Multi media filter is also known as mechanical filter (now some people call quartz sand filter as multi-media filter, because quartz sand particle size is different, divided into 2-3 specifications), mechanical filter, alias many, is actually the same filter, in water treatment process, is the most commonly used mechanical filtering equipment, because the filter material is cheap, environmental protection, filtering effect So quartz sand filter has been fully used in water treatment.

多介质过滤器为什么要进行反洗呢？我们从多介质过滤器的作用说起，多介质过滤器主要是过滤与拦截水中的悬浮物，泥沙，有机物等杂质。过滤原理主要是通过石英砂截留来的，所以多介质过滤器工作一段时间后，砂的缝隙间有许多的细小颗粒物，如泥，有机物等杂质等。如果不对其进行反洗，过滤罐体内拦截的泥沙等杂质会越积越多，从而影响了源水的通过性，并使出水压力变小，过滤流量减少，不但浪费了宝贵的能源（电能，水泵提供动力），而且出水水质不达标，所以，多介质过滤器使用一段时间后必须要进行反洗工作。

Why should the multi-media filter be backwashed? First of all, we start from the role of multi-media filter, multi-media filter is mainly to filter and intercept suspended solids, sediment, organic matter and other impurities in the water. The filtration principle is mainly intercepted by quartz sand, so after the multi-media filter works for a period of time, there are many fine particles between the sand gaps, such as mud, organic matters and other impurities. If it is not backwashed, the sediment and other impurities intercepted in the filter tank will accumulate more and more, which will affect the trafficability of the source water, reduce the outlet pressure, and reduce the filtration flow, which not only wastes valuable energy (electric energy and pump power), but also the effluent quality is not up to standard. Therefore, the multi-media filter must be backwashed after a period of time.

多介质过滤器有两种反洗方式，一种是气水反洗，另外一种是水反洗。

There are two backwashing methods for multi-media filter, one is air-water backwashing, the other is water backwashing.

气水反洗：是利用空气的气泡还有石英砂滤料两者相互摩擦，再者就是利用石英砂滤料的颗粒与颗粒之间的摩擦力，也就是利用石英砂滤料和水相冲的摩擦力，四者相互作用，在的限度上增加了反冲洗的效果，这样经过反水洗后的石英砂滤料就可以进行正常使用。优点是：反洗时间较短，耗水量少。所以工泉水处理科技有限公司反洗方法是：汽水反洗

Air water backwashing: the air bubble and quartz sand filter material are used to rub each other, and the friction force between the particles of quartz sand filter material is used, that is, the friction force of quartz sand filter material and water is used. The interaction of the four factors increases the backwashing effect to the maximum extent, so that the quartz sand filter material after backwashing can be operated normally Use. The advantages are: shorter backwashing time and less water consumption. Therefore, Gongquan Water Treatment Technology Co., Ltd. recommended backwashing method is: steam water backwashing