Study On Performance And Energy Consumption Of Desiccant Wheel Dehumidification Air Conditioning System

Due to the rapid development of economy and living standard,people's requirement for the high indoor environment quality has led to an increase in energy consumption.In order to achieve the reduction of energy consumption and the improvement of indoor air quality,an independent temperature-humidity control air conditioning system combined solid desiccant wheel with air source heat pump is presented in this paper.The performance of silica gel desiccant wheel was studied by means of simulation and experiment.According to the results of the desiccant dehumidification and research results of liquid desiccant from other researchers,energy consumption and exergy efficiency of condensing and rotary and solution dehumidification are calculated;the cooling and heating required in dehumidification is provided by air source heat pump.Due to the energy consumption of desiccant wheel is too high,an independent temperature-humidity control air conditioning system combined desiccant wheel with air source heat pump was presented.The desiccant wheel was regenerated by the high temperature exhaust gas and condensing heat of the compressor to save energy.The desiccant wheel is used for air dehumidification and the air source heat pump supply high temperature cold water / low temperature hot water for radiant panel.The main parts of the air conditioning system combined desiccant wheel with air source heat pump were designed and calculated,and an experimental platform was set up in the enthalpy difference laboratory to carry out experimental study.The results show that the experiment and simulation results of the desiccant wheel are basically coincident.It can facilitate desiccant dehumidification by increasing the regeneration air temperature,reducing the moisture content of recycled air,reducing air inlet temperature.Reducing the moisture content of air inlet,decreasing regeneration air velocity and increasing the process air velocity reduce the amount of dehumidification.There exist the optimal speed and ratio of regeneration area at different operation condition.The Calculation results of the three kinds of dehumidification methods show that condensing dehumidification operates with the least energy consumption and the highest exergy efficiency.The desiccant wheel operates with the highest power consumption and least exergy efficiency.Taking the load characteristics of a residential building in Zhenjiang city as the research object,the running result of the air conditioning system combining the desiccant wheel with air source heat pump show that the cooling capacity of the system can reach 14.76 kW and the dehumidification capacity can reach 8.1g/kg under the design condition,which can undertake the entire sensible heat load and latent heat load in the room.The cooling COP of the system can reach 4.1,save 13.6% energy comparing with traditional air-conditioning system in summer and the heating COP of the system can reach 3.68,save 20% energy comparing with traditional air-conditioning system.