• 대한환경공학회지
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• 제28권12호
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• pp.1265-1273
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• 2006

용담댐 저수지에 대하여 목표수질 설정과 오염물질 부하량 추정 및 유량분석을 실시하여 수질의 변화과정을 모의함으로써 환경용량과 오염부하삭감량을 추정하였다. 목표수질은 상수원수 $1{\sim}2$등급, COD $1.0{\sim}3.0$ mg/L와 TP $0.01{\sim}0.03$ mg/L로 설정하고, 용담댐 저수지의 수질모형을 42개 소구획을 가진 WASP5로 구성하고, 보정하여 측정치와 계산치의 상관계수는 BOD 0.73, $PO_4-P$ 0.98이었다. 목표수질 COD 2.0 mg/L와 TP 0.02 mg/L에 대한 환경용량은 연구조건에 따라 BOD $131,880{\sim}4,694$ kg/일, TP $7,855{\sim}167$ kg/일이고, 각 경우의 오염부하 삭감률은 BOD $51{\sim}62%$, TP $47{\sim}67%$로 나타났다. 환경용량은 기존연구보다 작게 추정되었고 삭감부하율은 기존결과들의 중간에 해당하였다. 상수원수 $1{\sim}2$등급의 수질을 연중 달성할 오염부하 삭감률은 기존 연구조건에서 BOD $72{\sim}16%$, TP $78{\sim}36%$이고, 신규 연구조건에서 BOD $81{\sim}44%$, TP $84{\sim}52%$로 나타났다. 기존연구의 삭감량과 비교하면 BOD는 가장 적고 TP는 4개 중 2번째로 적었다. 목표삭감부하량의 소유역별 배분에서 TP는 취수탑 구획에 대한 근접도의 영향이 크게 나타났으나 COD는 별다른 차이가 없었다.

• 대한환경공학회지
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• 제35권1호
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• pp.17-22
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• 2013

본 연구는 조류 개체 수 증가로 pH가 급격하게 상승한 원수가 정수장으로 유입될 때 pH 조정을 위해 사용하는 이산화탄소($CO_2$) 주입이 응집효율 및 용존 알루미늄 농도변화에 미치는 영향을 고찰하였다. 응집제 1 mg/L에 주입에 따른 pH 감소는 LAS -0.0384, PAC -0.0254, A-PAC -0.0201, PACS2 -0.0135로 나타났다. 용존 알루미늄 농도는 pH 7.44에서 0.02 mg/L, pH 7.96에서 0.07 mg/L, pH 8.16에서 0.12 mg/L, pH 8.38에서 0.39 mg/L로 응집공정의 pH 증가에 따라 용존 알루미늄 농도가 증가하는 것으로 나타났다. 여기서 주목할 점은 급속 교반 후 pH 8.0을 초과할 때부터 용존 알루미늄 농도는 급격하게 증가하는 것이다. 그러므로 높은 pH의 원수가 유입되는 정수장에서 알루미늄 농도가 먹는 물 수질 기준 만족하기 위해서는 응집공정의 pH가 7.8 이하로 유지되도록 공정관리가 필요하며, 원수 pH가 8.0 이상 유입되는 경우 이산화탄소($CO_2$) 주입으로 pH를 7.3 내외로 일정하게 유지할 수 있었다. 또한 이산화탄소($CO_2$) 주입으로 응집공정에서 pH를 조정함으로써 탁도 및 응집제 절감, 용존 알루미늄 농도 감소 효과를 확인할 수 있었다.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 Proceedings of KSEH.Minamata Forum
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• pp.103-114
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• 2005

Chlorine disinfection has been used in drinking water supply to disinfect the water-borne microbial disease which may cause to serious human disease. As Chlorination is still the least costly, relatively easy to use, chlorination is the primary means to disinfect portable water supplies and control bacterial growth in the distribution system. However, chlorine also reacts with natural organic matter (NOM), which presents in nearly all water sources, and then produces disinfection by-product (DBps), which may have adverse health effects. Although the existent DBPs have been reported in drinking water supplies, it is not feasible to predict the levels of the various DBPs due to the complex chemistry reaction involved. The objectives of this study were to investigate seasonal variation of DBPs formation and difference of DBPs concentration in the plant to tap water. The average concentration of THMs was 20.04 ${\mu}g/{\ell}$, HAAs 8-15 ${\mu}g/{\ell}$, HANs 2-4.5 ${\mu}g/{\ell}$ respectively. Distant variation of DBPs formation is that THMs concentration increase by 17% at 2 km point from the plant and by 28% at 7 km and HAAs, HANs also increase each by 16%, 32%, at 2 km from the plant and 35%, 56%, at 7 km. DBPs increase in water supply pipe continually. The seasonal occurrence of DBPs is that in May and August DBPs concentration is very high then in March, in May DBPs concentration is highest. The temperature is main factor of DBPs formation, precursor also. Precursor which was accumulated for winter flowed into the raw water by flooding in spring and summer and produced DBPs. Therefore for the supply of secure drinking water, it is required to protect precursor of flowing into raw water and to add to BCAA and DBAA to drinking water standards.

• 한국수산과학회지
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• 제16권2호
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• pp.117-124
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• 1983

Qualify changes of the precooked frozen sardine (Sardinops melanosticta) during frozen storage were investigated by measuring extractable protein, expressible drip, available lysine and lipid oxidation as peroxide value. Fresh sardine was dressed, washed in chilled water, cooked in boiling water to have $55^{\circ}C\;and\;70^{\circ}$ at the center of the body, frozen at $-40^{\circ}C$, and finally stored at $-20^{\circ}C$ for 84 days. The quality factor mentioned above were determined in both ordinary and dark muscle at 14 day intervals through the period of storage. When cooked at $70^{\circ}C$, the changes in expressible drip were less than that of raw and the one cooked at $55^{\circ}C$. In observation of the extractability of muscle protein, no great change in extractable sarcoplasmic protein was observed, the extractable myofibrillar protein, however, showed a tendency to decrease during the period of frozen storage, accompanying the increase of the alkali-soluble protein. That was more excessive in ordinary muscle than dark muscle. Lipid oxidation of dark muscle was faster than that of ordinary muscle. Acid value was not changed, and peroxide value of the samples cooked at $70^{\circ}C\;and\;55^{\circ}$ was higher than that of raw at the early stage of the storage, after 40-50 day storage, it became lower than that of raw muscle.

• 한국식품조리과학회지
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• 제4권2호
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• pp.11-19
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• 1988

밀 단백 분말을 주재료로 한 인조육을 제조할 때 첨가재료의 첨가량이 품질 특성에 영향을 주는 요인을 분석한 결과는 다음과 같다. 1. 첨가 재료의 첨가량에 따른 영향으로 호두는 글루텐 인조육의 색에 가장 크게 영향을 주었으며, 호두 첨가량이 증가함에 따라 경도, 응집성 및 저작성은 감소의 경향을 나타냈고, 탄력성과 보수성은 대체로 증가하였는데, 호두를 30% 첨가할 때 쇠고기의 측정치에 근접하였다. 2. 식용유의 종류와 첨가량 및 흔합 방법은 색, 전단력, 경도 및 저작성에 영향을 주지 않았으나, 응집성은 유의적인 차이를 나타냈다. 3. 소금의 첨가량이 증가하면 경도와 저작성이 증가하였고, 전단력과 보수성에는 영향을 미치지 않았으며, 소금을 2% 첨가한 시료가 경도, 탄력성, 응집성 및 저작성에서 가장 쇠고기의 특성에 근접하였다. 4. 양파의 첨가량이 증가하면 경도와 저작성은 낮아졌고, 색과 응집성은 양파를 10% 첨가하였을 때 가장쇠고기 의 특성 에 근접하였다.

• 상하수도학회지
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• 제20권1호
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• pp.138-146
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• 2006

The characteristics of backwash and concentrate discharges depend upon the quality of the water being treated and the net recovery of the membrane system. This paper is to indicate a design methods on the capacities of residuals treatment facilities in membrane processes for drinking water. We operated a demonstration membrane plant with a recovery rate of 90% for designing G-water treatment plant. We investigated on design parameter (optimum coagulant dosage and surface loading rate etc.) to design efficiently the residuals treatment facilities. The settling test was conducted with 1m columns dosing PACl to kaolin and membrane residuals under the experimental condition that discharge permit was under a 60mg/L. When the quantity of membrane residuals was $1,575m^3/day$, the estimated results for 1st thickener demonstrated the surface loading rate of 14.4m/day, detention time of 5.83hr, available depth of 3.5m.

• 상하수도학회지
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• 제9권4호
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• pp.107-114
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• 1995

The raw drinking water quality is getting worse because of the winter drought and the conventional treatment system is'nt suitable to obtain the satisfied quality of water. So, the advanced water system, BAC(Biological Activated Carbon) process is said to be effective to remove dissolved organics and ammonia nitrogen. In our study, the BAC pilot plant using Nak-dong river water is tested in low temperature. Following results are found from the study. The ammonia nitrogen removal rate of BAC system using wood-based carbon (PICABIOL) was 99% in $6^{\circ}C$ temperature. Chlorine dosage in wood-based BAC effluent was reduced to 67% of that in sand filtered wate. It resulted from the removal of ammonia nitrogen. Also, THM formed by chlorine addition in wood-based BAC effluent was decreased to 65% of that in sand filtered water. In the case of dual-filter, the removal efficiency of ammonia nitrogen was increased 30% more than in conventional sand filter. According to this result, the ammonia nitrogen load to BAC system could be lessened by the use of dual-filter.

• 한국식품조리과학회지
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• 제4권1호
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• pp.9-16
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• 1988

밀단백분말을 주재료로 한 인조육을 제조할 때, 품질특성에 영향을 주는 요인을 분석한 결과는 다음과 같다. 1. 색에 영향을 주는 요인은 호두, 식용유, 소금, 양파, 물, 식용유와 물의 상호작용 및 가열온도와 가열시간이었다. 2. 전단력에는 호두, 양파, 물, 호두와 식용유의 상호작용이 영향을 주는 것으로 나타났다. 3. 경도, 탄력성, 응집성 및 저작성에는 호두, 식용유, 양파, 소금, 물, 호두와 식용유, 식용유와 물의상호작용 및 가열온도가 영향을 주었다. 4. 보수성에는 호두와 물이 영향을 주는 요인이었다.

• 한국축산식품학회지
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• 제35권4호
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• pp.441-448
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• 2015

Blanching beef for use in home meal replacements (HMR) is an important process that determines the final quality of the beef after the cooking process. Thermal pretreatment also minimizes the change in quality during the main cooking process or storage. In this study, beef samples were washed and sliced, then treated by immersion in boiling water (1-10 min), steaming (1-10 min), or pan-frying in oil (30-240 s). The color after each thermal treatment showed higher L* and b* values and lower a* values compared with the raw beef, except for the pan-frying thermal treatment. The total color difference (∆E) and pH value were significantly increased by panfrying (p<0.05). There was no significant difference in the shear force of the beef samples, except for the sample pan-fried for 210 s. The nutritional content of beef was measured as the moisture, protein, fat, and ash contents, which were 69.96, 16.64, 3.49, and 1.13%, respectively, in raw beef. After thermal treatment, the crude protein and fat contents were increased, whereas the moisture and ash contents decreased. The mineral content, including Na, Mg, Fe, and Ca was highest after pan-frying. The heat treatment decreased microorganisms in all the samples. The total bacteria count in raw beef was 4.5-4.7 Log CFU/g, whereas the bacteria count decreased to 2.2-2.8 Log CFU/g after blanching. Thermophilic bacteria, coliform, mold, and yeast not detected in any thermally treated sample.

• 한국물환경학회지
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• 제22권3호
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• pp.521-526
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• 2006

We have studied the possibility of removing Anabaena macrospora by injecting copper sulfate ($CuSO_4{\cdot}5H_2O$) into the raw water of a drinking water purification plant. Anabaena macrospora caused the unpleasant geosmin odor of drinking water in August 2001. The cell break-point of A. macrospora was 0.3 mg/L of $CuSO_4$. We were able to reduce the standing crops of A. macrospora effectively because $CuSO_4$ could break A. macrospora selectively. Because 0.3 mg/L of $CuSO_4$ could break both cells and akinetes, it reduced the possibility of a recurrent problem for them to meet a favorable condition. When $CuSO_4$ was injected in the early growth phase of algae and the mixing intensity was high, A. macrospora could be removed most effectively. The odor caused by A. macrospora was sustained for a while without any sudden change of environmental condition. Therefore, we hope that it could shorten the period of obstacle by injecting the optimal amount of 0.3 mg/L of $CuSO_4$. The water quality, alkalinity, conductivity, hardness and pH didn't changed by the injection of $CuSO_4$.