• 한국환경과학회지
• /
• 제23권9호
• /
• pp.1655-1662
• /
• 2014

A comprehensive fractionation technique was applied to a set of water samples obtained along drinking water treatment process with ozonation and biological activated carbon (BAC) process to obtain detailed profiles of dissolved organic matter (DOM) and to evaluate the haloacetic acid (HAA) formation potentials of these DOM fractions. The results indicated that coagulation-sedimentation-sand filtration treatment showed limited ability to remove hydrophilic fraction (28%), while removal of hydrophobic and transphilic fraction were 57% and 40%, respectively. And ozonation and BAC treatment showed limited ability to remove hydrophobic fractions (6%), while removal of hydrophilic and transphilic fractions were 25% and 18%. The haloacetic acid formation potential (HAAFP)/dissolved organic carbon (DOC) of hydrophilic fraction was the highest along the treatment train and HAAFP/DOC of hydrophilic fraction was higher than hydrophobic and transphilic fraction as 23%~30%, because of better removal for hydrophobic fraction both in concentration and reactivity.

• KSBB Journal
• /
• 제16권4호
• /
• pp.332-336
• /
• 2001

본 연구에서는 정수처리 중에서 BAC(Biological activated carbon) 처리의 생물분해능과 같이 NOM의 생분해성 부분을 제거하고자 로프형 미생물 담체를 침전조에 적용하는 공정을 시도하였다. 다양한 운전조건을 적용하여 DOC와 UV$_{254}$ 그리고, 탁도 제거효과를 평가하였는데, 담체 설치는 일반적인 정수처리 공정을 모사한 pilot plant에 첫 번째로 아무 전 처리도 거치지 않은 팔당원수를 바로 지나도록 하였고(Media 1), 두 번째는 팔당원수를 오존으로만 전처리한 후 지나도록 하였으며(Media 2), 세 번째는 전 오존과 응집-침전과정이 끝난 후 지나도록 하였다(Media 3). 원수의 DOC 농도는 1.3~3.4 mg/L이고, UV$_{254}$는 0.027~0.039 ($cm^{-1}$ /)이며, 탁도는 0.3~4.5 NTU 였다. 평균 DOC 농도는 media 1, 2, 3에서 각각 2.2 mg/L, 1.8 mg/L, 1.3 mg/L를 보였다. 반면에 침전조에서는 1.5 mg/L의 농도를 보여 media 3에서 가장 높은 제거량을 나타내었다. 평균 UV$_{254}$ 값은 media 1, 2, 3에서 각각 0.037 ($cm^{-1}$ /), 0.027 ($cm^{-1}$ /), 0.014 ($cm^{-1}$ /)를 나타내었으며, 침전조에서의 UV$_{254}$ 값은 media 3와 비슷한 0.014 ($cm^{-1}$ /)를 보였다. 평균 탁도는 media 1, 2, 3에서 각각 1.1 NTU, 0.9 NTU, 0.5 NTU를 나타내었다. 위의 결과를 보면 로프형 미생물 담체 침전조는 일반적인 침전 공정에 바로 적용할 수 있는 경제적인 장치로 활용 가능할 것이다.

• 한국물환경학회지
• /
• 제26권3호
• /
• pp.446-453
• /
• 2010

This study was investigated nine nitrosamines in small tributary rivers, sewage treatment plants (STPs) and drinking water treatment plants. They are N-nitrosodimethylamine (NDMA), N-nitrosomethylethylamine (NMEA), N-nitrosodiethylamine (NDEA), N-nitrosopyrrolidine (NPYR), N-nitrosodi-n-propylamine (NDPA), N-nitrosomorpholine (NMOR), N-nitrosopiperidine (NPIP), N-nitrosodi-n-butylamine (NDBA) and N-nitrosodiphenylamine (NDPHA). The nine nitrosamines were analyzed by gas chromatography mass spectrometry (GC/MS) using solid phase extraction (SPE) with a coconut charcoal cartridge. Among the nine nitrosamines, NDMA, NMEA, NDEA, NDPA NDBA and NDPHA were detected in small tributary rivers and sewage tretment plants. In small tributary rivers, NDMA, NMEA, NDEA, NDPA, NDBA and NDPHA were obtained as ND~16.4 ng/L, ND~17.7 ng/L, ND~102.4 ng/L, ND~455.4 ng/L, ND~330.1 ng/L and ND~161.0 ng/L, respectively. Also NDMA, NMEA, NDEA, NDPA and NDBA were investigated ND~821.4 ng/L, 22.5~55.4 ng/L, 53.2~588.5 ng/L, ND~56.6 ng/L and ND~527.9 ng/L in STPs, respectively. In drinking water treatment plants, NMEA and NDEA concentration were increased to as high as 38.8 ng/L after ozonation process. However nitrosamines were decreased subsequent biological activated carbon (BAC) treatment process. It was supposed that nitrosamines were formed by $O_3$ oxidation and were removed by biodegradation of BAC.

• 대한환경공학회지
• /
• 제31권2호
• /
• pp.96-101
• /
• 2009

생물활성탄 재질별 sulfonamide계 항생물질 5종의 생분해능을 조사한 결과 유입수의 수온 $25^{\circ}C$에서 EBCT 변화에 따른 생물분해율을 평가한 결과, 석탄계 재질의 생물활성탄은 EBCT 5~20분에서 18~82%, 야자계나 목탄계의 경우는 11~67% 및 4~56%로 나타나 석탄계 재질의 생물활성탄에서 가장 높은 생물분해능을 나타내었다. Sulfonamide계 5종에 대한 물질별 생분해능을 평가한 결과, 석탄계 재질의 생물활성탄에서 5~20분의 EBCT에서 SCP, SMT 및 STZ는 30~80%, SDM과 SMX는 18~70% 정도의 생분해율을 나타내어 SDM과 SMX가 다른 3종 보다는 생물분해능이 낮은 것으로 나타났다. 유입수의 수온 상승에 따라 5~20분의 EBCT에서 생물분해율은 크게 증가하였고, 유입수의 수온이 $5^{\circ}C$일 경우 sulfonamide계 항생물질 5종에 대한 생물분해 속도 상수는 0.0094~0.0118 $min^{-1}$, 반감기는 58.7~73.7분으로 나타났으며, 수온이 $15^{\circ}C$ 및 $25^{\circ}C$일 경우는 생물분해 속도상수가 0.0307~0.0397 $min^{-1}$ 및 0.0468~0.0718 $min^{-1}$로 나타났고, 반감기 17.5~22.6분 및 9.7~14.8분으로 나타났다. 유입수의 수온이 $5^{\circ}C$에서 $15^{\circ}C$로 상승할 경우 sulfonamide계 항생물질 5종에 대한 생물분해 속도상수는 3.2~3.8배 정도 증가하였으며, 수온이 $15^{\circ}C$에서 $25^{\circ}C$로 상승할 경우는 1.5~1.9배 정도 증가하는 것으로 나타났다.

• 대한환경공학회지
• /
• 제31권5호
• /
• pp.378-381
• /
• 2009

본 연구에서는 BAC 공정을 장기간 운전하면서 유입수중의 $Br^-$ 농도변화에 따른 THMFP 제거율을 평가하였다. BAC 공정을 장기간 운전하면서 THMFP 구성종별로 제거능을 살펴본 결과, $CHCl_3$ 생성능의 경우는 계절변화에 따른 유입수중의 $Br^-$ 농도변화에 따라 관계없이 우수한 제거능을 나타내었으나, 브롬계 THM 생성능의 경우는 유입수중의 $Br^-$/DOC 비가 증가할수록 제거율은 저하되었다. 또한, BAC 공정에서의 THMFP 구성종별로 제거특성을 살펴본 결과, 유입수의 $Br^-$/DOC 비가 높은 경우에 EBCT가 증가할수록 $CHCl_3$ FP의 제거율은 증가하였으나 브롬계 THMFP의 경우는 EBCT가 증가할수록 감소하는 경향을 나타내었고, THMFP 구성종의 브롬원자 개수가 많아질수록 제거율은 감소하였다.

• 상하수도학회지
• /
• 제9권2호
• /
• pp.97-107
• /
• 1995

Today a conventional water treatment system has many problems. The ozone/GAC process, sometimes termed Biological Activated Carbon(BAC), appeared to be effective for the removal of soluble organic matters in the drinking water. The water quality of Nak-dong river in Pusan, generally shows BDOC 30-40% and NBDOC 60-70%. The pilot plant installed at the Duk-san water works that was been largest treatability(1,650,000ton/day) in Pusan. A experimental water in the pilot plant made use of the water after sand-filteration. Following results are drawn from this study. Initial adsorption velocity($DOC/DOC_o/T$) in the pure adsorption of GAG had a 0.0225, it's velocity changed to 0.006 after ozone added and the optimum ozone dose ranged of $1.4-2.0mgO_3/L$. A experimental water in the pilot plant composed with humic material(78%). Humic material composed with humic acid(20%) and fulvic acid(56%), and it's rate changed to 18 and 50% respectively after ozone added. DOC constantly decreased in the EBCTs and removal efficieny in the 15min of EBCT was 45-50%. It showed the largest removal rate of BDOC in the EBCT 5 and among the season, characteristics of removal varied. The HPC distributed over $10^6-10^7CFU/cm^3$ in the bed depth and among the season, distribution of HPC were differential.

• 상하수도학회지
• /
• 제28권4호
• /
• pp.367-376
• /
• 2014

This study assessed the removal efficiency of NOM which is known as the precursors of DBPs in advanced water treatment using the ceramic membrane filtration, introduced the first in the nation at the Y water treatment plant (WTP). It is generally well-known that the removal of NOM by MF Membrane is very low in water treatment process. But, the result of investigation on removal efficiency of NOM in advanced water treatment using the ceramic membrane was different as follows. The removal rate of organic contaminant by the ceramic membrane advanced water treatment was determined to be 65.5% for the DOC, 85.8% for UV254, and 77 to 86% for DBPFP. The removal rate of pre-ozonation was found to be 6 to 15% more effective compared with the pre-chlorination. The removal rate of DOC and $UV_{254}$ in biological activated carbon(BAC) process was over 50% and 75%, respectively although the rate was decreased 10 ~ 20% according to analysis items in converting from GAC to BAC.

• 한국환경과학회지
• /
• 제13권1호
• /
• pp.55-59
• /
• 2004

The effect of ozone on the formation and the removal of disinfection byproducts(DBPs) of chlorination process was studied to elucidate the performance of water treatment process. The samples of raw water, prechlorination process, and preozonation process were analyzed quantitatively according to the Standard Methods for the Examination of drinking water. As a result, most of total trihalomethanes(THMs) which were formed in prechlorine treatment process was not removed in the preozonation process. Most of haloacetic acids(HAAs), haloacetonitriles(HANs), and chloral hydrate(CH) was removed in sedimentation and biological activated carbon(BAC) filtration processes. However, DBPs were increased more or less by postchlorine step. In particular, the formation of THMs and HAAs depends on ozone more than chlorine, but, the formation of HANs and CH depends on chlorine more than ozone. The seasonal variation of DBPs concentration for the year needs to be investigated to study the temperature effect because DBPs strongly depend on temperature among various efficient factors.

• 유기물자원화
• /
• 제13권4호
• /
• pp.136-147
• /
• 2005

난분해성 유기물과 암모니아성 질소의 동시제거를 위해 간헐폭기 생물활성탄 유동상법을 이용하여 고농도 유기물함유 침출수에 대하여 실험을 수행하였다. 간헐폭기시 고려되어야 하는 폭기 시간과 비폭기 시간에 대하여 실험적 검토를 수행하였고 자동컴퓨터제어 가능성에 대하여 고찰하여 보았다. 그 결과 생물활성탄 유동상 반응조에 충전한 활성탄의 물리적 흡착능은 초기의 처리효율에 크게 기여하였으며 간헐폭기 생물활성탄 유동상에 의한 침출수 처리시 정상상태에 도달하는 시간은 40일 정도이었고 TOC와 암모니아성 질소 처리시 양호한 프로세스임을 알 수 있었다. 폭기 및 비폭기시간은 60분 폭기/60분 비폭기의 조건이 30분 폭기/90분 비폭기에 비해 처리효율이 양호하게 나타났고 고농도 유기물함유 침출수 처리실험에서 간헐폭기 생물활성탄 유동상에 의한 처리방법은 높은 TOC제거율, 질산화율 및 탈질율, 난분해성 유기탄소 제거율을 확인할 수 있었다. 또한 간헐폭기시 ORP 곡선의 변화에서 나타나는 굴곡점은 무산소상태의 종결점을 나타내는 파라메터로 이용가능하며 이를 간헐폭기 반응조의 최적 운전모드를 설정하는데 응용할 경우 소규모 자동화가 가능할 것으로 판단되었다.

• 한국환경과학회지
• /
• 제21권7호
• /
• pp.837-843
• /
• 2012

The aims of this study were to investigated the occurrence of caffeine and carbamazepine in Nakdong river basin (8 mainstreams and 2 tributaries) and the behavior of caffeine and carbamazepine under drinking water treatment processes (conventional and advanced processes). The examination results showed that caffeine was detected at all sampling sites (5.4~558.5 ng/L), but carbamazepine was detected at five sampling sites (5.1~79.4 ng/L). The highest concentration level of caffeine and carbamazepine in the mainstream and tributaries in Nakdong river were Goryeong and Jinchun-cheon, respectively. These pharmaceutical products were completely removed when they were subject to conventional plus advanced processes of drinking water treatment processes. Conventional processes of coagulation, sedimentation and sand-filtration were not effective for their removal, while advanced processes of ozonation and biological activated carbon (BAC) filtration were effective. Among these pharmaceuticals, carbamazeoine was more subject to ozonation than caffeine.