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Coal gasification is one of the clean use of coal gasification process has been a bottleneck restricting the efficient coal gasification tar also cause pipe blockage, corrosion of the equipment, the energy loss and environmental pollution problems. Therefore, the gasification tar the entire gasification system even lower level with gas equipment is crucial. Factors from the furnace, the furnace structure and purification furnace three reviewed the various factors affecting the tar content. The analysis found that the furnace factors (temperature, residence time, pressure, atmosphere, and catalyst) and the furnace structure (two-stage air, under suction) through the influence of tar cracking, improve the conversion rate and reduces the tar content. Purification sucked tar furnace transferred from the gas phase and collected, not full recovery of the energy in the tar, may also cause secondary pollution. Therefore, strengthening the cracking of tar is to reduce the tar content of the gas in the reliable, effective way. Found in the analysis of the composition and nature of the gasification tar gasification tar phenols content, combustion performance, with the conditions of the preparation of carbon fiber, but due to the coal and process gas generally higher impurity content of tar, low quality, poor secondary processing performance, will tar deep processing bring some difficulties. In addition, the cost of inputs to some extent, restricted the large-scale development of the tar deep-processing industry concentrated in the extraction, transportation and storage links. The purpose of the current situation, the the gasification tar route still to go deep processing of large-scale processing needed to proceed from the formation of links. Cracking experiment, the tar conversion rate with the increase of the temperature and residence time significantly increased, reached a 91.73% conversion of 1200 ℃, 12s. After lysis, the gas composition change, a significant increase in heat value. This description The cracking reaction not only to reduce the tar content in the gas, but also change the composition of the gas to improve gas quality. Catalytic cracking experiment, the tar only be achieved at 900 ℃ the conversion rate of 94.75%, and to achieve a desired temperature by the same conversion rate fell from about 30%. Meanwhile, the experiments also reflects the catalyst easily coke, inactivation and result in the decline of life and the catalytic effect. In this paper, no coal tar gasification idea that by strengthening the tar cracking reaction, to reduce the tar content in baked Gas purpose, reducing the burden of the gas purification links, while avoiding the problems of gasification tar deep processing. Higher economic practicality furnace pyrolysis cracking form of comparison, the basic idea, design tar gasifier. The next suction furnace on the basis of structural adjustment. Throat by adding secondary air, set to raise the furnace temperature, and the design of conical reducing zone the venturi ejector pipe to extend the tar to provide the appropriate conditions for the residence time in the high temperature zone for the cracking of the tar.
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