The Simulation Study Of Hydro-cracking Distillation Process About CNOOC Huizhou Refinery

As crude oil is getting heavier and poorer,the demand of light oil is increasing with stringent environmental requirements.Heavy oil efficient utilization is an important subject of each oil refining enterprise.Supercritical extraction of vacuum residue can produce lighter and better de-asphalted oil,which can be blended into the decompressed wax oil and obtain a higher yield of light oil from hydrocracking reaction.According to the industrial hydrocracking distillation data of 4 million tons/year process in Huizhou Refinery,this thesis builded a simulation process with Aspen Plus software by taking the industrial products as the simulated feed,furthermore,the simulated results fitted well with the industrial data.As adding a pre-flasher between C201 stripper and C202 main fractionator,the duty of furnace and condenser were reduced significantly.In order to reduce the process load,the suitable operation temperature and pressure of flasher should be chosen by taking the inflection point of load curve into consideration,which would provide a new route for hydrocracking process energy conservation.Used the feedstocks of VGO with 10% and 20% light de-asphalted oil?LDAO?of Penglai and Dalia oils and adpoted the industrial hydrogenation catalyst offered by Huizhou Refinery,the hydrocracking performances were evaluated in a 10 m L fixed bed microreactor.The products obtained under the conditions of temperature 390 ?,pressure 9 MPa,space velocity of 1.0 h^-1 and hydrogen to oil ratio 1000 v/v were taken as the reference in the simulation process.Compared the simulated operation conditions,products distribution and flash optimization among the feeds of Penglai VGO,VGO blended 10% LDAO and VGO blended 20% LDAO,it could be found that,the plate temperatures of the stripper and main fractionation tower became higher while the gas-liquid load decreased with the increasing of blending ratio.When the feed was Penglai VGO blending 10% LDAO,the simulated operation conditions were consistent with industrial data and the total proportion of the target components of jet fuel and diesel reached 51.62%.For a long-term industrial operation,the recommended LDAO blending ratio with Penglai VGO was 10%.As a comparison,the simulated operation conditions,products distribution and flash optimization among the various feeds of Dalia VGO,VGO blended 10% LDAO and VGO blended 20% LDAO showed that as the feed was Dalia VGO blending 20% LDAO,the total proportion of the objective components of jet fuel and diesel could reach 45.15% and the gas-liquid load reached the lowest.For a long-term industrial smoothly operation,the recommended LDAO blending ratio with Dalia VGO was 20%.The comparision of simulation operating conditions with feedstocks of VGO,VGO blending 10% LDAO and VGO blending 20% LDAO of Penglai and Dalia oil will provide conditions adjustment scheme for these feedstocks performing on Huizhou industrial hydrocracking unit.The research data and laws in this paper will provide basic research data and information for the industrial operations with the scope of wide range raw material for the long period and smoothly running of Huizhou refinery hydrocracking unit.