建立在多区协同控制新理念基础上的重油催化裂化MZCC(A Milti.Zone Cascade.Controlled FCC Process)技术,以优化油剂混合热量为工艺基础,提出了进料强返混、反应平流推进、产物超快分离及化学汽提的分区强化新方法。为了实施该技术,采用连续反应-再生提升管催化裂化中型试验装置,考察了强化油剂混合条件对重油催化裂化反应过程产物分布的影响规律,对MZCC技术的工艺基础进行了详细的研究。研究结果表明,降低再生催化剂温度,提高剂油比,在减少再生催化剂与原料接触温差的条件下提供适当的油剂混合热量,有利于提高提升管反应器内催化剂活性中心与原料的可接近性,强化烃分子与催化剂之间的热量和物质传递,从而更加有效地实现对大分子烃类的裂化反应,在相同转化率下可大幅度减少干气的产率,获得更高的轻质油收率和液体产品收率。
The MZCC (Multi-zone Cascade-Controlled FCC Process) process, which is based on the new concept of the multi-zone synergetic-control and the optimization of mixing heat of oil and catalyst, offers the novel technologies of intensively back mixing of feed zone, plug flow of reaction, super-rapid separation of oil vapor and catalyst, and chemical stripping of spent-catalyst. To investigate the impact of the improvement of the mixing heat of oil and catalyst on the product distribution in MZCC process and to have a detailed study on MZCC technologies, the experiments of residue catalytic cracking were performed on a riser pilot plant. The experimental results show that reduced regenerated catalyst temperature, increased catalyst-to-oil ratio and the optimization of catalyst oil mixing heat under the conditions of reduced differential temperature between regen- erated catalyst and feedstock are beneficial to improve catalytic active sites accessibility and heat and mass transfer between hydrocarbon molecules and catalysts. The yields of light oil and liquid are obviously increased with lower dry gas production at the same conversion.