A process for cogeneration of electricity, charcoal and heat by fluidized bed gasification of straw

Abstract

The invention relates to a process for cogenerating electricity, charcoal and heat through fluidized-bed gasified power generation of straws. The process is characterized in that hot combustible gas is prepared from the straws through a biomass fluidized-bed gasification furnace and serves as fuel of a boiler, and a steam turbine is propelled by steam generated by the boiler so as to generate electricity and obtain three kinds of products, i.e., electricity, charcoal and heat simultaneously. The process comprises the steps: cutting the biomass raw material into biomass cuts with the length of 20-30mm, and then, drying the biomass cuts until the moisture content of the biomass cuts is 20% if the moisture content is higher than 20%; then, feeding the biomass cuts to a multi-cogeneration fluidized-bed gasification furnace for gasifying; supplying the hot combustible gas, obtained after gasifying, to a gas-fired boiler through a combustor; cooling and collecting straw charcoal through a collection system, adding a variety of chemical fertilizers into the straw charcoal, and then, carrying out granulating, shaping and drying, so as to prepare a charcoal-based compounded fertilizer; and enabling the steam of the boiler to propel the steam turbine for electricity generation and heat supplying and auxiliary systems of the steam turbine. The process has the advantages that biomass of the straws and the like is adopted as a raw material, so that the resource-converting utilization of the straw biomass and environmental protection are facilitated; and the process is stable in operation, high in hot-combustible-gas combustion heat efficiency, diverse in product and good in economic benefit and is applicable to large-scale application.

Description

technical field [0001] The invention relates to a process for generating electricity, charcoal and heat through fluidized bed gasification of straws, which belongs to the field of biomass energy and fertilizers. Background technique [0002] Under the dual pressure of energy and the environment, vigorously developing clean and renewable energy has become a very urgent worldwide issue before governments all over the world. Compared with other new energy sources, biomass energy has the characteristics of being renewable, less polluting, transportable and storing, and most compatible with the current energy industry, so it has attracted special attention. China is a large agricultural country, with abundant agricultural and forestry biomass resources, especially straw resources, huge quantity and diverse varieties. Under the background of favorable policies, the utilization of biomass resources has achieved considerable development in China, but at the same time, many problems...

AI Technical Summary

Problems solved by technology

During the operation of this kind of system, the combustible gas produced by the gasifier contains a large amount of dust and tar. When used for internal combustion engine power generation, the combustible gas must be deeply purified. At present, the better combustible gas purification method is water washing and electric coke capture. Coke capture has requirements on the oxygen content in the gas. If it exceeds the standard, safety accidents may occur, which makes the electric coke capture method unable to be popularized.

The combustible gas has been washed and purified, and almost all the dust and combustible gas have been removed, but a small amount of tar remains. This small amount of tar seriously affects the operation of the internal combustion generator, resulting in a decrease in the stability and efficiency of the internal combustion generator and an increase in maintenance costs. , especially large-scale grid-connected power generation cannot run stably and is difficult to popularize and apply; this kind of process has a single product and poor economic benefits

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