Bottom feed type gas method and equipment for preparing gas with no tar products through oxygendeficient fluid bed combustion

Abstract

This invention relates to downdraft gasification method and equipment for preparing tar-free product gas by oxygen-deficient fluidized burning. The equipment comprised a front fluidized bed burner, a downdraft fixed bed gasifier set lower than the burner, a transporting pipe for carbocoal and semi-finished gas connecting the burner and the gasifying furnace, a fuel inlet and an oxidant inlet. The method comprised: (1) adding fuel through the fuel inlet of the fluidized bed burner, and performing oxygen-deficient fluidized burning with oxidant added through the oxidant inlet at the bottom of the fluidized bed burner to obtain carbocoal and semi-finished gas containing tar, and (2) sending the unseparated carbooal and semi-finished gas containing tar to a down-draft fixed bed gasifier at a high temperature to gasify the carbocoal, and modifying and cracking the tar introduced by the semi-finished gas by the catalytic activity of high-temperature carbocoal to obtain the product gas with tar. The equipment has such advantages as simple structure, easy operation and high gasifying efficiency, and is suitable for a wide variety of fuels and can produce product gas without tar.

Description

technical field

[0001] The invention belongs to the technical field of clean energy, and particularly relates to a pre-oxygen-poor fluidized combustion downdraft gasification method and device for preparing tar-free product gas. The fuel includes coal, biomass, urban waste, and high-water solid waste substances (such as sludge), a mixture of one or more of these solid fuels and other gaseous and liquid fuels or waste. Background technique

[0002] The research and development of coal gasification technology has a history of nearly a hundred years, and the gasification technology of biomass and organic solid waste has also developed rapidly since the 1980s. However, the gas conversion efficiency achieved by various existing gasification technologies is seldom higher than 70% (efficiency is defined as the percentage of the calorific value of gas products to the sum of the calorific value of the fuel used and the energy consumed in the gasification process), However, the tar c...

Examples

Embodiment Construction

[0073] attached figure 2 For the implementation of figure 1 A schematic structural diagram of a gasification device for the gasification method of the present invention is shown. The device comprises: a downdraft fixed-bed gasifier 1, a fluidized-bed burner 3 and a delivery channel 5 connecting the two reactors. Here, the burner 3 referred to constitutes the pre-gasification stage, and the downdraft gasifier 1 constitutes the post-gasification stage. The transfer channel 5 is provided outside the fluidized bed combustor 3 . Fuel is fed into the fluidized bed reactor from the other side with respect to the channel 5 (to prevent the fed fuel from reaching the delivery channel 5 too quickly via a possible short circuit). According to the principle of the invention, the proportion of oxidant (detailed in the summary of the invention) is supplied into the fluidized bed gas dispersion chamber 10, and after being distributed by the gas dispersion plate 9, the fuel particles in th...

technical field

[0001] The invention belongs to the technical field of clean energy, and particularly relates to a pre-oxygen-poor fluidized combustion downdraft gasification method and device for preparing tar-free product gas. The fuel includes coal, biomass, urban waste, and high-water solid waste substances (such as sludge), a mixture of one or more of these solid fuels and other gaseous and liquid fuels or waste. Background technique

[0002] The research and development of coal gasification technology has a history of nearly a hundred years, and the gasification technology of biomass and organic solid waste has also developed rapidly since the 1980s. However, the gas conversion efficiency achieved by various existing gasification technologies is seldom higher than 70% (efficiency is defined as the percentage of the calorific value of gas products to the sum of the calorific value of the fuel used and the energy consumed in the gasification process), However, the tar c...

Examples

Embodiment Construction

[0073] attached figure 2 For the implementation of figure 1 A schematic structural diagram of a gasification device for the gasification method of the present invention is shown. The device comprises: a downdraft fixed-bed gasifier 1, a fluidized-bed burner 3 and a delivery channel 5 connecting the two reactors. Here, the burner 3 referred to constitutes the pre-gasification stage, and the downdraft gasifier 1 constitutes the post-gasification stage. The transfer channel 5 is provided outside the fluidized bed combustor 3 . Fuel is fed into the fluidized bed reactor from the other side with respect to the channel 5 (to prevent the fed fuel from reaching the delivery channel 5 too quickly via a possible short circuit). According to the principle of the invention, the proportion of oxidant (detailed in the summary of the invention) is supplied into the fluidized bed gas dispersion chamber 10, and after being distributed by the gas dispersion plate 9, the fuel particles in th...

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