| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a sewage septic tank having filter bed tanks in which water passing plates forming filtering layers in either an anaerobic filter bed tank or an aerobic filter bed tank can be easily replaced and which is efficient in the operation such as maintenance and inspection. SOLUTION: In this sewage septic tank having filter bed tanks packed with filter mediums, filter bed tanks 26 are arranged in approximately quadrilateral shapes on a plane view and water passing plates 27 are provided in the upper and lower parts of the filter bed tanks 26 and a filtering layer packed with filter mediums is formed between the water passing plates 27. The water passing plates 27 are put on receiving parts 31 in convex shapes horizontally and inward from the circumference of the sidewalls of the filter bed tanks 26, and are latched by the projections 32 formed inward and horizontally with a space above the receiving parts 31 on a pair of side walls facing each other out of all the sidewalls, and the water passing plates 27 are provided with notches larger than the projections 32 on the end surfaces of the sides latched by the projections 32. The water passing plates 27 can be replaced by making the notches of the water passing plates 27 meet the projections 32 by sliding the water passing plates 27 horizontally.</p> |
