Waste Heat Recovery Analysis: An Overview of Reversed Heat Pump Systems
[1]
Kevin Nnanye Nwaigwe, Department of Mechanical Engineering, University of Botswana, Gaborone, Botswana.
Heat recovery systems are usually assembled by combining a number of systems towards achieving the desired objective. To achieve waste heat recovery, heat pumps incorporate appropriate changeover or reversing valves to achieve cooling, thereby recovering the expected end product of heat. This paper presents an overview of reversed heat pump systems used for waste heat recovery. The review identifies the core components of reversed heat engines as compressor, condenser, expansion device evaporator and drying chamber. Also, the study identified the four basic types of heat pumps and they include air-to-air heat pumps, water-to-air heat pumps, water-to-water heat pumps and ground source heat pumps. Furthermore, the study identified the available waste heat recovery equipment and their classification. The common classification include steam generators, recuperators, shell and tube heat exchangers, fin tube heat exchangers, heat pipes and run-around-coils. Typical schematics of these systems, showing their component parts, are also presented. Finally, a study of the benefits of waste heat recovery systems is presented and the work identifies both direct and indirect benefits. Direct benefits include improved efficiency of a system while indirect benefits include reduction in pollution, reduction in equipment sizes, and reduction in auxiliary energy consumption. This findings presents a thorough knowledge base on reversed heat pumps for waste heat recovery.
Heat Engines, Waste Heat, Recovery, Pumps; Systems
[1]
Ai, S., Wang, B., Li, X., & Shi, W. (2019). Comparison of mechanical vapor recompression technology for solution regeneration in heat-source tower heat pumps. Building Services Engineering Research & Technology, 40(3), 360-378. doi: 10.1177/0143624418817461.
[2]
Farshi, L. G. l. g. t. a. i., & Khalili, S. (2019). Thermoeconomic analysis of a new ejector boosted hybrid heat pump (EBHP) and comparison with three conventional types of heat pumps. Energy, 170, 619-635. doi: 10.1016/j.energy. 2018.12.155.
[3]
Frate, G. F., Ferrari, L., & Desideri, U. (2019). Analysis of suitability ranges of high temperature heat pump working fluids. Applied Thermal Engineering, 150, 628-640. doi: 10.1016/j.applthermaleng. 2019.01.034.
[4]
Liu, L. c. c., Wang, M., & Chen, Y. (2019). A practical research on capillaries used as a front-end heat exchanger of seawater-source heat pump. Energy, 171, 170-179. doi: 10.1016/j.energy. 2019.01.012.
[5]
Lalovic, M., Radovic, Z. and Jaukovic, N (2005), Characteristics of Heat Flow in Recuperative Heat Exchangers, A Paper Presented At The VI Symposium ‘Contemporary Technologies And Economic Development, Leskovac, October 21-22, 2005. Hem. Ind. 59 (9-10) pp. 270-274.
[6]
Mozzo, L (2007), Energy Auditing, Handbook of Energy Audit and Environmental Management, Edited by J.P. Abbi and Shashak Jain, New Delhi.
[7]
Siemens Switzerland Limited. (2010), Heat Recovery in the Refrigeration Cycle, An Extract of Training Module by Siemens Ltd. Building Technologies Unit, www.siemens. com/buildingtechnologies.
[8]
Wang, S. K. (2001), Handbook of Air conditioning and Refrigeration, Second Edition, McGraw-Hill, P. 12. 3.
[9]
Energy Solutions Centre, FoodPro (2007), Flue Gas Heat Recovery, Version 1.0. www.thermalenergy.com.
[10]
Eastop, T. D. and McConkey, A. (1993), Applied Thermodynamics, Fifth Edition, ELBS Britain, pp 485-528.
[11]
HVAC HESS (2013) Heating, Ventilation & Air-Conditioning High Efficiency Systems Strategy.
[12]
Ahmed, R, and Ahmed, D. (2009), Thermal Hydraulic Modeling of the Steady-state Operating Conditions of a Fire-tube Boiler, Nuclear Technology & Radiation Protection Scientific paper, Biblid: 1451-3994, 24 (1), pp 29-37.
[13]
Ting, C. and Chen, C. (2011), Experimental Analysis Of Heat Transfer Behavior Inside Heat Pipe Integrated With Cooling Plates, Journal of Engineering Science, 3, pp 959-964, Published Online September 2011 (http://www.SciRP.org/journal/eng).
[14]
Salehi, S., Yari, M., & Rosen, M. A. (2019). Exergoeconomic comparison of solar-assisted absorption heat pumps, solar heaters and gas boiler systems for district heating in Sarein Town, Iran. Applied Thermal Engineering, 153, 409-425. doi: 10.1016/j.applthermaleng. 2019.03.022.
