Development of Operating Fluids for Chemical Heat Pump Driven by Unused Heat

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K04302
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 19020:Thermal engineering-related
• Research Institution: Chiba University
• Principal Investigator: OGURA HIRONAO 千葉大学, 大学院工学研究院, 教授 (40253554)
• Co-Investigator(Kenkyū-buntansha): 廣瀬 裕二 千葉大学, 大学院工学研究院, 助教 (60400991)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ケミカルヒートポンプ / 冷熱生成 / 蒸発平衡 / 蒸発速度 / 熱交換媒体 / 潜熱蓄熱媒体 / 太陽集熱

Outline of Final Research Achievements

In this study, we performed evaporation/condensation solution development for cold-heat generation less than -20 degrees Celsius and the development of the heat exchange medium (HEM) that heat promotion of recovery was possible in 100 degrees Celsius or more toward practical use of chemical heat pump (CHP).
By the development of evaporation/condensation solution, the freezing point was lowered while maintaining the steam pressure by putting polyethylene glycol in the ethylene glycol water solution. Furthermore, the evaporation rate was studied and showed to be few possibility with evaporation determining-rate in 228 K. In the development of HEM, erythritol which has a high latent heat amount and high temperature melting point was mixed to oil with oleyl alcohol. The new HEM made it possible to increase the transportable thermal energy amount and the recovery heat of CHP unit with the lowered increase of a pressure energy loss and the heat loss.

Free Research Field

Thermal Energy Engineering

Academic Significance and Societal Importance of the Research Achievements

ケミカルヒートポンプは、再生可能エネルギーである太陽エネルギーや各種工場廃熱等の未利用エネルギーを熱回収、熱交換、化学蓄・放熱さらに必要に応じて熱輸送を行うことにより、化石燃料や電力やガス等の他のエネルギーをもほとんど用いない熱リサイクル利用可能な独立型高効率未利用熱駆動冷凍・冷暖房・給湯システムの構築が可能である。各種ケミカルヒートポンプの反応材性能はほぼ実用化レベルに達していると考えているが、未だ高効率に駆動可能な普及実用化段階に至っていない要因の一つである作動溶液の課題を本研究で解決に近づける大きな学術的社会的意義があったと考える。