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Asymmetric Thermoelectrochemical Cell for Harvesting Low-grade Heat under Isothermal Operation
Published on: February 5, 2020
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Configuration Selection of the Multi-Loop Organic Rankine Cycle for Recovering Energy from a Single Source.
1The Institute of Power Drive and Control, Department of Electronic Engineering, Shanghai Maritime University, 1550 Haigang Ave., Shanghai 201306, China.
Entropy (Basel, Switzerland)
|November 27, 2021
Summary
The optimal Multi-Loop Organic Rankine Cycle (ORC) configuration for single waste heat sources is a series dual-loop system using cyclohexane. This design maximizes exergy efficiency and minimizes electricity costs.
Area of Science:
- Thermodynamics
- Energy Recovery
- Waste Heat Utilization
Background:
- The Organic Rankine Cycle (ORC) is effective for single waste heat recovery.
- Multi-Loop ORC (MLORC) configurations offer potential for enhanced performance.
- Optimizing MLORC requires careful selection of configuration, loop number, and working fluids.
Purpose of the Study:
- To determine the optimal configuration, number of loops, and working fluids for Multi-Loop ORC (MLORC).
- To analyze thermodynamic and economic performance of different MLORC configurations.
- To identify the most suitable MLORC system for single waste heat source utilization.
Main Methods:
- Multi-objective optimization applied to series and parallel MLORC configurations.
- Analysis of thermodynamic performance (exergy efficiency) and economic performance (levelized cost of electricity).
- Evaluation of different working fluid groups and loop configurations (dual, triple, quadruple).
Main Results:
- Series MLORC configurations demonstrated higher exergy efficiency compared to parallel configurations.
- Optimal series dual-loop, triple-loop, and quadruple-loop ORC showed significant exergy efficiency gains over parallel designs (9.3%, 7.98%, 6.23% respectively).
- The series dual-loop configuration using cyclohexane was identified as the most suitable for single waste heat sources.
Conclusions:
- Dual-loop systems are optimal for recovering energy from a single heat source based on grey relational grade analysis.
- The series dual-loop ORC with cyclohexane achieved an exergy efficiency of 62.18% and a levelized cost of electricity of $0.1509/kWh.
- This study provides a framework for optimizing MLORC systems for efficient waste heat recovery.
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