| China is actively promoting a low-carbon economy and high energy-consuming enterprises are limited by national energy policy, so enterprises is implementing large-scale transformation to improve energy efficiency and to save the energy resources. According to statistics, heating and air-conditioning energy consumption is 12.5%~17.5% of the total energy, so lots of the energy-saving measures emerge. Heat and mass cycle energy recovery system is an excellent total heat recovery Equipment, which can achieve high efficiency of energy recovery and realize the function of air purification, sterilization, smell removal and so on. Because heat and mass cycle energy recovery system is a new energy-efficient technology, it is still in the initial research stage. Using desiccant/regeneration heat and mass transfer theory and cooling tower heat and mass transfer theory, this paper establish mathematical model of energy tower through the thermal analysis and solving differential equations. Using MATLAB software, the trend of temperature difference, moisture content difference and enthalpy difference along the energy tower and heat recovery efficiency under the condition of the different gas-liquid ratio, NTU, Le and solution concentration both have been analyzed.Solution selection and the choice of the concentration are essential for the effect of energy recovery, lithium chloride solution is wider application by technical analysis, so it is the refrigerant of the system operation. In the case of reference mathematical expression of the solution performance parameters and different air import and export state parameters, the solution concentration is obtained by technical analysis.Through the numerical analysis of energy recovery tower and energy release tower, it is acquired which temperature, moisture content and enthalpy changes of energy tower is similar to the countercurrent heat exchanger, so it can be rough calculated for projects using the logarithmic mean temperature difference (LMTD) and the heat and mass transfer coefficient is received at the same time. We know that this error is very small through comparative analysis.Heat and mass cycle energy recovery system of a tobacco factory in Hunan recover of heat in winter and pre-cooling of fresh air in summer. According to the state parameters of emissions in the tobacco factory and the requirements of the air addressed, because the relative humidity is very low, solution concentration is high and the energy tower doesn't conducive to exothermic. So do some of the changes, such as increase the coil and the use of water as the working fluid, Heat recovery efficiency of energy tower improved is still high, reaching 64%, but higher water consumption.Based on the results of numerical simulation and engineering practice, heat and mass cycle energy recovery system has been improved to help improve heat recovery efficiency and reasonable match with the other equipment as well as adaptation with local climate and environment, etc. |
PDF Full Text Request