• Resources Recycling
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• v.18 no.1
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• pp.22-29
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• 2009

To design and construct a moving bed stoker incinerator for incineration treatment of the domestic oil fly ash, operating condition and moving bed area of incinerator were determined by performing incinerate experiment of the oil fly ash in the muffle furnace which simulates moving bed stoker incinerator in all conditions. Incineration process of the oil fly ash could be divided into 3 stages, every stage needs the appropriate operating condition for effective incineration. The optimum content of water in the heavy oil fly ash was found to be 20 wt% to prevent the ash from flying and reduce the volume. Science combustion rate of oil fly ash depends on the oxygen content, the incinerator must have a equipment to control the oxygen content in the combustion air. The optimum temperature was $750{\sim}800^{\circ}C$ in order to prevent adhesion to the stocker and evaporation of metal compounds of low melting point. Uniform combustion reaction and acceleration of combustion rate required agitation during the combustion of oil fly ash. The incineration rate was $12.53kg/m^2hr$ and the working area of moving bed incinerator was found to be $60m^2$ to incinerate 18 tons of oil fly ash per day.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.167-172
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• 1984

The aluminum composition of the citrus orchard soils (volcanic ash soil) in Cheju Island was studied. The content of extractable Al was high, especially for the sub-soil. However the exchangeable Al was relatively low : it was only one-tenth of the extractable Al content. The exchangeable Al of the citrus orchard soils decreased with increasing number of years of cultivation. This has resulted from an increase in pH. The content of the extractable Al of the citrus orchard soils also decreased with the increase in number of years of cultivation. This is related to the fact that the application of phosphate fertilizers led to a reduction in Al activity. Therefore, the extractable Al showed a highly significant correlation with the available phosphorus in the top soil. However it was not significantly affected by phosphates in the sub-soil where the available phosphorus was extremely low. The extractable Al content strongly correlated with the organic matter and pH(NaF) in the sub-soil, but the correlation was less significant in the top soil. This suggests that large amounts of the extractable Al are released from the hydrous oxides of Al and that the organically complexed form in the sub-soil and non-extractable due to the reactions with phosphates applied to the top soil.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.5
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• pp.238-246
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• 2005

We conducted this investigation to observe competitive adsorption phenomena among the heavy metals onto the available sorption sites of soil particle surfaces in sandy clay loam and clay soil collected from Nonsan city, Chungnam and Yoosung, Daejeon in Korea, respectively. Polluted and contaminated soils can often contain more than one heavy metal species, resulting in competition for available sorption sites among heavy metals in soils due to complex competitive ion exchange and specific sorption mechanism. And the adsorption characteristics of the heavy metals were reported that the selectivity for the sorption sites was closely related with electropotential and electro negativity carried by the heavy metals. The heavy metals were treated as single, binary and ternary systems as bulk solution phase. Adsorption in multi-element system was different from single-element system as Cr, Pb and Cd. The adsorption isotherms showed the adsorption was increased with increasing equilibrium concentrations. For binary and ternary systems, the amount of adsorption at the same equilibrium concentration was influenced by the concentration of individual ionic species and valence carried by the respective heavy metal. Also we found that the adsorption isotherms of Cd and Pb selected in this experiment were closely related with electronegativity and ionic potential regardless number of heavy metals in solution, while the adsorption of Cr carried higher valance and lower electro negativity than Cd and Pb was higher than those of Cd and Pb, indicating that adsorption of Cr was influenced by ionic potential than by electronegativity. Therefore adsorption in multi-element system could be influenced by electronegativity and ionic potential and valance for the same valance metals and different valance, respectively. But it still needs further investigation with respect to ionic strength and activity in multi-element system to verify sorption characteristics and reaction processes of Cr, especially for ternary system in soils.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.767-772
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• 2011

The purpose of this study was to find out required time for recovery of nutritional disorder by Fe-DTPA treatment in induced Fe-deficient tomato cultivars and to select stable Fe-chelate in high pH of nutrient solution. The pH levels of nutrient solution were amended with 6.0, 7.0, and 8.0. Then Fe-EDTA (Ethylenediaminetetraacetic acid, ferric-sodium salt), Fe-DTPA (Sodium ferric diethylenetriamine pentaacetate), and Fe-EDDHA (Ethylenediamine-N,N-bis (2-hydroxyphenylacetic acid) ferric-sodium salt)) were treated as Fe $2.0mg\;L^{-1}$ concentration. The Fe-DTPA and Fe-EDDHA were stable in the nutrient solution of pH 6.0~8.0 but Fe-EDTA in nutrient solution of pH 8.0 was to become insoluble by 25%. The Fe $2.0mg\;L^{-1}$ as Fe-DTPA was treated for recovery of Fe deficient tomato seedlings. In case of Redyoyo and Supersunroad cultivars, total chlorophyll and Fe contents of leaves were recovered as much as those of normal leaves in 5 days. The Rafito cultivar for complete recovery was taken 7 days. When Fe $2.0mg\;L^{-1}$ as Fe-DTPA was supplied to Fe-deficient tomato seedlings, in geotype, heme oxigenase recovered as much as normal leaves in 24 hours in the Rafito and Redyoyo. However, it was not remarkable difference by elapsed time in the Supersunroad.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1063-1070
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• 2011

In this study, total of 5 different chemical amendments were evaluated for determining kinetic parameters and stabilization efficiency of heavy metals in aqueous phase. Standard solution of Cd and Pb ($100mg\;L^{-1}$) was mixed with various ratio of amendments (1, 3, 5, 10%) and heavy metal stabilization efficiency was monitored for 24hrs. All examined amendments showed over 90% of removal efficiency for both Cd and Pb except zerovalent iron (ZVI) for Cd (43-63%). Based on result of heavy metal stabilization efficiency, it was ordered as $CaCO_3$ > Dolomite > Zeolite > Steel slag > ZVI for both Cd and Pb in aqueous phase. For kinetic study, first order kinetic model was adapted to calculate kinetic parameters. In terms of reaction rate constants (k), zeolite showed the fastest reaction rate (k value from 0.4882 for 1% to 2.0105 for 10%) for Cd and ZVI (k value from 0.2304 for 1% to 0.5575 for 10%) for Pb. Considering reaction rate constant and half life for heavy metal stabilization, it was ordered as Zeolite > $CaCO_3$ > Dolomite > Steel slag > ZVI for Cd and $CaCO_3$ > Dolomite > Steel slag > Zeolite > ZVI for Pb. Overall result in this study can be interpreted that lime containing materials are more beneficial to remove heavy metals with high efficiency and less time consuming than absorbent materials.