Wastewater can offer a favorable solution for wastewater treatment. This work reviews series of filters with different particle sizes, namely pozzolan and sawdust, as an alternative for wastewater treatment. A permeability coefficient was determined for each filter. The biofilm was prepared by passing a stream of wastewater containing bacteria through different filters separately. The purification of wastewater was performed on the biofilm with different particles sizes. The results show an inverse relationship between the permeability coefficient and the contact time that affects the efficiency of the filtration. Filtration efficiency yield is around 85–94% for chemical oxygen demand (COD) and around 92–97% for biological oxygen demand (BOD). High efficiency in removing some minerals is also observed by bacteria. The biofilm prepared from wastewater seems to be an efficient agent to filter wastewaters in particular rural areas. The formation of biofilms has significantly reduced bacterial activity and heavy metal content.

中文翻译：

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火山灰和锯末作为生物滤池处理废水的效率

废水可以为废水处理提供有利的解决方案。这项工作回顾了一系列具有不同粒径的过滤器，即火山灰和锯末，作为废水处理的替代方案。确定每个过滤器的渗透系数。通过使含有细菌的废水流分别通过不同的过滤器来制备生物膜。废水的净化是在具有不同粒径的生物膜上进行的。结果表明，渗透系数与接触时间之间存在反比关系，影响过滤效率。化学需氧量（COD）的过滤效率约为85-94％，生物需氧量（BOD）的过滤效率约为92-97％。细菌还观察到去除某些矿物质的高效率。由废水制成的生物膜似乎是过滤特定农村地区废水的有效剂。生物膜的形成显着降低了细菌活性和重金属含量。