Journal of Korean Society of Environmental Engineers
/
v.30
no.5
/
pp.491-499
/
2008
It is really urgent to develop wastewater treatment system which is economically efficient, occupies small area for buildup, can be easily operated, discharges small amount of sludge due to the more strict water quality standard, the expensive water and energy cost and so on. This study on treatment of wastewater including nonbiodegadable materials using white-rot fungus biofilm were designed to investigate the submerged type of biofilm, hydraulic retention times, recycle rates, and module turning times. Removal efficiencies of fully exposed biofilm type in atmosphere are similar to submerged biofilm of aeration type. The optimum conditions of white-rot fungus biofilm of fully exposed type in atmosphere are HRT 3$\sim$4 hr, recycle rate 6$\sim$10 Q, module turning times 0.5$\sim$2 times/min. At this time, removal efficiencies of organics were COD$_{Cr}$ 65.0$\sim$69.9%, NBDCOD 70.4$\sim$72.7%, BOD$_5$ 88.8$\sim$90.1%, SS 84.2$\sim$90.4%. Moreover average effluent concentration of BOD$_5$(8.9 mg/L) satisfied water quality standard of heavy water(BOD$_5$ less than 10 mg/L) but concentration of NBDCOD(29.6 mg/L) was higher than water quality standard of heavy water(NBDCOD less than 20 mg/L).
Journal of the Korean Society for Marine Environment & Energy
/
v.7
no.3
/
pp.116-121
/
2004
Treatability tests were conducted to study the feasibility of EMMC process as a recycling-water treatment system in high density seawater aquaculture farm. To study the effect of organic and ammonia nitrogen loading rate on system performance, hydraulic retention time was reduced gradually from 12hr to 10min. The conclusions are can be summarized as follows. When the system HRT was reduced from 12hr to 2hr gradually, there was little noticeable change(reduction) in ammonia nitrogen removal efficiencies. However, removal efficiencies were decreased dramatically when the system was operated under the HRT of less than 2hr. In case of organics(COD), there was no dramatic change in removal efficiencies depending on HRT reduction. COD removal efficiencies were maintained successfully higher than 9% when the system was operated at tile HRT of 10 min. System performances depending on media packing ratio in the reactors were also evaluated. There were little differences in each reactor performances depending on media packing ratio in reactor when the reactors were operated under the HRT of longer than 1hr. However, differences in reactor performances were considerably evident when the reactors were operated under the HRT of shorter than 1hr. When comparing reactor performance among 25%, 50%,7 5% packed reactor, it can be judged that media packing ratio more than 50% plays no significant role in increasing reactor performance. For this reason, packing the media less than 50% is more reasonable way in view of economic. Such a tendency shown in COD removal efficiencies well agreed with the variation of ammonia-nitrogen removal efficiencies according to the media packing ratio in reactors at each HRT. Difference in effluent ammonia-nitrogen concentration between 50% media packing reactor and 75% media packing reactor was negligible. When comparing with the results of 25% packing reactor, difference was not so great.
Journal of Korean Society of Environmental Engineers
/
v.31
no.4
/
pp.256-262
/
2009
The use of hydrodynamic separator is becoming increasingly popular for suspended solids reduction in urban storm runoff. This study is a laboratory investigation of the use of Vortex Screen to reduce the solids concentration of synthesized storm runoff. The synthesized storm runoff was made with water and addition of particles; manhole sediment, road sediment, fly ash, and ployvinyl chloride powder. Vortex Screen was made of acryl resin with 250 mm of diameter and height of 700 mm. To determine the removal efficiency for various influent concentrations of suspended solids (SS) and chemical oxygen demand (COD), tests were performed with different operational conditions. The samples were taken simultaneously at the influent storage tank and effluent tank, and measured SS and COD concentrations. The ranges of surface loading rate were 110 to 1,550 $m^3/m^2$/day, and influent SS concentrations were varied from 141 to 1,986 mg/L. This paper was intended to evaluate the effect of inlet baffle and the ratio of underflow to overflow ($Q_U/Q_O$) on particle separation efficiency for various particle size using Vortex Screen. It was found that when increase of $Q_U/Q_O$ from 10% to 20%, SS removal efficiency was increased about 6%. The range of SS and COD removal efficiencies of road sediment particle size 125<$d_p$<300 ${\mu}m$ were 68.0~81.0%, 53.1~71.9%, respectively. Results showed that SS removal efficiency with inlet baffle improved by about 10~20% compared without inlet baffle.
Park, Jong-Sung;Lee, Ha-Yun;Han, Jong-Hun;Her, Nam-Guk
Journal of Korean Society of Environmental Engineers
/
v.33
no.4
/
pp.281-288
/
2011
Recently, researches that a variety of contaminants in water are removed by sonolysis technology with oxidation and pyrolysis process from cavitation were conducted. However, there are few studies for sonochemical treatment by a pilot-scale ultrasound system. This research focused on developing pilot-scale ultrasound systems, which could be an continuously effective treatment for a large volumes of contaminants, and demonstrating the feasibility of utilizing these systems to remove naphthalene from groundwater. V-120 type reactor was found to be 1.4~2.2 times higher effective than the normal type. A total of three different pilot scale's systems consisted of installing effluent and irrigation water in order to be a continuos system, including supplemental additives, and applying a V-120 type reactor and a external cooling cycle system. Naphthalene levels treated by three systems were lower than a recommended guideline of naphthalene for drinking water in EPA. Especially, the naphthalene removal efficiencies of PS1 and PS2 systems were over 97%. The pilot-scale continuous ultrasound clean-up system delivered over 84~95% naphthalene removal efficiency for treatment of 10~20 liter of groundwater. In addition, the ultrasound system could be successfully applied to the conditions of artificial and genuine groundwater contaminated with naphthalene.
Journal of Korean Society of Environmental Engineers
/
v.30
no.7
/
pp.743-750
/
2008
In water treatment plant the Dissolved Ozone Flotation(DOF) System may be employed because this system has various abilities, such that it can remove SS using microbubbles, and it can exert strong oxidation power in removing taste and odor, color, and microbial agents. In order to investigate effectiveness of the DOF system in water treatment, removal characteristics of various water quality parameters were observed depending on the different levels of ozone concentrations. Removal efficiencies of water quality parameters in DOF system were compared with those in DAF(Dissolved Air Flotation) system and in CGS(Conventional Gravity Settling) system. Optimum ozone dose obtained in the pilot experiments was 2.7 mg/L. With increasing ozone dose higher than 2.7 mg/L, removal rates of turbidity, KMnO$_4$ consumption, UV$_{254}$ absorbance, and TOC were reversely lowered. High concentration of ozone dissociate organic matter in water, so that increasing dissolved organic level in effluent. Removal rates of water quality parameters at optimum ozone dose were obtained, such that removal rates of turbidity, KMnO$_4$ consumption, TOC, and UV$_{254}$ asorbance were 88.9%, 62.9%, 47%, and 77.3% respectively. Removal rate of THMFP was 51.6%. For all the parameters listed above, the DOF system was more effective than the DAF system or the CGS system. It is found that the DOF system may be used in advanced water treatment not only because the DOF system is more efficient in removing water quality parameters than the existing systems, but because the DOF system is also required smaller area than the CGS system for the treatment plant.
A set of lab-scale polymer synthetic fiber packed column wetlands composing three columns (CW1, CW2 and CW3) with different hydraulic regimes, recirculation frequencies and pollutant loading rates, were operated in 2012. Synthetic fiber tested as an alternative wetland medium for soil mixture or gravel which has been widely used, has very high pore size and volume, so that clogging opportunity can be greatly avoided. The inflow to the wetland was artificial stormwater. All the wetlands achieved effective removal of TSS (94%~96%), TCOD (68%~73%), TN (35%~58%), TKN (62%~73%) and NH4-N (85%~ 99%). Particularly, it was observed that COD was released from the fiber during one distinct period in all wetlands. This was probably due to the degradation of polymer fiber, and the released organic matters were found to serve as carbon source for denitrification. In addition, with longer retention time and frequent recirculation, lower effluent concentration was observed. With higher pollutant loading rate, higher nitrification and denitrification rates were achieved. However, although organic matters were released from the fiber, the lack of carbon source was still the limiting factor for the system since the release persisted only for 40 days.
The reuse of wastewater is being diffused to manage and develop the water resources. Generally, the treated wastewater is discharged to the river after being treated to meet the effluent quality standard or reused for diverse uses through the reprocessing. And recently, as the reuse of the treated wastewater is activated, the technologies to utilize for the high quality water resources such as industrial water by reusing the wastewater with Membrane Distillation (MD) are under development. In this study, the direct contact membrane distillation (DCMD) process has been applied to treat sewage discharge water for water reuse. The laboratory scale experiment was performed by using a hydrophobic PVDF membrane with the pore size of $0.22{\mu}m$. The influence of operating parameters, such as feed temperature, feed flow rate, feed concentration, on the permeate flux and rejection has been investigated. All filtration tests were conducted till the feed volume reached a concentration factor of 3.0. Thus, the operating period ranged between 19 hr and 49 hr depending on filtration performance. The results showed that above 92% of TN, TP, COD and TOC in the feed could be rejected regardless of an operating condition. The water flux was ranged from 13.8 to 20.3 LMH. The lowest flux was obtained at the operating condition with the feed temperature of $50^{\circ}C$ and feed flow velocity of 500 mL/min while the highest one was measured with $60^{\circ}C$ and 900 mL/min. When the concentration factor reached 3.0, water flux declined by approximately ranged from 14.5% to 33.3%. But the fouling in MD is almost fully reversible, with more than 90% recovery of permeate water flux following a DI water rinse without the addition of chemical cleaning reagents.
This study was carried to investigate the biodegradability of phenol in the wastewater with the two sludge blanket-packed bed reactor in series. Each reactor had a dimension of 0.09 m i.d. and 1.5 m height and consisted of two regions. The lower region was a sludge blanket of 0.5 m height and the upper region was a packed-bed of 1 m height. The packed bed region was charged with ceramic raschig rings of 10 mm i.d., 15 mm o.d. and 20 mm length. The reactors were operated at 35$\circ$C and the hydraulic retention time(HRT) was maintained 24 hours. The synthetic wastewater composed of glucose and phenol as major components was fed into the reactor in a continuous mode with incereasing phenol concentration. In addition, the nutrient trace metals($Na^+, Mg^{2+}, Ca^{2+}, PO_4^{3-}, NH_4^+, Co^{2+}, Fe^{2+}$ etc.) were added for growing anaerobes. The phenol concentration of the effluent, the overall gas production, the composition of product gas, the efficiency of COD reduction and the duration of acclimation period were measured to determine the performance of the anaerobic wastewater treatment system as the phenol concentration of the influent was increased from 600 to 2400 mg//l. Successfully stable biodegradation of phenol could be achieved with the anaerobic treatment system from 600 to 1, 800 mg/l of the influent phenol concentration. The upper level of influent phenol loading was high enough to meet most of the practical requirement. The duration of acclimation increased with the phenol loading. At steady state of the influent phenol concentration of 1800 mg/l, the treatment performance indicated the phenol reduction efficiency of 99%, the COD reduction efficiency of 99% and the gas production rate of 37 l/day. At the influent phenol concentration of 2400 mg/l, however, the operation of the treatment system was noted unstable. While the concentration of methane in biogas decreased with increasing the influent phenol loading, the carbon dioxide was increased. However, the concentration of hydrogen was varied negligibly. The concentration of methane was high enough to be used as a fuel. As a result, it is suggested that anaerobic phenol wastewater treament was economical in the sense of energy recovery and wastewater treatment.
The various environmental problems that we face on today are basically about environmental quality. Since early 1960s affluent material was produced because of remarkable economic growth by many cooperations. However, for the lack of environmental policy, environmental pollutions has been serious. The central government should transfer the producing and consuming structure to environmental affinity through the regulations for developing Korea as a model of environmental nation which takes an active part in global environmental programme and in which the environment and economy are well harmonized. Moreover, the central government should take the lead in prevention of environmental pollution through the direct policies such as strengthening the discharge limit or setting up environmental basic institutions by securing budget for conserving environment. This thesis emphasize on the public institution among many environmental basic institutions for environmental anti-pollution project. It will find the problems with running those institutions, and will suggest the preview of improvement. Also, it is necessary to investigate of variation trend for inflow and pollutant loading to environmental infrastructure as increased of the diffusion rate as established and maintenance of sewer system. The purpose of this study is to investigate for inflow and pollutant loading to environmental infrastructure, and also to provide the method of efficiently maintenance and management. The results obtained were summarized as follows; 1. Survey of actual condition on operation and management of environmental infrastructure was evaluated the propriety of treatment process and problem of plant management. 2. Analysis of pollutant loading contribution for river system of environmental infrastructure with data analysis of water quality measuring network. 3. To investigate on case study for efficiently maintenance and management of environmental infrastructure. The result on this study was provide the method of efficiently maintenance and management with survey for establish and repair of sewer system and survey of actual condition on operation and management of environmental infrastructure in the water area of discharge to Geum River System. Application as guideline for establish and management of environmental infrastructure, and management of Geum River System. Also, application for preliminary data for fulfill-assess of total effluent regulation of water pollution.
Kwon, Se Young;Kang, Min Sun;Kim, Se Woon;Shin, Jung-Hun;Choi, Han-Na;Jang, Hoon;Cho, Jin Woo
Journal of Korean Society of Water and Wastewater
/
v.28
no.1
/
pp.13-23
/
2014
A lab-scale Anaerobic Baffled Reactor (ABR) was applied to treat a primary sludge taken from a municipal wastewater treatment plant. In this experiment, acidogenic reaction was promoted by operating the ABR with short hydraulic retention time (HRT) to produce sufficient volatile fatty acids (VFA) instead of production of methane. The performance of ABR on the VFA production and total solids reduction was observed with different operating conditions with 2, 4, 6, and 8 days of HRT. Corresponding organic loading rates were 6.7, 3.4, 2.2, and $1.6kgCOD_{cr}/m^3{\cdot}day$. As HRT increased the removal rate of TCOD was also increased (82.5, 84.2, 96.9, and 95.9 % in average for HRT of 2, 4, 6, and 8 days, respectively) because the settlement of solids was enhanced in the baffle by the decrease of upflow velocity. At HRT of 2 days the average concentration of VFA in the effluent was measured at $1,306{\pm}552$ mgCOD/L corresponding to 107 % increment as compared to the VFA concentration in the influent. However, as HRT increased VFA concentraiotn was decreased to $143{\pm}552$ mgCOD/L at HRT of 8 days. The reduction rates of total solids were 12.2, 26.5, 24.8, and 43.0 % for HRT of 2, 4, 6, and 8 days. As HRT increased the hydrolysis of organic particulate matters in the reactor was enhanced due to the increasing of solids retention time in the baffle zone with low upflow velocity in long HRT condition. Consequently, we found that a primary sludge became a good source of VFA production by the application of ABR process with HRT less than 4 days and the 12-26 % of total solids reduction was expected at these conditions.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.