Fixed bed residue hydrogenation technology is an important means of making heavy oil lighter. Coke deposition is one of the important reasons leading to catalyst deactivation and shorter running period of residue hydrogenation unit. The source of catalyst coke deposition,the type of coke, the mechanism of coke deposition,the factors affecting coke deposition and the methods to inhibit coke deposition are discussed and outlined. There are two types of coke deposition:soft coke and hard coke, mainly from dehydrogenative condensation reactions of polyaromatic species,such as asphaltene,and these substances adsorb on the catalyst surface easily. The properties of residue oil,catalyst physicochemical characteristics and process condition have important effect on coke formation. Lower viscosity residue oil,the catalyst with bigger pore size and higher hydrogen pressure can reduce coke content. Blending residue oil with low viscosity and high aromaticity distillate in the reaction process can effectively inhibit coke formation. The review provides reference for effectively controlling catalyst coke deposition and prolonging catalyst life time.%固定床渣油加氢技术是重质油轻质化的重要手段,积炭是造成催化剂失活、缩短渣油加氢装置运行周期的重要原因之一.本文介绍了固定床渣油加氢反应时催化剂积炭的来源、积炭类型及形成机理、影响积炭形成的因素、抑制催化剂积炭的方法.积炭分为软炭和硬炭,主要由渣油中的沥青质等稠合芳香环化合物吸附于催化剂表面脱氢缩合形成;渣油性质、催化剂物化性能和工艺条件共同影响积炭形成,低黏度渣油、大孔径催化剂及较高氢分压可以减少催化剂表面积炭量;反应过程中掺杂低黏度高芳香性馏分油可以较好地抑制积炭形成.文章指出通过对固定床渣油加氢催化剂积炭问题的分析,可以达到有效抑制催化剂表面积炭和延长催化剂运转周期的目的.
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