Ammonia-based chemisorption heat pumps for cold-climate heating applications: A comprehensive review. (October 2020)

• Record Type: Journal Article
• Authors: Yang, Zhiyao; Qu, Ming; Gluesenkamp, Kyle R.
• Is Part Of: Applied thermal engineering. Volume 179(2020)
• Publication Date: 2020-10
• Subjects: Chemisorption -- Ammonia -- Heat pump -- Adsorption -- Cold climate -- Ammoniated salts; AC activated carbon -- ACF activated carbon fiber -- C/E condenser/evaporator -- CF carbon fiber -- CNT carbon nanotube -- COP coefficient of performance -- CSHP chemisorption heat pump -- DRES double-effect resorption -- DSCE double-effect separate condenser-evaporator -- EG expanded graphite -- ENG expanded natural graphite -- ENG-TSA expanded natural graphite treated with sulfuric acid -- EVM expanded vermiculite -- GFIC graphite fiber intercalation -- HTF heat transfer fluid -- HTS high-temperature salt -- HVAC heating, ventilation, and air conditioning -- ICF impregnated carbon fiber -- LT low temperature -- LTS low-temperature salt -- MT medium temperature -- MTS medium-temperature salt -- MWCNT multiwall carbon nanotube -- SCCE single-effect combined condenser-evaporator -- SCP specific cooling power -- SEM scanning electron microscopy -- SHP specific heating power -- SRES single-effect resorption -- SSCE single-effect separate condenser and evaporator; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2020.115674
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: New Clapeyron diagram compares 66 chemisorption working pairs. Innovative developments are reviewed for materials, components, and system designs. Research priorities are matching salts to applications and reducing thermal mass. Hysteresis and reaction heat of sorbent salts significantly affect performance. Abstract: This article reviews the state of the art of chemisorption heat pumps that use ammonia as the refrigerant for cold-climate heating applications. In such a system, ammonia vapor is adsorbed by the solid salt through reversible chemisorption reactions, and the thermal effect of the reaction and ammonia phase change is used to extract heat from a cold environment and supply heat to a warm environment. With the high latent heat and low boiling point of ammonia as a low-temperature refrigerant and the high sorption capacity of ammonia-based chemisorption reactions, chemisorption heat pumps have the potential to produce high-efficiency heating, particularly for cold climates. This review first briefly introduces the basics of ammonia-based chemisorption heat pump systems. Then, the latest development of sorbent materials, including ammoniate salts and heat-conductive porous matrix materials, are summarized with the focus on low-temperature heating conditions. The design of system components, as well as cycle configurations, in the literature are summarized. This review concludes with highlights of recent developments on these topics and suggestions of areas for further research.