• Title/Summary/Keyword: 양액재배

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Optimal Conditions for As(III) Removal by Filtration System Packed with Different Ratio of Iron-Coated Sand and Manganese-Coated Sand (철 및 망간코팅사 충전비를 달리한 여과시스템에서 3가 비소 제거의 최적 조건)

  • Chang, Yoon-Young;Kim, Kwang-Seob;Song, Ki-Hoon;Yang, Jae-Kyu
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.11
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    • pp.1186-1191
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    • 2006
  • Removal efficiency of As(III) through oxidation and adsorption in column reactors was investigated at different ratios of manganese-coated sand(MCS) and iron-coated sand(ICS) : MCS-alone, ICS-alone and both of ICS and MCS. The breakthrough of arsenic immediately occurred from a column reactor with MCS-alone. However, most of the arsenic present in the effluent was identified as As(V) due to the oxidation of As(III) by MCS. While five-times delayed breakthrough of arsenic was observed from a column reactor with ICS-alone. At a complete breakthrough of arsenic, the removed As(III) was 36.1 mg with 1 kg ICS. To find an optimum ratio of ICS and MCS in the column packed with both ICS and MCS, the removal efficiency of As(III) was investigated at three different ratios of ICS/MCS with a fixed amount of ICS. The breakthrough time of arsenic was quite similar in the different ratios ICS/MCS. However, much slower breakthrough of arsenic was observed as the ratio of ICS/MCS decreased. As the ratio of ICS/MCS decreased the concentration of As(III) in the effluent decreased and then showed below 50 ppb at an equal amount of ICS and MCS, suggesting more efficient oxidation of As(III) by greater amount of MCS. When a complete breakthrough of arsenic occurred, the removed total arsenic with an equal amount of ICS and MCS was 68.5 mg with 1 kg of filter material.

Effects of Several Cooling Methods and Cool Water Hose Bed Culture on Growth and Microclimate in Summer Season Cultivation of Narrowhead Goldenray 'Ligularia stenocephaia' (곤달비 여름재배 시 냉각방법과 냉수호스베드재배가 생육 및 미기상에 미치는 영향)

  • Kim, Ki-Deog;Lee, Eung-Ho;Kim, Won-Bae;Lee, Jun-Gu;Yoo, Dong-Lim;Kwon, Young-Seok;Lee, Jong-Nam;Jang, Suk-Woo;Hong, Soon-Choon
    • Journal of Bio-Environment Control
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    • v.20 no.2
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    • pp.116-122
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    • 2011
  • This study was carried out to investigate the effects of several cooling methods such as water hose cooling, mist, fog and control on growth and microclimate, and to develop a simple nutriculture bed for production of fresh leaves of narrowhead goldenaray 'Ligularia stenocephala'. When the root-zone was cooled with 240 L/hr flow rate of $13^{\circ}C$ ground water using water hose, the temperature was lowered approximately by 2 to $3^{\circ}C$ than that of control. The growth of narrowhead goldenaray were favorable in the water hose cooling compared with the other cooling methods. Nutrient culture system having part cooling effect around plant canopy was developed. The system was composed of 15 cm diameter of water hose on side wall of beds, cooling hose, and expanded rice hull media as organic substrate. When cool water which the temperature changed in the range of 14 to $22^{\circ}C$ diurnally with 240 L/hr of flow rate through water hose, the air temperature around canopy and root-zone temperature were dropped by $0.5^{\circ}C$ and $3^{\circ}C$ compared with that of conventional styrofoam bed, respectively. These results showed that newly devised bed system using water hose was simple and economical for the production of high quality narrowhead goldenaray leaves. This system might be practically used both at summer and winter season for the cultivation of narrow head goldenaray by part cooling or heating around root-zone and plant canopy.