Use of multicomponent fluid for waste heat recovery using kalina cycle

Abstract

Heat recovery from moderate temperature heat source and convert into electricity is very difficult task. In order to make this task possible, we must go for some modern method, conventional method will not work in this case. In an industrial scale large amount of moderate temperature heat is simply wasted. To recover waste heat, researcher come-up with the idea of use of multicomponent fluid as working fluid, rather than conventional single fluid. Various thermodynamic cycle such as the “Organic Rankine cycle, Super critical Rankine cycle, Kalina cycle, Goswami cycle, and Trilateral flash cycle” have been proposed and studied for the conversion of low grade heat source into electricity. In this context we are trying to recover some waste heat coming out from the industry. Most of the heat is wasted around the boiler of the steam power plant, or around the exothermic reactor, or through the flue gases coming out from chimney or stack. Using Kalina cycle we perform heat recovery task quite easily. Kalina cycle uses Ammonia and Water as working fluid. Using Aspen plus simulation this task can be perform and a reliable result would be obtained. For this case it is proposed to use only the equipment available in the Aspen simulation engine. Heat recovery from flue gases coming out from chimney of any industry will be studied using Aspen plus. Composition of Ammonia and Water mixture will be varied from 0.5 to 0.9 mass fraction of Ammonia. Flow rate of hot gases is kept constant, assuming that there is constant burning of fuel in the boiler. Power generated in this process is listed in the table, at various input pressure to the turbine. Efficiency of the process is calculated and listed in a table.