چكيده به لاتين
In this thesis a combined power and cooling cogeneration system has been investigated. Since heat loss from power generators is inevitable. In this study, a novel configuration is introduced to benefit from this waste heat. The components of the proposed system are: adsorption cooling cycle, organic Rankine cycle and a hot water storage tank, which receive their required energy from the waste heat of the gas engine to produce cooling and electricity. Due to their compatibility with the environment, utilization of low temperature heat sources and simplicity, adsorption cooling systems are an attractive alternative to vapor-compression and absorption cooling systems in recovery of waste heat sources. In this research, by transient modeling of an adsorption system, the performance and limitations of the system have been investigated. In addition, to fix the periodicity problem of this cooling cycle, the use of a hot water tank is suggested and studied. On the other hand, since the heat loss from the gas engine occurs in two temperature ranges, high in the exhaust gas and low in the engine cooling water cycle. Even after low-temperature waste heat recovery, there is still potential for recovering high temperature waste energy. Therefore, organic Rankin cycle has been studied to make maximum use of the waste heat of the gas engine. In this thesis, technical and economic modeling of all the mentioned components as well as the integrated system has been done. to identify the factors affecting the performance of the components and the integrated system. Calculations have been performed for 7 gas engines with different nominal powers in the range of 300 to 1100 kW. The results show that the maximum overall efficiency of the cogeneration system is 55% with an energy saving rate of 43% and 17.21% increase in efficiency for an engine with a nominal power of 432 kW. Also, the highest amount of relative annual benefit is 145933$ which is gained by using 1042 kW gas engine. In this case, the payback period for adsorption-ORC equipment added to the existing gas engine is about 4.39 years. Due to the fact that some economic and technical parameters such as interest rates, electricity prices and the period of time in a year which cooling is required, are variable and depend on the system location. The sensitivity analysis of the annual relative benefit function to these parameters has been performed. The results show that the price of electricity and interest rate only in a limited range for different engines will lead to economic justification for the system.
