求翻译：在过滤周期中，原水自顶向下通过过滤器。当水通过核桃壳介质的时候，游离油和悬浮固体被除去。经过了24小时的过滤后，原水会改变流向， 脉冲注入过滤器底部，流化过滤介质。此外，它还通过某种方式加入空气或工艺气体，产生气提作用。气提作用将带有污染物的介质提升到过滤器顶部，通过反冲洗水和气体的湍流将油和悬浮固体从核桃壳介质的表面分离。使用气反冲，可以显著降低反冲洗水量。汽水混合体在一个外部容器中进行汽水分离。外部分离器可被多个核桃壳过滤器共用。反冲洗周期结束后，原水会再次返回到容器顶部。是什么意思？

In the filtration cycle, water from the top down through the filter. When the water through the walnut shells when the media, free of oil and suspended solids are removed. After a 24-hour filter, would change the flow of raw water, pulse injection filter bottom fluidized filter media. In addition, it also joined the technology of air or gas in a certain way, air-lift role. Gas stripping with pollutants of media promotion to the top of the filter, by Backwashing water and gas turbulence walnut shell oil and suspended solids from the media surface of separation. Use of recoil, can significantly reduce the backflush quantity. Steam-water mixture in an outer container for water-steam separation. External separation of walnut shell filter may be more common. After the end of the backwash cycle, water will again return to the top of the container.