| With the rising requirement for living conditions and intensification on energy saving or environmental protection by public, the conflicts among architecture, energy and environment become more and more drastic. Nowadays, architecture has already ranked the fastest increasing section in energy consumption. The portion of energy consumption by construction will rapidly increase to about 1/3 of total, at the same time, heating and air-conditioning consumption played the most important role in this portion. And dehumidifying energy consumption occupies 20～50% of the air-condition energy consumption. As to Yangtze River valley, the conflict between thermal environment and energy consumption of building is growing day after day, owning to its special geographical conditions and rapid development in economy and urbanization. Also, this zone is called hot in summer and cold in winter zone, according to climate subarea. It's hot and damp in summer, cold and bleak in winter, with high humidity all over the whole year round. So dehumidify is significance in this area. Differing from other dehumidifying methods, rotary and liquid dehumidifications belong to absorption (sorption) dehumidifying method, as they have an advantage of regeneration. Rotary dehumidifier is composed of dehumidifying wheel and regenerative heater. 80% energy consumption is used for regeneration of dehumidizer. Liquid desiccant air conditioning is able to use low-grade heat; and that helps to saving energy, protecting environment, and improving indoor air quality, it has abilities of removing germs and energy accumulation as well. Because it's a brand new air conditioning technology, many countries have already plunged into its researching and designing.Humiture independent controlling AC system is regarded as an efficient way which benefits reducing energy consumption, improving indoor air quality and optimizing energy structure. According to this conception, characteristics of climate along Yangtze River Valley were summarized. Indoors and outdoors humidity loads among nine big cities in this area were analyzed as well. Then the thermal environment designing index of indoor and outdoor in both winter and summer could be determined. After that numerical calculation and simulation were proceed respectively based on designing parameters of outdoor and meteorological parameters of typical year. The results showed humidity loads'characteristics in these cities: the average humidification load is 696g/h in winter, mean dehumidification load is 3.8kg/h in summer. Furthermore, dehumidification load of fresh air shares 85~88% of the whole humidification load. According to various areas, regression equations were deduced. Moreover, the influences of designing temperature and RH were counted in. And the results indicated that once there is 1℃change of interior setting temperature, the humidity load will change by 125~194g/h. if the interior setting RH changes 10%, then humidity load will change by 450~750g/h. The comparison between results of two measures fingered out that calculating error is within 15 percent, so they have consistency.The devices of humiture independent controlling AC system are discrepant from traditional ones. This article summed up cold/heat sources and terminals of humiture independent controlling system. System can not only make full use of natural cold source, but also increase the efficiency of air conditioning, and it reduces energy consumption. The terminals could be divided into two parts: temperature control and humidity control. Each controlling method could be mated, thus, certain humiture independent controlling system could be established to fit certain conditions. The article released a new practical designing patent based on this conception. Its feasibility was verified. Anyway, this technology has a bright future to be generalized in Yangtze River Valley.Experiments of small-scaled liquid desiccant AC system were described in this article. Firstly, we did the experiment on moisture absorpting performance of anhydrous CaCl2.The result indicated that CaCl2 has strong capacity of hygroscopy, and humidity of air has an crucial effect on its hygroscopy. Besides, we built up an experimental device of small-scaled liquid desiccant AC system to research on dehumidification and regeneration of CaCl2 solution. Experimental results shows that there are 3 factors which mainly works on performance of CaCl2 solution, they are temperature of solution, concentration of solution and humidity of inlet air. The capacity of CaCl2 solution'dehumidification is 3.38g/kg in experimental condition. And the regenerating performance is about 1.3~2.9 times than that of dehumidifying. After summarizing, liquid desiccant dehumidification with CaCl2 solution has large potential to be improved and generalized.
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