Research And Development Of Key Technologies For Crude Oil Deep Blending In Refining Processes

On-line crude oil blending is a key part in the process of petroleum production and processing.By means of on-line crude oil blending,the production cost can be reduced and the stability of processing equipment can be improved.Driven by the practical demands of crude oil processing,a comprehensive study of the key techniques of crude oil deep blending is conducted in this thesis to promote on-line crude oil blending properties.In the first chapter,the background,significance and the principle of crude oil blending technology,as well as the research status of crude oil on-line blending technology at home and abroad are introduced,and then some key problems of crude oil on-line blending are studied.In the second chapter,the rapid analysis method of crude oil fine properties by local distance weighting is studied on which the crude oil deep blending is based.The pretreatment method of near infrared spectrum is first determined in this chapter,and then the dynamic modeling method of fine properties of crude oil based on local distance weighting is proposed.In addition,some key parts are explained in detail,including the rule of selecting similar samples,the evaluation of uncertainty of oil properties,as well as the method of local distance weighting,etc.In the end,a case of rapid analysis of hydrocarbon group composition in crude oil of one refinery enterprise is studied and analyzed.The methods of crude oil selection and processing ratio optimization are studied in chapter three.First,the quality indicators of crude oil deep blending(including linear and non-linear,overall properties and fine properties)and technical requirements are analyzed.Then the crude oil deep blending model is established,and a particle swarm optimization algorithm solution based on the nonlinear optimization model of crude oil deep blending is proposed.This method changes the situation of traditional fixed blended crude oil and the overall property index.This method expands the range of crude oil selection,and successfully introduces fine properties as the control indicators in the blending model.Finally,an analysis is given about crude oil blending of 3# crude oil distillation unit(CDU)in a refinery enterprise in detail which verifies the methodological validity.In the fourth chapter,a dynamic blending method of crude oil is designed for processing scheme switching,and the deep blending process under complex technology is realized.The blending conditions under the switching of processing schemes are first analyzed,and then the dynamic blending scheme of crude oil with buffer tank is studied.This method not only modifies the deviation of bottom oil properties,but also effectively reduces the production fluctuation caused by scheme switching.Finally,a processing scheme switching operation of one refinery enterprise is studied,and the dynamic blending process of crude oil is analyzed in detail.In chapter five,a software platform for crude oil deep blending is designed and developed which includes rapid analysis,blending optimization and scheme switching,etc.First,the overall design scheme of the platform is proposed according to the production demands and key technology points.Then the functions of the platform are designed,including real-time database of crude oil,rapid analysis of fine properties,optimization of crude oil selection and blending,dynamic blending and property tracking.Finally,the software is developed and the operation effects of the platform are demonstrated,which shows that the application of key technologies of crude oil deep blending has met the needs of refinery enterprises.This thesis has valuable guidance and reference for the study and application of crude oil deep blending technologies.By the key technical means of crude oil deep blending,the utilization ratio of crude oil can be optimized,and the production plan and loads of the secondary processing units be reasonably arranged.While reducing the cost of crude oil,the processing efficiency is improved and the production benefit is maximized.In addition,the stability of CDU feeding properties can be enhanced to the greatest extent,and the processing operation of CDU can be improved.