This article has summarized the optimized measures relating to the loading of catalyst,and the sixth operating cycle of the residue hydrotreating unit at SINOPEC's Maoming Branch Company,and made a detailed compar...This article has summarized the optimized measures relating to the loading of catalyst,and the sixth operating cycle of the residue hydrotreating unit at SINOPEC's Maoming Branch Company,and made a detailed comparison on the impurities removal rate,hydrogen consumption and energy consumption of the sixth operating cycle with those achieved by the previous five cycles.Test results have revealed that the second-generation RHT series novel residue hydrotreating catalysts featured high activity,good stability,and long operating cycle and could remarkably reduce the hydrogen consumption and energy consumption of process unit.The hydrotreated AR product,having low Conradson carbon residue,low sulfur content,low metal content,high content of saturated hydrocarbons,and low content of asphaltenes and resins,is an excellent FCC feed.Judging from their overall property the second-generation RHT series of residue hydrotreating catalysts used in the sixth operating cycle have commanded a leading position among other catalysts used in previous operating cycles.展开更多
The paper addresses the system performance of coal-fired power unit with changed auxiliary system or other local heat disturbance. The idea of state space model is imported and the universal formula for the calculatio...The paper addresses the system performance of coal-fired power unit with changed auxiliary system or other local heat disturbance. The idea of state space model is imported and the universal formula for the calculation of system performance output is deduced on the system state equation. Two important vector of system are worked out under linear system assumption and transform. The transfer matrix is the characteristics of system itself and is constant for a similar condition, which greatly facilitates the analysis. The concept of thermal disturbance vector is proposed to construct the thermal disturbance input easily. The method can be helpful for analyzing any thermal disturbance input satisfying the assumption and also for supplementing the correction means of performance test. An example of 600MW power unit is presented to demonstrate its availability.展开更多
Existing methods of obtaining runtime feedback for structure data-layout optimization have several drawbacks, such as large overhead and difficulty composing training sets. As a result, structure data-layout optimizat...Existing methods of obtaining runtime feedback for structure data-layout optimization have several drawbacks, such as large overhead and difficulty composing training sets. As a result, structure data-layout optimization is not widely used. To overcome these drawbacks, a performance monitoring unit （PMU） sampling method was developed with much less overhead and better portability and usability. An algorithm was developed to correct incomplete and inaccurate PMU sampling. With the corrected PMU feedback, a structure data-layout optimizer achieved a 45.1% performance improvement compared to a design without data-layout optimization, which is 97.6% of the performance improvement achieved with instrumented feedback. Calculation of the PMU feedback increased the execution time by 12.3%, compared to the overhead for the instrumented feedback of 341.5%. Tests show that the PMU feedback is efficient and effective for structure data-layout optimization.展开更多
The flow and thermal breakthrough phenomenon in a forced external circulation standing column well(FECSCW)directly affects heat transfer efficiency and load-carrying capacity.A numerical model for FECSCW is developed ...The flow and thermal breakthrough phenomenon in a forced external circulation standing column well(FECSCW)directly affects heat transfer efficiency and load-carrying capacity.A numerical model for FECSCW is developed to analyze the migration of the temperature and velocity front under the flow and thermal breakthrough.The results indicated that thermal breakthrough began after simulation running 2.5 min and was completely formed after 12 min.The inlet water,which directly entered the production well without heat exchange with the aquifer,accounted for 12.8%.When the porosity of the backfill material decreased from 0.35 to 0,the coefficient of per-formance(COP)of the heat pump unit increased by 1.6%on average,and the thermal breakthrough strength decreased by an average of 45.3%within 25 min.Where seepage velocity near the well wall was greater than 1×10^(−3) m·s^(−1),faster velocity front migration was observed,while the migration advantage of the temperature front was more prominent outside of this region.Through quantitative analysis of flow and thermal breakthrough,temperature and velocity front migration,and COP change of heat pump unit,theoretical suggestions were pro-vided for the thermal transfer mechanism near the thermal well wall.The extended research in this study can be applied to the design and optimization of forced external circulation standing column well system.展开更多
文摘This article has summarized the optimized measures relating to the loading of catalyst,and the sixth operating cycle of the residue hydrotreating unit at SINOPEC's Maoming Branch Company,and made a detailed comparison on the impurities removal rate,hydrogen consumption and energy consumption of the sixth operating cycle with those achieved by the previous five cycles.Test results have revealed that the second-generation RHT series novel residue hydrotreating catalysts featured high activity,good stability,and long operating cycle and could remarkably reduce the hydrogen consumption and energy consumption of process unit.The hydrotreated AR product,having low Conradson carbon residue,low sulfur content,low metal content,high content of saturated hydrocarbons,and low content of asphaltenes and resins,is an excellent FCC feed.Judging from their overall property the second-generation RHT series of residue hydrotreating catalysts used in the sixth operating cycle have commanded a leading position among other catalysts used in previous operating cycles.
文摘The paper addresses the system performance of coal-fired power unit with changed auxiliary system or other local heat disturbance. The idea of state space model is imported and the universal formula for the calculation of system performance output is deduced on the system state equation. Two important vector of system are worked out under linear system assumption and transform. The transfer matrix is the characteristics of system itself and is constant for a similar condition, which greatly facilitates the analysis. The concept of thermal disturbance vector is proposed to construct the thermal disturbance input easily. The method can be helpful for analyzing any thermal disturbance input satisfying the assumption and also for supplementing the correction means of performance test. An example of 600MW power unit is presented to demonstrate its availability.
文摘Existing methods of obtaining runtime feedback for structure data-layout optimization have several drawbacks, such as large overhead and difficulty composing training sets. As a result, structure data-layout optimization is not widely used. To overcome these drawbacks, a performance monitoring unit （PMU） sampling method was developed with much less overhead and better portability and usability. An algorithm was developed to correct incomplete and inaccurate PMU sampling. With the corrected PMU feedback, a structure data-layout optimizer achieved a 45.1% performance improvement compared to a design without data-layout optimization, which is 97.6% of the performance improvement achieved with instrumented feedback. Calculation of the PMU feedback increased the execution time by 12.3%, compared to the overhead for the instrumented feedback of 341.5%. Tests show that the PMU feedback is efficient and effective for structure data-layout optimization.
基金This work was supported by the National Natural Science Foundation of China(41002085,41602278)China Postdoctoral Science Founda-tion(2016M601129)North China University of Technology Programs(18XN154-006,110052972027-031).
文摘The flow and thermal breakthrough phenomenon in a forced external circulation standing column well(FECSCW)directly affects heat transfer efficiency and load-carrying capacity.A numerical model for FECSCW is developed to analyze the migration of the temperature and velocity front under the flow and thermal breakthrough.The results indicated that thermal breakthrough began after simulation running 2.5 min and was completely formed after 12 min.The inlet water,which directly entered the production well without heat exchange with the aquifer,accounted for 12.8%.When the porosity of the backfill material decreased from 0.35 to 0,the coefficient of per-formance(COP)of the heat pump unit increased by 1.6%on average,and the thermal breakthrough strength decreased by an average of 45.3%within 25 min.Where seepage velocity near the well wall was greater than 1×10^(−3) m·s^(−1),faster velocity front migration was observed,while the migration advantage of the temperature front was more prominent outside of this region.Through quantitative analysis of flow and thermal breakthrough,temperature and velocity front migration,and COP change of heat pump unit,theoretical suggestions were pro-vided for the thermal transfer mechanism near the thermal well wall.The extended research in this study can be applied to the design and optimization of forced external circulation standing column well system.
