Aeration and Heating Improve Slow Sand Filtration as a Disinfection System for Closed Hydroponic Systems
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- MINE Yoko
- Faculty of Agriculture, Tokyo University of Agriculture
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- SUEMATSU Masaru
- Taiyo-Kogyo Co., Ltd.
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- SUGIYAMA Nobuo
- Graduate School of Agricultural and Life Sciences, The University of Tokyo
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Abstract
Aeration and heating were used to improve the disinfection activity of slow sand filtration of recirculating nutrient solutions in a closed hydroponic system. Filter performance was evaluated under different running conditions using E. coli elimination efficiency as an indicator of filter performance. Aeration with or without heating during filter ‘ripening’ increased filter performance so much as to obviate differences in performance associated with filtration rate. The filter reduced influent E. coli concentrations by nearly 3 orders of magnitude with aeration. Effluent E. coli concentrations from filters pre-circulated with aeration and heating were over 4 orders of magnitude lower than influent concentrations. Vertical distribution of viable E. coli in an effective slow sand filter which reduced E. coli concentrations from 106 cfu ml-1 to less than 102 cfu ml-1 was mostly in the Schmutzdecke (106∼107 cfu g-1) and first 10 cm of the surface of the sand layer. High-performance filters did not eliminate Ralstonia solanacearum as effectively as E. coli or the fungal pathogens Fusarium oxysporum and Pythium helicoides.
Journal
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- Environment Control in Biology
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Environment Control in Biology 45 (3), 179-187, 2007
Japanese Society of Agricultural, Biological and Environmental Engineers and Scientists
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Keywords
Details 詳細情報について
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- CRID
- 1390001205259725952
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- NII Article ID
- 10021228989
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- NII Book ID
- AA12029220
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- ISSN
- 18830986
- 1880554X
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- NDL BIB ID
- 8965019
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- Text Lang
- en
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- Data Source
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- JaLC
- NDL
- Crossref
- CiNii Articles
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- Abstract License Flag
- Disallowed