两段提升管催化裂化生产丙烯工艺

Two-Stage Riser Fluidized-Bed Catalytic Cracking Technology for Production of Propylene

采用小型提升管实验装置模拟两段提升管催化裂化(TSRFCC)工艺,在反应条件、操作方式和氢分配方面进行了研究。实验结果表明,停留时间对丙烯收率的影响最明显,提高剂油比是增产丙烯经济效益最好的措施。以大庆掺渣蜡油为原料,采用LCC-200型催化剂,二段提升管回炼一段“汽油+油浆”时,液化气和丙烯总收率分别为36.52%和16.30%,汽油和柴油总收率分别为26.11%和19.10%,表明TSRFCC工艺配合多产丙烯催化剂,可在生产丙烯的同时兼顾轻油收率和品质。第二段提升管回炼一段柴油不能显著提高丙烯收率,还会降低柴油总收率和品质。第一段提升管提供约70%的丙烯和第二段提升管的原料,因此TSRFCC工艺一段提升管需保持合适的转化深度。TSRFCC工艺的氢利用率可达89.82%,氢分配比较合理。

Two-stage riser fluidized-bed catalytic cracking （TSRFCC）technology was simulated through an experimental mini-riser apparatus to seek the way of increasing yield of propylene in petroleum refining process. Effects of reaction conditions, operation mode and hydrogen distribution on yield of propylene were studied. Residence time is a main factor affecting propylene yield and increase of catalyst/oil ratio is preferential to raise of propylene yield. Using Daqing wax oil mixed with residue as feedstock and LCC-200 as catalyst, gasoline and slurry produced in the first riser were recycled to the second riser, yields of liquefied petroleum gas and propylene can reach 36.52% and 16.30% respectively. Yields of gasoline and diesel oil can reach 26.11% and 19.10% respectively. The utilization rate of hydrogen in TSRFCC process for maximizing propylene can reach 89.82%.