| 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 formed in approximately quadrilateral shapes, as plan-viewed, in the said septic tank, and water passing plates 27 are arranged in the upper and lower parts of the filter bed tanks 26, and a filtering layer packed with the filter mediums is formed between the water passing plates 27. The water passing plates 27 are put on receiving parts 30 in convex shapes horizontally and inward from the circumference of sidewalls of the filter bed tanks and are latched by the projections 32 formed inward and horizontally above the receiving parts 30 on a pair of sidewalls 31 and 32 facing each other out of all the sidewalls, and the water passing plates 27 can be replaced by being bent at almost the center 33 of the sidewalls facing each other, provided with the projections 32.</p> |
