Experimental investigation on a MnCl2–CaCl2–NH3 thermal energy storage system

Thermal energy storage (TES) is regarded as one promising technology for renewable energy and waste heat recovery. Among TES technologies, sorption thermal energy storage (STES) has drawn burgeoning attention due to high energy storage density, long-term heat storage capability and flexible working modes. Originating from STES system, resorption thermal energy storage (RTES) system is established and investigated for recovering the heat in this paper. The system is mainly composed of three high temperature salt (HTS) unit beds; three low temperature salt (LTS) unit beds, valves and heat exchange pipes. Working pair of MnCl2–CaCl2–NH3 is selected for the RTES system. 4.8 kg and 3.9 kg MnCl2 and CaCl2 composite adsorbents are filled in the adsorption bed. Results indicate that the highest thermal storage density is about 1836 kJ/kg when the heat charging and discharging temperature is 155 °C and 55 °C, respectively. Volume density of heat storage ranges from 144 to 304 kWh/m3. The highest ratio of latent heat to sensible heat is about 1.145 when the discharging temperature is 55 °C. The energy efficiency decreases from 97% to 73% when the discharging temperature increases from 55 to 75 °C.

[1]  Ruzhu Wang,et al.  Progress in the development of solid–gas sorption refrigeration thermodynamic cycle driven by low-grade thermal energy , 2014 .

[2]  Ruzhu Wang,et al.  Integrated energy storage and energy upgrade, combined cooling and heating supply, and waste heat recovery with solid–gas thermochemical sorption heat transformer , 2014 .

[3]  Takao Kashiwagi,et al.  Solar/waste heat driven two-stage adsorption chiller: the prototype , 2001 .

[4]  Ruzhu Wang,et al.  Study on consolidated composite sorbents impregnated with LiCl for thermal energy storage , 2015 .

[5]  Ruzhu Wang,et al.  Adsorption cold storage system with zeolite–water working pair used for locomotive air conditioning , 2003 .

[6]  Tianshu Ge,et al.  The present and future of residential refrigeration, power generation and energy storage , 2013 .

[7]  C. Majorana,et al.  Thermal storage of sensible heat using concrete modules in solar power plants , 2014 .

[8]  Sebastian Lourdudoss,et al.  An energy storing absorption heat pump process , 1987 .

[9]  L. W. Wang,et al.  Sorption thermal storage for solar energy , 2013 .

[10]  Jeffrey D. Spitler,et al.  Review of development from GSHP to UTES in China and other countries , 2009 .

[11]  Zacharie Tamainot-Telto,et al.  Development of thermal conductive consolidated activated carbon for adsorption refrigeration , 2012 .

[12]  Ruzhu Wang,et al.  A target‐oriented solid‐gas thermochemical sorption heat transformer for integrated energy storage and energy upgrade , 2013 .

[13]  A. Mawire,et al.  Simulated performance of storage materials for pebble bed thermal energy storage (TES) systems , 2009 .

[14]  Zhihua Zhou,et al.  Hourly operation strategy of a CCHP system with GSHP and thermal energy storage (TES) under variable loads: A case study , 2015 .

[15]  R. Velraj,et al.  Experimental investigation on a combined sensible and latent heat storage system integrated with constant/varying (solar) heat sources , 2007 .

[16]  Ruzhu Wang,et al.  Resorption system for cold storage and long-distance refrigeration , 2012 .

[17]  Hoseong Lee,et al.  Experimental investigation of energy and exergy performance of short term adsorption heat storage for residential application , 2014 .

[18]  Lingai Luo,et al.  A review on long-term sorption solar energy storage , 2009 .

[19]  Lianyun Wang,et al.  Development and characterization of silica gel–LiCl composite sorbents for thermal energy storage , 2014 .

[20]  Luisa F. Cabeza,et al.  1 – Introduction to thermal energy storage (TES) systems , 2015 .