| 摘要 |
A filter retention module of a sand filter apparatus for treating water includes a filtrate outlet arrangement from which filtrate can be supplied. A filtrate inlet arrangement is capable of connection to the filtrate outlet arrangement of a further filter retention vessel module. A waste inlet arrangement is in fluid communication with each filter retention vessel module and is connectable to a supply of waste water. A waste outlet arrangement is capable of connection to the waste inlet arrangement of a further filter retention vessel module. A filter is interposed between the waste inlet arrangement and the filtrate outlet arrangement, the filter including two layers of aggregate and a layer of sand interposed between the two layers of aggregate, the sand being at least one of, or a mixture of, granite-based sand and substantially pure silica sand. A distribution arrangement is connected to the inlet arrangement and is configured to distribute waste water from the inlet arrangement onto the filter. |
