Дослідження теплоакумулювальних властивостей цеолітів після мікрохвильової регенерації

The paper studies the kinetics of dehydration of a dense layer of zeolites 13X and 4A, which are used for heat storage systems based on thermochemical adsorption and desorption processes. The results of an analytical review of the literature data are presented, on the basis of which information was obtained about the efficiency of thermochemical heat storage by zeolites due to the high density of energy storage, as well as the possibility of long-term storage without energy loss. It was determined that the microwave dehydration method is rational for the regeneration of zeolites. A diagram of an experimental setup for conducting microwave drying studies and a methodology for conducting experiments are presented. The results of experiments on the dehydration of a dense layer of zeolites 13X and 4A under microwave heating conditions at a magnetron output power of 800 W, the initial loading mass is 0.1 kg. The curves of changes in moisture content and temperature of zeolites during microwave drying are shown. An analysis of the nature of changes in moisture content and temperature for the studied zeolites is presented. The strength properties of zeolites are assessed based on the results of determining the quality of grains after seven sorption-desorption cycles. The results of the assessment of the heat storage capacity of zeolites after dehydration in a microwave field are presented. It was taken into account that the heat of adsorption released after adding water to the zeolite layer was used to heat the water, the experimental cell, the zeolite layer, and the evaporation of moisture. The specific heat of adsorption of the studied zeolites varies within 155.5 kJ/kg - 216.4 kJ/kg, while the error did not exceed 15.7%. It was found that zeolite 13X is preferable for thermochemical heat storage systems in terms of strength characteristics and heat storage capacity, but the final choice is determined by the specific conditions of use.