scholarly journals Ecotechnical Analysis of Gas Turbines Heat Recycling Using Organic Rankine Cycle (ORC) in Gas Pressure Amplification Facilities

Author(s):  
Chang Li ◽  
Yuchao Huang

Since the output temperature of the turbine in gas amplification stations is very high, there is the potential of using the joint production of heat and electricity. Organic Rankine Cycle (ORC), for recovering the waste heat of gas turbines, is being used around the world as a reliable and economical technology. This cycle has technical, economic and performance advantages comparing to the classic Rankine cycle. ORC cycle simulation using ASPEN HYSYS software was such that the simplest ORC cycle works with a single fluid and has the least efficiency among more advanced and common processes, is chosen to apply the choices and the work conditions of the sample station in. Since the executer companies of ORC cycle don’t use the simple cycle because of its low efficiency, we have used the simple process only to start simulating the more complicated cycles. If we assume pentane fluid to be the fluid of the simple cycle, we can get the pure output power, efficiency and capital return per different environment temperatures, turbo compressor’s other output discharges and also its different temperature, in various temperatures and different discharges. If the number of facilities which are equipped with the heat recovery system increases, the cost of each megawatt of produced power will significantly decrease and capital return decreases to two years or even less. Using the ORC cycle to return the capital under seven years is also justifiable economically.

2018 ◽  
Vol 245 ◽  
pp. 04010 ◽  
Author(s):  
Aleksandr Sebelev ◽  
Aleksandr Kirillov ◽  
Gennadii Porshnev ◽  
Kirill Lapshin ◽  
Aleksandr Laskin

Organic Rankine Cycle (ORC) thermodynamic optimization is of critical importance while developing new plants. Optimization procedures may be imed at the highest efficiency as well as cost or sizing minimization. Optimization process is generally carried out for plant nominal rating. At the same time, part-load operation has to be carefully considered in case of waste heat recovery from flue gases coming from internal combustion engines or gas turbines. Gas mass flow and temperature variations are specific to this application, significantly influencing ORC plant performance. Secure prediction of part-load operation is of particular importance for assessment of plant power output, providing stability and safety and utilizing proper control strategy. In this paper design and off-design cycle simulation model is proposed. Off-design performance of the ORC cycle recovering waste heat from gas turbine unit installed at gas compressor station is considered. Major factors affecting system performance are outlined.


Author(s):  
Fabrizio Reale ◽  
Vincenzo Iannotta ◽  
Raffaele Tuccillo

The primary need of reducing pollutant and greenhouse gas emissions has led to new energy scenarios. The interest of research community is mainly focused on the development of energy systems based on renewable resources and energy storage systems and smart energy grids. In the latter case small scale energy systems can become of interest as nodes of distributed energy systems. In this context micro gas turbines (MGT) can play a key role thanks to their flexibility and a strategy to increase their overall efficiency is to integrate gas turbines with a bottoming cycle. In this paper the authors analyze the possibility to integrate a MGT with a super critical CO2 Brayton cycle turbine (sCO2 GT) as a bottoming cycle (BC). A 0D thermodynamic analysis is used to highlight opportunities and critical aspects also by a comparison with another integrated energy system in which the waste heat recovery (WHR) is obtained by the adoption of an organic Rankine cycle (ORC). While ORC is widely used in case of middle and low temperature of the heat source, s-CO2 BC is a new method in this field of application. One of the aim of the analysis is to verify if this choice can be comparable with ORC for this operative range, with a medium-low value of exhaust gases and very small power values. The studied MGT is a Turbec T100P.


2020 ◽  
Vol 8 (5) ◽  
pp. 351 ◽  
Author(s):  
ChunWee Ng ◽  
Ivan C. K. Tam ◽  
Dawei Wu

Recent regulatory developments in the global maritime industry have signalled an increased emphasis on the improvement of energy efficiency onboard ships. Among the various efficiency enhancement options, recovering waste heat using the organic Rankine cycle (ORC) has been studied and identified as a promising one in many earlier studies. In this paper, a marine application of ORC for waste heat recovery will be discussed by performing the first law thermodynamic analysis based on the operating profile and machinery design data of an offshore service vessel (OSV) and defining four standard cycle configurations that include simple, recuperated, dual heat source, and with intermediate heating. The use of five hydrocarbon working fluids that are suitable for shipboard usage comprising cyclopentane, n-heptane, n-octane, methanol and ethanol are examined. The economic analysis found that annual fuel saving between 5% and 9% is possible and estimated a specific installation cost of $5000–8000 USD/kW. Among the various options, the methanol ORC in a simple cycle configuration is found to have the shortest payback time relatively balancing between annual fuel saving and total module cost. Finally, the simple cycle ORC running on methanol is further examined using the second law entropy generation analysis and it is found that the heat exchangers in the system accounted for nearly 95% of the overall entropy generation rate and further work is recommended to reduce this in the future.


Author(s):  
R. K. Bhargava ◽  
M. Bianchi ◽  
L. Branchini ◽  
A. De Pascale ◽  
F. Melino ◽  
...  

This paper presents a study related with off-shore oil & gas production and processing facilities, where required energy, for electric power, mechanical power and process heat, is mostly produced using gas turbines, as the fuel source (natural gas) is available onsite. Since size and weight of all equipment on an offshore facility are critical, it becomes necessary for the facility engineering team to ensure that all equipment are sized and selected appropriately to obtain better return on the investment. Therefore, any approach which could help in utilizing energy resources effectively will influence the bottom-line of the project, namely reduced capital cost and/or increased return on investment. In this paper, one such approach of recovering power and thermal energy through the use of Organic Rankine Cycle system is discussed. A detailed thermo-economic analysis, conducted considering a system with four gas turbines operating, shows that power recovery equivalent to one topping gas turbine is achievable with a suitable working fluid. The presented thermo-economic analysis clearly shows that use of the Organic Rankine Cycle system for waste heat recovery is a technically viable and economically attractive solution for the offshore applications.


2014 ◽  
Vol 1070-1072 ◽  
pp. 1808-1811 ◽  
Author(s):  
Han Lv ◽  
Wei Ting Jiang ◽  
Qun Zhi Zhu

Organic Rankine cycle is an effective way to recover low-grade heat energy. In order to improve system performance, for low-temperature waste heat of 120°C and R245fa,R600a,R227ea organic working fluid, using Aspen Plus software conducted simulation by changing the evaporation temperature. Results from these analyses show that decreasing the evaporation temperature, increasing thermal and exergy efficiencies, evaporating pressure, at the same time reduce steam consumption rate.


Author(s):  
Carlo Carcasci ◽  
Riccardo Ferraro

In the last years, the accelerated consumption of fossil fuels has caused many serious environmental problems such as global warming, the depletion of the ozone layer and atmospheric pollution. Similarly, low-temperature waste heat which is discharged in several industrial processes, contributes to thermal pollution and damages the environment. Furthermore, many industrial applications use low enthalpy thermal sources, where the conventional systems for the conversion of thermal energy into electrical energy, based on a Rankine water cycle, work with difficulty. Thus, the Organic Rankine Cycle can be considered a promising process for the conversion of heat at low and medium temperature whenever the conventional water cycle causes problems. Using an organic working fluid instead of water, the ORC system works like the bottom cycle of a conventional steam power plant. This kind of cycle allows a high utilization of the available thermal source. Moreover, the choice of the working fluid is critical, because it should meet several environment standards and not only certain thermophysical properties. This paper illustrates the results for the simulations of an Organic Rankine Cycle based on a gas turbine with a diathermic oil circuit. The selected working fluid is toluene. The design is performed with a sensitivity analysis of the main process parameters, the organic Rankine cycle is optimized by varying the main pressure of the fluid at different temperatures of the oil circuit. The off-design is performed by varying the temperature of the air condenser.


Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1499 ◽  
Author(s):  
Dominika Matuszewska ◽  
Piotr Olczak

Power conversion systems based on the Organic Rankine Cycle (ORC) have been identified as a potential technology especially in converting low-grade renewable sources or waste heat. However, it is necessary to improve efficiency of ORC systems. This paper focuses on use of low geothermal resources (for temperature range of 80–128 °C and mass flow 100 kg/s) by using modified ORC. A modification of conventional binary power plant is conducted by combining gas turbines to increase quality of steam from a geothermal well. An analysis has been conducted for three different working fluids: R245fa, R1233zd(E) and R600. The paper discusses the impact of parameter changes not only on system efficiency but on other performance indicators. The results were compared with a conventional geothermal Organic Rankine Cycle (ORC). Increasing of geothermal steam quality by supplying exhaust gas from a gas turbine to the installation has a positive effect on the system efficiency and power. The highest efficiency of the modified ORC system has been obtained for R1233zd(E) as a working fluid and it reaches values from 12.21% to 19.20% (depending on the temperature of the geothermal brine). In comparison, an ORC system without gas turbine support reaches values from 9.43% to 17.54%.


2021 ◽  
Author(s):  
Fabrizio Reale ◽  
Raniero Sannino ◽  
Raffaele Tuccillo

Abstract Waste heat recovery (WHR) can represent a good solution to increase overall performance of energy systems, even more in case of small systems. The exhaust gas at the outlet of micro gas turbines (MGTs) has still a large amount of thermal energy that can be converted into mechanical energy, because of its satisfactory temperature levels, even though the typical MGT layouts perform a recuperated cycle. In recent studies, supercritical CO2 Brayton Cycle (sCO2 GT) turbines were studied as WHR systems whose thermal source was the exhausts from gas turbines. In particular, subject of this study is the 100 kW MGT Turbec T100. In this paper, the authors analyze innovative layouts, with comparison in terms of performance variations and cogenerative indices. The study was carried out through the adoption of a commercial software, Thermoflex, for the thermodynamic analysis of the layouts. The MGT model was validated in previous papers while the characteristic parameters of the bottoming sCO2 GT were taken from the literature. The combined cycle layouts include simple and recompression sCO2 bottoming cycles and different fuel energy sources like conventional natural gas and syngases derived by biomasses gasification. A further option of bottoming cycle was also considered, namely an organic Rankine cycle (ORC) system for the final conversion of waste heat from sCO2 cycle into additional mechanical energy. Finally, the proposed plants have been compared, and the improvement in terms of flexibility and operating range have been highlighted.


Author(s):  
Felix Reinker ◽  
Karsten Hasselmann ◽  
Stefan aus der Wiesche ◽  
Eugeny Y. Kenig

The organic Rankine cycle (ORC) offers great potential for waste heat recovery and use of low-temperature sources for power generation. However, the ORC thermal efficiency is limited by the relatively low-temperature level, and it is, therefore, of major importance to design ORC components with high efficiencies and minimized losses. The use of organic fluids creates new challenges for turbine design, due to dense gas behavior and the low speed of sound. The design and performance predictions for steam and gas turbines have been initially based on measurements and numerical simulations of flow through two-dimensional cascades of blades. In case of ORC turbines and related fluids, such an approach requires the use of a specially designed closed cascade wind tunnel. In this contribution the design and process engineering of a continuous running wind tunnel for organic vapors is presented. The wind tunnel can be operated with heavy weight organic working fluids within a broad range of pressure and temperature levels. For this reason, the use of classical design rules for atmospheric wind tunnels is limited. The thermodynamic cycle process in the closed wind tunnel is modeled, and simulated by means of a professional power plant analysis tool, including a database for the ORC fluid properties under consideration. The wind tunnel is designed as a pressure vessel system and this leads to significant challenges particular for the employed wide angle diffuser, settling chamber, and nozzle. Detailed computational fluid dynamics (CFD) was performed in order to optimize the important wind tunnel sections.


Author(s):  
Felix Reinker ◽  
Karsten Hasselmann ◽  
Stefan aus der Wiesche ◽  
Eugeny Y. Kenig

The Organic Rankine Cycle (ORC) offers great potential for waste heat recovery and use of low-temperature sources for power generation. However, the ORC thermal efficiency is limited by the relatively low temperature level, and it is, therefore, of major importance to design ORC components with high efficiencies and minimized losses. The use of organic fluids creates new challenges for turbine design, due to dense gas behavior and the low speed of sound. The design and performance predictions for steam and gas turbines have been initially based on measurements and numerical simulations of flow through two-dimensional cascades of blades. In case of ORC turbines and related fluids, such an approach requires the use of a specially designed closed cascade wind tunnel. In this contribution the design and process engineering of a continuous running wind tunnel for organic vapors is presented. The wind tunnel can be operated with heavy weight organic working fluids within a broad range of pressure and temperature levels. For this reason, the use of classical design rules for atmospheric wind tunnels is limited. The thermodynamic cycle process in the closed wind tunnel is modeled and simulated by means of a professional power plant analysis tool, including a database for the ORC fluid properties under consideration. The wind tunnel is designed as a pressure vessel system and this leads to significant challenges particular for the employed wide angle diffuser, settling chamber, and nozzle. Detailed computational fluid dynamics analyses (CFD) were performed in order to optimize the important wind tunnel sections.


Sign in / Sign up

Export Citation Format

Share Document