In this case study, EXERGY analysis is applied to a mini two-shaft gas turbine which is located in Islamic Azad University Khomeini Shahr Branch`s Thermodynamics laboratory and a proposal presented to make EXERGY DESTRUCTION less using a Heat Recovery Water Heater (HRWH). Calculations were done for N2=20000 (rpm) constant and various N1 and after that for N1=60000 (rpm) constant and various N2. Results revealed that the highest EXERGY DESTRUCTION rate occurs in combustion chamber in all conditions and a huge part of EXERGY DESTRUCTION through the turbine exhaust. Increase in N1 leads to increases in all component EXERGY DESTRUCTION rates. On the other hand, power turbine is the only component which is affected by changes in N2 and the EXERGY DESTRUCTION rate increases with increase in N2. Moreover, EXERGY gained rate within HRWH increased with increase in N1 and is almost constant with changes in N2. In the same vein, exergetic efficiency of HRWH and EXERGY gained rate within HRWH are increased with decrease in water outlet temperature of HRWH.

Shorter cycle times, better product quality and less product outage can be possible with faster cooling. But mold cooling channels can only be made in linear directions and limited forms via classical manufacturing methods. Therefore, it limits that performance of mold cooling. Developed in recent years additive manufacturing technologies are capable of building complex geometries and monoblock 3D products. With this technology it is possible to produce metal molds with conformal cooling channels in different forms and capable of qualified cooling. In this study, conformal cooling channels were designed in order to achieve optimum cooling in monoblock permanent mold. In this study, CFD (Computational Fluid Dynamic) analyses are performed to steady stead conditions for designed conformal cooling channels and classical cooling channel mold. Pressure drops, cooling channel outlet temperatures and EXERGY DESTRUCTIONs are calculated depending on the flow velocity rate in channels. The numerical investigations of the cooling process have shown that approximately 5% higher cooling performance can be achieved with conformal cooling channels. However, the pressure drop in the conformal cooling is observed to be higher than classical cooling channel. In addition, EXERGY DESTRUCTION in the conformal cooling channel is approximately 12% greater than the classical cooling channel.

Cement plants are one of the massive energy consumers and greenhouse gas producers. The processes carried out in a cement factory have considerable energy losses, and mostly happen due to the exhausted gases and airflow for cooling the clinker. The energy consumption in a regular plant is 25% electrical and 75% thermal. The main goal of this work is to represent a thermal recycling system in cement plants to generate power from high-temperature exhaust gases from the preheater and cooler high-temperature air. A thermodynamic analysis is carried out by the EES software, and the EXERGY efficiency and EXERGY DESTRUCTION of each component of the system are obtained. Moreover, a parametric study on the suggested cycle is used, and the results obtained show that if the input temperature and pressure of turbines get closer to the critical point of the expanded working fluid in turbines, the rate of net output work increases, which leads to an increase in the EXERGY efficiency of the whole system. The increased network of the cycle is almost 20%, which would rise from 3497 kW to 4186 kW, and the EXERGY efficiency would rise from 38% to 45. 94%.

The purpose of this manyscript includes providing new analysis and optimization method in process systems which is achieved due to the strengths of the simultaneous analytical methods of energy-EXERGY for thermal and chemical systems. In this treatise, it has been tried to with doing a comprehensive research effort, a new method is proposed to target energy-EXERGY process systems with help of other techniques in order to be useful in analyzing and optimizing process systems. In addition, EXERGY, EXERGYeconomic and pinch methods have been introduced according to the need and importance of relevant analyzes. In the following, the developed method in the synchronous combination of Pinch-EXERGY called Bridge-EXERGY is presented at two different levels for analyzing the energy and EXERGY process systems simultaneously. The output of this developed bridge-EXERGY method is a new and correlated equation for the simultaneous analysis of energy and EXERGY, which it leads to creation of an EXERGY Transmission Curve (ETC) for thermal equipment and an energy EXERGY DESTRUCTION curve (EDL) and an energy---EXERGY cost DESTRUCTION curve (ECDL) for equipment including pressure and composition change. Hereafter using this method of combining and analyzing the equipment of the process system, by using the artificial intelligence method called differential evolution algorithm, the optimization and integration of the whole process system are done simultaneously. Finally, based on the developed energy-EXERGY analysis method, a new algorithm is introduced and evaluated for the design of optimal process systems. As a field study for investigating the bridge-EXERGY combination method and optimization algorithm, NGL production process has been briefly investigated and thoroughly analyzed and optimized. In the process of natural gas separation, using the bridge-EXERGY combination method and artificial intelligence method, the differential evolution algorithm, the operating cost is reduced about 44 % and the annual profit is increased to about 814400 ($/year).

EXERGY analysis emboldens in cases that all the inefficiencies and bottlenecks to improve energy systems are to be addressed. In this study, a novel vapor compression air dehumidifier integrated with an auxiliary heat exchanger in series arrangement with the main condenser in order to mitigate the reheat coil, and an extra mixing box to recover the ventilated air heat has been introduced. A comprehensive methodology for exergetic analysis of vapor compression heating ventilation and air conditioning systems has been presented. The quasi-dynamic component-by-component EXERGY analyses of both the conventional and novel air dehumidification systems have been conducted for a specific outside air fraction. Also, sensitivity analyses have been conducted on the EXERGY DESTRUCTION and efficiency as a function of outside air fraction. Results denote that for the outside air fraction of 53%, EXERGY DESTRUCTION of the novel air dehumidification system has decreases up to 32. 4% and EXERGY efficiency has ramped up by 53. 45%. Moreover, by rising the outside air fraction from none to 100%, EXERGY DESTRUCTION in the novel air dehumidification system has declined by 46% to 30. 5 %, and EXERGY efficiency has undergone a 106% to 40. 3 % increase compared with the conventional system depending on the outside.

The EXERGY analysis is a proper method for performance evaluation of industrial systems. A generic and detailed analysis of the GPCSs on the second gas pipeline of Iran is made by the means of EXERGY. The two main improvement measures of fuel pre-heating and steam injection technologies are presented for the current conventional stations. Steady state equations regarding the second law of thermodynamics and the chemical and physical EXERGY analysis are presented as well. The results indicate that the improved cycle is a more energy saving one, with an overall efficiency and net output power. The exegetic efficiency of every gas turbine of the improved station is increased by 31% in average and their EXERGY DESTRUCTION is decreased by 84%. The amount of total EXERGY saving for the case study would be 552 MW. A higher overall efficiency can be achieved by an increase in both the turbine inlet temperature (TIT) and steam mass flow (SMF).

One of the industries with high potential for energy saving is the petrochemical industry. Ethylene and propylene production plants (olefin plants) – as a part of the petrochemical industry – are very energy intensive. So, any try to improve their energy consumption efficiency could lead to a high amount of energy saving. Iran’ s petrochemical industry uses old technologies and components and due to sanctions, it couldn’ t be improved. The main idea of this paper is to improve the energy consumption of one of the biggest petrochemical plants in Iran. So, Marun olefin plant in Iran has been simulated as a case study and its different parts have been analyzed from EXERGY point of view, which shows the most energy intensive components so that we can focus on for improving the plant’ s energy consumption. The plant has been divided into three sections and simulated using Aspen HYSYS process simulation software. Then, it has been analyzed using EXERGY analysis. Results show that the hydrogenation and separation section consisting of many different components has the highest EXERGY DESTRUCTION rate and the highest potential for energy saving. Compression section and refrigeration system having compressors are the other parts highly destroying EXERGY respectively. The causes of EXERGY DESTRUCTION for each component has been analyzed and recommendations have been proposed as well.

The cement industry is one of the most energy and carbon-intensive industries. The energy and carbon reduction is an important issue in this industry. The present work considers the use of alternative fuels in the cement kilns. The amounts of excess air, the location of fuel and air entrance, as well as the amount of produced gas stacks, are the main design and operational variables in the kilns. Comparative assessments of alternative fuels (AF) are performed by the mass, energy, and EXERGY analysis of different regions in the kilns. The obtained results show that using alternative fuels reduces the amounts of excess air and the exit temperature becomes closer to the ambient temperature. The alternative fuels demonstrate lower energy and EXERGY loss inside the cement kiln by supplying the required energy for the clinker production. Their utilization in the current kiln reduces CO2 emissions. The results of the present work may be used for the optimal design and operation of cement kilns. This work provides an in-depth analysis of the material efficiency, main energy losses and the EXERGY DESTRUCTION of the process.

C3MR, MFC, and DMR processes in an integrated LNG-NGL-NRU structure are investigated using the conventional and advanced EXERGY and exergoeconomic analyses. The results of advanced EXERGY analysis reveal that in most of the equipment, the highest amount of irreversibility is occurred because of endogenous EXERGY DESTRUCTION. In C3MR process, compressor C5 with 9730 kW; in MFC process, compressor C1 with 6342 kW; and in DMR process, compressor C3 with 10008 kW; have the most amount of avoidable endogenous EXERGY DESTRUCTION in comparison with the other equipment. According to the advanced exergoeconomic analysis, the amount of endogenous part of EXERGY DESTRUCTION cost and investment cost is higher than the exogenous part for most of the equipment, representing that interactions among the equipment is not considerable. Compressors have the highest amount of avoidable endogenous investment cost in all of the processes. Furthermore, in C3MR process, HX2 heat exchanger with 1121 $/h; in MFC process, compressor C1 with 450 $/h; and in DMR process, HX3 heat exchanger with 3955 $/h; have the most amount of avoidable endogenous EXERGY DESTRUCTION cost. Based on total costs defined for the equipment, in C3MR process, HX2 heat exchanger with 1126 $/h should be modified. In MFC process, compressor C1 with 504. 7 $/h should be considered. In DMR process, HX3 heat exchanger with 3963 $/h should be improved its performance. Finally, sensitivity analysis as well as validation have been conducted, and three different strategies are used to reduce the cost of avoidable EXERGY DESTRUCTION of system equipment.

Advanced EXERGY analysis is a tool to split the EXERGY DESTRUCTION of the system to achieve a better perspective about the potentials of a system for improvements. In addition, the component interactions and their EXERGY DESTRUCTION dependency with the other equipment are investigated through the advanced EXERGY analysis. For this purpose, it divides the EXERGY DESTRUCTION calculated by conventional EXERGY analysis, into endogenous/exogenous and unavoidable/avoidable. It can be concluded that the endogenous part has the most portion of EXERGY DESTRUCTION in components. In other words, component interactions have minor effects on system irreversibility, except heat exchanger E-100, which is affected by the compressor’s position. Sensitivity analysis is carried out to study the effect of some system parameters on compressor consumption power and total EXERGY DESTRUCTION of the system. Results show that lowering the feed temperature and raising the feed pressure, decrease the compressor power, and higher pressure ratio decreases the total EXERGY DESTRUCTION. Optimization is also carried out to reduce the power consumption of the compressor and propylene cooler.