This paper describes a mathematical model developed to study the behavior of liquefied petroleum gas (LPG) tanks when subjected to jet fire. The model consists of a number of field and zone sub-models which are used t...This paper describes a mathematical model developed to study the behavior of liquefied petroleum gas (LPG) tanks when subjected to jet fire. The model consists of a number of field and zone sub-models which are used to simulate the various physical phenomena taking place during the tank engulfment period. The model can be used to predict the pressure and temperature of the LPG in the tank, the temperature of the wall of tank, and the time of tank explosion. The comparisons between the model predicted results and the test data show good agreement. The results show that the jet fire partially impinging on tank wall led to higher wall temperature and the time to failure was shorter than that in engulfing pool fire. And the exposure of the upper wall in the vapor zone to the fire is more dangerous than that of the LPG contacted wall.展开更多
Tourmaline was modified with cerous nitrate and lanthanum nitrate by coprecipitation method. Through characterization by differential thermal analysis, transmission electron microscopy, X-ray diffraction, and Fourier ...Tourmaline was modified with cerous nitrate and lanthanum nitrate by coprecipitation method. Through characterization by differential thermal analysis, transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy, it was found that the tourmaline modified with La-doped nano-CeOhad a better far infrared emitting property than the tourmaline modified with CeO2, which depended on La enhancing the redox properties of CeO, leaded to much more oxidation of Fe2+ to Fe3+ in the tourmaline. Based on the results of the water boiling test, it was found that the tourmaline modified with La-doped nano-CeOcould decrease the consumption of liquefied petroleum gas, which resulted from the tourmaline modified with La-doped nano-CeOdecreasing the molecular clusters volume of liquefied petroleum gas and combustion-supporting air.展开更多
The reaction heat effect analysis for the aromatization process of Liquefied Petroleum Gas (LPG) was completed in this paper. In order to characterize this complex reaction system, one set of independent reactions was...The reaction heat effect analysis for the aromatization process of Liquefied Petroleum Gas (LPG) was completed in this paper. In order to characterize this complex reaction system, one set of independent reactions was determined by means of atomic coefficient matrix method. Based on reaction thermodynamic and stoichiometric knowledge, the heat effect, Gibbs free energy change and equilibrium constant for each independent reaction was calculated for the specified conditions. Under these conditions, based on the initial and final composition data from LPG aromatization experiments, the actual extent of reaction for each independent reaction was determined. Furthermore, the global reaction heat and adiabatic temperature rise of LPG aromatization reaction system could be estimated. This work would provide a theoretical guidance for the design and scale-up of reactor for LPG aromatization process, as well as for the selection of proper operating conditions.展开更多
A liquefied petroleum gas (LPG) sensor with high selectivity, sensitivity and low power consumption has been developed based on indium oxide with very low resistance. Nanocrystalline In203 gas sensing materials were...A liquefied petroleum gas (LPG) sensor with high selectivity, sensitivity and low power consumption has been developed based on indium oxide with very low resistance. Nanocrystalline In203 gas sensing materials were directly synthesized through a one-step controllable solvothermal process at 210 ℃ for 24 h, using InCI3.4H2O as the starting material, cetyltrimethyl ammonium bromide (CTAB) as additive and ethanol as the solvent. The obtained samples were characterized by X-ray diffraction (XRD), and transmission electron microscopy (TEM). The results showed that indium oxide takes on uniform cubic shape with range size of 10~30 nm and fine dispersivity. Gas sensitivity was measured in a mixing static gas. The results indicated that 3.0 V is the best working voltage of the sensor to LPG. Sensitivity is 12.6. The response-time and recovery-time are 3 s and 10 s respectively. Power consumption is only around 200 mW.展开更多
Temperature distribution and control have been investigated in a liquefiedpetroleum gas (LPG) fluidized bed with hollow corundum spheres (A1_2O_3) of 0.867-1.212 mm indiameter at moderately high temperatures (800-1100...Temperature distribution and control have been investigated in a liquefiedpetroleum gas (LPG) fluidized bed with hollow corundum spheres (A1_2O_3) of 0.867-1.212 mm indiameter at moderately high temperatures (800-1100℃). Experiments were carried out for the airconsumption coefficient α in the range of 0.3 to 1.0 and the fluidization number N in the range of1.3 to 3.0. Particle properties, initial bed height, α and N all affect temperature distribution inthe bed. Bed temperature can be adjusted about 200℃ by combined the adjusting of α and N.展开更多
This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtig...This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space.展开更多
This paper presents a quantitative risk analysis of liquefied petroleum gas(LPG)transportation.An accident that happened on June 13,2020,on the highway near Wenling,China is studied as a case.In this accident,LPG carr...This paper presents a quantitative risk analysis of liquefied petroleum gas(LPG)transportation.An accident that happened on June 13,2020,on the highway near Wenling,China is studied as a case.In this accident,LPG carried by a tank truck on the highway leaked and caused a large explosion,which led to 20 deaths.Different methods are combined to calculate the consequence of the accident.Multi-energy model and rupture of vessel model are employed to calculate the overpressure;the simulation result of the multi-energy model is closer to the damage caused by the accident.The safety distances in accidents of LPG transport storage tanks of different capacities are calculated in this study;the results show that the damage of explosion will increase with the filling degree of the tank.Even though the filling degree is 90%(value required by law),the 99%fatality rate range will reach 42 m,which is higher than regulated distance between road and building.The social risk of the tank truck has also been calculated and the results show that the risk is not acceptable.The calculating method used in this study could evaluate the risk of LPG tanker more accurately,which may contribute to the establishment of transportation regulation so that losses from similar accidents in the future could be reduced.展开更多
With the widespread application of liquefied petroleum gas (LPG),the safety of LPG cylinder has received more and more attention.For the safety of LPG cylinder,we conduct a safety risk assessment of cylinder using the...With the widespread application of liquefied petroleum gas (LPG),the safety of LPG cylinder has received more and more attention.For the safety of LPG cylinder,we conduct a safety risk assessment of cylinder using the failure mode and effect analysis (FMEA) method.Taking the most influential inflatable fatigue under normal conditions as the research object,we use FE-safe software to analyze the fatigue failure.The risk compliance coefficients of various failure modes are calculated and classified according to the risk level.In this way,the service life of the LPG cylinder weld is determined.The presented method improves the safety risk assessment process of LPG cylinder and provides a good theoretical and practical basis for similar pressure vessel risk assessment.展开更多
Direct synthesis of liquefied petroleum gas (LPG) from syngas was carried out over hybrid catalyst consisting of methanol synthesis catalyst and modified Y zeolite with Pd and Ca by different methods. The decrease o...Direct synthesis of liquefied petroleum gas (LPG) from syngas was carried out over hybrid catalyst consisting of methanol synthesis catalyst and modified Y zeolite with Pd and Ca by different methods. The decrease of CO conversion was mostly attributable to the sintering of Cu in methanol synthesis catalyst. On the other hand, coke deposition on Y zeolite was the reason for the decrease of LPG selectivity. The introduction of Ca decreased the strong acid sites of Y zeolite, suppressed coke formation, and thus improved the stability of hybrid catalyst.展开更多
Underground storage in rock caverns is widely used in Norway for many different petroleum products,such as crude oil,fuel,propane and butane.Basically,the caverns for such storages are unlined,i.e.containment is ensur...Underground storage in rock caverns is widely used in Norway for many different petroleum products,such as crude oil,fuel,propane and butane.Basically,the caverns for such storages are unlined,i.e.containment is ensured without using any steel lining or membrane.The main basis for the storage technology originates from the extensive hydropower development in Norway.As part of this activity,about 4500 km of tunnels and shafts have been excavated,and around 200 large powerhouse caverns have been constructed.The hydropower tunnels are mainly unlined,with hydrostatic water pressure on unlined rock of up to 1000 m.Some of the projects also include air cushion chambers with volumes of up to 1×10^(5)m^(3)and air pressure up to 7.7 MPa.Many lessons which are valuable also for underground oil and gas storage have been learnt from these projects.For a storage project to become successful,systematic,well planned design and ground investigation procedures are crucial.The main steps of the design procedure are first to define the optimum location of the project,and then to optimize orientation,shape/geometry and dimensions of caverns and tunnels.As part of the procedure,ground investigations have to be carried out at several steps integrated with the progress of design.The investigation and design procedures,and the great significance of these for the project to become successful will be discussed.Case examples of oil and gas storage in unlined rock caverns are given,illustrating the relevancy of experience from high-pressure hydropower projects for planning and design of unlined caverns for oil and gas storage.展开更多
Enlarging the fleet of gas carriers would make it possible to respond to the growing demand for hydrocarbon gases,but it will increase carbon dioxide emissions.The International Maritime Organization(IMO)has developed...Enlarging the fleet of gas carriers would make it possible to respond to the growing demand for hydrocarbon gases,but it will increase carbon dioxide emissions.The International Maritime Organization(IMO)has developed the energy efficiency design index(EEDI)with the objective of carbon emission reduction for new ships.In this paper,thirty gas carriers transporting liquefied natural gas(LNG)and liquefied petroleum gas(LPG)and equipped with various types of main engines are considered.As shown by the calculation of the attained EEDI,2 of the 13 LPG carriers and 6 of the 17 LNG carriers under study do not comply with the EEDI requirements.To meet the stringent EEDI requirements,applying thermochemical regenerators(TCRs)fed by main engine exhaust gases is suggested.Mathematical modeling is applied to analyze the characteristics of the combined gas-turbine-electric and diesel-electric power plant with thermochemical recuperation of the exhaust gas heat.Utilizing TCR on gas carriers with engines fueled by syngas produced from boil-off gas(BOG)reduces the carbon content by 35%and provides the energy efficiency required by IMO without the use of other technologies.展开更多
In order to present a retrospective analysis of exposition accidents using input data from investigation processes,data from a specific accident was examined,in which we analyzed possible involved gas species( liquef...In order to present a retrospective analysis of exposition accidents using input data from investigation processes,data from a specific accident was examined,in which we analyzed possible involved gas species( liquefied petroleum gas; nature gas) and computed their concentrations and distributions based on the interactions between the structures and the effects of the explosion. In this study,5 scenarios were created to analyze the impact effect. Moreover,a coupling algorithm was put into practice,with a practical outflow boundary and joint strength are applied. Finally,the damage effects of each scenario were simulated. Our experimental results showed significant differences in the 5 scenarios concerning the damage effects on the building structures. The results from scenario 3 agree with the accident characteristics,demonstrating the effectiveness of our proposed modeling method. Our proposed method reflects gas properties,species and the concentration and distribution,and the simulated results validates the root cause,process,and consequences of accidental explosions. Furthermore,this method describes the evolution process of explosions in different building structures. Significantly,our model demonstrates the quantatative explosion effect of factors like gas species,gas volumes,and distributions of gases on explosion results. In this study,a feasible,effective,and quantitative method for structure safety is defined,which is helpful to accelerate the development of safer site regulations.展开更多
Currently, thermal decomposition of hydrocarbons for the production of basic petrochemicals(ethylene, propylene) is carried out in steam-cracking processes. Aside from the conventional method, under consideration are ...Currently, thermal decomposition of hydrocarbons for the production of basic petrochemicals(ethylene, propylene) is carried out in steam-cracking processes. Aside from the conventional method, under consideration are alternative ways purposed for process intensification. In the context of these activities, the method of hightemperature pyrolysis of hydrocarbons in a heat-carrier flow is studied, which differs from previous ones and is based on the ability of an ultra-short time of feedstock/heat-carrier mixing. This enables to study the pyrolysis process at high temperature(up to 1500 K) at the reactor inlet. A set of model experiments is conducted on the lab scale facility. Liquefied petroleum gas(LPG) and naphtha are used as a feedstock. The detailed data are obtained on temperature and product distributions within a wide range of the residence time. A theoretical model based on the detailed kinetics of the process is developed, too. The effect of governing parameters on the pyrolysis process is analyzed by the results of the simulation and experiments. In particular, the optimal temperature is detected which corresponds to the maximum ethylene yield. Product yields in our experiments are compared with the similar ones in the conventional pyrolysis method. In both cases(LPG and naphtha), ethylene selectivity in the fast-mixing reactor is substantially higher than in current technology.展开更多
Domestic economic growth slowed down and supply exceeded demand in oil market in 2015, so the growth of refineries" processing volume was limited. Nevertheless, the gradual decontrol of market and the storage require...Domestic economic growth slowed down and supply exceeded demand in oil market in 2015, so the growth of refineries" processing volume was limited. Nevertheless, the gradual decontrol of market and the storage requirement under low oil price, crude oil imports hit a record high of 335.5 million tons, with the growth rate approximating 9%. Refined oil exports soared and imports decreased, which made China become a net refined oil exporter for the first time for 24 years, and net imports reached 6.22 million tons. Robust requirement on chemical raw materials propelled imported liquefied petroleum gas market to go on expanding. Imports exceeded 12 ,zillion tons in 2015, thus China leaped into the world's largest liquefied petroleum gas importer. In 2016, oil consumption growth would be kept at lower level. However, China would further decontrol crude oil import and refined oil export permits and put incremental storage capacity, into use. Therefore, crude oil imports would continue to rise up, and refined oil exports may hit a new historic high. hnported liquefied petroleum gas market will enter into a stage of stable growth after two years rapid development.展开更多
In 2016,China's net imports of crude oil increased to 378.3 million tons and its net exports of product oil soared to 20.45 million tons.Refinery crude runs continue to grow at a low rate,and the domestic product ...In 2016,China's net imports of crude oil increased to 378.3 million tons and its net exports of product oil soared to 20.45 million tons.Refinery crude runs continue to grow at a low rate,and the domestic product oil market still has a supply surplus.Diesel consumption fell for the first time in 21 years.The liquefied petroleum gas(LPG) market continues to grow rapidly,spurred on by feedstock demand for chemicals and gasoline blending components,and imports of LPG have reached a record high of 16.12 million tons.The refinery throughput of Petro China and SINOPEC had declined for 2 consecutive years,but crude oil imports climbed to a new high of 381 million tons as independent refineries boosted their utilization of capacity and the domestic oilfields produced a decreased amount of output.Imported oil now accounts for more than 2/3 of the Chinese market compared to being only about 1/3 15 years ago.Moreover,the proportion of imported crude in refinery runs has risen to 70%.In 2017,China's economy will continue to face substantial pressure,and domestic demand for product oil will continue to grow slowly.展开更多
China's oil import dependence had risen to 72% in 2017, while its net imports of various oil products, including crude oil, refined oil, liquefied petroleum gas (LPG) and other products, had climbed to 418.8 millio...China's oil import dependence had risen to 72% in 2017, while its net imports of various oil products, including crude oil, refined oil, liquefied petroleum gas (LPG) and other products, had climbed to 418.8 million tons, an increase by10.7% over 2016. China's crude oil import reached 420 million tons, surpassed the United States for the first time, and China had become the biggest crude oil importing country in the world. Net export of the rejqned oil, mainly the diesel, continued to increase to 22.7 million tons, as driven by the oversupply situation of the domestic market. Last year, China's LPG import was 18.45 million tons, but its growth was diminishing. Oil price would continue to rise in 2018, while the domestic demand of refined oil would be maintained at a lower rate of growth. However, driving by new refining capacities to be brought online, it is estimated that the crude oil import would still be increased remarkably. LPG import would reach a new high due to the growth potential and strong demand for feedstocks in the petrochemical product market.展开更多
文摘This paper describes a mathematical model developed to study the behavior of liquefied petroleum gas (LPG) tanks when subjected to jet fire. The model consists of a number of field and zone sub-models which are used to simulate the various physical phenomena taking place during the tank engulfment period. The model can be used to predict the pressure and temperature of the LPG in the tank, the temperature of the wall of tank, and the time of tank explosion. The comparisons between the model predicted results and the test data show good agreement. The results show that the jet fire partially impinging on tank wall led to higher wall temperature and the time to failure was shorter than that in engulfing pool fire. And the exposure of the upper wall in the vapor zone to the fire is more dangerous than that of the LPG contacted wall.
基金the Key Technologies R &D Programme of Tianjin (06YFGZGX02400)
文摘Tourmaline was modified with cerous nitrate and lanthanum nitrate by coprecipitation method. Through characterization by differential thermal analysis, transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy, it was found that the tourmaline modified with La-doped nano-CeOhad a better far infrared emitting property than the tourmaline modified with CeO2, which depended on La enhancing the redox properties of CeO, leaded to much more oxidation of Fe2+ to Fe3+ in the tourmaline. Based on the results of the water boiling test, it was found that the tourmaline modified with La-doped nano-CeOcould decrease the consumption of liquefied petroleum gas, which resulted from the tourmaline modified with La-doped nano-CeOdecreasing the molecular clusters volume of liquefied petroleum gas and combustion-supporting air.
文摘The reaction heat effect analysis for the aromatization process of Liquefied Petroleum Gas (LPG) was completed in this paper. In order to characterize this complex reaction system, one set of independent reactions was determined by means of atomic coefficient matrix method. Based on reaction thermodynamic and stoichiometric knowledge, the heat effect, Gibbs free energy change and equilibrium constant for each independent reaction was calculated for the specified conditions. Under these conditions, based on the initial and final composition data from LPG aromatization experiments, the actual extent of reaction for each independent reaction was determined. Furthermore, the global reaction heat and adiabatic temperature rise of LPG aromatization reaction system could be estimated. This work would provide a theoretical guidance for the design and scale-up of reactor for LPG aromatization process, as well as for the selection of proper operating conditions.
基金supported by the National Natural Science Foundation of China (Grant No.20471055)
文摘A liquefied petroleum gas (LPG) sensor with high selectivity, sensitivity and low power consumption has been developed based on indium oxide with very low resistance. Nanocrystalline In203 gas sensing materials were directly synthesized through a one-step controllable solvothermal process at 210 ℃ for 24 h, using InCI3.4H2O as the starting material, cetyltrimethyl ammonium bromide (CTAB) as additive and ethanol as the solvent. The obtained samples were characterized by X-ray diffraction (XRD), and transmission electron microscopy (TEM). The results showed that indium oxide takes on uniform cubic shape with range size of 10~30 nm and fine dispersivity. Gas sensitivity was measured in a mixing static gas. The results indicated that 3.0 V is the best working voltage of the sensor to LPG. Sensitivity is 12.6. The response-time and recovery-time are 3 s and 10 s respectively. Power consumption is only around 200 mW.
基金This work was financially suppoded by the Key Project Foundation for Science and Technology Research by the Education Ministry of China (No.00020).
文摘Temperature distribution and control have been investigated in a liquefiedpetroleum gas (LPG) fluidized bed with hollow corundum spheres (A1_2O_3) of 0.867-1.212 mm indiameter at moderately high temperatures (800-1100℃). Experiments were carried out for the airconsumption coefficient α in the range of 0.3 to 1.0 and the fluidization number N in the range of1.3 to 3.0. Particle properties, initial bed height, α and N all affect temperature distribution inthe bed. Bed temperature can be adjusted about 200℃ by combined the adjusting of α and N.
文摘This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space.
基金the Research Project of National Engineering Research Center for Petroleum Refining Technology and Catalyst(RIPP,SINOPEC)the National Key Research and Development Program of China(No.2018YFC0808600)。
文摘This paper presents a quantitative risk analysis of liquefied petroleum gas(LPG)transportation.An accident that happened on June 13,2020,on the highway near Wenling,China is studied as a case.In this accident,LPG carried by a tank truck on the highway leaked and caused a large explosion,which led to 20 deaths.Different methods are combined to calculate the consequence of the accident.Multi-energy model and rupture of vessel model are employed to calculate the overpressure;the simulation result of the multi-energy model is closer to the damage caused by the accident.The safety distances in accidents of LPG transport storage tanks of different capacities are calculated in this study;the results show that the damage of explosion will increase with the filling degree of the tank.Even though the filling degree is 90%(value required by law),the 99%fatality rate range will reach 42 m,which is higher than regulated distance between road and building.The social risk of the tank truck has also been calculated and the results show that the risk is not acceptable.The calculating method used in this study could evaluate the risk of LPG tanker more accurately,which may contribute to the establishment of transportation regulation so that losses from similar accidents in the future could be reduced.
文摘With the widespread application of liquefied petroleum gas (LPG),the safety of LPG cylinder has received more and more attention.For the safety of LPG cylinder,we conduct a safety risk assessment of cylinder using the failure mode and effect analysis (FMEA) method.Taking the most influential inflatable fatigue under normal conditions as the research object,we use FE-safe software to analyze the fatigue failure.The risk compliance coefficients of various failure modes are calculated and classified according to the risk level.In this way,the service life of the LPG cylinder weld is determined.The presented method improves the safety risk assessment process of LPG cylinder and provides a good theoretical and practical basis for similar pressure vessel risk assessment.
基金supported by the National Key Technology R & D Program of China(No.2011BAD22B06)BP Company through the Clean Energy Facing the Future Program at Dalian Institute of Chemical Physics
文摘Direct synthesis of liquefied petroleum gas (LPG) from syngas was carried out over hybrid catalyst consisting of methanol synthesis catalyst and modified Y zeolite with Pd and Ca by different methods. The decrease of CO conversion was mostly attributable to the sintering of Cu in methanol synthesis catalyst. On the other hand, coke deposition on Y zeolite was the reason for the decrease of LPG selectivity. The introduction of Ca decreased the strong acid sites of Y zeolite, suppressed coke formation, and thus improved the stability of hybrid catalyst.
文摘Underground storage in rock caverns is widely used in Norway for many different petroleum products,such as crude oil,fuel,propane and butane.Basically,the caverns for such storages are unlined,i.e.containment is ensured without using any steel lining or membrane.The main basis for the storage technology originates from the extensive hydropower development in Norway.As part of this activity,about 4500 km of tunnels and shafts have been excavated,and around 200 large powerhouse caverns have been constructed.The hydropower tunnels are mainly unlined,with hydrostatic water pressure on unlined rock of up to 1000 m.Some of the projects also include air cushion chambers with volumes of up to 1×10^(5)m^(3)and air pressure up to 7.7 MPa.Many lessons which are valuable also for underground oil and gas storage have been learnt from these projects.For a storage project to become successful,systematic,well planned design and ground investigation procedures are crucial.The main steps of the design procedure are first to define the optimum location of the project,and then to optimize orientation,shape/geometry and dimensions of caverns and tunnels.As part of the procedure,ground investigations have to be carried out at several steps integrated with the progress of design.The investigation and design procedures,and the great significance of these for the project to become successful will be discussed.Case examples of oil and gas storage in unlined rock caverns are given,illustrating the relevancy of experience from high-pressure hydropower projects for planning and design of unlined caverns for oil and gas storage.
文摘Enlarging the fleet of gas carriers would make it possible to respond to the growing demand for hydrocarbon gases,but it will increase carbon dioxide emissions.The International Maritime Organization(IMO)has developed the energy efficiency design index(EEDI)with the objective of carbon emission reduction for new ships.In this paper,thirty gas carriers transporting liquefied natural gas(LNG)and liquefied petroleum gas(LPG)and equipped with various types of main engines are considered.As shown by the calculation of the attained EEDI,2 of the 13 LPG carriers and 6 of the 17 LNG carriers under study do not comply with the EEDI requirements.To meet the stringent EEDI requirements,applying thermochemical regenerators(TCRs)fed by main engine exhaust gases is suggested.Mathematical modeling is applied to analyze the characteristics of the combined gas-turbine-electric and diesel-electric power plant with thermochemical recuperation of the exhaust gas heat.Utilizing TCR on gas carriers with engines fueled by syngas produced from boil-off gas(BOG)reduces the carbon content by 35%and provides the energy efficiency required by IMO without the use of other technologies.
基金Supported by the National Natural Science Foundation of China(E041003)the Fundamental Research Funds for the Central Universities(FRF-TP-15-105A1)the Postdoctoral Science Foundation of China(2015M580049)
文摘In order to present a retrospective analysis of exposition accidents using input data from investigation processes,data from a specific accident was examined,in which we analyzed possible involved gas species( liquefied petroleum gas; nature gas) and computed their concentrations and distributions based on the interactions between the structures and the effects of the explosion. In this study,5 scenarios were created to analyze the impact effect. Moreover,a coupling algorithm was put into practice,with a practical outflow boundary and joint strength are applied. Finally,the damage effects of each scenario were simulated. Our experimental results showed significant differences in the 5 scenarios concerning the damage effects on the building structures. The results from scenario 3 agree with the accident characteristics,demonstrating the effectiveness of our proposed modeling method. Our proposed method reflects gas properties,species and the concentration and distribution,and the simulated results validates the root cause,process,and consequences of accidental explosions. Furthermore,this method describes the evolution process of explosions in different building structures. Significantly,our model demonstrates the quantatative explosion effect of factors like gas species,gas volumes,and distributions of gases on explosion results. In this study,a feasible,effective,and quantitative method for structure safety is defined,which is helpful to accelerate the development of safer site regulations.
文摘Currently, thermal decomposition of hydrocarbons for the production of basic petrochemicals(ethylene, propylene) is carried out in steam-cracking processes. Aside from the conventional method, under consideration are alternative ways purposed for process intensification. In the context of these activities, the method of hightemperature pyrolysis of hydrocarbons in a heat-carrier flow is studied, which differs from previous ones and is based on the ability of an ultra-short time of feedstock/heat-carrier mixing. This enables to study the pyrolysis process at high temperature(up to 1500 K) at the reactor inlet. A set of model experiments is conducted on the lab scale facility. Liquefied petroleum gas(LPG) and naphtha are used as a feedstock. The detailed data are obtained on temperature and product distributions within a wide range of the residence time. A theoretical model based on the detailed kinetics of the process is developed, too. The effect of governing parameters on the pyrolysis process is analyzed by the results of the simulation and experiments. In particular, the optimal temperature is detected which corresponds to the maximum ethylene yield. Product yields in our experiments are compared with the similar ones in the conventional pyrolysis method. In both cases(LPG and naphtha), ethylene selectivity in the fast-mixing reactor is substantially higher than in current technology.
文摘Domestic economic growth slowed down and supply exceeded demand in oil market in 2015, so the growth of refineries" processing volume was limited. Nevertheless, the gradual decontrol of market and the storage requirement under low oil price, crude oil imports hit a record high of 335.5 million tons, with the growth rate approximating 9%. Refined oil exports soared and imports decreased, which made China become a net refined oil exporter for the first time for 24 years, and net imports reached 6.22 million tons. Robust requirement on chemical raw materials propelled imported liquefied petroleum gas market to go on expanding. Imports exceeded 12 ,zillion tons in 2015, thus China leaped into the world's largest liquefied petroleum gas importer. In 2016, oil consumption growth would be kept at lower level. However, China would further decontrol crude oil import and refined oil export permits and put incremental storage capacity, into use. Therefore, crude oil imports would continue to rise up, and refined oil exports may hit a new historic high. hnported liquefied petroleum gas market will enter into a stage of stable growth after two years rapid development.
文摘In 2016,China's net imports of crude oil increased to 378.3 million tons and its net exports of product oil soared to 20.45 million tons.Refinery crude runs continue to grow at a low rate,and the domestic product oil market still has a supply surplus.Diesel consumption fell for the first time in 21 years.The liquefied petroleum gas(LPG) market continues to grow rapidly,spurred on by feedstock demand for chemicals and gasoline blending components,and imports of LPG have reached a record high of 16.12 million tons.The refinery throughput of Petro China and SINOPEC had declined for 2 consecutive years,but crude oil imports climbed to a new high of 381 million tons as independent refineries boosted their utilization of capacity and the domestic oilfields produced a decreased amount of output.Imported oil now accounts for more than 2/3 of the Chinese market compared to being only about 1/3 15 years ago.Moreover,the proportion of imported crude in refinery runs has risen to 70%.In 2017,China's economy will continue to face substantial pressure,and domestic demand for product oil will continue to grow slowly.
文摘China's oil import dependence had risen to 72% in 2017, while its net imports of various oil products, including crude oil, refined oil, liquefied petroleum gas (LPG) and other products, had climbed to 418.8 million tons, an increase by10.7% over 2016. China's crude oil import reached 420 million tons, surpassed the United States for the first time, and China had become the biggest crude oil importing country in the world. Net export of the rejqned oil, mainly the diesel, continued to increase to 22.7 million tons, as driven by the oversupply situation of the domestic market. Last year, China's LPG import was 18.45 million tons, but its growth was diminishing. Oil price would continue to rise in 2018, while the domestic demand of refined oil would be maintained at a lower rate of growth. However, driving by new refining capacities to be brought online, it is estimated that the crude oil import would still be increased remarkably. LPG import would reach a new high due to the growth potential and strong demand for feedstocks in the petrochemical product market.