The Efficiency Analysis Of Cogeneration System Based On Al-H₂O Reaction And The Simulation Of The Reactor

Energy crisis and environmental problems are driving people to explore and utilize new energy. Aluminum is an element rich in resources and is an energy carrier with high energy density. People can get hydrogen and heat and solve the problem of the oxide film on aluminum restricting reaction by use high temperature melted aluminum and water to reaction. The efficiency of energy utilization can be improved if use reaction heat for cogeneration.In this paper, there cogeneration systems based on aluminum and water reaction are proposed, which includes reactor、turbine、exchanger、fuel cell and pump. Hydrogen and steam which are used in turbine to generate power are generated in reactor, the hydrogen after turbine will goes into fuel cell to generate power, the water after turbine and fuel cell will goes into reactor for recycle use by pump. The heat user can get heat from exhausted gas of turbine and chemical reaction in fuel cell. System utilization efficiency of the three systems are nearly70%. Some impact of key factors such as inlet temperature of turbine, fuel cell efficiency, inlet pressure of turbine on system utilization efficiency、electricity utilization efficiency、heat user utilization efficiency are studied by calculating multiple working conditions.The reactor is a key equipment in cogeneration system, so the reactor made by cooperation research institute is studied on its heat transfer performance. Combined with experiment result,the heat transfer model based on "three zones" is established.The software which can automatically divide zones according to the phase of cooling water is made to calculate heat transfer performace.Appropriate radius and height of the reaction zone are determined according to the experimental data. The temperature range of the material of spiral tube are checked by the relevant standard. Suggestion to the experiment about the is proposed from a safety point.The reaction process of Al-H2O is simulated. The reaction process model of the water drop in the melted aluminum is established and is turned into software which can chase the whole process of single drop that includes evaporation, reaction and up lifting. The existed time of the water drop in the melted aluminum and the whole hydrogen generating rate is simulated and are checked by experimental data. Some impact of key factors that are temperature of aluminum, the temperature of inlet water, water drop radius on the hydrogen generation of reactor are studied by calculating multiple working conditions.