검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 51

        22.
        2008.05 KCI 등재 서비스 종료(열람 제한)
        The application of microwave technology has been investigated in the remediation of diesel-contaminated soil. The paper deals with economic assessment by means of cost analysis and degradation characteristics at different microwave powers for total petroleum hydrocarbon (TPH) in diesel contaminated soils. The soils from S Mountain around the D University were sampled. The samples were screened with 2.0 mm mesh and dried for 6 hours before the diesel was added into the dried soils. The diesel-contaminated soil (3,300 mg THP/kg soil) was prepared with diesel (S Co.). The drying process was carried out in a microwave oven, a standard household appliance with a 2,450 MHz frequency and 700 W of power. The experiments were conducted from 0 to 20 minutes as the microwave powers increased from 350W to 500W to 700W. The concentrations of TPH were analysed using a gas chromatography/mass spectrometer (GC/MS). The initial concentration of TPH was 3,300 mg TPH/kg soil. The weight of contaminated soil was 200g. The concentration of TPH was decreased to 1,828 mg TPH/kg soil (44.7%), 1,347 mg TPH/kg soil (59.2%) and 1,014 mg TPH/kg soil (69.3%) at 350W, 500W and 700W for 15 minutes respectively. In addition, the curve was best fit with first order kinetics using the least-square method. The ranges of a first order rate constant k and r-square were 0.0298~0.0375min-1 and 0.9373~0.9541 respectively.
        24.
        2008.04 KCI 등재 서비스 종료(열람 제한)
        The purpose of this study is to investigate weighted compaction density according to a loading density in truck, a compaction density of solid waste and composition ratios of solid waste for calculation of a capacity of the landfill sites. The experiments for calculations of in-place density at landfill site have been conducted in S landfill site at B City. The size of vessel for measuring the compaction density was 1m3(1m×1m×1m). The experiment tests have been carried out methods (1 time for bulldozer and 4 times for compactor) that do contain all of specification at the landfill site. Average of the loading density at the landfill site was 0.264 ton/m3 (0.113~0.487 ton/m³). When the loading density for each compositions was compared, the composition of the highest average loading density (0.474 ton/m³) was miscellaneous wastes. The composition of the lowest average loading density (0.120 ton/m³) was general solid waste. The reported results indicated that the compaction density at the landfill site was 0.538 ton/m³, which was calculated with weighted incoming ratios of compositions. The ranges of the density for each composition were from 0.021 ton/m³ to 0.221 ton/m³. When the compaction density for each composition was compared, the composition with the highest average compaction density (0.221 ton/m³) was miscellaneous wastes. The composition with the lowest average compaction density (0.021 ton/m³) was general solid wastes.
        25.
        2008.01 KCI 등재 서비스 종료(열람 제한)
        This study examined the contaminated soils with an indicator of TPH using SVE (Soil Vapor Extraction) and biological treatments. Their results are as follows. Water content in the polluted soils slowly decreased from 15% during the initial experimental condition to 10% during the final condition. Purification of polluted soils by Bioventing system is likely to hinder the microbial activity due to decrease of water content. Removal rate of TPH in the upper reaction chamber was a half of initial removal rate at the 25th day of the experiment. The removal rate in the lower reaction chamber was 45% with concentration of 995.4 mg/kg. When the Bioventing is used the removal rate at the 14th day of the experiment was 53%, showing 7 day shortenting. Since the Bioventing method control the microbial activity due to dewatering of the polluted soil, SVE mehtod is likely to be preferable to remove in-situ TPH. The reactor that included microbes and nutrients showed somewhat higher removal rate of TPH than the reactor that included nurtients only during experimental period. In general, the concentration showed two times peaks and then decreased, followed by slight variation of the concentration in low concentration levels. Hence, in contrast to SVE treatment, the biological treatment tend to show continuous repetitive peaks of concentration followed by concentration decrease.
        38.
        2004.01 KCI 등재 서비스 종료(열람 제한)
        In this study, sulfate reduction reaction was used to increase the decomposition of organics, which is the most critical factor for the stabilization of a landfill site. Composite of sewage sludge, papers, and incineration ashes was used in the column. The experimental results indicated that out of 10 reactors, the reactors 3, 4, 8, and 9 showed higher organics (i.e., TOC) removal rate than that in the absence of sulfate. The organics removal rates (K) in R3 and R9 were 8.65e-4/d and 3.82e-4/d, respectively. The times to reach 10% of initial concentrations in R3 and R9 was 7.3 and 16.5 years, respectively, showing faster organics decomposition rates in these reactors.
        1 2 3