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Soil acidification is one of the rising land degradation issues facing world agriculture. The risk of acidification is currently being assessed as part of agriculture productivity and sustainable theme. This study was conducted to produce a new vermicomposting cast as a recycling resource derived from municipal sewage sludge and waste oyster shell. The earthworm, Eisenia Andrei, was fed under different conditions. The most suitable mixture was 77:23 w/w% of sewage sludge and waste oyster shell. Powdered oyster shell (POS) sludge blend provided a stable pH, due to its buffering capacity during vermiculture because of the Ca2+ and OH? release effect. The vermicast products fulfilled the cast standards of Korea Ministry of Environment for all the parameters such as moisture content, pH, salinity, organic carbon, TKN, Phosphate, and heavy metals. Slowly released organic matter when added to soil improves the capacity of the soil to hold nutrients for plants, improve soil aeration for roots, and improves soil drainage. This product will be an addition to already-commercialized sludge vermicast as a higher value product. 相似文献
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Joong Kee Lee Dalkeun Park Byeong-Uk Kim Jong-In Dong Sangwha Lee 《Waste management (New York, N.Y.)》1998,18(6-8)
A novel type of fluidized bed desorber was developed for the remediation of petroleum-contaminated soils at low temperature with high efficiency. Cahn balance® was utilized to investigate the thermal desorption behavior of soils contaminated by various hydrocarbons. The performance of the fluidized-bed desorber was investigated at different operating modes. Batch operation of the fluidized-bed desorber exhibited 99.9% desorption efficiency at temperatures of ca. 300°C within a half hour. Continuous operation of the fluidized-bed indicated that Q/F (the ratio of the mass flow rate of fluidizing gas to feeding rate of contaminated soils) is less important at higher temperature (>300°C), if proper fluidization is ensured. The periodic operation of the fluidized bed desorber shows the possibility to reduce off-gas volume significantly. 相似文献
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This study was to assess the metal contamination in oyster tissue grown in the Ann-ping mariculture ground in Taiwan. the information generated from this work also revealed general metal pollution problem for Taiwan's oyster farmers. Oysters, Crassostrea gigas, and surficial sediments collected from ten locations in Ann-ping mariculture ground in Taiwan for metals concentration (Cu, Zn, Pd, Cd, Fe and Mn) were performed. Analytical results indicated that the yearly averaged oyster copper concentrations (μg g-1, wet weight) in oyster soft parts from Ann-ping increased from 21.3±4.1 in 1993; 24.1±6.8 in 1994; 36.8±11.9 in 1995 to 43.9±23.1 μg g-1, wet weight, in the 1996 raising season. the mean oyster copper concentration reached a level of 50 μg g-1, wet weight, in December 1996. This increasing trend of metal concentration in oyster tissue indicates a potential pollution source which may pose a potential disaster as green oyster incidence, which occurred on the Charting coast in 1986, in Taiwan. Sediment samples in Ann-ping mariculture ground were also collected and examined. the seasonal variation of the copper concentration in surficial sediment from Ann-ping did not show an increasing trend as observed in oyster tissue. 相似文献
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Alireza A. Shamshirsaz Kelsey A. Stewart Hadi Erfani Ahmed A. Nassr Nathan C. Sundgren Amy R. Mehollin-Ray Shaine A. Morris Jimmy Espinoza Magdalena Sanz Cortes Christopher Cassady Timothy C. Lee Eumenia C. Castro Olutoyin A. Olutoye Deepak K. Mehta Darrell Cass Oluyinka O. Olutoye Michael A. Belfort 《黑龙江环境通报》2019,39(4):287-292
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