For biodiesel purification, water wash process is the simple and efficient purification process compared with the other methods, however, it produces a large amount of highly contaminated wastewater in purification. In the present research, a simple and cost-effective method was adopted to reduce fresh water consumption and to generate less contaminated wastewater in the process of purification. Two different waste frying oils (WFOs) were used as raw materials and single step alkali-catalyzed transesterification process was adopted for production of biodiesel from low free fatty acid content waste oils. After purification, both with and without 5% water pre-wash biodiesel samples were tested to investigate the influence of water pre-wash on the yield and quality of biodiesel as well as the produced wastewater. The purified biodiesel met the standards required to be a diesel alternative with respect to chemical and physical properties. By 5% water pre-wash, the amount of fresh water required for purification was reduced by 60%. Moreover, less contaminated wastewater was generated compared to the wastewater produced by hot water wash method.

对于生物柴油的净化，与其他方法相比，水洗工艺是一种简单而有效的净化工艺，但是，在净化过程中会产生大量的高污染废水。在本研究中，采用一种简单且具有成本效益的方法来减少淡水消耗并在净化过程中产生较少污染的废水。以两种不同的废煎炸油（WFO）为原料，采用单步碱催化的酯交换工艺从低游离脂肪酸含量的废油生产生物柴油。纯化后，对有和没有5％水预洗生物柴油样品进行测试，以研究水预洗对生物柴油和产生的废水的产量和质量的影响。纯化后的生物柴油在化学和物理性质方面符合作为柴油替代品所需的标准。通过5％的预洗水，纯化所需的淡水量减少了60％。而且，与通过热水洗涤方法产生的废水相比，产生的污染更少的废水。