Hydraulic pump driven by a low temperature difference

50 - 60 C的温水（来自工业的热废水或太阳能集热器的热水）和10 - 20 C的冷水之间的低温差可以用于操作液压泵。该泵使用氟利昂11 （CC1_3F：沸点在24个大气压下）作为工作流体。过去三年，我们在发展科学研究补助金的支持下，分三个阶段进行了研究：1)塑料气球泵2)活塞驱动泵3)氟利昂蒸汽-水直接接触泵。塑料气球的困难在于塑料材料不能长时间工作。活塞驱动泵适合长期运行，但也存在摩擦损失较大的缺点。氟利昂蒸汽-水直接接触型与充水u型管泵一起工作。这种泵的唯一缺点是氟里昂在水中有轻微的溶解。然而，溶解度（0.011g-氟里昂/g-水）是如此之小，这种类型的泵是很好的长期使用。

Low-level temperature difference between warm water at 50 - 60 ﾟC (warm waste water from industry or warm water made in a solar energy collector) and cold water at 10 - 20ﾟC may be used for operating a hydraulic pump. The pump uses Freon 11 (CC1_3F: boiling point at atmospheric pressure of 24ﾟC) as a working fluid.In the past three years with the support of the grant-in-aid for developmental scientific research we carried out research in the following three phases: i) plastic-balloon pump ii) piston-driven pump iii) Freon vapor - water direct-contact pump The difficulty with a plastic balloon was that no plastic material worked out well for long. A piston-driven pump was good for long term operation, but again some-disadvantage was with a considerable amount of friction loss. The Freon vapor - water direct-contact type worked with a water - filled U-tube pump. Only the disadvantage of this pump arises from a slight dissolution of Freon into water. However, the solubility (0.011g-Freon/g-water) is so small that this type of pump was good for long term use.