Optimization Design And Simulation Research On The Absorption Heat Transformer For Recovering The Low-temperature Waste Heat

The Absorption Heat Transformer is a kind of energy-saving equipments, which can recover effectively the low-temperature waste heat. Because there are usually lots of low-temperature waste heat discharged from the process of supplying heat in winter by the hot geothermal water, this paper proposes an energy-saving scheme using the AHT system to recovery the geothermal waste heat.Based on the thermodynamics principles, the LiBr-H2O AHT system is described mathematically by establishing the mass balance equation and the energy balance equation and utilizing the mathematical equation about the LiBr-H2O's thermal properties. The simulation program of the LiBr-H2O AHT system is complied and through using the simulation program, the change of the LiBr-H2O AHT system's performance on the main system parameters, the evaporating temperature, the condensing temperature, the absorbing temperature, the generating temperature and etc, is discussed. From the discussion, the system's performance can be improved by raising the absorbing temperature, lowering the condensing temperature or lowering the condensing temperature. The optimization designing of the LiBr-H2O AHT system is analyzed by using the variable tolerance method, one of the nonlinear programming methods. On the basis of the simulation program, the optimization program is complied. In accordance with the energy-saving scheme's characteristics, a new majorized function considering both the ratio of quality to price and the waste heat recovering effect, was proposed through analyzing the optimization results under the old majorized functions and a perfect optimum design result is obtained by utilizing the optimization program under the new majorized function. A new software, AOS, is developed by applying FORTRAN and VB, which is applicable for the optimization designing of the LiBr-H2O AHT system for recovering the heat of low-temperature waste water and it simplifies the complicated optimization designing. The optimum design of an actual villa district is completed by using the AOS software and the economical efficiency, energy-saving efficiency and environment efficiency are discussed. The results of discussion show, the economical efficiency, energy-saving efficiency and environment efficiency of the LiBr-H2O AHT system is excellent under certain conditions, contrasting to the oil-fired boiler, the gas-fired boiler, medium-high temperature heat pump and the city heating net.