• 한국환경농학회지
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• 제26권3호
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• pp.204-209
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• 2007

Agricultural area in the vicinity of the ${\triangle}{\triangle}$ smelting factory in Kyeongbuk province, the third largest zinc smelting factory in the world, was contaminated by high concentration of heavy metals. However, the heavy metals source was not yet directly traced and thus, resulted to a conflict between the factory and residents within its vicinity. In order to determine the level of heavy metal contamination in the arable lands located at the north eastern part of the factory, soils were sampled systematically. To find out the major reason for the occurrence of this problem, waters and aerosols were sampled with constant intervals to the upward and downward direction from the factory and were analyzed to find out the heavy metal concentrations. Cadmium (Cd) and zinc (Zn) of the heavy metals were highly accumulated more than the Korean warning criteria (Cd 1.5, Zn 300 mg $kg^{-1}$) with mean values 1.7 and 407 mg $kg^{-1}$, respectively, at the surface soils (0-20 cm), and heavy metal concentration significantly decreased with increasing soil depth In addition, the concentration of both metals slightly decreased with increasing distance from the factory to the surface soils. Cadmium and Zn were detected in the upward stream water with low concentration and concentrations increased significantly in the downstream after passing across the factory. Aerosol samples also showed traces of Cd and Zn which could be attributed to the contamination of the water system and the surface soils. Conclusively, Cd and Zn emitted from the ${\triangle}{\triangle}$ smelting factory moved with the aerosol in the atmosphere and thus, contaminated the agricultural areas and the water system within it vicinity.

• 한국초전도ㆍ저온공학회논문지
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• 제20권2호
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• pp.16-19
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• 2018

Comprehensive utilization of zinc smelting iron slag not only solves environmental problems but also creates huge economic benefits. This study was conducted on the enrichment and recovery of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag by superconducting HGMS technology. Several variables such as slurry flow velocity, slag concentration, magnetic field intensity and the amount of dispersing agent were tested in magnetic separation. In the experiments, obtained optimal magnetic separation parameters were 1.60 T of magnetic flux intensity, 600 mL/min of slurry flow velocity of, 15 g/L of slag concentration of, 0.10 g/L of dispersing agent. Under this condition, the content of ${\alpha}-Fe_2O_3$ was increased from 86.22% to 94.39% that can approach the Chinese national standard requirements (A level) of iron oxide red. It was concluded that using superconducting HGMS technology was an effective method for the purification of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.375-380
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• 2001

MF is a half shaft blast furnace which has been developed at Mitsui Miike Smelter in the 1960’s to treat vertical retort residue. The MF has also been tested for treatment of various recycling materials and wastes. Now various secondaries and wastes (EAF dust, zinc leaching residue, Cu sludge, etc ) are mainly treated. Powder materials are briquetted with reductant before being fed to the furnace. Products are crude zinc oxide, matte, non-hazardous slag and steam. Zinc and lead are recovered in oxide dust, and copper and silver are recovered in matte. The MF can be widely applied to many kinds of materials which contain such non-ferrous metal-valuables. In addition, the improvement in operation and technology has effectively made the unit capacity much larger. The MF now has many advantages for these treatment processes.

• 자원리싸이클링
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• 제1권1호
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• pp.37-43
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• 1992

The submerged injection smelting process was performed to recover Zn and Pb from steel dust throuth vaporization and to investigate the effect of temperature, slag composition, injection time, gas flow rate, etc. on the recoveries of valuable metals. The results show that vaporation rates of zinc and lead increased at higher temperture and higher moral ratio of ferrous to ferric oxides. In the initial stage of submerged injection of nitrogen gas, the molten slags of the dust have high value of molar ratio of $Fe^{2+}$/$Fe^{3+}$ and hence zinc and lead can be effectively recovered.

• 자원리싸이클링
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• 제21권1호
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• pp.3-16
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• 2012

도시광산 재자원화기술의 모듈과 한국의 비철제련 프로세스를 파악하기 위하여 재자원화기술의 전체상과 요소기술, 물리선별, 비철제련 프로세스 및 바람직한 도시광산 처리기술의 단위조작을 밝히고, LS-Nikko동제련(주)과 고려아연(주)의 리싸이클링 프로세스를 탐색하였다. 끝으로 일본의 대표적인 비철제련소인 DOWA Holdings 및 JX Holdings 리싸이클링 프로세스와 한국의 위 두 비철제련소의 리싸이클링 프로세스를 비교검토 하였다.

• 한국대기환경학회지
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• 제26권5호
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• pp.507-516
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• 2010

Stationary combustion sources such as coal-fired power plants, waste incinerators, industrial manufacturing, etc. are recognized as major sources of mercury emissions. Due to rapid economic growth, zinc production in Korea has increased significantly during the last 30 years. Total zinc production in Korea exceeded 739,000 tons in 2008, and Korea is currently the third largest zinc producing country in the world. Previous studies have revealed that zinc smelting has become one of the largest single sectors of total mercury emissions in the World. However, studies on this sector are very limited, and a large gap in the knowledge regarding emissions from this sector needs to be bridged. In this paper, Hg emission measurements were performed to develop emission factors from zinc smelting process. Stack sampling and analysis were carried out utilizing the Ontario Hydro method and US EPA method 101A. Preliminary data showed that $Hg^0$ concentrations in the flue gas ranged from 4.56 to $9.90\;{\mu}g/m^3$ with an average of $6.40\;{\mu}g/m^3$, Hg(p) concentrations ranged from 0.03 to $0.09\;{\mu}g/m^3$ with an average of $0.04\;{\mu}g/m^3$, and RGM concentrations ranged from 0.23 to $1.17\;{\mu}g/m^3$ with an average of $6.40\;{\mu}g/m^3$. To date, emission factors of 7.5~8.0 g/ton for Europe, North America and Australia, and of 20 or 25 g/ton for Africa, Asia and South America are widely accepted by researchers. In this study, Hg emission factors were estimated using the data measured at the commercial facilities as emissions per ton of zinc product. Emission factors for mercury from zinc smelting pross ranged from 4.32 to 12.96 mg/ton with an average of 8.31 mg/ton. The emission factors that we obtained in this study are relatively low, considering Hg contents in the zinc ores and control technology in use. However, as these values are estimated by limited data of single measurement of each, the emission factor and total emission amount must be updated in future.

• 한국물환경학회지
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• 제26권5호
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• pp.768-774
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• 2010

This study was conducted to provide a technical solution to treat effectively perchlorate from inorganic wastewater of zinc smelting. Despite an inhibition dissolved inorganic substances in the wastewater discharged from zinc smelting has demonstrated with the activity of microbes, biological treatment technology could reduce perchlorate to a satisfactory level under such stressful conditions. It was found that either conductivity or $SO{_4}^{2-}$ concentration of the wastewater was able to be used as the adequate index and the values were $2,450{\mu}S/cm$ and 1,200 ppm respectively. When $SO{_4}^{2-}$ increased from 0 to 16,000 ppm (conductivity : $428{\rightarrow}24,800{\mu}S/cm$), perchlorate biodegradation rate was reduced due to 1/10 times from 0.0365 to 0.0033/h, however, most of perchlorate was removed under the condition of hydraulic retention time (HRT) at 0.5day and mixed liquor volatile suspended solid (MLVSS) at 2,000 ~ 3,000 ppm.

• 한국환경농학회지
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• 제26권3호
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• pp.210-216
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• 2007

The cadmium (Cd) and zinc (Zn) contamination of soils and cultivated crop plants by zinc smelting activities was studied. In the study area of the vicinity of ${\triangle}{\triangle}$ zinc smelting factory in Korea, soils and corn plants were sampled at corn harvesting stage and analyzed Cd and Zn concentration as well as Cd and Zn fraction and chemical properties in soils. At 600 m radius of studied area, Cd and Zn were highly accumulated in the surface soils (0 - 20 cm) showed greater than the Korean warning criteria (Cd 1.5, Zn 300 mg $kg^{-1}$) with corresponding values 1.7 and 407 mg $kg^{-1}$, respectively. The leaf part gave higher Cd concentration with the corresponding value of 9.5 mg $kg^{-1}$ as compared to the stem and grains pare (1.6 and 0.18 mg $kg^{-1}$), respectively. Higher Zn concentration was also obtained from the leaf part of the corn plant which gave the value of 1,733 mg $kg^{-1}$. The stem and grain part gave corresponding values of 547 and 61 mg $kg^{-1}$. The order of the mean Cd concentration in fractions is F3 (oxidizable fraction) > F2 (reducible fraction) > F4 (residual fraction) > F1 (exchangeable + acidic fraction). A highly positive correlation is observed between F2 and concentration of Cd and Zn in both plant pare, leaf and grain. Highly positive correlations are shown in the pH exchangeable Ca and Mg, and CEC when correlated with Cd and Zn bound to F4 fractions. To reduce Cd and Zn uptake by corn plant in an arable land heavily contaminated with Cd and Zn as affected by smelting factory, an efficient and effective soil management to increase soil pH and CEC is thus recommended.

• 자원리싸이클링
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• 제7권2호
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• pp.39-45
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• 1998

LD 제강 더스트를 제철원료로 LD 전로 제강 슬래그를 용제로 하고 폐타이어에 의해 제조한 건류탄을 환원제로 사용하여 반사로에서 환원 실험하여 배합비, 온도 및 반응시간 변화에 따른 환원율 및 철 회수율의 영향을 조사하여 다음과 같은 결과를 얻을 수 있었다. 1) $1300^{\circ}C$에서 1시간 동안 환원실험한 결과 탈아연율(removal rate of zinc)이 97%이상이며 잔사중의 Zn은 0.1~0.2%이었다. 2)페렛트 중에 LD 스래그 15~20%, 폐타이어 건류탄 4.1~6.7% 함유된 시료를 대기압, $1350^{\circ}C$에서 3시간동안 환원실험한 결과 선철의 회수율은 89.3~92%이었다. 3)환원제련시에 집진장치에서 회수한 더스튼 Zn 60%의 조산화아연이었다. 4) 회수한 선철의 성분은 Fe 96%, C 1.6%, P 0.08%, S 0.05%이었다. 5) 환원시에 생성한 슬래그의 조성은 $Ca_2Al_2SiO_7$, 8CaO $5SiO_2$ 및 $Na_3Ca_6(PO_4)_5$가 확인되었다.

• 자원리싸이클링
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• 제11권4호
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• pp.37-43
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• 2002

전기로 분진의 유해성을 제거하고 인공자원으로써의 가치를 활용하기 위하여 연구되고 있는 고온용융법을 이용한 전기로 분진의 처리공정에 있어서 유가금속 특히 아연의 환원 거동에 관한 연구를 속도론적인 측면에서 수행하였다. 전기로 분진의 구성 성분인 ZnO와 Franklinte의 환원 반응이 CO gas의 분압에 대하여 1차 반응인 chemical reaction에 의해 지배를 받음을 확인 할 수 있었다. ZnO와 Franklinite의 CO 가스에 의한 환원 반응에 있어서 활성화 에너지는 각각 44.95 kcal/mol, 4.9546 kcal/mol로 나타나 화학반응 단계가 전체 반응의 율속 단계임을 알 수 있었다.