Chemical Engineering
Rozita Kaviani; Amir Arezi
Abstract
The ability of pinch technology to provide a general approach to process design and analysis, but it is incapable of analyzing systems that include power in addition to heat. On the other hand, exergy analysis The main limitation of exergy analysis is the lack of a comprehensive system design method. ...
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The ability of pinch technology to provide a general approach to process design and analysis, but it is incapable of analyzing systems that include power in addition to heat. On the other hand, exergy analysis The main limitation of exergy analysis is the lack of a comprehensive system design method. The combined analysis of punch and exergy, obtained from combining the two mentioned methods, uses both methods to remove both methods’ limitations. In this article, by introducing the Ahvaz Ramin power plant as the studied power plant, an attempt has been made to identify and examine effective improvements using the CPEA(Combined pinch and Exergy Analysis) method. Three proposed correction scenarios have been used to optimize the power plant: 1- Approaching the pins, 2- Increasing the steam in the boiler 3- Decreasing the condenser pressure. The results show that it is possible to increase the studied power plant’s efficiency by about 1.7% by using this method. The fuel consumption of 1569 cubic meters per hour reduces emissions by about 1.7 percent (equivalent to 20 tons per hour). Therefore, the production of pollutants is significantly reduced. Thermoflow software (Steam Pro) simulated the power plant and Aspen Pinch software for CPEA analysis.
Chemistry
Rozita Kaviani
Abstract
The present research specializes in the second law analysis to characterize the balances of properties and efficiencies of processes occurring in nuclear reactions. The conceptual schema is underpinned by the paradigm of microscopic few-particle systems and the inter-particle kinetic energy and binding ...
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The present research specializes in the second law analysis to characterize the balances of properties and efficiencies of processes occurring in nuclear reactions. The conceptual schema is underpinned by the paradigm of microscopic few-particle systems and the inter-particle kinetic energy and binding potential energy determined by interactions among atomic nuclei and subatomic particles in non-equilibrium states along with irreversible phenomena. The proposed thermodynamic entropy calculation is based on energy and exergy, both being measurable properties used to directly derive entropy variations determined by elemental fission and fusion nuclear reactions in operating industrial plants. The interest in developing second law analysis founded on exergy method applied to fission and fusion nuclear reactions can be found in: i) the observation of physical phenomena and nuclear processes through a thermodynamic standpoint; ii) the need of adopting a more extended approach to nuclear reactors design in the perspective of the optimization and confrontation of different types of technologies and plant configurations
Chemical Engineering
Amin Ahmadpour; Rozita Kaviani
Abstract
Today, the recovery of acetone as an expensive and widely used solvent in the production units of methyl methacrylate, bisphenol A, MTBA, plastics and synthetic fibers is very important. One of the most common recovery methods is the absorption process (solvent separation), which is sometimes used in ...
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Today, the recovery of acetone as an expensive and widely used solvent in the production units of methyl methacrylate, bisphenol A, MTBA, plastics and synthetic fibers is very important. One of the most common recovery methods is the absorption process (solvent separation), which is sometimes used in combination with surface absorption or membrane separation due to its cheapness and availability of knowledge. In this research, it was simulated with Aspen Plus V 7.2 software and the experimental rules of absorption and distillation columns, and with the Levi-Benn model to recover 99.5% of acetone from its mixture with air (10.3-687Mol/hour), the optimal conditions for the absorption tower, 20 equilibrium stages were obtained at atmospheric pressure with effluent and return gas from the separation section. In this situation, the molar ratio of the reflux of the distillation tower is 20.9 with the minimum energy consumption in the partial condenser at the rate of 2.3 Kw and 20 equilibrium stages.
Chemical Engineering
Rozita Kaviani; Ahmad Omidvar; Amir Arezi
Abstract
In recent years, cogeneration systems have been considered to increase the efficiency and optimal use of energy sources for the production of electrical energy and heat energy. Electricity and heat energy cogeneration systems can achieve up to 70% efficiency, and at the realistic and subsidized rates ...
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In recent years, cogeneration systems have been considered to increase the efficiency and optimal use of energy sources for the production of electrical energy and heat energy. Electricity and heat energy cogeneration systems can achieve up to 70% efficiency, and at the realistic and subsidized rates of energy carriers, the beneficiaries of these systems supply the demand and supply sectors. In this study, the optimal working point of a system consisting of several independent units, capable of trading electricity, based on the consumption of various fuels, and utilization of storage tank was determined using genetic algorithm, and modeling accuracy were compared. Other references have also been made. The simulation results show that in the temperate seasons and summer, the cogeneration system meets all electrical and thermal requirements during the 22-23 hours due to the high electricity grid rate and at the end of 24 hours, the total cogeneration cost For almost all seasons 50% less than the conventional production system. It has also been shown that the use of absorption chillers has improved the ratio of electrical and heat loads, and the efficiency of the cogeneration system has increased compared to the previous state, and the heat energy loss has also decreased.
