Determination of the adsorption characteristics of different refrigerants on different adsorbents for adsorption heat pump applications


Thesis Type: Doctorate

Institution Of The Thesis: Uludağ Üniversitesi, Turkey

Approval Date: 2017

Thesis Language: Turkish

Student: ERSAN GÖNÜL

Supervisor: MUHSİN KILIÇ

Abstract:

The development and use of renewable energy has experienced rapid growth over the past few years. In the next 20–30 years all sustainable energy systems will have to be based on the rational use of traditional resources and greater use of renewable energy. Adsorption heat pumps can operate easily with all kinds of heat energy and devices with less electrical power needs. Adsorption heat pumps has become attractive devices which can provide direct cooling using waste heat sources, solar energy, geothermal energy or any heat source. Studies continue to improve performance and to increase usage for adsorption heat pumps. The successful operation of these systems mostly depends on the correct choice of the adsorbent-adsorbate working pair. In this study, firstly, an adsorption experimental set-up was designed and constructed to obtain the isotherms of the working pair. R134a and then R404a is chosen as adsorbate which are commonly used and which are hidrofluorocarbon (HFC) of the refrigerating fluid. Activated carbon, activated alumina, zeolite, polimer and various silica gel are used as adsorbent. Adsorption parameters were evaluated from the isotherms using the Dubinin-Astakhov (DA) equation. The concentration dependence of the isosteric enthalpies of adsorption is extracted from the data. Further, the enthalpy of adsorption data were extracted, and correlations are provided for the different specimens investigated. These data are essential in designing a thermally driven adsorption chiller based on the assorted pair.