太陽エネルギー利用の高効率塩水淡水化システムに関する研究

利用太阳能从微咸水或海水中制取淡水有多种方法。最简单和最常用的方法是在盆式太阳能蒸馏器中直接利用太阳能，该太阳能蒸馏器同时充当太阳能到热量的转换器和蒸馏器。本研究旨在分析双斜面盆式蒸馏器的基本性能，并提出带蒸发促进器的盆式太阳能蒸馏器的新概念。实验和理论研究结果表明：（1）蒸馏器覆盖材料的不同，蒸馏水的收集效果也不同。经防水滴处理的硬质聚酯薄膜对水的收集效果最好，而太阳能内对流风扇仍能使蒸馏水的收集量增加约10%。当采用3.5%的盐水作为源水时，与采用自来水相比，纯水产量降低了10%左右。2）对池内每种辐射吸收体加载超声振荡，生产率提高了10 ~ 20%。与无吸收体情况相比，在无超声振荡条件下，水面采用黑色塑料多孔板的纯水产率提高了约20%;在超声振荡条件下，水面采用黑色塑料多孔板的纯水产率提高了约50%。3）利用热平衡方程对太阳能蒸馏器的性能进行了数值计算，并与实验结果进行了比较。计算值与测量结果吻合较好。该计算方法可用于水池水温和水量的估算。4）介绍了多效太阳能蒸馏器，并对其性能进行了测试。该蒸馏器的纯水产量约为普通盆式太阳能蒸馏器的7倍。

There are many ways of solar energy application in producing fresh water from brackish or seawater. The simplest and most common method is direct use of the solar energy in basin-type solar still which acts simultaneously as converters of solar energy to heat and as distillers. Objectives of this study is to analyze the basic performance of double slope basin-type stills and to develop the new concept for basin solar still equipped with evaporation stimulator. Results from experimental and theoretical works are as follows :1) The effectiveness of gathering distilled water was varied with the kinds of covering materials for still. Rigid polyester film with anti-droplet treatment was most efficient to gather the water, and inner convection fan in solar still increased the amount of distilled water about 10% more. When the salt water of 3.5% concentration was used as source water, output of pure-water was decreased about 10% by comparing with use of tap water.2) Productivities increased by about 10 to 20% when ultrasonic oscillation was loaded for every three types of radiation absorber in the basin. In comparison with no absorber condition, productivity of pure water using black plastic perforated sheet on water surface increased by about 20% without ultrasonic oscillation, and increased by about 50% with the ultrasonic oscillation.3) Numerical calculation estimating performance of solar stills was done by using heat balance equation, and compared the results of calculation with those of experiments. Calculated values fairly fit the result of measurement. This calculation method seems to be useful for estimating the temperature of basin water and output of water.4) Multi-effect type solar still was introduced and their performance was examined. Output of pure water in this still was about 7 times of the usual basin type solar still.