Three-layer gas supply heating self-conversion tar gasifier

Abstract

The invention discloses a three-layer gas supply heating self-conversion tar gasifier. The gasifier is composed of a double bell coal feeder, a gasifier body, a three-layer of gas supply heating gasifier distributor, an ash residue discharging structure and a gas supply system; the three-layer of gas supply heating gasifier distributor is provided with a coal gas delivery line in the center in themiddle of the interlayer gasifier body, and the coal inlet at the bottom of the three-layer of gas supply heating gasifier distributor is arranged between a second gas supply heating gasifier distributor and a third gas supply heating gasifier distributor; a first gas supply heating gasifier distributor is located at the upper part of the gasifier body; the second gas supply heating gasifier distributor is located on the inner side of the middle gasifier wall and the outer side of the coal gas delivery line; and the third gas supply heating gasifier distributor is located in the center at thebottom of the gasifier body. Through the structural improvement of the gasifier, a high-temperature region can be formed, so that tar can be cracked and gasified in the high-temperature region, the performance of the gasifier can be greatly enhanced, efficient cleaning conversion of coal can be realized, and powerful support can be provided for development of coal gasification technologies.

Description

technical field [0001] The invention relates to a coal gasification furnace, in particular to a gas supply heating self-reforming tar gasification furnace comprising a furnace body, a distributor, a coal feeder, an ash discharge structure and a gas supply system. Background technique [0002] Coal gasification technology is the core and leading technology of the coal chemical industry, and one of the key technologies to realize the efficient and clean utilization of coal. It is also the development of coal-based chemical production, coal-based liquid fuel, synthetic natural gas, IGCC power generation, hydrogen production, and industrial gas. The foundation of process industries such as polygeneration systems; the rapid expansion of the coal chemical market has promoted the considerable progress of coal gasification technology. Pressurization, large-scale, and strong adaptability of raw materials are the development directions of advanced gasification technology. [0003] Gas...

AI Technical Summary

Problems solved by technology

[0005] There are three main problems in the practical application of the atmospheric fixed bed gasifier: one is that because air is used as the gasification agent, the N in the gas is 2 The proportion is relatively high, generally 50-60%, and the calorific value of gas is low, only 5.0-5.6MJ / m 3 Left and right, it belongs to low calorific value gas; the second is that the generated crude gas passes through the carbonization layer before leaving the gasifier, so that it contains a certain amount of tar and coal powder impurities, which causes inconvenience to the subsequent gas purification, processing, transportation and use; The third is that the atmospheric fixed bed technology uses lump coal as fuel, and the residence time in the furnace is long. Although the conversion rate of carbon is high, the reaction speed is slow, and the temperature and gasification intensity in the furnace are low. Therefore, single furnace production Poor ability

[0008] (1) Tar is carried by high-temperature gas and gradually condenses during transportation, adhering to the inner wall of the pipeline and the wall of related equipment, blocking the pipeline and corroding equipment, and posing a threat to the safe operation of the system;

[0009] (2) Tar is carried by the gasification gas and enters the downstream gas equipment, which will affect the safe operation of industrial furnace burners, internal combustion engines, gas turbines, compressors, etc. due to the entrainment of liquid droplets in the air flow;

[0010] (3) The tar produced by gasification accounts for about 3-10% of the total energy of gasification coal, which greatly reduces the gasification efficiency, and it is difficult to burn completely when tar is burned with combustible gas at low temperature. It is easy to produce carbon black, etc., which will seriously damage the gas utilization equipment and waste energy at the same time;

[0011] (4) Many substances in tar are carcinogenic. If these substances are discharged into the atmosphere, they will cause serious environmental pollution

[0012] It can be seen that the generation of tar in the gasification process not only wastes a part of energy, but also has considerable hazards. Therefore, the combustible gas with high tar content must be purified before use; the removal or reduction of combustible gas There are two main methods for medium tar: one is removal outside the furnace, and the other is removal inside the furnace. The removal methods outside the furnace mainly include thermal cracking, catalytic cracking, water washing, filtration, electric capture and Although the removal of tar outside the furnace can greatly reduce the tar content in the gas by mechanical trapping, etc., it has the disadvantages of energy waste, complex system, high cost, and easy to cause secondary pollution. It is not suitable for my country's many and scattered small and medium gasifier

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