New Adsorption Cycle for Upgrading the Ambient Heat

Abstract

Adsorption (chemical) heat transformation (AHT) is a new energy conservation and environmentally friendly technology that allows efficient use of heat sources with low temperature potential. Recently, a new cycle, called “Heat from Cold” (or HeCol) has been proposed to upgrade the temperature potential of the ambient heat. In the HeCol cycle, a natural reservoir of water with a temperature above 0°C is used as a heat source, and ambient air at T = (–20)–(–50)°C as a heat sink. The cycle is designed to produce heat at a temperature of 30–50°C, which can be used for heating of dwellings. The aim of this work is to select the adsorbent for the HeCol cycle and to test the laboratory prototype with the selected adsorbent. The work consists of three parts: (a) formulation of requirements to adsorbent, specialized for the HeCol cycles under various conditions; (b) analysis of data on adsorption equilibrium of commercial activated carbons and selection among them the materials suitable for the new cycle; and c) study of the laboratory prototype HeCol with the chosen adsorbent to analyze the feasibility of the new cycle. The main findings of this study are (i) the experimental demonstration of the HeCol cycle feasibility and (ii) the achievement of the specific heat generation power 8 kW/kg, which is of practical interest.