검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 115

        101.
        2013.10 KCI 등재 서비스 종료(열람 제한)
        This paper examined reasonable operating factor for treatment of carcass burial leachate in High Temperature Thermal Desorption (HTTD) and calculated the amount of fuel used in each device using heat and mass balance under condition of 4 scenarios. As a result, we concluded that rotary kiln for dryness and thermal desorption shoud be separated dual type and mixing ratio of sawdust and soil should be restricted no more than 1 : 14. Also, operating temperature should be kept 260, 550, 850 or higher in dryer kiln, thermal desorption kiln and secondary chamber respectively and residence time should be kept 30min in each kiln. The total amount of fuel used in each device was compared under 4 scenarios on the mixing ratio. According to a study, it showed the highest value under the scenario of 1 : 1, which showed 2.5 times higher than the scenario of 1 : 14 in terms of treatment of leachate per unit of LNG.
        102.
        2013.09 KCI 등재 서비스 종료(열람 제한)
        This study analyzed concentration and characteristics of hazardous substances in treatment of leachate from carcass burial areas by using high temperature thermal desorption (HTTD). Concentrations of pollutants emitted from HTTD treatment of leachate contaminated soil of carcass burial sites satisfied the emission standards for 11 pollutants from domestic waste incineration facilities. Dioxin concentration was 0.0060 ng I-TEQ/Sm3 and 0.0061 (0.0055-0.0070) ng ITEQ/ Sm3 in the normal operation condition and the experimental condition, respectively, which are much lower than the MSWI Standard of 0.1ng I-TEQ/Sm3. As a result, it was considered that leachate from carcass burial areas could be treated by high temperature thermal desorption (HTTD).
        103.
        2013.09 KCI 등재 서비스 종료(열람 제한)
        This paper analyzed thermal and carbonization properties of sewage sludge in fixed bed reactor and obtained following results. The heavy metal (Pb, Ni, Mn, Cr, Cu) content of Char showed the highest level at unprocessed sewage sludge, followed by carbonized sludge at 600, 400, and 500oC. It was thought to be mainly due to the yield of char rather than the influence of temperature. Also, the migration-test results of heavy metals satisfied the landfill directive in all samples, which may be possible to use it as landfill cover materials. The concentration of dioxin by changes of pyrolysis temperature was higher in the low temperature conditions and the proportion of PCDDs was higher than that of PCDFs.
        104.
        2013.07 KCI 등재 서비스 종료(열람 제한)
        According to the statistics of the Ministry of Environment, the emission of sewage sludge is increased by 7 ~ 9% yearly. In the future, it will be increased continuously because of extension of sewage disposal plants, high class treatment for removing nitrogen and phosphorus. The objective of this study is to examine the possibility of the carbonization of the sewage sludge by pyrolysis. The pyrolysis behavior of the sewage sludge was investigated by the thermogravimetric analysis as a function of heating rate. In the pyrolysis studies measurements in weight loss was made and reported as a function of test temperature. To minimize energy consumption used for drying sewage sludge, naturally dried sludge were applied evaluate characteristics of thermal and carbonization treatment using a fixed-bed reactor. The most effective treatment temperature of carbonized material production was 400oC. The temperature of highest total yield of char and oil was 500oC. In the pyrolysis studies measurements in weight loss was made and reported as a function of test temperature. According to the result, the optimum pyrolysis temperature of sewage sludge were found to be ranged from 100oC to 600oC, respectively. About 91% of pyrolysis was completed between 100oC and 600oC. If applying the carbonization, it can be easily utilized as the replaced resource of energy(fuel) in the countries whose energy resources are insufficient, like our country.
        105.
        2013.06 KCI 등재 서비스 종료(열람 제한)
        Establishment of emission concentrations of PCDDs and PCDFs in emission gases from 85 domestic crematories were measured. The relationship between PCDDs/DFs and several factors such as structure, equipment and operational state of the crematory is discussed. Furthermore, emission of PCDDs/DFs from all crematories in korea is estimated. The following results are obtained: (1) total concentration (2,3,7,8- substituted isomers) of PCDDs/DFs was 0.113 ~ 14.34 ng/ Sm3, whose TEQ concentration was 1.815 ng-TEQ/Sm3; (2) total emission of PCDDs/DFs from crematories in korea was estimated to be 1.815 g-TEQ/yr.
        106.
        2013.06 KCI 등재 서비스 종료(열람 제한)
        Infectious diseases in domestic animals of carcase were increasing every year. According to the monthly report for infectious disease from Ministry for Food, Agriculture, Forestry and Fisheries, 11,954 heads of cattle, 518,178 heads of pig, 232,850,244 heads of bird were reported in 2011. Infectious diseases of carcase almost spread on a national scale. Dead or emergency preventive carcase are completely treated on bury. Since the treatment of carcase on bury are generating soil, underground water and source water pollution, introduction of new preventive system should be considered. In this study, literature survey and case studies to prevent the spreading of virus for infectious disease and second environmental pollution were investigated. The actual experiments using the existing incineration facilities were also performed to ensure the possibilities of safe treatment of carcase. On the other hand, the moving-type incineration are also being developed and its operation manual will be prepared. Among the investigated incinerators, stoker type incinerator was not suitable for the treatment of carcase, however, other incinerators such as fluidized-bed type incinerator, rotary kiln type incinerator ware shown to be suitable. But even for the stoker type incinerator, if the pre-treatment facilities( grinding, crushing) are installed, it will also be a suitable method. The analytical results for air pollutants(including dioxin) emitted from the final exit were all satisfied to the air pollution emission standards.
        107.
        2013.04 KCI 등재 서비스 종료(열람 제한)
        In this study, PCDDs/DFs concentrations in flue gases from 58 crematories and in fly ashes and bottom ashes (mainly bone) from several crematories were measured to grasp the present state of PCDDs/DFs emissions from crematories. The effects of several factors were discussed to prevent PCDDs/DFs emissions from crematories. Total concentration of PCDDs/DFs was ranged from 0.113 to 87.461 ng/Sm3 and toxic equivalent concentration was ranged from 0.019 to 15.347 ng-TEQ/Sm3. As the results obtained in this research, the following measures to reduce PCDDs/DFs emission are recommended for existing crematories: (1) keeping the temperature at < 800oC or < 850oC in main/secondary chambers during a whole cremation, (2) lowering the temperature in the dust collector, (3) installing the high efficiency dust collector and reducing dust concentration to less than 0.02 g/Sm3, and (4) installing the sampling point for monitoring of PCDDs/DFs.
        108.
        2012.08 KCI 등재 서비스 종료(열람 제한)
        눈잣나무는 동북아시아가 주 분포지로 남한에서는 설악산 고산지역에만 제한적으로 분포한다. 본 연구는 설악산 눈잣나무 집단의 분포형태와 특성, 유전다양성 및 공간분포에 따른 유전구조를 파악하였다. 선발된 9개 I-SSR primer에서 총 78개 I-SSR 증폭산물을 얻었으며, 30개의 단형성 증폭산물을 제외한 48개의 증폭산물을 분석에 이용하였다. 조사구(40 m × 70 m)에는 눈잣나무 65개체가 자생하고 있었으며, 채집한 눈잣나무의 위치자료를 바탕으로 군집지수를 계산한 결과 약하게 집중분포(Aggregation Index = 0.871)하고 있음을 확인하였다. 모든 개체에 대하여 I-SSR 유전자형을 비교한 결과, 65개체 중 유전자형이 서로 다른 40개의 genet이 식별되었다. 유전자형 비율(G/N)은 61.5%, 유전자형 다양성(D)은 0.977, 유전자형 균등도(E)는 0.909로 각각 나타났다. Shannon의 다양성지수(I = 0.567)는 적은 개체수와 제한적 분포에도 불구하고 다른 수종들에 비해 비교적 높은 유전다양성을 나타났다. 공간적 자기상관 분석을 실시한 결과 조사지역 내의 눈잣나무 집단은 12 m 이내에서 유전적으로 유사한 군락구조를 갖고 있는 것으로 나타났다. Mantel 검정 결과 유전적 거리와 지리적 거리간에 낮은 상관관계를 나타내 눈잣나무 집단이 초기에 여러 개의 모수에서 형성된 것으로 추정되었다. 본 연구결과 설악산 눈잣나무 집단의 현지외 유전자 보존을 위한 표본추출 전략은 최소 12 m 이상의 거리를 두는 것이 효율적인 것으로 나타났다.
        109.
        2012.02 KCI 등재 서비스 종료(열람 제한)
        To assess parameters of mating system in seed orchard, such as outcrossing rates, number of potential pollen contributors, and degree of pollen contamination, seeds, produced in '77 plot of the Japanese red pine (Pinus densiflora S et Z) seed orchard at Anmyeon island, were collected in 2007 and analysed by nSSR and cpSSR markers. Estimates of outcrossing rates ranged from 91.2 to 100% (mean 97.7%) on the basis of the analysis of cpSSR haplotypes and from 81.6 to 100% (mean 95.3%) on the basis of the analysis of nSSR genotypes. By cross checking of both DNA markers, seeds, presumed to be products of self pollination on the basis of single marker, were confirmed as outcrossed seeds, which resulted in cumulative outcrossing rates of 98.9%. On the basis of pooled cpSSR haplotype of each seed, the number of pollen contributors and paternal contribution rates were estimated as 14.8 and 0.512, respectively. In conclusion, considering pretty high level of outcrossing rates observed in a seed orchard, good genetic potential of the seeds, produced in '77 plot of the seed orchard of Japanese red pines at Anmyeon island, may be guaranteed. Investigated results from the analysis of mating system of Japanese red pines in a '77 plot of the seed orchard may also be expected to provide useful information for the management and establishment of the seed orchard of the progressive generation.
        112.
        2002.04 KCI 등재 서비스 종료(열람 제한)
        For the proposal of Microcystis aeruginosa control technique by coagulants, removal effects of coagulants were carried out using isolated strain and collected water bloom of M. aeruginosa on Downstream of the Nakdong River. Both of purified and field-collected M. aeruginosa were entirely sedimented by the addition of the coagulant Ceramic-Zeolite type Co 100 (1.5 ㎎/ℓ) within 24 hr, but Yellow loess (10 ㎎/ℓ) was less effective for the removal of M. aeruginosa within 24hr. Thus it was concluded that Ceramic-Zeolite type Co 100 was the most effective coagulant.
        114.
        2001.04 KCI 등재 서비스 종료(열람 제한)
        Improvement of water quality and Investigation of bacterial characteristics have been conducted in a pilot plant using biological activated carbon (BAC) in water treatment process at the downstream of the Nakdong River. Most of water control parameters were highly improved after passing through BAC. Approximately 54% of dissolved organic carbon was removed in coal-based BAC process. Bacterial biomass and bacterial production appeared 9.8×108 CFU/g and 7.l㎎-C/㎥·hr in coal-based BAC, respectively. Predominant bacteria species grown in BAC were identified as Pseudomonas, Flavobacterium, Alcaligenes, Acinetobacter and Aeromonas species. Particularly Pseudomonas vesicularis was dominant in both coal-based and coconut-based BACs, while Pseudomonas cepacia was dominant in wood-based BAC.
        115.
        1999.02 KCI 등재 서비스 종료(열람 제한)
        The relationship between primary productivity and changes in water quality was investigated at Mulgum station, a site downstream of the Nakdong River, Korea. Phytoplankton production was characterized by blooms of Microcystis aeruginosa during the summer and Stephanodiscus hantzschii during the winter. Primary production and secondary production by bacterioplankton ranged from 1.5∼53.5㎎·C/ℓ'day and 0.1∼0.3 ㎎·C/ℓ'day, respectively. Distribution of total organic carbon appeared to be highly correlated with phytoplankton biomass, especially during blooms of M. aeruginosa, when particulate organic carbon was 81% of total organic carbon and the main source of organic materials supplied into the water. The correlation coefficient between chlorophyll-a and BOD was 0.86. Thus it was concluded that autochthonous phytoplankton mostly affected the BOD level. Total bacterial numbers were also highly correlated with chlorophyll-a (r2=0.84) and the bacterial community appears to be regulated by phytoplankton biomass in this area.
        6