چكيده به لاتين
Waste heat recovery from industrial processes in the past decades has attracted much attention in the field of energy. In this dissertation, a new configuration of four cycles including gas and steam cycles as well as an organic Rankine cycle and a Brighton biogas cycle are introduced to recover energy from hot exhaust gas. Also, the carbon-amine adsorption system is used to separate and store carbon dioxide from hot exhaust gases. For this new system, energy, exergy, economic, economic exergy and environmental exergy evaluations have been performed. This dissertation simulates and optimizes a combined solar cycle consisting of a Brighton and solar collector and an organic Rankine and Brighton biogas cycle to generate power and absorb carbon to produce methane in a methane generating unit. In this cycle, with the help of a solar collector, the central receiver enters the absorbed solar heat into the cycle and the excess amount will enter the storage system. This storage system will contain molten salt and the cycle will work only with solar heat and bring the air temperature to the desired level. The operating fluid, supercritical carbon dioxide, will then enter the gas turbine after passing through the receiver. On the one hand, because the turbine exhaust gases have a relatively high temperature, and on the other hand, carbon dioxide must reach a low temperature, so during the operation, it first enters the boiler and then returns to the Brighton solar cycle. The boiler converts water into steam and enters the steam turbine and the steam Rankin cycle is formed. After adsorbing carbon, it enters the methane generating unit and combines with the hydrogen obtained by electrolysis of part of the steam released from the steam Rankin cycle to produce methane. Innovation of this project is the use of supercritical carbon dioxide instead of air in the Brighton solar cycle and the use of molten salt storage system to store heat and use it when the weather is cloudy or at night when there is no sun and also use a methane generator after the organic Rankin cycle which is with power generation. To analyze the different sections, their thermodynamic and economic models are expressed and to determine the results, EES and MATLAB software are used, which will optimize the exergy-economic cycle to reduce costs and increase exergy. In this research, intelligent algorithms for optimizing genetic algorithms have been used for optimization. The target functions are the set exergy efficiency and the cost of electricity generation. At the optimal point, the values of exergy efficiency are equal to 61.7% and the cost of electricity generation is 267 Tomans per kilowatt hour. The results show that adding organic steam cycles and rankins to the gas cycle increases energy efficiency and exergy to 71.8 and 73.7, respectively. However, the integration of the carbon capture unit with this system reduces the energy and exergy efficiency to 50.5% and 51.9%, respectively. The economic results for the proposed system show that the simple return on investment and return on investment are both 1.5 years. In addition, net present value and domestic rate of return were 3.13 × 09 $and $ 0.68, respectively. In addition, the carbon capture system unit can prevent and convert 627,000 tons of carbon dioxide into methane fuel annually.
