• Environmental Engineering Research
• /
• 제19권4호
• /
• pp.309-316
• /
• 2014

The water quality improvement of golf course ponds, as representative stagnant stream channels, was evaluated by applying a biological activated carbon (BAC) process composed of four consecutive activated carbon reactors. The study was performed from autumn to winter in order to evaluate the feasibility of the BAC process under low temperature conditions. In the study, water quality of pond A (target pond) and pond B (reference pond) were monitored. Pond water was pumped into the BAC process, and was then returned to the pond after treatment. The optimal conditions were determined to be 2 hr of empty bed contact time (EBCT) at a temperature above $4^{\circ}C$, in which improvements of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) of pond A compared to pond B were 3.62%, 3.48% and 1.81%, respectively. On the other hand, as the temperature was below $4^{\circ}C$, some degree of water quality improvement was achieved even when EBCT were 1 or 0.5 hr, suggesting that the BAC process can be successfully applied for the improvement of pond water quality in winter months. The values of biomass concentration and microorganism activity in each condition were highest where 2 hr of EBCT was applied at a temperature above $4^{\circ}C$, but values were similar throughout all treatment conditions, and thus, adsorption is considered to be the dominant factor affecting process efficiency. From the denaturing gel gradient electrophoresis (DGGE) results, no significant differences were observed among the activated carbon reactors, suggesting that the number of reactors in the system could be decreased for a more compact application of the system.

• 한국물환경학회지
• /
• 제22권6호
• /
• pp.996-1003
• /
• 2006

The absorption characteristics of powdered activated carbon doped by transition-metal nanoparticles were investigated to enhance the remove efficiencies of $TCOD_{Mn}$ and Color from the flexo-inks wastewater. According to the adsorption dynamics of PAC and MPAC, the optimal dosage of activated-carbon adsorbents was 3 g/L under the reaction conditions of pH6.0, 30 mill of reaction time, 240 rpm of mixing intensity. The removal efficiencies by the optimal dosages were maximized as 19% $TCOD_{Mn}$, 57% Color for PAC and 88% $TCOD_{Mn}$, 95% Color for MPAC. Freundlich indexes of isotherm absorption were estimated as follows: i) For PAC, k=-8.11, 1/n=2.98, r=0.91 in the raw water, and k=0.14, b/n=0.75, r=0.96 in the biological treatment water, ii) For MPAC, k=2.69, 1/n=0.21, r=0.80 in the raw water, and k=0.74, 1/n=1.17, r=0.95 in the biological treatment water. MPAC (Powdered activated carbon doped by transition-metal nanoaprticles) was very effective in the removal of organics from the raw water and biological treatment water, as Freundlich indexes of 1/n for both types of water were estimated less than 2.0.

• 대한환경공학회지
• /
• 제22권6호
• /
• pp.1037-1044
• /
• 2000

본 연구에서는 국내에서 쉽게 구할 수 있으며 탄화시 높은 강도를 가질 수 있는 참나무를 이용하여 생물 활성탄 공정(BAC)에 적합한 활성탄, 즉 흡착뿐만 아니라 미생물의 안식처로서의 역할을 할 수 있는 거대 세공이 많이 발달된 활성탄을 제조하는데 그 주안점을 두었다. 활성탄의 제조는 인산 침적에 의한 화학적 활성화법을 이용하여 제조하였고 제조된 활성탄의 요오드 흡착력(mg/g), 메틸렌 블루 탈색력(mg/g), B.E.T Method에 의한 비표면적($m^2/g$), 세공 크기 분포(Pore size distribution)를 분석하여 현재 생물 활성탄 공정에 많이 사용되고 있는 P사의 'picabiol' 활성탄과 비교하였다. 본 연구에서 사용된 화학적 활성화법의 주인자는 인산의 침적농도, 활성화 용도, 그리고 활성화 시간이다. 이중 활성화 시간은 예비 실험으로 3시간으로 고정시켰다. 최적 활성화 온도와 인산 첨적 농도를 찾기 위하여 활성화 온도는 $600^{\circ}C$에서 $800^{\circ}C$ 로 변화시켰으며 인산 침적 농도는 35wt%에서 50wt%로 변화시켰다. 이렇게 제조된 활성탄 중 $800^{\circ}C$에서 활성화시켰을 때 모든 인산 침적 농도에서 요오드 흡착력(1000~1100 mg/g)과 메틸렌 블루 탈색력(200~400 mg/g)으로서 가장 높은 효율의 활성탄을 얻을 수 있었으며 picabiol과 비교하여 보았을 때 비슷하거나 더 높은 효율의 활성탄을 제조할 수 있었다.

• 공업화학
• /
• 제32권1호
• /
• pp.97-101
• /
• 2021

스코리아와 활성탄의 혼합 충전탑에서 중금속과 유기물의 흡착 특성, 스코리아의 물리화학적 특성과 관능기를 조사하였다. 스코리아의 혼합비율이 증가할수록 카드뮴, 니켈, 크롬, 납 이온의 평균제거율은 증가하였으나, 벤젠과 톨루엔의 평균 제거율은 감소하였다. 스코리아와 활성탄의 혼합 충전탑은 중금속과 유기물의 동시 제거에 효과적으로 사용될 수 있었다. 스코리아는 Si-H와 Si-O 작용기를 갖고 있으며, 이중 Si-O 관능기가 중금속의 흡착에 크게 기여함을 확인할 수 있었다.

• 상하수도학회지
• /
• 제29권1호
• /
• pp.47-55
• /
• 2015

Recently, the production of taste and odor (T&O) compounds is a common problem in water industry. Geosmin is one of the T&O components in drinking water. However, geosmin is hardly eliminated through the conventional water treatment systems. Among various advanced processes capable of removing geosmin, adsorption process using granular activated carbon (GAC) is the most commonly used process. As time passes, however GAC process changes into biological activated carbon (BAC) process. There is little information on the BAC process in the literature. In this study, we isolated and identified microorganisms existing within various BAC processes. The microbial concentrations of BAC processes examined were $3.5{\times}10^5$ colony forming units (CFU/g), $2.2{\times}10^6CFU/g$ and $7.0{\times}10^5CFU/g$ in the Seongnam plant, Goyang plant and Goryeong pilot plant, respectively. The dominant bacterial species were found to be Bradyrhizobium japonicum, Novosphingobium rosa and Afipia broomeae in each plants. Removal efficiencies of $3{\mu}g/L$ geosmin by the dominant species were 36.1%, 36.5% and 34.3% in mineral salts medium(MSM) where geosmin was a sole carbon source.

• 한국환경과학회지
• /
• 제16권6호
• /
• pp.671-675
• /
• 2007

The objective of this study was to clarify the characteristics of the removed micropollutant since the breakthrough of adsorption ability was occurred in biological activated carbon(BAC) process. The removal efficiency of DOC (Dissolved Organic Carbon) was 36 % in the breakthrough of BAC occurred by NOM (Natural Organic Matter). The most of removal DOC was found out the adsorbable and biodegradable DOC (A&BDOC). But it was not clear to remove by any mechanism because A&BDOC have simultaneously the adsorption of activated carbon and biodegradation by microorganism in BAC. The removal of bromophenol was examined with BAC and rapid sand filter, for investigation of DOC removal mechanism in the breakthrough of BAC. In this experiment, BAC filter has been operated for 20 months for the treatment of reservoir water. The BAC filter was already exhausted by NOM. Bromophenol, adsorbable and refractory matter, was completely removed by BAC filter. Therefore, it might be removed by the adsorption in BAC. Adsorption isotherms of bromophenol were compared to two BACs which was preloaded with 500 daltons and 3,000 daltons of NOM. BAC preloaded with 3,000 daltons of NOM was not decreased to the adsorbability of bromophenol but BAC preloaded with 500 daltons of NOM was greatly decreased to it. These result indicated that NOM of low molecular weight can be removed by adsorption after a long period of operation and the breakthrough by NOM in BAC. Therefore, micropollutants might be removed through adsorption by saturated BAC.

• 생명과학회지
• /
• 제22권9호
• /
• pp.1237-1242
• /
• 2012

정수처리 공정에서 생물활성탄(BAC) 공정은 미생물의 유기물 제거능을 극대화시킨 일종의 생물여과 공정이다. 본 연구는 낙동강 원수를 이용하여 재질이 다른 생물활성탄을 사용하고 있는 정수장을 대상으로 세균 군집을 조사하였다. 실험결과 석탄계 재질의 BAC 부착세균 생체량 및 활성도가 각각 $1.20{\sim}34.0{\times}10^7$ CFU/g, 0.61~1.10 mg-C/$m^3{\cdot}h$의 범위를 보여 세균 생체량과 DOC 제거율은 석탄계 재질이 가장 높은 것으로 나타났다. 부착세균을 동정한 결과 Pseudomonas 속이 우점하였으며, 그 다음으로 Chryseomonas 속, Flavobacterium 속, Alcaligenes 속, Acinetobacter 속, Sphingomonas 속 등의 순으로 동정되었다. 그리고 Pseudomonas cepacia는 석탄계 재질, Chryseomonas luteola는 목탄계 재질의 우점세균으로 조사되었다.

• Environmental Engineering Research
• /
• 제25권4호
• /
• pp.588-596
• /
• 2020

This study was carried out to increase the treatment efficiency through the improvement of the conventional biological process, and to propose the optimal treatment direction. The optimal treatment conditions were derived based on the results of the spike damage tests in each single process. The removal efficiency of micropharmaceuticals was further increased when an ozone treatment process was added to the biological process compared to the single process. The soil and activated carbon adsorption process was introduced in the post-treatment to remove the micropharmaceutical residues, and the removal efficiency of the pharmaceduticals in the final effluent was more than 85% in spike damage experiment. In particular, the continuous process of biological treatment-ozone-adsorption could ensure the stable treatment of micropharmaceuticals, which had not been efficiently removed in the single process, as it showed more than 80% removal efficiency. Therefore, it is expected that the addition of the ozone oxidation and activated carbon adsorption process to the existing sewage treatment facilities can contribute to the efficient removal of micropharmaceuticals.

• 한국물환경학회지
• /
• 제22권1호
• /
• pp.83-90
• /
• 2006

Performance and operation of BAC in ozone-BAC advanced water treatment process were investigated using the pilot scale test plant built in D water purification plant. The performance was evaluated by the removal efficiencies of DOC, BDOC, ammonia nitrogen and THMs. The effect of EBCT on DOC removal was experimented for an effective operating condition, and the amount of attached biofilm was analyzed in various water temperatures and position of BAC. Two removal mechanisms, adsorption and biological decomposition by attached biofilm, were predominant to decrease the concentration of various contaminants. DOC was removed 40%, and the removal rate was decreased in winter time due to the lowered activity of attached biofilm. BDOC was effectively removed. THMs and ammonia nitrogen were mainly removed not in ozonation process but in BAC. Water temperature deeply influenced in removal efficiency of ammonia nitrogen. The amount of attached biofilm depended on water temperature and height of packed activated carbon column. Considering DOC removal efficiency and design EBCT of commercial BAC plant, the proper EBCT was 12.5 minutes.

• Korean Chemical Engineering Research
• /
• 제49권4호
• /
• pp.456-459
• /
• 2011

본 연구는 흡착 능이 서로 다른 두 가지 활성탄을 혼합하여 최적의 흡착 능을 발휘코자 혼합할 때 그들의 최적혼합비를 구하는 방법을 제시하고자 하였다. 활성탄의 세공특성과 흡착 능은 BET-분석에 의해 얻어지는 흡착등온곡선으로 판별하며 이는 역시 흡착필터설계의 기본적 정보를 제공한다. 따라서 고도의 BET-model의 흡착 능을 보이는 석탄 계활성탄과 낮은 Langmuir-model을 보이는 야자각계 활성탄의 혼합하는 extreme case와, 고, 저 비표면적을 가진 두 가지 활성탄을 혼합하는 middle case 및 전, 후 case의 상호 교차 배합하는 cross case 등, 3가지 시험을 수행했으며, 이를 위해 시판 품 외에 국내 한 공인 연구소가 연구용시료로서 제공한 고비표면적의 두 가지 활성탄에도 적용하여 본 방법의 타당성을 확인하였다.