| Indoor air humidity and pollutant concentration control are important measures to ensure personnel comfort and health.Unreasonable air humidity can reduce the thermal comfort of indoor personnel,thereby affecting their work efficiency and quality of life.The concentration of indoor air pollutants not only affects the comfort level of personnel,but also directly affects their health level.As an important component of indoor air pollutants,volatile organic compounds(VOCs)have been proven to have a direct impact on personnel’s eyes,respiratory tract,and skin,and some VOCs even have carcinogenicity.After investigation,among the existing indoor air humidity control and VOCs elimination technologies,adsorption technology has received widespread attention due to its ability to achieve dual adsorption of water vapor and VOCs,and the absence of by-products during the adsorption process.However,solid adsorption dehumidification technology also faces the challenge of high regeneration temperatures.To utilize low-grade energy for regeneration,restructuring the solid adsorption dehumidification and purification air conditioning system is an important direction for optimization.On the other hand,the selection of adsorption materials with high adsorption capacity and low regeneration temperature for water vapor and VOCs is the core of improving the performance of solid dehumidification and purification air conditioning systems.Based on the above background,this paper proposes a solid adsorption dehumidification and purification air conditioning system with heat pump condensing heat regeneration,and analyzes its performance and applicability;on this basis,the adsorption materials applicable to the solid adsorption dehumidification and purification air conditioning system are explored in order to further optimize the solid dehumidification and purification air conditioning system.The details of the study are as follows:Firstly,a solid adsorption dehumidification purification air-conditioning system based on heat pump condensation heat regeneration was proposed,and its air heat and humidity treatment process and energy efficiency theory of computation models were established.The air treatment process and energy efficiency of typical cities in different climatic regions in China and different working modes were simulated.The results showed that when the treated air was in the "fresh air+return air" mode,and the system assumed the indoor full heat load mode,the operation effect was the best,In typical cities in severe cold regions,east and midwest of cold regions there are 10.00%,10.61%,and 10.91% improvements in the energy efficiency ratio of air-cooled single cooling air duct air conditioning units compared to the provisions of the“General Specification for Building Energy Conservation and Renewable Energy Utilization”.In typical cities in hot summer and cold winter regions and hot summer and warm winter regions,or when the air is treated with fresh air and the system only bears the indoor dehumidification load mode,there are still situations where energy efficiency is low or even the condensation heat of the heat pump is insufficient to meet the demand for regenerative heat.The system operates under different climatic conditions and operating modes,with significant differences in applicability and energy-saving effects.On the other hand,the proposed solid adsorption dehumidification purification air conditioning system has a larger volume compared to conventional condensation dehumidification systems.To further address the above issues,this article explores porous materials suitable for solid adsorption dehumidification and purification air conditioning systems.Based on the high specific surface area and adjustable pore size characteristics exhibited by the metal organic skeleton material MIL-101(Cr)in literature research.This article first conducted a comparative analysis of the dehumidification performance between the metal organic skeleton material MIL-101(Cr)and traditional materials such as silica gel and activated carbon.When the relative humidity in line with the solid adsorption purification air conditioning conditions studied in this article is 50% to 70%,the adsorption capacity of MIL-101(Cr)on water vapor is 3.2-6.9 times that of silica gel and activated carbon.At the same time,it exhibits superior regeneration performance at 45℃ and RH30% operating conditions,with the potential for low-temperature regeneration.Regarding the air purification performance of MIL-101(Cr),this article tested the performance of MIL-101(Cr)in adsorbing typical indoor VOC toluene using the breakthrough curve method.The results showed that MIL-101(Cr)had an adsorption capacity of 5.8-7.5 times that of silica gel at 0.15 mg/m3 to 0.2 mg/m3(the indoor toluene concentration limit specified in the General Specification for Building Environments).The adsorption capacity of toluene increases with the increase of toluene concentration,with a temperature of25℃,a gas flow rate of 150 m L/min,and a toluene concentration of 700 ppb reaching 2515mg/g;Its saturated adsorption capacity for toluene decreases with increasing temperature,and the decrease is significant.The saturated adsorption capacity at 40℃ is only 25.8% of that at18℃,confirming the possibility of using relatively low temperature thermal regeneration.In summary,this article proposes a solid adsorption dehumidification and purification air conditioning system based on heat pump condensation heat regeneration.In typical cities in severe cold regions,eastern and central western regions of cold regions,the air is treated in a "fresh air+return air" mode,and the indoor total heat load mode of the system has good energysaving effects.To further optimize its performance in other climate zones and working modes,the air dehumidification and purification performance of metal organic skeleton material MIL-101(Cr)was explored.Its air dehumidification,purification,and low-temperature regeneration have significantly improved compared to traditional materials.The research methods and results of this article are expected to provide theoretical and experimental basis for the development of new solid adsorption purification air conditioning systems. |
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