In efforts to overcome an foreseeable energy crisis predicated on limited oil and gas supplies, reserves; economic variations facing the world, and of course the environmental side effects of fossil fuels, an urgent n...In efforts to overcome an foreseeable energy crisis predicated on limited oil and gas supplies, reserves; economic variations facing the world, and of course the environmental side effects of fossil fuels, an urgent need for energy sources that provide sustainable, safe and economic supplies for the world is imperative. The current fossil fuel energy system must be improved to ensure a better and cleaner transportation future for the world. Despite the fact that the marine transportation sector consumes only 5% of global petroleum production; it is responsible for 15% of the world NOx and SOx emissions. These figures must be the engine that powers the scientific research worldwide to develop new solutions for a very old energy problem. In this paper, the most effective types of marine power plants were discussed. The history of the development of each type was presented first and the technical aspects were discussed second. Also, the fuel ceils as a new type of power plants used in marine sector were briefed to give a complete overview of the past, present and future of the marine power plants development. Based on the increased worldwide concerns regarding harmful emissions, many researchers have introduced solutions to this problem, including the adoption of new cleaner fuels. This paper was guided using the same trend and by implementing the hydrogen as fuel for marine internal combustion engine, gas turbines, and fuel cells.展开更多
HFO-1234 ze(E)(trans-1,3,3,3-tetrafluoropropene,chemical formula:C3H2F4)is an extremely environmentally friendly SF6 alternative gas with high electrical strength.In this paper,the partial discharge(PD)characteristics...HFO-1234 ze(E)(trans-1,3,3,3-tetrafluoropropene,chemical formula:C3H2F4)is an extremely environmentally friendly SF6 alternative gas with high electrical strength.In this paper,the partial discharge(PD)characteristics of HFO-1234 ze(E)/N2 mixtures were studied using the gas insulation test platform.The PD inception voltage of insulating gas under positive and negative half cycles of power frequency was tested.Using SF6/N2 mixtures as a control group,the effects of electrode spacing,mixing ratio and pressure on the insulation performance of HFO-1234 ze(E)/N2 mixtures were explored.The test results show that the PD inception voltage of the negative half-cycle of pure HFO-1234 ze(E)under short electrode spacing can reach 0.96-1.04 times of pure SF6 under different pressures;the PD inception voltage of40%HFO-1234 ze(E)/60%N2 mixtures at 0.3 MPa is 0.67-0.89 times that of SF6/N2 mixtures under the same conditions,which has great application prospect.展开更多
The mitigation of the CO inhibition effect in palladium membranes is necessary due to its significance in the efficiency of membrane reactors and hydrogen production systems. In this work, the hydrogen separation perf...The mitigation of the CO inhibition effect in palladium membranes is necessary due to its significance in the efficiency of membrane reactors and hydrogen production systems. In this work, the hydrogen separation performance of a Pd and Pd/Ag membrane both of thickness 2 μm is investigated using a mixed gas with composition (H2 = 50%, CO = 28%, CO2 = 10%, CH4 = 8%, N2 = 4%) at temperature 623 - 873 K and pressure (0.05 - 0.4 bar) was investigated. The component gases CO and CO2 were observed to inhibit hydrogen permeation through the membrane and lead to deviations from Sievert’s law for n values 0.55 and 0.62 for the Pd membrane and unity for the Pd/Ag membrane. For the Pd/Ag membrane, the concentration of CO in the permeate stream was reduced as a result of the addition of Ag. The effect of the component gases to hydrogen permeation was observed to be lower for the Pd/Ag membrane. Annealing the membrane in hydrogen at high temperature decreased the inhibition effect and enhanced hydrogen permeation through the membrane.展开更多
文摘In efforts to overcome an foreseeable energy crisis predicated on limited oil and gas supplies, reserves; economic variations facing the world, and of course the environmental side effects of fossil fuels, an urgent need for energy sources that provide sustainable, safe and economic supplies for the world is imperative. The current fossil fuel energy system must be improved to ensure a better and cleaner transportation future for the world. Despite the fact that the marine transportation sector consumes only 5% of global petroleum production; it is responsible for 15% of the world NOx and SOx emissions. These figures must be the engine that powers the scientific research worldwide to develop new solutions for a very old energy problem. In this paper, the most effective types of marine power plants were discussed. The history of the development of each type was presented first and the technical aspects were discussed second. Also, the fuel ceils as a new type of power plants used in marine sector were briefed to give a complete overview of the past, present and future of the marine power plants development. Based on the increased worldwide concerns regarding harmful emissions, many researchers have introduced solutions to this problem, including the adoption of new cleaner fuels. This paper was guided using the same trend and by implementing the hydrogen as fuel for marine internal combustion engine, gas turbines, and fuel cells.
文摘HFO-1234 ze(E)(trans-1,3,3,3-tetrafluoropropene,chemical formula:C3H2F4)is an extremely environmentally friendly SF6 alternative gas with high electrical strength.In this paper,the partial discharge(PD)characteristics of HFO-1234 ze(E)/N2 mixtures were studied using the gas insulation test platform.The PD inception voltage of insulating gas under positive and negative half cycles of power frequency was tested.Using SF6/N2 mixtures as a control group,the effects of electrode spacing,mixing ratio and pressure on the insulation performance of HFO-1234 ze(E)/N2 mixtures were explored.The test results show that the PD inception voltage of the negative half-cycle of pure HFO-1234 ze(E)under short electrode spacing can reach 0.96-1.04 times of pure SF6 under different pressures;the PD inception voltage of40%HFO-1234 ze(E)/60%N2 mixtures at 0.3 MPa is 0.67-0.89 times that of SF6/N2 mixtures under the same conditions,which has great application prospect.
文摘The mitigation of the CO inhibition effect in palladium membranes is necessary due to its significance in the efficiency of membrane reactors and hydrogen production systems. In this work, the hydrogen separation performance of a Pd and Pd/Ag membrane both of thickness 2 μm is investigated using a mixed gas with composition (H2 = 50%, CO = 28%, CO2 = 10%, CH4 = 8%, N2 = 4%) at temperature 623 - 873 K and pressure (0.05 - 0.4 bar) was investigated. The component gases CO and CO2 were observed to inhibit hydrogen permeation through the membrane and lead to deviations from Sievert’s law for n values 0.55 and 0.62 for the Pd membrane and unity for the Pd/Ag membrane. For the Pd/Ag membrane, the concentration of CO in the permeate stream was reduced as a result of the addition of Ag. The effect of the component gases to hydrogen permeation was observed to be lower for the Pd/Ag membrane. Annealing the membrane in hydrogen at high temperature decreased the inhibition effect and enhanced hydrogen permeation through the membrane.
