工艺条件对艾丁褐煤催化液化反应性研究

Study on process conditions on reactivity of catalytic liquefaction of Aiding lignite

为研究艾丁褐煤在直接液化中的反应性,通过水平震荡式高压釜对艾丁褐煤直接加氢液化进行试验研究,考察了反应温度、停留时间和氢气初压对艾丁褐煤直接液化的反应性能影响。结果表明,艾丁褐煤加氢液化反应适宜的反应条件为:反应温度430℃,反应时间60 min,氢气初压8.5 MPa,催化剂添加量1%(Fe/daf煤),溶煤比(质量比)为55∶45;提高反应温度、氢气初压和停留时间有利于增加油产率和转化率,其中氢气初压对转化率的影响相对较小;沥青烯产率随反应温度和氢气初压的升高呈先增加后降低的趋势,沥青烯随停留时间的延长呈降低趋势;前沥青烯产率随反应温度、氢气初压和停留时间的延长呈降低趋势;沥青烯和前沥青烯均呈现出中间产物的特征,反应温度、氢气初压和停留时间的提高有利于其向油气小分子转化。残煤中的Cdaf、H daf和H/C原子比随反应温度升高呈降低趋势,氢含量越高越易液化,随反应温度提高,氢含量较低的惰性结构难以液化,成为残煤中的主要组分;残煤中Cdaf、Ndaf和N/C原子比随反应温度的升高呈降低趋势,反应温度达到430℃时,残煤中的N/C原子比变化显著,煤中含氮结构加氢性能显著,脱氮能力明显提高。

In order to study the reactivity of Aiding lignite in direct liquefaction,the direct liquefaction of Aiding lignite was studied in the horizontal oscillating autoclave.The effects of reaction temperature,reaction time and H 2 initial pressure on the direct liquefaction reactivity of Aiding lignite were investigated.The results show that the suitable reaction conditions of Aiding lignite liquefaction are as follows:reaction temperature is 430℃,reaction time is 60 min,initial hydrogen pressure is 8.5 MPa,catalyst addition is 1%(Fe/daf coal),solvent to coal ratio(weight ratio)is 55∶45;The increase of reaction temperature,initial hydrogen pressure and reaction time can promote the increase of oil yield and conversion,and the effect of initial hydrogen pressure on conversion is relatively small.The yield of asphaltene first increases and then decreases with the increase of reaction temperature and hydrogen initial pressure,and decreases with the increase of reaction time.With the increase of reaction temperature,hydrogen initial pressure and residence time,the yield of preasphaltene decreases.Asphaltene and preasphaltene have the characteristics of intermediate products,and the increase of reaction temperature,hydrogen initial pressure and reaction time is favorable for the conversion to oil and gas.The Cdaf,H daf and the ratio of H/C atoms in residual coal decrease with the increase of reaction temperature.The higher the hydrogen content in coal is,the easier it is to liquefy.With the increase of reaction temperature,the inert structure with lower hydrogen content is difficult to liquefy and becomes the main component of residual coal.The Cdaf,H daf and the ratio of N/C atoms in residual coal decrease with the increase of reaction temperature,When the reaction temperature reaches 430℃,the ratio of N/C atoms in residual coal changes significantly,the hydrogenation performance of nitrogenous structure in coal is remarkable,and the denitrogenation ability is improved obviously.