• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 1998.11a
• /
• pp.114-118
• /
• 1998

농촌지역인 공주시 유구읍 명곡리 지역의 천부지하수와 먹는 샘물 공장의 취수정 심부 지하수을 대상으로 지화학적 특성을 밝히고, 물-암석 상호반응과 오염물질 유입에 대해서 토의하였다. 천부 지하수의 화학적 유형은 Ca-HCO$_3$형에서 Ca-Cl(SO$_4$)형으로 전반적으로 약산성화 되어있고, $K^{＋}$, Cl$^{-}$, NO$_3$$^{-}$오염이 상당히 진행되어 70 %이상이 음용수로 불가능한 상태이다. 군집방법에 의하면 신선한 물과 오염된 물사이에 뚜렷한 경향의 차이를 보인다. 천부지하수의 주요 오염원은 각가정에 있는 재래식 화장식, 생활하수, 가축의 축사, 비료등으로 보인다. 심부지하수는 알카리성의 Na-HCO$_3$형에서 Na(Ca)-HCO$_3$형의 화학적 유형이며, 2 TU 이하의 삼중수소 함량으로 1950년대 이전에 함양된 비교적 오랜 물-암석 상호반을 거친 물로 판단된다. 반면 천부형 지하수는 1950년대 이후에 충전된 상당히 젊은 연령의 지하수로 보인다. $^{18}$ O/$^{16}$ O, D/H 환경동위원소 조성값으로 볼 때 심부지하수의 함양지역은 고도의 효과를 보인다. 이 연구결과는 농촌지역의 지하수 수질 오염에 대한 하나의 사례연구로 향후 전국을 대상으로 한 농어촌지역의 지하수 오염연구에 기본방향을 제시하는데 의의 가 있을 것이다.

• Journal of Radiation Protection and Research
• /
• v.39 no.1
• /
• pp.7-13
• /
• 2014

Phosphate rock, phosphogypsum, and products in phosphate processing facility contain naturally occurring radioactive materials (NORM). Therefore, they may give rise to enhanced radiation dose to workers due to inhalation of airborne particulates. Internal dose due to particle inhalation varies depending on particle properties. The objective of the present study was to characterize particle properties at the largest phosphate processing facility in Korea. A cascade impactor was employed to sample airborne particulates at various processing areas in the plant. The collected samples were used for characterization of particle size distribution, particle concentration in the air, and shape analysis. Aerodynamic diameters of airborne particulates ranged 0.03-100 ${\mu}m$ with the highest concentration at the particle size range of 4.7-5.8 ${\mu}m$ (geometric mean = 5.22 ${\mu}m$) or 5.8-9.0 ${\mu}m$ (geometric mean = 7.22 ${\mu}m$). Particle concentrations in the air varied widely by sampling area up to more than two orders of magnitude. The large variation resulted from the variability of mechanical operations and building ventilations. The airborne particulates appeared as spheroids or rough spherical fragments across all sampling areas and sampled size intervals. Average mass densities of phosphate rocks, phosphogypsums, and fertilizers were 3.1-3.4, 2.1-2.6, and 1.7 $gcm^{-3}$, respectively. Radioactivity concentration of uranium series in phosphate rocks varied with country of origin, ranging 94-866 $Bqkg^{-1}$. Among the uranium series, uranium was mostly concentrated on products, including phosphoric acid or fertilizers whereas radium was concentrated on byproducts or phosphogypsum. No significant radioactivity of $^{226}Ra$ and $^{228}Ra$ were found in fertilizer. However, $^{40}K$ concentration in fertilizer was up to 5,000 Bq $g^{-1}$. The database established in this study can be used for the accurate risk assessment of workers due to inhalation of airborne particles containing NORM. In addition, the findings can be used as a basic data for development of safety standard and guide and for practical radiation safety management at the facility.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.13 no.3
• /
• pp.82-88
• /
• 2005

This study was carried out to investigate on the change of NaCl content during the food waste composting and on the safety of food waste compost(FWC) manufactured by the non-stirrer sealed fermenter. Plant culture test with pepper crop was also performed to see the effect of FWC, which was produced by the G co. ltd., on the growth of peper and migration of NaCl in soil. The culture test was performed at the farmland in Chungnam National University. The results were as follows; the NaCl content was gradually accumulated during food waste composting process, probably through water evaporation. Sodium concentration was, however, remarkably decreased at the final stage due to the desalting effect by water which was concentrated on the ceil of the fermentor. The analysis of chemical properties and humidity parameters on the food waste compost revealed that the product is quite a good qualified one. More than 0.5 tons of FWC application on red pepper cultivation caused diminished effect on the yield and the accumulation of salts on soil.

• Journal of Preventive Medicine and Public Health
• /
• v.7 no.2
• /
• pp.319-325
• /
• 1974

A study on the status of sickness and medical care of insured and non-insured groups of employee and his family in Naju fertilizer company, in the year of 1973, was carried out. The results obtained are as follows: 1. 66.8% of all employee was subscribed in this medical insurance program. No woman employee was subscribed and the rate of subscription was increased from 16.1% to 92.0% by age increases. 2. Also, as of period of service, the rate of subscription was increased from 11.3% to 89.4% by the period gets longer. 3. Employee who reside within boundary of the company (76.2%) subscribed more than that whom reside outside boundary (63.9%). 4. Rate of subscription was also indreased by family size becomes larger. In case of single, it was only 19.6% but in the case of family size became more than 6, it increased to 87.4%, 5. As of amount of monthly income, although no one had subscribed those who get less than 30,000 won a month. Subscriber, increased by monthly income get greater. 6. Subscribed family reside within company boundary utilized hospital 35.5 times a year whereas non-subscribed family reside within these utilized 12.5 times. And, subscribed family reside outside boundary utilized hospital 32.2 times a year and non-subscribed family utilized 9.6 times. Regardless of resident area, family who subscribed to this program utilized hospital more often than non-subscribed family. 7. The utilization of the hospital became gradually frequent from 15.6 times to 36.5 times per family by family size became larger. but in non-subscribed group, although it was increased from 8.3 times to 16.5 times per family, it was droped to the least 6.9 times at 2 person family. 8. 17,496 hospital visits were made by all employee and his family in the year 1973. 86.9% of them was made by subscribed group and the rest (13.1%) was made by non-subscribed group. Observing of the type of these sickness by the classification of WHO, only three types of VII (26.7%), XVII (25.0%) and IX(19.3%) were made more often by non-subscribed group while the others were made more by subscribed group. 9. Anual average medical expenditure per family was 13,098.9 won for subscribed family while it was 3,076.1 won for non-subscribed family. 10. Anual average hospital visits per capita was 6.5 times for subscribed groups and 3.4 times for non-subscribed group. Anual average medical expenditure per capita was 2,580.8 won for subscribed group while it was 1,061.0 won for non-subscribed one.

• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.6
• /
• pp.453-462
• /
• 2000

This study was carried out to know the effect of urea addition for composting of paper mill sludge(PMS). For the purpose. PMSs containing 0%, 1.5%, 3%, and 6% urea were composted at aerated static pile(ASP) for about 80day periods. During the composting, the basic physical, chemical, and biological parameters such as temperature, color. C/N ratio, cation exchange capacity, and phytotoxic test were investigated. From the measurement of the parameters, 0~3% urea-containing PMS except for 6% urea-containing PMS showed to be normally stabilized. Thus among these treatments, 0% and 3% urea-containing PMS were applied at agitated bed system(ABS), a pilot plant of a large scale, to evaluate the possibility of practical use. Considering to the changes of the parameters investigated during composting in ASP and ABS, PMS showed to be successfully stabilized in the two facilities. However, when composted with PMS and urea, even the final PMS compost stabilized for a period enough brought out the bright grayish color. So it may be necessary to add a subsidiary amendments such as animal manure to form brown-colored products.

• Korean Journal of Soil Science and Fertilizer
• /
• v.31 no.1
• /
• pp.39-45
• /
• 1998

As a basic research for developing a sludge application technique in forestry, this study was conducted to investigage a reasonable amount and period of sludge to be applied onto forest nursery of Acer palmatum Thunb. The paper mill sludge was used for the study, and ammonium nitrate was treated to some of them to reduce the C/N ratio lower than 40. The maximum amount of applied sludge was 7ton/ha/year, and they were spread on spring and on late summer. The sludge application did not stimulate early growth of the trees during a year. Since there was no significant changes in soil chemical properties, the amount of applied sludge was thought to be too little to result in a significant role for tree growth. However, the soil water showed significant increase of Cu when the activated sludges were applied during late summer. Thus, the time of application need to be determined cautiously with considering the risk of ground water contamination. In conclusion, if we set a goal from the view point of long-term concept such as forest productivity rather than to get a short-term product, the uncomposted sludge in small amount during growing season might be considered to be applied on forest nursery.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2017.04a
• /
• pp.119-119
• /
• 2017

부레옥잠은 대량 재배 및 수확이 가능한 수질정화용 식물로 생활하수, 축산폐수, 공장폐수 등의 수질정화 기능이 뛰어나고, 수확물은 건조 및 발효과정을 거쳐 가축 사료, 유기질 비료, 버섯 배지로 사용이 가능하고, 별도의 공업적 처리를 거치면 고부가가치의 바이오 연료, 연소용 연료로 사용이 가능한 친환경 농업 생산물로 본 연구에서는 부레옥잠의 고형연료 제조를 위한 수면에서 수확장치 개발을 위한 견인 특성을 파악하고 장치개발 가능성을 파악하고자 하였다. 부력구조물 부력, 부레옥잠 견인력, 부력을 측정하기 위한 실험 장치를 제작하여 부레옥잠 중량, 견인방식, 견인속도에 따른 견인력을 측정하였고, 경남 거제시에 위치한 저수지에서 실제 견인실험을 수행하였다. 실험결과 견인중량 및 견인 속도가 증가할수록 견인력은 증가하였으며 인력으로 부레옥잠을 견인하는 경우 부레옥잠 중량당 견인력은 약 $0.9{\sim}1.39kg_f$로 나타났으며 이는 향 후 부레옥잠 견인장치를 설계할 경우 부레옥잠 견인중량에 따른 견인력 산정 시 참고 자료로 매우 유용하게 활용 가능할 것으로 판단되었다. 저수지에서 견인실험 결과 견인속도 증가에 따른 유속저항으로 경운기에 의한 견인작업은 불가능하였으며 인력에 위한 견인 실험결과 부레옥잠 단위중량당 견인력은 견인바 3 m의 경우 1.5 ~ 2.6 N/kg, 견인바 6 m의 경우 2.1 ~ 5.4 N/kg로 비교적 크기로 나타났으나, 견인용 바에 따른 요인을 고려한 경우는 0.36 ~ 0.91 N/(kg-m)로 비교적 일정한 값을 보였다. 견인용 바 6 m, 무부하에서 인력과 경운기로 견인하는 경우 견인력은 39.24 N, 153.03 N으로 인력으로 견인하는 경우가 견인력이 작게 측정되었음. 이는 속도증가에 따라 물의 저항력이 증가함으로 나타난 결과로 부레옥잠 견인 시 견인속도는 0.36 m/s가 가장 적합한 것으로 판단되었다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.05b
• /
• pp.1234-1238
• /
• 2005

우리나라의 수질오염에 대한 규제는 주로 호소 및 하천의 수질을 향상시키기 위하여 하수 및 공장폐수 등 점오염원을 중심으로 관리되어 왔으나 강우와 함께 대량 유출된 비점오염원은 수용하천의 자정능력을 감소시키고 있고 이로 인해 하천과 호소의 수질은 향상되지 못하고 있다. 또한, 농촌지역에서 배출되는 비점오염원은 정확한 기작의 분석이 안 되고 있으며, 비료$\cdot$농약의 사용 증가에 따라 영양염 및 유해물질에 의한 수질오염의 영향이 증가되고 있는 실정이다. 본 연구는 농촌지역의 강우-유출로 인한 비점오염물질의 유출특성 및 배출부하량을 조사하기 위하여 영산강권역의 외남천을 대상으로 조사하였다. 대상 유역의 토지용도 구분은 (1)논지역, (2)밭지역, (3)산지지역, (4)농촌주거지역, (5)복합지역(논, 산지)으로 구분하였다. 시료의 채취는 강우시 5회에 걸쳐 조사하였으며, 2L 용량의 무균채수병에 채취한 후, 아이스박스에 $4^{\circ}C$이하로 보관하여 24시간 이내로 실험실에 운반하여 실험하였으며, 매회 시료 채취 주기는 강우유출이 발생하기 전부터 강우 종료 후 유출량 변화가 없을 때까지 $9\~12$단계로 세분하여 유출량과 pH, DO, BOD, COD, SS, T-N, T-P의 농도를 측정하였다. 본 연구에서 조사한 결과 토지이용별 비점오염원의 SMC를 살펴보면 BOD의 SMC는 $4.38\~11.02mg/{\ell}$, COD의 SMC는 $7.07\~23.99mg/{\ell}$, T-N은 $1.57\~5.20mg/{\ell}$, T-P는 $0.11\~0.274mg/{\ell}$의 범위를 갖는 것으로 나타났으며, 전반적으로 논 지역에서 비교적 높게 나타났는데 이는 농작물의 경작에 따른 시비법의 영향으로 판단된다. 또한, 비점오염원의 유출특성을 보면 전반적으로 초기 오염물질 유출특성 갖는 것으로 나타났다.

• Journal of the Korea Concrete Institute
• /
• v.21 no.6
• /
• pp.729-735
• /
• 2009

In this study, it is experimentally verified a feasibility of the wasted phosphogypsum ($CaSO_4/H_2O$) that is a byproduct from the phosphoric acid process of manufacturing fertilizers can be applied as an admixture in slag cement. For the test, phosphogypsum is modified as dihydrate, hemihydrate, type III anhydrite, and type II anhydrite, and then chemical characteristics and mechanical properties of various slag cements containing above mentioned gypsum materials were analyzed. The test results show that the gypsum made at high temperature has better quality with decrease of water-soluble phosphoric acid ($S-P_2O_5$) which has an effect on the quality of cement. And type II anhydrite shows superior quality in terms of drying shrinkage and the compressive strength of cement paste with hemihydrate at 56 days is higher than other gypsum material.

• Journal of Soil and Groundwater Environment
• /
• v.14 no.2
• /
• pp.1-9
• /
• 2009

This study was objected to identify the effect on water quality and contamination by non-agricultural facilities in 'A' reservoir watershed located in OO city, Kyounggi-do, Korea. Ground- and stream water samples showed (Na+K)-Cl, Ca(Cl, SO$_4$) and Ca-Cl type in an illegally discharging area of sewage and a densely industrial area indicating water contamination. Stream water of an illegally discharging area of sewage had high COD, T-N and T-P. In this area, direct incoming of sewage into stream water was induced ground water system by well pumping, and it made a progress of ground water contaminations with those components. Groundwater of a densely industrial area showed high concentrations of T-N, NO$_3$N. From a nitrogen isotope analysis, stream water of an illegally discharging area of sewage has ${\delta}^{15}N-NO_3$values of 0.7%0 was strongly affected by nitrogen originated from agrochemicals, and a densely industrial area of 19.7%0 from septic system. Ground- and stream water of a livestock fanning area were contaminated with NH$_3$-N and Mn, which was affected by intensive livestock facilities. SAR-conductivity plot indicates the water does not pose either alkalinity or salinity hazard for irrigation. COD, T-N, T-P, NO$3$-N, NH$_3$N and Mn concentrations from contaminated areas were diminished by mixing with 'A' reservoir water. There were no water contaminations in silver towns, vacationlands around reservoir and golf links. Consequently, it should be made a plan of systematic managements for past and- present possible contaminants and sewage systems in preventing water contamination by non-agricultural facilities.