광산폐수의 중금속 제거에 대한 온도의 영향

백병천,김광복 國立 麗水大學校 環境問題硏究所 1999 環境硏究論文集 Vol.2 No.-

SRB(Sulfate Reducing Bacteria) converts into sulfide using an organic carbon source as the electron donor. The sulfide formed precipitates the various matals present in AMD(Acid Mine Drainage). In this study, the effects of temperature on sulfate reduction and heavy metals removal from AMD were investigated in batch and continuous flow reactors operating at the range from 15˚C to 40˚C. Reduced sulfate/removed COD(mg/mg) ratio maximized at temperature of 30˚C in the batch reactor operating at COD(glucose)/sulfate ratio of 0.5 and then removal efficiencies of heavy metals were 97.5% of Cu, 99.99% of Pb, 99.99% of Cr, 49% of Mn, 98% of Zn, 99.99% Cd and 92.4% of Fe. Two anaerobic floating media reactors were continuously operated at hydraulic retention time of 3days, COD/sulfate ratio from 0.3 to 0.8, temperature from 30˚C to 35˚C, and alkalinity of 1000mg/ℓ (as CaCO_(3)). At CCD/sulfate(SO_(4)^(2-)) ratio of 0.5 and temperature of 35˚C, the ratio of reduced sulfate(SO_(4)^(2-))/removed COD(mg/mg) kept about 1 and the reactor achieved 99.99% of Cr, Pb and Fe, 98% of Cd, and 90% of Mn removal efficiencies, respectively. Decreasing temperature to 30˚C increased the ratio of reduced sulfate(SO_(4)^(2-))/removed COD(mg/mg) to 1.31. Amount of sulfate reduction maximized at the temperature of 30˚C and the COD/sulfate ratio of 0.4 in the influent and then removal effciencies of heavy metals were 100% of Fe, 100% of Pb, 99.99% of Cr. 97.3% of Mn, 99.9% of Zn,99.9% of Cd and 99.9% Cu.

UASB 반응조내 생물학적 거동분석을 위한 모델링

백병천,전관수 麗水水産大學校産業技術硏究所 1992 産業基術硏究所 論文集 Vol.1 No.-

Modeling made it possible to predict the behavior of constituents and microorganisms, and microorganisms, and the changes of process variables with respect to the bed height by assuming the sludge bed zone in UASB(upflow anaerobic sludge blanket) reactor to be a series of CFSTRs(continuous flow stirred tank reactors) of which the volume is proportioned to the gas quantity passing the segmented zone. Mathematical simulations were attemped to identify the balance and distribution of the two microbial populations, which were divided into two groups of acidogenic and methanogenic bacteria, as well as the responces of reactor to the operational conditions in terms of the bed height. Considering the constituents as complex substrates composed of hydrolyzed and nonhydrolyzed materials and VFAs(volatile fatty acids), prediction of the concentration of each constituent was allowed. This reserch indicated that the UASB reactor was relatively stable to shock loading and that the lower part placed below the height of 20%-30% of the sludge bed probably served as a shock absorbing zone. About 70% of organic COD was removed in the lower 55% portion of the sludge bed height.

실폐광폐수의 중금속 제거를 위한 AFMR 공정 운전 연구

백병천,김광복 國立 麗水大學校 環境問題硏究所 2000 環境硏究論文集 Vol.3 No.-

This research is to establish operation technology of AFMR(Anaerobic Floating Media Reactor) Process for heavy metals removal from raw acid mine drainage. Two AFMR were operated at hydraulic retention time(HRT) of 3days, COD/sulfate ratio of 0.5, temperature of 30℃, and alkalinity from 600㎎/ℓ to 1,000㎎/ℓ (as CaCO_(3)). AT COD/sulfate(SO_(4)^(2-)) ratio of 0.5 and temperature of 30℃, the maximum ratio of reduced sulfate(SO_(4)^(2-))/removed COD(㎎/㎎) kept about 1.34 and the reactor achieved 99.9% of Cr, Cu and Fe, 99.4% of Pb, 99% of Zn, 98% of Cd, and 92.5% of Mn removal efficiencies, respectively. Increment of alkalinity in influent can lead to reduce level of heavy metals in effluent . In order to achieve the efficient removal of heavy metal from raw acid mine drainage, alkalinity of range from 800㎎/ℓ to 1,000㎎/ℓ (as CaCO_(3)) has to be supplied to the influent feed, Sulfate reducing bacteria(SRB) of rods and bacillus types were also observed on surface floating media used in this study.

생물여과반응기에서 폐가스의 VOC 제거에 대한 전자수용체의 영향

백병천,Xueqing Zhu 國立 麗水大學校 環境問題硏究所 1998 環境硏究論文集 Vol.1 No.-

Biofiltration is fast becoming the technology of choice for the control of the volatile organic compounds (VOCs) present in air streams due to its cost-effectiveness. This study was carried out to investigate the effect of electron acceptors on the performance of biofiltration process treating diethyl ether as a VOC substrate in waste gases. Two trickle bed biofilters with pelletized synthetic media were operated co-currently at a empty bed hydraulic retention time of 25 seconds, inlet gas flow rate of 8.64㎥/day, Nutrient liquid flowrate of 1L/day, and COD loading rate from 1.8 to 7.1㎏ COD/㎥.day. Nitrate and oxygen were used as the electron acceptor for the VOC (ether) biodegradation. By increasing the concentration of oxygen in the feed to this biofilter from 21% (ambient air) to 50% and 100% while maintaining an influent VOC (ether) concentration of 133 ppm_(v) and a feed nitrate concentration of 67㎎/ℓ, the performance of the biofilter was not significantly affected. However, the VOC (ether) removal efficiencies improved with increasing influent nitrate concentration. which suggest that nitrate is a good electron acceptor more than oxygen. It was also found that nitrate was rate limiting as a growth nutrient rather than as an electron acceptor, and that resistance to the transport of nitrate into the biofilm led to nutrient limitations in the deeper layers of the biofilm.

Purge & Trap, GC/MSD를 이용한 해수 중 휘발성유기화학물질 분석

김유곤,백병천,이원준 國立 麗水大學校 環境問題硏究所 2002 環境硏究論文集 Vol.5 No.-

Analysis items of this study were 1,1-dichloroethene, dichloromethane, chloroform, 1,2-dichloroethane, 1,1,1-trichloroethane, benzene, carbontertrachloride, toluene, ethylbenz ene, m,p-xylene, styrene, o-xylene. Equipment of analysis was purge & Trap/HP-6890GC/5973MSD, GC operating condition was carrier gas 99.999% Helium-0.7㎖/min, Trap meterial Tenax/SG?Charcoal, Column HP-PONA(Crosslinked Methyl Siloxane, 50m×0.2mm×0.5㎛), Oven program 35℃(10min)-4℃/min 150℃-1 5℃/min 200℃(5min), Aux 280℃, MS Source 230℃, MS Quad 150℃ Result of RSD% measurement was chloroform 9.37%, 1,2-dichloroethane 5.79%, 1,1,1-trich loroethane 12.56%, benzene 4.31%, carbon tetrachloride 15.35%, toluene 3.89%, ethylben zene 5.69%, m,p-xylene 5.65, styrene 4.02%, o-xylene 2.94%. Result of analysis showed that 1,1,1-trichloroethane, carbontetrachloride, dichloromethane were not detected, 1,1-dichloethane was detected level of 0.19ppb, 0.26ppb in 1st sampling point 6, 7, 1,2-dichloromethane 0~7.25ppb, benzene 0~0.9ppb, toluene 0/11~1/79ppb, ethyelbenzne 0~2.15ppb, m,p-xylene 0~2.32ppb, styrene 0~0.8ppb, o-xylene 0~0.68ppb.

ID-GC/MS에 의한 쌀 중의 잔류농약 인증표준물질

김유곤,김달호,백병천,이우범 國立 麗水大學校 환경문제硏究所 2001 環境硏究論文集 Vol.4 No.-

The CRM used in evaluation of effectiveness, calibration or analysis equipment when you analyse in material of rice powder or similar matrix. Analytical items were γ-HCH, p,p'-DDE, endosulfan-2, samples of achieved pertreatment analized each component indivisually. Control mode of MS used selected ion monitering(SIM). GC is 6890GC of Agilent Technology company and MS is JMS 700 of Jeol company. MS operating condition was Electron impact ionization with 70eV. 300A, GC operating condition was Column : Rtx-5MS 30m*0.25m ID*0.25um, Oven Temp 90℃(3min)-20℃/min-280℃(2min), Injection port 250℃, splitless, Carrier Gas He with 1mL/min. Water contents was 12.534% and dry mass correction factor 1.143. CRM certified values of the experiment result were p,p'-DDE 0.165±0.011,mg/kg, γ-HCH 0.0129±0.0011mg/kg, endosulfan-2 0.0216±0.0027mg/kg. The numbers following the symbol ± are the numerical values of expanded uncertainties, U=ku_(c) of measurement values preceding the symbol. The level of confidence for the expanded uncertainties are 96% with k=2.

음식물쓰레기 관리의 최적화 방안 연구 : 창원, 마산, 진해시를 중심으로 Focused on Changwon, Masan, Jinhae City

이명희,박증석,김종오,백병천 國立 麗水大學校 環境問題硏究所 1998 環境硏究論文集 Vol.1 No.-

Limited landfill area and finance as well as a huge generation of waste, have called for systematic approaches towards potential cost savings. In this study, the management system of food wastes generated from the residential and commercial sources was considered in three citied; Changwon, Masan, and Jinhae city. Total thirteen alternatives were established and compared by applying the WRAP (Waste Resource Allocation Program). The following results were obtained: 1. While relatively small amounts were generated form the commercial sources such as cafeteria, restaurants, and market facilities, almost 80% of food wastes were generated from the residential sources. 2. Unit costs for food waste management in three cities were different according to their present situation, and the highest cost appeared in Jinhae city due to the most expensive construction of coastal landfill site. 3. Considering proper revenue, the whole conversion of food waste into animal feed was selected as the optimal alternative and represented 60% to 74% of management cost of the whole landfill alternative in all cities. Comparing the other alternatives, composting of food waste was more economical than the landfill alternative and the incineration was the most expensive alternative.

IMPROVED PERFORMANCE OF UPFLOW ANAEROBIC SLUDGE BLADGE BLANKET REACTOR (UASB) WITH MODIFIED GAS-SOLID SEPARATOR

PAIK,Byeong Cheon 여수대학교 1991 論文集 Vol.5 No.-

The effect of the modified gas-solid separator (GSS) on sludge wash-out and performance efficiency of UASB reactors treating concentrated complex soluble substrates were investigated. The modified GSS device prevented sludge washout significantly from the reactor not only in the start-up period but also at high organic loading rate. The maximum achievable loading rate and average COD removal rate with the conventional GSS device were 3.9kg COD ?? and 64%, respectively, whereas those of the modified GSS device were 5.7kg COD ?? and 65%, respectively. Long filaments bacteria were predominant on the surface of granular sludge developed in conventional reactor, whereas sludge in a reactor with the modified GSS device was composed mainly rod-shaped filamentous and cocci bacteria.

TREATMENT OF INDUSTRIAL WASTEWATERS WITH HIGH CONCENTRATION OF NITROGEN USING GAC-FBR

Paik, Byeong-Cheon,Kim, Kwangbog,Oh, Sae-Eun,Song, Young-Chae,Shin, Hang-Sik 영남대학교 환경문제연구소 2000 環境硏究 Vol.20 No.1

This study was carried out to investigate the treatability of industrial wastewaters with high concentration of nitrogen using granular activated carbon-fluidized bed reactor (GAC-FBR) and to establish operating technology for good performance of the process. The laboratory and pilot scale GAC-FBR process consisted of equalization tank, recycle tank, aerobic reactor for nitrification, and anoxic reactor for denitrification. Raw industrial wastewaters from mono-nitro-benzene (MNB) and aniline production processes of BASF Ltd. was used for the process and methanol was used as a carbon source for denitrification. The laboratory scale process was operated at the feed rate of 50.4 L/day, the hydraulic retention time (HRT) of 40 min in anoxic reactor and 110 min in aerobic reactor, effluent recycle ratio of 5:1. Average influent concentrations of nitrogen and COD were 1,472 mg/L and 1,231 mg/L, respectively. The total nitrogen removal efficiency for anoxic and aerobic reactors was in excess of 94% and the average COD removal efficiency was 95.3%. The pilot scale process was operated at feed rate of 5 m3/day, HRT of 3.4 hours in anoxic reactor and 24.5 hours in aerobic reacter, effluent recycle ratio of 10:1. Average influent concentration of nitrogen and COD were 1,621 mg/L and 1,378 mg/L, respectively. Total nitrogen and COD removal efficiencies were 98% and 93%, respectively. Aniline concentration of 6 mg/L in raw wastewater inhibited significantly the autotrophic nitrifying bacteria oxidizing ammonia to nitrite and nitrate. Effluent recycle ratio and alkalinity were important operating parameters in reduction of effluent nitrogen level.

Enhanced Effects of Nitrate Concentration on Toluene Removal form waste Gas Stream in Trickle Bed Biofilter

Paik, Byeong-Cheon,Kim, Hu-Soo 國立 麗水大學校 環境問題硏究所 2002 環境硏究論文集 Vol.5 No.-

본 연구에서는 석유화학 공장에서 배출되는 폐가스내 VOCs 중 Toluene의 효율적인 처리를 위한 생물여과장치의 운전에 관한 연구를 수행하였다. 선정된 두 종류의 담체(ABA-1, PC-1)로 채워진 두 개의 반응조에서 주입 공기량 25~40ℓ/min, 체류시간(EBRT) 40~23sec, 주입 영양물질 6ℓ/day로 운전하였으며, 이때 유기물부하량은 2.1~6.8kg COD/㎥·day 이었다. 전자수용체의 물질을 연구하기 위하여 주입 영양물질 중 질소 성분으로 질산성 질소이온(NO_(3)^(-)-N)을 이용하였으며, Toluene 농도가 160ppmv 즉, 유기물 부하율이 3.92kg COD/㎥·day으로 유입되는 각각 두 개의 반응조에서 COD:N ratio를 10:1로 주입하였을 때 최고 99.9%의 높은 처리효율을 나타내었다. ABA-1 담체로 채워진 생물여과반응조에서 체류시간(EBRT) 30sec, 주입 Toluene 농도 260ppmv에서 최고 94.4g toluene/bed㎥·hr의 제거율을 나타내었다. 두 개의 반응조에서 주입 영양물질중 질산 질소 이온(NO_(3)"-N) 농도가 증가함에 따라 bed당 제거되는 toluene의 양도 증가하는 경향을 보였다.