Study of Reduced Water Washing by Novel Fluidized System

本研究的主要成果如下：1.对BUR的主要研究内容进行了实验研究，取得了有价值的结果。(1)将小颗粒大密度颗粒模拟为洗涤废弃物，模拟农产品洗涤过程中的泥浆，考察了添加小颗粒大密度颗粒对床层流体动力学及颗粒分离与去除系统的影响。得出了颗粒添加的最佳操作条件，并提出了适用于小颗粒分离与去除的分布板结构。(2)提出了该新型流态化系统的流态化洗涤机理，即流态化洗涤由两种洗涤特性组成，一种是硬冲击洗涤，如去除农产品中的泥浆；另一种是软磨料洗涤，如去除工业现场的油污。(3)和(4)的后续实验结果成功地支持了这一机理。(3)研究了石膏层覆盖试管中颗粒碰撞费用与磨损率之间的关系，明确了气速、加水和添加小颗粒对颗粒碰撞速率的影响。通过对比新型沸腾床和无颗粒鼓泡水流的磨损特性，确定了颗粒碰撞力是硬冲击清洗的主要因素。(4)另一方面，从覆盖在试管上的标准污布的白化试验结果来看，软磨料洗涤等另一种洗涤特性也起到了流态化洗涤的作用，这些研究结果对该新型流态化系统的流体力学和洗涤特性有了新的科学认识，也为该流态化系统应用于工业洗涤设备提供了有效的设计指导。

The results of this study is summarized as follows, the bur principal research items as mentioned below were investigated experimentally and valuable results were obtained. (1) The influence of addition of small large-density particles into this novel fluidized bed on bed hydrodynamics and the particle separation and removal system were investigated The small large-density particle simulated as washing waste as mud thr farm products washing. As the result, the optimum operation condition for particle addition was presented and the appropriate configuration of distributor for small-particle separation and removal was proposed. (2) The mechanism for fluidization washing in this novel fluidized system was proposed, ie., the fluidization washing composed of two washing characteristics, one is a hard-impact washing such as mud removal from farm products and another is a soft-abrasive washing such as oil soil removal from industrial works. The mechanism was supported successfully by the next experimental results of (3) and (4). (3) The relationship between particle collision fare and attrition rate of the test tube covered with plaster layer was investigated and the influence of gas velocity, addition of water and addition of small particles were clarified. Comparing with the attrition characteristics in both the novel fluidized bed and the bubbling water flow without any particles, the principal factor for a hard-impact washing was identified the particle collision force. (4) On the other hand, from the result of whitening test of standard soiled cloth covered the test tube, another washing characteristics such as soft-abrasive washing also acts far fluidization washing.These whole findings give a new scientific understanding about hydrodynamics and washing characteristics of this novel fluidized system and also give an effective design guideline for industrial washing devices as the application of this fluidized system.