The demand of hydrogen in oil refinery is increasing as market forces and environmental legislation, so hydrogen network management is becoming increasingly important in refineries. Most studies focused on single-obje...The demand of hydrogen in oil refinery is increasing as market forces and environmental legislation, so hydrogen network management is becoming increasingly important in refineries. Most studies focused on single-objective optimization problem for the hydrogen network, but few account for the multi-objective optimization problem. This paper presents a novel approach for modeling and multi-objective optimization for hydrogen network in refineries. An improved multi-objective optimization model is proposed based on the concept of superstructure. The optimization includes minimization of operating cost and minimization of investment cost of equipment. The proposed methodology for the multi-objective optimization of hydrogen network takes into account flow rate constraints, pressure constraints, purity constraints, impurity constraints, payback period, etc. The method considers all the feasible connections and subjects this to mixed-integer nonlinear programming （MINLP）. A deterministic optimization method is applied to solve this multi-objective optimization problem. Finally, a real case study is intro-duced to illustrate the applicability of the approach.展开更多
Inferior crude oil and fuel oil upgrading lead to escalating increase of hydrogen consumption in refineries.It is imperative to reduce the hydrogen consumption for energy-saving operations of refineries.An integration...Inferior crude oil and fuel oil upgrading lead to escalating increase of hydrogen consumption in refineries.It is imperative to reduce the hydrogen consumption for energy-saving operations of refineries.An integration strategy of hydrogen network and an operational optimization model of hydrotreating(HDT)units are proposed based on the characteristics of reaction kinetics of HDT units.By solving the proposed model,the operating conditions of HDT units are optimized,and the parameters of hydrogen sinks are determined by coupling hydrodesulfurization(HDS),hydrodenitrification(HDN)and aromatic hydrogenation(HDA)kinetics.An example case of a refinery with annual processing capacity of eight million tons is adopted to demonstrate the feasibility of the proposed optimization strategies and the model.Results show that HDS,HDN and HDA reactions are the major source of hydrogen consumption in the refinery.The total hydrogen consumption can be reduced by 18.9%by applying conventional hydrogen network optimization model.When the hydrogen network is optimized after the operational optimization of HDT units is performed,the hydrogen consumption is reduced by28.2%.When the benefit of the fuel gas recovery is further considered,the total annual cost of hydrogen network can be reduced by 3.21×10~7CNY·a^(-1),decreased by 11.9%.Therefore,the operational optimization of the HDT units in refineries should be imposed to determine the parameters of hydrogen sinks base on the characteristics of reaction kinetics of the hydrogenation processes before the optimization of the hydrogen network is performed through the source-sink matching methods.展开更多
Hydrogen network management is important to refineries. Various systematic management techniques have been developed to improve the efficiency of refinery hydrogen networks. However, existing methods all treat the hyd...Hydrogen network management is important to refineries. Various systematic management techniques have been developed to improve the efficiency of refinery hydrogen networks. However, existing methods all treat the hydrogen network separately. The tradeoff between hydrogen network cost and oil processing network benefit has not been explored in the hydrogen network management yet. A novel sensitivity analysis scheme is presented to take oil processing network into consideration. Oil processing unit which is sensitive to both oil processing networks and hydrogen networks is identified first. Then, sensitivity analysis of the unit around the operating point of oil processing networks and hydrogen networks is carried out. Finally, the overall optimal operating condition is obtained. An example of a real Chinese refinery demonstrates the effectiveness of the proposed analysis method.展开更多
In this research, the affect of storage time and different metals concentration of copper and iron on gum formation in gas oil is investigated. A study of the affect of gum content on properties of sample is performed...In this research, the affect of storage time and different metals concentration of copper and iron on gum formation in gas oil is investigated. A study of the affect of gum content on properties of sample is performed, where the gas oil derived from （Kirkuk crude oil） have boiling point range （266-420）℃. For this purpose, a gas oil sample has been doped with these two metals ions at concentration levels of 0.5, 1.5, 2.5 and 3.5 μg mL-1. Washed gum content tests have been carried out using ASTM D-381 on samples stored for 8, 16, 24 and 32 days. The experimental results show that an increase in storage time and metal concentration strongly increases the rate of gum formation for all metal investigations and this increase in gum concentration affects the viscosity of samples towards increasing of viscosity.展开更多
基金Supported by the National High Technology Research and Development Program of China （2008AA042902, 2009AA04Z162）, the Program of Introducing Talents of Discipline to University （B07031） and the National Natural Science Foundation of China （21106129）.
文摘The demand of hydrogen in oil refinery is increasing as market forces and environmental legislation, so hydrogen network management is becoming increasingly important in refineries. Most studies focused on single-objective optimization problem for the hydrogen network, but few account for the multi-objective optimization problem. This paper presents a novel approach for modeling and multi-objective optimization for hydrogen network in refineries. An improved multi-objective optimization model is proposed based on the concept of superstructure. The optimization includes minimization of operating cost and minimization of investment cost of equipment. The proposed methodology for the multi-objective optimization of hydrogen network takes into account flow rate constraints, pressure constraints, purity constraints, impurity constraints, payback period, etc. The method considers all the feasible connections and subjects this to mixed-integer nonlinear programming （MINLP）. A deterministic optimization method is applied to solve this multi-objective optimization problem. Finally, a real case study is intro-duced to illustrate the applicability of the approach.
基金Supported by the National Natural Science Foundation of China(21376188,21676211)the Key Project of Industrial Science and Technology of Shaanxi Province(2015GY095)
文摘Inferior crude oil and fuel oil upgrading lead to escalating increase of hydrogen consumption in refineries.It is imperative to reduce the hydrogen consumption for energy-saving operations of refineries.An integration strategy of hydrogen network and an operational optimization model of hydrotreating(HDT)units are proposed based on the characteristics of reaction kinetics of HDT units.By solving the proposed model,the operating conditions of HDT units are optimized,and the parameters of hydrogen sinks are determined by coupling hydrodesulfurization(HDS),hydrodenitrification(HDN)and aromatic hydrogenation(HDA)kinetics.An example case of a refinery with annual processing capacity of eight million tons is adopted to demonstrate the feasibility of the proposed optimization strategies and the model.Results show that HDS,HDN and HDA reactions are the major source of hydrogen consumption in the refinery.The total hydrogen consumption can be reduced by 18.9%by applying conventional hydrogen network optimization model.When the hydrogen network is optimized after the operational optimization of HDT units is performed,the hydrogen consumption is reduced by28.2%.When the benefit of the fuel gas recovery is further considered,the total annual cost of hydrogen network can be reduced by 3.21×10~7CNY·a^(-1),decreased by 11.9%.Therefore,the operational optimization of the HDT units in refineries should be imposed to determine the parameters of hydrogen sinks base on the characteristics of reaction kinetics of the hydrogenation processes before the optimization of the hydrogen network is performed through the source-sink matching methods.
基金financial supported by National Natural Science Foundation of China(No.20409205 & 60421002)National High Technology Research and Development Program of China(No.2007AA04Z191 & 2007AA040702)
文摘Hydrogen network management is important to refineries. Various systematic management techniques have been developed to improve the efficiency of refinery hydrogen networks. However, existing methods all treat the hydrogen network separately. The tradeoff between hydrogen network cost and oil processing network benefit has not been explored in the hydrogen network management yet. A novel sensitivity analysis scheme is presented to take oil processing network into consideration. Oil processing unit which is sensitive to both oil processing networks and hydrogen networks is identified first. Then, sensitivity analysis of the unit around the operating point of oil processing networks and hydrogen networks is carried out. Finally, the overall optimal operating condition is obtained. An example of a real Chinese refinery demonstrates the effectiveness of the proposed analysis method.
文摘In this research, the affect of storage time and different metals concentration of copper and iron on gum formation in gas oil is investigated. A study of the affect of gum content on properties of sample is performed, where the gas oil derived from （Kirkuk crude oil） have boiling point range （266-420）℃. For this purpose, a gas oil sample has been doped with these two metals ions at concentration levels of 0.5, 1.5, 2.5 and 3.5 μg mL-1. Washed gum content tests have been carried out using ASTM D-381 on samples stored for 8, 16, 24 and 32 days. The experimental results show that an increase in storage time and metal concentration strongly increases the rate of gum formation for all metal investigations and this increase in gum concentration affects the viscosity of samples towards increasing of viscosity.
