn these low-grade coals, there are common problems such as high carbon content in coal-fired fly ash and unsatisfactory burnout degree, which not only wastes a lot of coal resources, but also b...

AI Technical Summary

Problems solved by technology

However, restricted by the radius and total amount of biomass fuel resource acquisition, there are already many biomass boiler power plants that have reduced the designed production load because they cannot purchase biomass fuel, especially when the power plant adopts a variety of biomass fuels. For biomass circulating fluidized bed boilers with high efficiency and full combustion, low residual ash content, and good environmental performance, the demand for biomass fuel to maintain continuous power generation is extremely large, and even production can only be stopped if the purchase volume cannot be guaranteed

How to effectively expand the source of raw materials for biomass boiler power plants and ensure their production scale and power generation efficiency has always been a recognized problem and direction of exploration by those skilled in the art, but so far no satisfactory technical solutions have come out

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