• Journal of Environmental Science International
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• v.13 no.6
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• pp.571-579
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• 2004

There is a need to improve the efficiency of the existing sanitary treatment facilities, because the effluent standard becomes more stricter and septic sludge increased. Thus, operating processes of sanitary treatment system in M city changed with installation of additional facilities. Process modifications were as follows: Dilution water was added to the next process after primary aeration tank. Some secondary sedimentation sludge was recycled to primary aerator so that most of the organics were stabilized in primary aeration tank under automatic control of dissolved oxygen. The line of effluent from dewatering process flowing to the activated sludge tank was changed to the primary aerator. The primary sedimentation sludge line was linked to a thickener. Polymer was added to the activated sludge tank. The effluent of primary aerator and aerobic digester was recycled from the 5th to the 1st sector. As consequencies of above process modifications, the improvement of removal efficiency was achieved as BOD 54%, COD 42%, SS 61%, T-N 39%, and T-P 12%, respectively.

• Journal of the Korean Dietetic Association
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• v.7 no.1
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• pp.19-27
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• 2001

It is thought that the sanitary perception and hygienic food treatment of food suppliers as the first handlers of foodstuffs are extremely significant for the safe and sanitary management of food in group meal services. So in this study, a survey of 103 food suppliers who provide raw materials for 80 meal services in business places around Busan area was conducted on general matters, participation in sanitation education, sanitary perception, sanitary treatment of foodstuffs, knowledge of sanitation, etc. The results of the survey are as follows: 1. 42.7% of the subjects have worked for the food supply companies for one to five years and the main job of 36.9% of them is delivery service. Food suppliers who handle over two foodstuffs are 6839%. 2. Concerning the participation in sanitation education, 43.7% of the subjects have not experienced any such education, The reason of 23.3% of them for not having the education is that there have been no opportunity for them at all. And 83.5% of them regard the education on hygiene as necessary. 3. In the sanitary perception, 93.1% of the subjects considered the temperature control of the food delivery vehicles as important and 82.5% of them replied on of the leading causes of food poisoning as foodstuffs. 64.0% thought of their knowledge of food sanitation as not very good, but moderate. 4. Concerning sanitary treatment of foodstuffs, 50.5% of delivery vehicles were wearing sanitary uniforms and 24.3% of them washed their hands while supplying food. 5. In the score of hygienic knowledge, the average score of all food suppliers was 60.6 point. In the score of hygienic knowledge on general matters, managing supervisors got 6.31$\pm$1.70. In the score of hygienic knowledge based on the perception of food sanitation, the food suppliers with the experience of sanitation education scored 6.42$\pm$1.93 point and the point was significant(p<0.01), compared with that of the food suppliers without the experience of sanitation education. The food suppliers who answered their knowledge was very good scored the highest point, 8.00$\pm$1.41. The food suppliers who replied that sanitation education was truly necessary recorded the hygienic knowledge score of 6.75$\pm$1.77, significantly(p<0.01) high. In the score of hygienic knowledge on the basis of the practical degree of sanitary handling of food materials, the food suppliers who answered they cleaned their delivery vehicles everyday scored 6.48$\pm$1.93, the food suppliers who answered they sterilized their delivery vehicles everyday scored 6.29$\pm$1.89, the food suppliers who answered they controlled the temperature of their delivery vehicles irregularly scored 6.58$\pm$1.79 and the food suppliers who answered they washed their hands every time when they were working scored 6.86$\pm$2.24, significantly(p<0.05) high in comparison with every item in other factors. And the food suppliers who answered they were wearing sanitary uniforms irregularly while supplying foodstuffs scored the highest point, 6.66$\pm$2.92.

• Journal of environmental and Sanitary engineering
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• v.13 no.2
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• pp.139-146
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• 1998

The characteristics of color and COD removal for dyeing-wastewater using electrochemical reaction were investigated. >From the result, the removal efficiency of color and COD were increased with increase of temperature, decrease of electrode distance, increase of electrolyte concentration and increase of potential and these were obtained above 99%, above 75% within 30 min, individually. Cause of higher COD removal efficiency, it is more suitable that dyeing-wastewater is treated by electrolytic treatment prior to biological treatment. It is concluded that the electrolytic treatment of dyeing-wastewater can be used as the effective and economical method in practical treatment.

• Journal of environmental and Sanitary engineering
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• v.2 no.3 s.3
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• pp.1-4
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• 1987

Since the worldwide energy crises experienced in 1970's, the value of anaerobic wastewater treatment processes has been renewed. In that respect. the characteristics and current developments of anaerobic processes are shortly reviewed in this article.

• Journal of the Korean GEO-environmental Society
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• v.10 no.1
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• pp.15-23
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• 2009

The aim of this study was an evaluation of closed non-sanitary landfill's stabilization degree and a determination of its an optimal reclamation method. In order to evaluate the stabilization degree, physical compositions of landfill wastes in 21 closed non-sanitary landfills were analyzed. There were 4 major items such as cover soils, organics, combustibles and incombustibles. With respect to the results of physical compositions, it was determined that the waste in 9 sampling sites of closed non-sanitary landfills after 10years of the relief time was not fully stabilized. The closed non-sanitary landfills must be reclaimed as soon as possible. The main material in closed non-sanitary landfills was cover soils and the highest content was 89.96%. Otherwise, the contents in sanitary landfills was small and 9.89~11.12%. Therefore, it was evaluated that the recovered soil by sorting transfer treatment could be reused as on-site cover soils of the reclamating non-sanitary landfills and/or constructing materials.

• Journal of environmental and Sanitary engineering
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• v.15 no.1
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• pp.14-24
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• 2000

The water treatment by ozone was performed to remove VOC and organic substances in the multistage ozone contactor. This paper is secondary paper about the theme of ozone treatment since the first paper (Kor. Sanitary J., 15, 1(2000)) publicized, it was compared experimental results with theoretical those which were derived from the mathematical model associated with chemical reactions and mass transfer. Basic designing factors were determined as an optimal conditions for the removal rate of VOCs as follows: ozone input concentration in the contactor was 2mg/L, ozone contact time was 7 min and number of contactor was three-layered.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.20-25
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• 2000

The wastewater treatment for the purpose of water-recycling was performed using Fenton's & ozone's methods. These methods were used to increase the treatment efficiency of textile wastewater and to search for the optimal operating conditions. The optimal conditions by Fenton process were determined so that input amounts of $FeSO_4{\cdot}7H_2O$ and $H_2O_2$ were $7.2mM/{\;}{\ell}$ and $49.0m/{\;}{\ell}$ respectively, treatment by ozone process had 92% removal efficiency at ozone concentration of 9.73g/min and $130mM/{\;}{\ell}$ of $H_2O_2$.

• Journal of the Korean Home Economics Association
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• v.43 no.11 s.213
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• pp.127-140
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• 2005

Sanitary management performance and knowledge of employees in hospital food service was evaluated by survey questionnaire to improve their sanitary management performance, analyse the weak points of sanitary management, and determine more practical and efficient alternatives of sanitation education. For this study, we selected 6 dieticians and 250 employees working in the six general hospitals larger than 400 beds in Gyeonggi and Incheon area. The questionnaire consisted of three parts: general subjects in the nutrition division of hospitals, sanitation education of dieticians, and sanitary management performance and knowledge of employees. The average ratio of HACCP related equipment and facilities of the target hospitals was relatively high at $86.5\%$. The number of sanitation education was 1.99 times/month by regular schedule and 6.47 times/month by occasional schedule. The average dietician's inspection time of cooking was 178.77 minutes/day. The average point of sanitary management performance was 4.62/5.0, showing a relatively high grade. In each region of sanitary management performance, food treatment sanitation was marked with the highest point, at 4.85, fellowed by cleaning and sterilizing sanitation at 4.65, personnel sanitation at 4.61 point and device and utensil sanitation was ranked with the lowest point at 4.53. Sanitary management performance was affected by the number of occasional education which was highest at 6-10times/month. The mean score of sanitary knowledge was 11.17/15.0. The assigned position, type of employment, status, working career and number of occasional education affected the mean score of sanitary knowledge of employees significantly. Sanitary knowledge of employees was highest in the case that occasional education was peformed at 6-10 times/month. There was no correlation between the sanitary management performance and sanitary knowledge of employees. In contrast, there were correlations between sanitary management performance and dietician's inspection time of cooking and number of employees.

• Journal of environmental and Sanitary engineering
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• v.11 no.3
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• pp.37-46
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• 1996

In this study, the effect of pH, Temp, dye concentration, distance of electrode, and the potential on the removal efficiency of dye-wastewater using electrochemical reaction were investigated. Optimum conditions for the electrochemical treatment of dye-wastewater were obtained that pH;7, 8V, electrode distance; 1cm and the reaction time for obtaining above 99% removal efficiency were 10 - 40min at each conditions, From this result, we can determine the instantaneous current efficiency and specific energy consumption, and we can provide the effective data for economical treatment of industrial dye-wastewater.

• Journal of environmental and Sanitary engineering
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• v.23 no.4
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• pp.13-21
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• 2008

With the rise in membrane applications, residuals management has become a growing challenge for membrane system. The primary residuals of MF/UF (microfiltration/ultrafiltration) system results from the wastes generated during backwashing. Many regulatory agencies, utilities, and water process engineers are unfamiliar with the characteristics and methods for treatment and disposal of membrane residuals. Therefore, this study was performed to investigate the backwash residuals water quality from the pressurized system with and without pre-coagulation, and to suggest approaches for the backwash residuals treatment. Pressurized MF system was installed at Guui water intake pumping station and operated with raw water taken from the Han River. We compared performances with and without the recycling backwash residuals at flux conditions, 50 LMH and 90 LMH with and without pre-treatment (coagulation). Based on the results, recycling of backwash residuals in pressurized system with pre-coagulation showed applicability of backwash residuals managements. Moreover, the recovery rate also increased up to over 99%.