| Project/Area Number |
60480073
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
農業土木
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| Research Institution | Kyoto University |
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Principal Investigator |
TSKAHASHI TSUYOSHI (1986) Associate Proffesor, Faculty of Agriculture,Kyoto University, 農学部, 助教授 (80021707)
高橋 つよし (1985) 京都大学, 農学部, 助教授
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| Co-Investigator(Kenkyū-buntansha) |
ARITA HIROYUKI Chief of Rural planning lab., Dept. of Agricultural Development, National Agricu, 農業研究センター農業計画部, 室長
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| Project Period (FY) |
1985 – 1986
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| Project Status |
Completed (Fiscal Year 1986)
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| Budget Amount *help |
¥6,600,000 (Direct Cost: ¥6,600,000)
Fiscal Year 1986: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1985: ¥4,500,000 (Direct Cost: ¥4,500,000)
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| Keywords | Rural community sewage treatment / Tertiary Treatment / Denitrification / 脱リン |
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| Research Abstract |
Recently major lakes and marshes including Lake Biwa and Lake Kasumigaura have been in an advanced stage of pollution. In order to prevent it, it is necessary to check the inflow of nutrient salts such as nitrogen and phosphorus. Therefore, not only the removal of BOD and SS but also tertiary treatment for the removal of nitrogen and phosphorus from the sewage required even in rural areas.
In this study, field and laboratory experiments were carried out in order to clarify the fundamental characteristics of the tertiary treatment of nitrogen and phosphorus of the sewage and also to develop the new sewage treatment method, which is adaptable to the small-scale sewage treatment facilities such as those of rural community.
In the new simultaneous removal method of nitrogen and phosphorus, nitrogen removal method by intermittent aeration and phosphorus removal method by iron filter material were combined, and the high rate removal not only of phosphorus but also of nitrogen was obtained from laboratory experiments, compared with the case without iron contact filter.
By our treatment method, iron ions eluted from iron filter was chemically combined with phosphoric acid ions present in sewage to form hardly soluble amorphous substances, and then removed together with excess sludge. It was hardly resolved to supernatant liquor in sludge thickener, therefore a high rate removal of phosphorus could be obtained.
Amorphous substances including ferrous phosphate, which are hardly soluble, can be useful as phosphatic fertlizer for farmland or for iron supplementation for infertile paddy field, therefore this proposed method appears to be promising to apply for the rural community sewage treatment facilities.
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