경상북도지역 학교지하수 및 정수기통과수의 수질특성에 관한 연구

김숙찬 ( Suk Chan Kim ),배헌균 ( Hun Kyun Bae ) 한국환경과학회 2011 한국환경과학회지 Vol.20 No.5

This study characterized water quality of groundwater and purified water used for drinking water in 30 schools in Gyeongsangbukdo Province. The results of the study showed that 43% of groundwater and 45% of purified water were not suitable for drinking. Among them, microbial contaminations were the most serious problem. In raw groundwater, the exceeding rates of total colony counts was the highest in August (53.6%). Purified water samples showed higher rate of exceeding drinking water standard for total colony counts while showing lower rate of exceeding drinking water standard for total coliforms and fecal coliforms in March and August. Overall, proper managements for microbial contaminations are required for both groundwater and purified water. Furthermore, special attention should toward students not to drink water when groundwater or purified water exceeds the drinking water quality standard.

Occurrence and exposure assessment of organophosphate flame retardants (OPFRs) through the consumption of drinking water in Korea

Lee, S.,Jeong, W.,Kannan, K.,Moon, H.B. Pergamon Press 2016 Water research Vol.103 No.-

Organophosphate flame retardants (OPFRs) have been widely used as flame retardants and plasticizers in commercial products. Limited data are available on the occurrence and exposure of OPFRs via drinking water consumption. In this study, 127 drinking water samples were collected from tap water, purified water (tap water that is passed through in-house filters) and bottled water from major cities in Korea in 2014. The total concentrations of OPFRs (ΣOPFR) in all of the samples ranged from below the method detection limit (MDL) to 1660 (median: 48.7) ng/L. The predominant OPFR compounds in drinking water were tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroethyl) phosphate (TCPP), and tris(2-butoxyethyl) phosphate (TBEP). Significant differences were observed in the levels of TCPP, TBEP and ΣOPFR among various types of drinking water. TCPP is introduced in the drinking water during the water purification process. Regional differences existed in the levels and patterns of OPFRs in water samples, which indicated the existence of diverse sources of these contaminants. Purified water was a significant contributor to the total OPFR intake by humans. The estimated daily intake of OPFRs was lower than the tentative oral reference dose (RfD) values. In comparison with exposure of OPFRs via dust ingestion, water consumption was a significant source of chlorinated PFRs (99% for TCEP and 34% for TCPP to the total intakes) for Koreans.

이온수기 필터(pH)의 안정화 성능평가

남상엽(Sangyep Nam),권윤중(Yunjung Kwon) 대한전자공학회 2015 전자공학회논문지 Vol.52 No.3

Evaluation of Microbiological Contamination of Water Purifiers at Two Universities in Chungcheong Region

윤진영 대한의생명과학회 2023 Biomedical Science Letters Vol.29 No.4

The purpose of this study is to investigate microbial contamination in water purifiers from two universities (A and B) in Chungcheong region and to evaluate about the harmfulness of the isolated bacteria to the human. The degree of microbiological contamination of six water purifiers at university A was investigated three times from July 2018 to September 2019, and nine water purifiers at university B were investigated in 2023. The isolated bacteria were biochemically identified using an API kit and Vitek-2 system, and then the bacteria were identified to the species level using MALDI-TOF MS. In addition, the possibility of human infection of the isolated bacteria was evaluated through a literature search. In July 2018 and September 2019, the number of bacteria isolated inside the faucet was below the acceptable standard for hot water, but exceed for cold water in all water purifiers. In January and September 2019, bacteria exceeding the acceptable standards were isolated nine times from the cold water of six water purifies (a total of 12 water purifiers). Bacteria identified by MALDI-TOF MS included anaerobic bacteria (Clostridium novyi, Clostridium themopalmarium etc.), Gram-positive bacilli (Microbacterium testaceum, Arthrobacter woluwensis etc.), and Gramnegative bacilli (Acinetobacter nosocomialis, Comamonas kerstersii etc.), which are difficult identify by biochemical methods. In conclusion, bacteria exceeding the acceptable standard were isolated from the cold water of most of the water purifiers. Most of the isolated bacteria were low-pathogenic bacteria from natural environment, but opportunistic bacteria that can cause infection in humans were also isolated from some water purifiers.

단보 : 가정용 정수기 정수효과 실태조사

김난희 ( Nan Hee Kim ),위환 ( Whan Wi ),조광운 ( Gwang Woon Jo ),이윤국 ( Youn Goog Lee ),윤상훈 ( Sang Hoon Yoon ),강영주 ( Yeong Ju Kang ),김은선 ( Eun Sun Kim ),서광엽 ( Gwang Yeob Seo ) 한국환경분석학회 2013 환경분석과 독성보건 Vol.16 No.2

The analysis of raw water and purified water from 105 social welfare organizations in Gwangju was performed to find out the purification effect of water purifiers in use. In the study, 105 purified water samples and corresponding raw water samples (95 from tap water, 10 from groundwater) were analyzed. Forty six inspection items of drinking water standard and main minerals (Ca2+, Mg2+, K+, Na+) were analyzed for groundwater and 28 items such as heavy metals, microorganisms, disinfection by-products, aesthetic materials were analyzed for tap water. When the concentration of each item in purified water showed lower than that of raw water, we expressed the results as the positive(+) effect and vice verse, negative(-) effect. The results of the purification effect of water purifier using tap water and groundwater were presented (+) effect 39.6% and (-) effect 28.0%, (+) effect 39.1% and (-) effect 30.1%, respectively.

원저 : 가정용 정수기의 미생물학적 안전성 평가

손성원 ( Seong Won Sohn ),장원우 ( Won Won Jang ),윤성환 ( Sung Hwan Yoon ),오태권 ( Tae Kweon Oh ),김영주 ( Young Ju Kim ),임윤규 ( Yoon Kyu Lim ) 한국수의공중보건학회 2010 예방수의학회지 Vol.34 No.4

A water purifiers for home-use has been popularly used as increasing distrust of the drinking tap water in views of safety. Besides, chlorination of drinking water can produce trihalomethanes known as a carcinogens. In general, a water purifier is known to remove risk factors such as infectious microorganisms, harmful chemicals and heavy metals. We compared the change of water components before and after purification by a water purifier and evaluated the results whether this purification system is reliable or not for safety of drinking water. The samples of water from 11 sites at the campus of Jeju National University were examined by physicochemical analyses, including concentration of sodium, potassium, chloride, residual chlorine, boron, nitrate nitrogen, sulfur, hexavalent chromium, copper, iron, aluminium, silicon, selenium, vanadium, manganese, molybdenum, nickel, arsenic, antimony, zinc, cadmium, lead, strontium. Microbiological analysis was performed by counting mesophilic bacterial colonies. Almost of all the physicochemical components after purification were shown to decrease tendency of their concentrations but not significantly differenty except that of residual chlorine. Mesophilic bacterial counts after purification were shown to increase when compared to those of tap water. All the tap water was met the acceptance of requirement of drinking water, but samples of the water after purification were failed (4 from 11). After draining generous amount of water from a purifier, bacterial counts were observed to show a decreased tendency. Bacterial colonies were not detected when the concentration of residual chlorine was higher than 0.2 ppm. Although seasonal factors and maintenance condition were not concerned in this study, higher bacterial counts in purified water could cause some problems in using water purifier for home-use. Considering the results obtained, regular maintenance and care including filter change and sterilizing the reservoir are absolutely required. A further study is required to examine where the bacteria are coming from.

고용량 방사성옥소 치료병실의 오.폐수 저감화를 위한 연구

류재광,정우영,신상기,조시만,Ryu, Jae-Kwang,Jung, Woo-Young,Shin, Sang-Ki,Cho, Shee-Man 대한핵의학기술학회 2008 핵의학 기술 Vol.12 No.1

목적: 방사성옥소 치료병실로부터 발생한 오 폐수는 반드시 전용 정화조에서 일정시간 자연 감쇄(decay)시켜 수중 방사능 농도치가 $8.1{\times}10^{-13}$ Ci/ml 이하가 될 때에만 비로소 방류를 하여야 한다. 현재까지 서울아산병원에서는 60 ton 용량의 전용정화조 3개를 구비하여 운영하고 있었지만 2005년 10월부터 방사성옥소 치료병실을 2병상에서 4병상으로 증설 운영함에 따라 급격히 늘어난 방사성 오.폐수량으로 인하여 본원의 정화조 용량으로는 충분한 감쇄(약 125일 이상)여력이 부족하게 되었다. 따라서 본 연구에서는 치료병실 정화조의 오 폐수 유입유량에 기여하는 원인 및 요인들을 밝혀내어 합리적인 개선 조치를 함으로써 정화조 용량 부족 문제를 해결하여 1차적으로는 엄청난 병원의 경제적 손실을 유발시키는 새로운 정화조의 증설을 피하고 방사성 물질의 인위적 배출로 인한 사회적 문제 유발에 따른 대형의료기관의 신뢰도 추락의 예방에 큰 목적이 있다. 대상 및 방법: 2006년 1월부터 10월까지 고용량 옥소 치료 환자 중 150~200 mCi 이상을 투여 받고 2박3일간 입원치료를 하는 환자 402명을 대상으로, 환자 1인당 평균 물 사용량 (변기사용량, 샤워량, 세면량, 기타 등등)을 측정하였으며, 본원의 정화조 60 ton 3개의 만수 후 배출까지의 감쇄 기간을 측정하였다. 또한 본원의 치료 업무 절차를 단계별로 분석하여 정화조 유입유량의 증가 요인을 찾아보았다. 결과: 다음과 원인에 대한 개선을 통하여 본원의 방사성 오 폐수 보관일수를 정화조 1개당 84일에서 2005년 12월말 현재 약 130일로 증가시킬 수 있었다. (1) 기존 변기의 과다한물 소모량 개선 $\rightarrow$ 절수형 변기로 교체 (2) 불필요한 샤워 및 세탁 방지 $\rightarrow$ 샤워 노즐 사용 자제 및 세면대 이용 교육 (3) 치료기간 중 잦은 배뇨를 유발하는 이뇨제 복용 중지 (4) 수분 섭취량과 퇴원시 체내 잔류선량과의 상관관계 분석 (5) 입실 후 치료 전까지의 대기시간에는 외부 화장실 사용 교육 (6) 정화조 만수위 용량 한계치를 최대 85%에서 90%로 증대 운용 결론: 근래에 들어 급격하게 증가된 갑상선질환 관련 환자로 인하여 전국적으로 거의 모든 의료기관에서 방사성옥소치료의 대기일 수가 크게 증가되고 있다. 이러한 시점에 발생된 방사성 오 폐수 관련 문제는 비단 어느 한 의료기관의 문제가 아닌 관련 우리 모두가 해결해야 하는 큰 과제임에 틀림 없을 것이다. 따라서 본 개선 활동은 그 시작을 알리는 신호탄이 될 것이라 생각되며 방사성 치료병실을 운영하고 있는 타 의료기관에서도 이와 관련된 유사상황이 발생된다면 합리적인 정화조운영의 모델방안으로 제시 될 수 있을 것으로 기대된다. Purpose: In general, We discharged radioactive wastewater and sewages less than $8.1{\times}10^{-13}$ Ci/ml in a exclusive water-purifier tank. Our hospital operating three exclusive water-purifier tank for radioactive wastewater and sewages of 60 tons capacity respectively. In order to meet the criteria it need a enough decay more than 125 days per each exclusive tank. However, recently we fell into the serious situation that decay period was decreased remarkably, owing to the wastewater amount increased rapidly by enlarge the therapy ward. For that reason, in this article, I'd like to say the way that reducing of radioactive wastewater and sewages rationally. Materials and Methods: From January, 2006 to October, four hundred and two cases were analyzed. They were all hospitalized during 3 days and 2 nights. We calculated the average amount of water used (include toilet water used, shower water used, washstand water used, $\cdots$), each exclusive water-purifier tank's decay period, as well as try to search the increased factors about water-purifier tank inflow flux by re-analysis of the procedure of radioisotope therapy step by step. Results: We could increase each exclusive water-purifier tank's decay period from 84 days to 130 days through the improvement about following cause: (1) Improvement of conventional toilet stool for excessive water waste $\rightarrow$ Replacement of water saving style toilet stool (2) Prevention of unnecessary shower and wash (3) Stop the diuretics taking during hospitalization (4) Analysis of relationship between water intakes and residual dose of body (5) Education about outside toilet utilization before the administration (6) Changed each water-purifier tank's maximum level from85% to 90% Conclusion: The originality of our efforts are not only software but hardware performance improvements. Incidentally the side of software's are change of therapy procedures and protocols, the side of hardware's are replacement of water saving style toilet stool and change of each water-purifier tank's maximum level. Thus even if a long lapse of time, problem such as return to the former conditions may not happen. Besides, We expect that our trials become a new reasonable model in similar situation.

일본향 소형정수기 디자인 개발

정도성 ( Do-sung Jung ) 한국산업디자이너협회 2008 산업디자인학연구 Vol.2 No.1

If we look into the water purifier market environment of Japan for the last several years, it is described as follows. The damage of water contamination due to wariness on contaminated water pipe incident and carcinogens is rising as a great problem in the society. The water supply policy of the government has also determined that spending a vast amount of budget for all daily water supplies (drinking water 1%, cooking related 23%, for bathroom (shower) 27%, laundry 25% and miscellaneous 24%) is meaningless and changed the objective from supplying delicious water to supplying safe water. So the consumer awareness on water quality is increasing each day and the sale of water purifier is showing an increasing trend of about two times every year. But in Japan, more than 100 water purifier related makers are competing while the reality is that small and medium brands without any distinctive features are having a hard time.

정수기내 활성탄에서의 세균생장

이동근 한국환경보건학회 2003 한국환경보건학회지 Vol.29 No.5

Comparison of water qualities, including bacterial distributions and activities, in influent and effluent of a water purifier for drinking water was done to clarify the possibility of bacterial growth on granular activated carbon (GAC) in a water purifier. GAC of two filters, before and after reverse osmosis (RO) filter as pre-GAC and post-GAC filters, were also studied. HPC (heterotrophic plate count) of effluent (7.0×101~6.3공103 CFU/ml) were higher than influent (3.5 공101~1.9°ø103 CFU/ml) in the water purifier until 50 days (summer) and after 50 days, vise versa. HPC was 10 fold higher in pre-GAC than post-GAC filter. It may represent that RO filter can't eliminate all bacteria. Bacterial activities on GAC were 12.13~17.94 mg INT-formazan/g-GAC/h in pre-GAC and 10.68~18.42 mg INT-formazan/g-GAC/h in post-GAC. No pathogen was detected and Acinetobacter sp. were dominant bacteria on GAC. Moraxella, Clavibacter, Pseudomonas, and Corynebacterium sp. were also detected on GAC.

직수정수기의 순간온수 온도제어에 관한 연구

조형석(Hyeong-Seok Jo),이우철(Woo-Cheol Lee) 한국조명·전기설비학회 2021 조명·전기설비학회논문지 Vol.35 No.11

The instant hot water function of the tankless water purifier requires stable temperature control technique because water is passed the hot water module to which power is applied, and the water is instantaneously heated and supplied directly to the user. In this paper, we propose a method to optimize the preheating time by inserting a temperature sensor inside the hot water module to accurately check the current heating state of the hot water module and calculate the amount of heat required for heating to the target temperature. In addition, we propose a duty pattern of the triac on-off control method that makes it easy to calculate the amount of heat even when the control environment changes. The proposed technique is verified stable temperature heating effect through reducing the supplied time to user and deviation of hot water temperature of experiments for outlet temperature measurement using a tankless water purifier.