The Optimum Preparation And Adsorption Performance Test Of Low-Temperature Composite Adsorbent

Demand for cold storage preservation is becoming higher because of the living standard of people improving, so our country’s cold storage capacity grow rapidly. The problems of evaporator frosting and the high energy consumption are serious. This reduces the efficiency of defrosting, increases the energy consumption of cold storage refrigeration system, and even destroys the structure of the evaporator itself. Meanwhile, defrost refrigerator will bring internal temperature fluctuations and increases the energy consumption too. Using solid adsorption desiccant technology can reduce the water vapor content into the evaporator, makes it dropped below the saturated vapor pressure of the temperature to fundamentally prevent evaporator frosting problem.Firstly this article analyzes and studies the composite adsorbent preparation method. Many oxides and salts can disperse spontaneously onto the surface of supports to form a monolayer or submonolayer and there is a maximum amount of scattered. Based on this theory to explore a reasonable method of composite adsorbent preparation to improve the dehumidification performance.According to the process of preparation of composite adsorbent, the paper select sodium bromide, lithium chloride,5A and 13X to prepare composite adsorbent. We study solution concentration, solvent and dipping time to obtain the best method of composite adsorbent preparation. Experimental results show that using the solvent of water and alcohol can effectively solve the problem of destroying the physical frame when using water as solvent. It can also solve low solution concentration when using alcohol as solvent. Solution concentration has little influence to the capacity unless the concentration is too low.The effect of roasting temperature and the solvent on the adsorption quantity also has carried on the related research. Composite adsorbent was roasted under 300℃ to 600℃,and then test the adsorptive property through the test system of adsorption performance. Through experiment, composite adsorbent prepared by sodium bromide and lithium chloride can reaches a maximum under 450℃ and 400℃.The effect of different solvent on the adsorption quantity is little has also been found.This paper researches the composite adsorbent preparation. Through the analyzing variable parameters, the best method of composite adsorbent preparation has been found. This has guiding significance for dehumidification of cold storage.