INCREASING ENERGY EFFICIENCY OF THERMAL POWER PLANTS BASED ON EXERGIC ANALYSIS AND OPTIMIZATION OF HEAT RECOVERY SYSTEMS
Abstract and keywords
Abstract:
The study objective is to analyze existing heat recovery systems (HRS) of power plants, demonstrate the possibilities of exergic method for their evaluation and optimization, as well as feasibility study for their implementation. The main task is to apply a thermodynamic approach based on the second law (exergic analysis) to identify and minimize irreversible energy efficiency losses in HRS per day, which allows to move from a quantitative to a qualitative assessment of their effectiveness. Methods and solutions include exergic method, mathematical modeling, and system analysis. Constructive and technological solutions are considered: modular HRS for internal combustion engines with recovery boilers, combined steam-to-gas cycle (SGC) and cascade systems with an organic Rankine cycle (ORC). The novelty of the work is in the integrated application of exergic approach for comparative analysis and optimization of different types of HRS, as well as in the generalization of data on commercially available equipment for thermodynamic and feasibility studies. Main results and conclusions: Exergic analysis made it possible to localize the key sources of irreversibility – the combustion chamber and the zones of high-temperature heat exchange. It is shown that the HRS introduction especially in combined cycles increases the total efficiency of installations to 80-90% with a payback period of 2-5 years. Optimization according to exergic criteria leads to lower fuel costs, emissions and an increase in the sustainability index. Cascade heat utilization, ORC integration, and control system intellectualization are recognized as promising areas.

Keywords:
utilization, heat, energy efficiency, analysis, energy, installation, combined cycle, efficiency, optimization
References

1. Avaryaskin KN, Molchanov YaO. Exergic analysis and optimization of heat exchangers for heat recovery systems of gas-piston power plants. Civil Aviation High Technologies. 2020;23(2):154-165.

2. Bespalov VN, Golubev AYu. Combined energy production: cogeneration and trigeneration based on internal combustion engines. Moscow: MEI Publishing House; 2018.

3. Mikheev AS, Rumyantsev AA. Exergic and economical optimization of a steam-gas plant with afterburning of fuel. Teploenergetika (Thermal Engineering). 2021;5:45-53.

4. Petin AN, Sokolov EYa. Feasibility study of introducting heat recovery systems at diesel power plants. // Energysaving and Watertreatment. 2019;4(126):34-39.

5. Sychev VV. Complex thermodynamic systems. Exergetic method of analysis and optimization. 2nd ed. Moscow: MEI Publishing House; 2017.

6. Bejan A, Tsatsaronis G, Moran M. Thermal design and optimization. New York: John Wiley and Sons; 1996.

7. Dincer I, Rosen MA. Exergy: energy, environment and sustainable development. 3rd ed. Oxford: Elsevier; 2021.

8. Karellas S, Braimakis K. Energy–exergy analysis and economic investigation of a cogeneration and trigeneration ORC–VCC hybrid system utilizing biomass fuel and solar power. Energy Conversion and Management. 2016;107:103-113.

9. Song J, Gu C-W, Ren X. Parametric design and off-design analysis of organic Rankine cycle (ORC) system. Energy Conversion and Management. 2016;112:157-165.

10. Wang J, Yan Z, Zhao P, Dai Y. Exergoeconomic analysis and optimization of a combined cooling, heating and power system based on organic Rankine and vapor compression cycles. Energy. 2017;141:150-164.

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