世界首套焦化装置油浆加热炉的运行与检修

Operation and Maintenance of the World’s First Slurry Heating Furnace in Coking Unit

我国重油加工工艺基本上为脱碳过程,主要是馏分油催化裂化、热裂化、溶剂脱沥青、延迟焦化等,馏分油催化裂化是目前我国最主要的重油加工提高轻质油收率的手段。重油催化裂化装置产生的副产物催化油浆,常规的处理方式是送至延迟焦化装置,与减压渣油按一定的比例混合,作为延迟焦化装置的原料进行热裂化加工,而在延迟焦化装置实际生产中,因催化油浆中含固体催化剂颗粒,对设备和管线冲蚀严重,且催化油浆的固体颗粒作为结焦因子,加快了焦化加热炉炉管的结焦和结垢,故一般催化油浆的掺炼比例不超过减压渣油的5%。2016年SEI提出"油浆单独加热/炉后混炼"技术方案,该方案设置专门的油浆加热炉,减压渣油和催化油浆分别单独进装置、分别单独加热。该工艺下的首套装置在2019年10月22日于惠州石化延迟焦化装置一次开车成功,平稳运行达11月,远大于设计开工周期(6个月),油浆炉的平稳运行已成为惠州石化新利润增长点。

China’s heavy oil processing technology is basically a decarburization process and mainly includes distillate oil catalytic cracking,thermal cracking,solvent deasphalting and delayed coking.Among them,distillate oil catalytic cracking is the most important heavy oil processing method in China to improve the yield of light oil.FCC slurry,the by-product of heavy oil catalytic cracking unit,is conventionally sent to delayed coking unit to be mixed with vacuum residue according to a certain proportion for thermal cracking in the delayed coking unit as raw materials.In the actual production of delayed coking unit,the solid catalyst particles contained in the FCC slurry cause serious erosion of equipment and pipelines,and the solid particles of FCC slurry accelerate the coking and scaling of coking furnace tubes as a coking factor,so generally the blending ratio of FCC slurry is less than 5%of the vacuum residue.In 2016,SEI proposed a technical scheme of separate heating of FCC slurry and post-furnace mixing,in which a special slurry heating furnace is installed and the vacuum residue and FCC slurry are separately fed into the unit and separately heated.The first unit adopting this process has been operated smoothly for 11 months after it was successfully started up at the first try in the delayed coking unit of Huizhou Petrochemical Company on October 22,2019,much longer than the design on-stream period(6 months).The smooth operation of the slurry heating furnace has become a new profit growth point for Huizhou Petrochemical Company.