| The base and the key of coal chemical industry is coal gasification. In the existing technology, Texaco coal-slurry gasification technology is the most mature and most widely used coal gasification process. Firstly, the process make coal ground into a certain size of pulverized coal, adding quantitative water and additive made from a certain concentration, viscosity, stability and fluidity of the slurry. Then, the coal slurry is pressurized sprayed into the reaction furnace, with the pure oxygen for combustion and partial oxidation, gasification to produce synthesis gas (CO+H2) in 1300℃～1400℃, in which high-quality of coal-water slurry is the foundation and the key of the process. Texaco coal water slurry gasification has the advantage of wide application, less energy consumption and waste. However, the shortcoming of the technique is that the quality of coal and pulping technology have a great influence for production efficiency. Practice has proved that when Texaco process uses the new raw coal, the coal water slurry properties must be studied to explore a variety of conditions on the coal slurry performance, determine the best pulping technology of raw coal process plan, and according to characteristics of the coal slurry gasifier operating parameters to optimize and adjust to achieve optimal operation of coal-water slurry gasification plant. Wansheng coal companly at its 600000tons/year acetic acid project firstly introduce the Texaco coal-slurry gasification technology in Chongqing. Before using the Chongqing coal source, the need for analysis of water, ash, volatile matter, carbon content and elemental composition in the coal, determine the optimum slurry process.Firstly, this paper has made some works about the Chongqing coal resource in respect of elemental and industrial analysis and IR analysis. The analysis results indicate that the Chongqing coal sample having low amount of water, volatile component and C/O, deep degree of anthracite metamorphism is one kind of coal species easily preparing coal slurry.Secondly, on the groundwork of Chongqing coal characteristics, the technological conditions in preparation of coal slurry with high concentration were probed. It was also investigated different additives, combination additives, temperature, pH to the effect on the preparation features of coal slurry. The results showed that the coal resource has a relatively good performance in preparation of coal slurry and three kinds of additives can make the coal slurry's maximum concentration reaching R%. By comparing the three kinds of additives, it's found that naphthalene additive had a good performance with Chongqing coal species. The dosage of additive changed between P% and Q% with the species of different additives. But the effect of combination additives in preparation of coal slurry only displayed additive effect and the synergy effect wasn't distinct. Temperature had an important impact on the viscosity of coal slurry. By studying the relation of viscosity and temperature, the experiment calculated the regression equation of viscosity and temperature: y = ?529.77ln(x )+2686.4 .The optimum pH in preparation of coal slurry is K. What's more, this paper also initially researched the effect of particle size selection in perfomance of coal slurry., the conclusion was gained that when the ratio of 100-200 mesh and greater than 200 mesh was M:N ,the particle size selection was the better than any else combination plans.Finally, the paper researched that the influence of different sulphonated rate about lignin additive that was self-prepared in laboratory toward the perfomance of coal slurry, the result disclosed that the higher sulphonated rate of additive was not the better, it had an optimum value. |
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