固定流化床催化裂解多产丙烯工艺条件的研究

Catalytic Pyrolysis for Maximum Production of Propylene in Confined Fluidized Bed Reactor

在固定流化床反应器上,采用 LCC-200型多产低碳烯烃催化剂,以大庆常压渣油为原料,考察了反应温度、重时空速、催化剂与原料油的质量比(剂油比)、水蒸气与原料油的质量比(水油比)对催化裂解产物分布的影响,并与提升管反应器的催化裂解实验结果进行了对比。实验结果表明,反应温度和剂油比对低碳烯烃收率的影响较大,重时空速和水油比的影响相对较小;较高的反应温度有利于多产低碳烯烃,低碳烯烃收率随剂油比的增大存在最佳。值在620℃、剂油比4、重时空速10 h^(-1)、水油比0.10的优化反应条件下,丙烯收率约为18%,乙烯、丙烯和丁烯的总收率约为35%。在相似的操作条件下,采用固定流化床反应器时,干气、液化石油气、汽油和焦炭的收率比提升管反应器离,而油浆和柴油的收率低;同时,乙烯、丙烯和丁烯的总收率也低。

Experiments of catalytic pyrolysis were carried out in a confined fluidized bed reactor using Daqing atmospheric residue as raw material and LCC-200 as catalyst. The catalyst showed good performance in production of light olefins. Effects of reaction temperature, mass ratio of catalyst to oil, mass ratio of water to oil and WHSV on product distribution in catalytic pyrolysis were studied. Reaction temperature and mass ratio of catalyst to oil greatly influence the yields of light olefins, but mass ratio of water to oil and WHSV influence more lightly them. High reaction temperature is favorable to production of light olefins. The yields of light olefins arrive to maximum with increasing of mass ratio of catalyst to oil. Under optimal operation conditions：620 ℃,mass ratio of catalyst to oil 4,mass ratio of water to oil 0. 10 and WHSV 10 h^-1 ,propylene yield reaches about 18%, and yield of total gaseous olefins including ethylene, propylene and butylenes reaches about 35%. Experimental results from the confined fluidized bed and riser reactors under similar operating conditions were compared. Yields of dry gas ,liquefied petroleum gas ,gasoline and coke from confined fluidized bed reactor are higher than that from riser reactor,but yields of diesel oil and slurry oil are lower, and the total yield of ethylene, propylene and butylenes is also lower.