혐기성 소화반응의 이론적 고찰

장덕 대한상하수도학회 1989 상하수도학회지 Vol.3 No.1

운적회분식 활성슬럿지법에서의 C/N 비에 따른 질소거동

장덕,이준걸 대한상하수도학회 1987 상하수도학회지 Vol.1 No.2

Laboratory experiments including steady-state operation and track study were carried out in order to investigate the effect of C/N ratio on the removal of organic matter and fate of nitrogen in SBR activated sludge process. Organic matter, ammonia nitrogen and TKN removal efficiencies increased with increasing C/N ratio. Conversion rate of ammonia nitrogen that was converted to nitrate and nitrite increased with increasing C/N ratio, while total amount of conversion increased with decreasing C/N ratio. It was also found that total amount of ammonia nitrogen converted per unit weight of microorganism decreased with increasing C/N ratio. Denitrification commenced as soon as air supply was stopped and occurred very effectively during fill period. Denitrification rates were above 80 percent for all C/N ratios while total amount of oxidized nitrogen denitrified decreased with increasing C/N ratio.

하수처리시설 설계 및 운영에서의 컴퓨터 활용

장덕,Jang, Deok 한국상하수도협회 1993 水道 Vol.59 No.-

혐기성소화-온도영향

장덕,Jang, Deok 한국상하수도협회 1987 水道 Vol.38 No.-

제 2 회 학술발표회 및 세미나 : 중 , 고온 소화 슬러지의 탈수성 비교 연구

장덕,김선집 대한상하수도학회 1988 학술발표회 및 세미나 Vol.1988 No.-

Performance response and recovery of temporal and spatial phase separated process for nutrients removal in short-term shock loadings

장덕,최현섭,선우영,홍기호 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

This study was conducted to evaluate the stability and performance response under short-term hydraulic and organic shock load conditions in temporal and spatial phase separated process. The overall removals of BOD, TN, and TP declined slightly despite the hydraulic shock loading, and rapid recovery could be observed again after four cycles of 16 h. It seems that rapid recovery may be achieved by the unique characteristics of the system operated in a fed-batch manner. The effect of shock load on nitrogen removal due to increment of flow rate was higher than that of phosphorus, because of the insufficient reaction time for the nitrification and denitrification. After the organic shock, however, recovery time for phosphorus removal was needed rather than that of organics and nitrogen, because the overload to micro organisms related to the phosphorus release is attained by short-term organic shock loading.

유로변경 간헐폭기식 침전지내장형 산화구시스템에 의한 하수의 탈질?탈인

장덕,홍기호,허준무,한상배 대한상하수도학회 2003 상하수도학회지 Vol.17 No.1

Phased isolation intrachannel clarifier ditch system devised in this study is an innovative biological nutrient removal system employing two ditches with intrachannel clarifiers and eliminating external pre-anaerobic reactors and recycle of sludge and treated effluent. The performances of the system were evaluated through a long term pilot-scale experiments. The system operated at hydraulic retention times of 10∼21hours and solids retention times of 16∼36days showed removals of biochemical oxygen demand, total nitrogen, and total phosphorus in the range of 90∼99%, 64∼93%, and 63∼98%, respectively, at the mixed liquor temperature above 10 . The solids retention time played a relatively important role among the operational parameters of the system. As the solids retention time became longer, the effluent total nitrogen decreased dramatically, whereas the effluent total phosphorus increased. Optimal system operating strategies maximizing phosphorus release and its uptake as well as nitrification and denitrification satisfying both the best nitrogen and phosphorus removals included hydraulic retention times ranged 10∼14hours and solids retention times ranged 20∼25days. The phase separation in a cycle maximizing the performance of the system was completely accomplished by scheduling of alternating flow and intermittent aeration in a simplified process scheme. Especially, temporal phase separation for phosphorus release without additional anaerobic reactor was successfully accomplished during anaerobic period without any nitrate interference and carbon-limiting. The phased isolation ditch system with intrachannel clarifier developed in this study was, therefore, believed to be a simplified and improved option to solve the problems in the existing biological nutrient removal technologies.

Pre-denitrification and Post-nitrification in an Integrated Anaerobic/Aerobic Filter System for Advanced Treatment of Municipal Wastewater

장덕,Seong Cheol Seo,홍기호 한국공업화학회 2004 Journal of Industrial and Engineering Chemistry Vol.10 No.3

혐기성소화(嫌氣性消化)의 동력학(動力學) : 중온(中溫) 및 고온혐기성소화(高溫嫌氣性消化)의 비교연구(比較?究)

장덕,정태학,Chang, Duk,Chung, Tai Hak 대한토목학회 1987 대한토목학회논문집 Vol.7 No.3

중온소화(中溫消化)와 고온소화(高溫消化)의 차이점을 보다 명확히 규명하기 위하여 소화(消化)의 정지(停止)를 포함하는 폭넓은 실험을 행하였다. 연구결과, 정상소화(正常消化)와 소화조해(消化阻害)를 구분짓는 한계체류시간(限界滯留時間)이 존재하여, 중온(中溫)에서는 10일(日), 고온(高溫)에서는 5일(日)부근이었고 그 이하(以下)의 체류시간(滯留時間)에서는 소화(消化)의 조해(阻害)가 급격하게 발생하였는데 고온(高溫)에 비하여 중온(中溫)에서의 조해(阻害)정도가 매우 컸다. 중온소화(中溫消化)의 한계체류시간이상(限界滯留時間以上)에서는 소화(消化)상태가 거의 유사하였으나, 그이하(以下)의 체류시간(滯留時間)에서는 고온소화(高溫消化)가 월등히 양호(良好)하였으며, 고온(高溫)에서는 중온(中溫)에 비하여 소화(消化)슬러지발생량(發生量)이 감소하는 동시에 소화(消化)슬러지의 침강속도(沈降速度)가 크게 증가하고 여과비저항(濾過比抵抗)은 감소하였다. 한편 반응속도(反應速度)는 소화(消化)에 마치는 온도(溫度)와 체류시간(滯留時間)의 영향을 나타내는 데 유효하였다. 또한 온도(溫度)에 관계없이 반응속도(反應速度)가 증가함에 따라 가스발생속도(發生速度)가 선형적(線形的)으로 증가하였고 그 상관관계(相關關係)는 중온(中溫)과 고온(高溫)에서 거의 일치하였다. Comprehensive laboratory experiments including digestion failures were conducted to identify differences between mesophilic and thermophilic digestion. Critical HRT was found to be near 10days for mesophilic and near 5days for thermophilic digestion. Inhibition occurred rapidly when operated below critical HRT. However, inhibition at mesophilic condition was much greater than that at thermophilic condition. Although digester performances were similar above critical HRT of mesophilic digestion, thermophilic digestion was considerably advantageous below this HRT. Thermophilic digestion produced smaller amount of sludges which had significantly higher settling velocity and lower specific resistance. Reaction rates also clearly demonstrated temperature and HRT effects on digestion. It was also found that gas production rates increased linearly with increasing reaction rates regardless of temperature and their relationships were almost identical at mesophilic and thermophilic temperature.

혐기성소화조(嫌氣性消和槽)의 고온(高溫)에로의 전환(轉換)

장덕,정태학,Chang, Duk,Chung, Tai Hak 대한토목학회 1986 대한토목학회논문집 Vol.6 No.4

인공(人工)슬러지를 이용하여 혐기성중온소화(嫌氣性中溫消和)의 고온소화(高溫消化)에로의 전환방법(轉換方法)에 대하여 연구하였다. 부하(負荷)를 계속하며 온도증가율(溫度增加率) 2, 1 및 $0.5^{\circ}C/day$로 온도를 상승시킨 결과, 온도증가율(溫度增加率) 이 클수록 메탄발효(醱酵)가 급속하게 악화되었으며, 세경우 모두 고온(高溫)에 도달하였을 때는 메탄발효(醱酵)가 중지되고 산발효(酸醱酵)만이 일어났다. 이러한 산발효상태(酸醱酵狀態)에서 부하(負荷)를 끊고 중화(中和)를 행한 후 6개월간(個月間)의 휴지기간중(休止期間中)에도 메탄발효(醱酵)는 이루어지지 않았다. 이로부터 메탄생성균(生成菌) 온도충격(溫度衝擊)의 크기에 비례하여 급속하게 활성(活性)을 잃는 반면 산생성균(酸生性菌)은 영향을 덜 받아 고온하(高溫下)에서 적응될 수 있다고 판단할 수 있다. 반면에 무부하상태하(無負荷狀態下)에서 온도(溫度)를 상승시켰을 때, 정상적(正常的)인 고온소화(高溫消化)가, 온도증가율(溫度增加率) $1^{\circ}C/day$의 경우 고온(高溫)에 도달한 후 1일(日)의 휴지기간(休止期間)으로도 가능하였고 일시(一時)에 상승시킨 경우도 20일간(日間) 휴지기간(休止期間)으로 가능하였다. 따라서 고온(高溫)에로의 전환(轉換)은 무부하상태하(無負荷狀態下)에서 용이(容易)함을 알 수 있는 동시에, 온도증가율(溫度增加率)이 작은 경우 고온(高溫)도달 후 짧은 휴지기간(休止期間)으로 전환(轉換)이 가능하며, 온도증가율(溫度增加率)이 매우 커서 급격한 온도충격(溫度衝擊)이 발생하는 경우에도 메탄생성균(生成菌)이 산생성균(酸生性菌)과 균형을 이루기에 충분한 휴지기간(休止期間)이 주어지면 고온소화(高溫消化)에로의 전환(轉換)이 가능함을 알 수 있다. 한편 산발효상태(酸醱酵狀態)의 고온소화조(高溫消化槽)에 중온소화(中溫消化)슬러지를 식종(植種)한 결과 신속하게 정상정(正常的)인 고온소화(高溫消化)가 이루어질 수 있었다. 따라서 중온소화(中溫消化)슬러지에 의한 식종(植種)은 고온소화(高溫消化)의 초기운전시(初期運轉時)나 정상정(正常的)인 소화(消化)의 정지시(停止時) 매우 유효(有效)한 전환(轉換) 및 회복방법(回復方法)이 될 수 있을 것이다. 또한 온도상승(溫度上昇) 및 중온(中溫)슬러지식종(植種)에 의한 정상정(正常的)인 고온소화결과(高溫消和結果)로부터 중온하(中溫下)에서도 상당량(相當量)의 고온균(高溫菌)이 존재하고 있음을 알 수 있다. Conversion of anaerobic mesophilic digestion to thermophilic range has been investigated using a synthetic sludge. When temperature was raised at a rate of 2, 1, and $0.5^{\circ}C$ per day with continuous feeding, a lower reaction rate was observed with a high rate of temperature change. Although methane fermentation ceased completely for an digesters at thermophilic temperature, acid fermentation continued. Methane fermentation was never achieved even with neutralization during 6 months of resting. The methane formers were completely inactivated by the temperature shock and accumulation of volatile acids due to continuous feeding, while the acid formers lost biological activity quickly, but gradually acclimated to a high temperature. When temperature was raised without feeding, successful thermophilic digestion was achieved with 1 day of resting at thermophilic temperature at a rate of $1^{\circ}C$ per day, and also achieved with 20 days of resting at a direct increase. Conversion to a thermophilic range is easily achieved with resting. A short period of resting is required at a low rate of temperature increase, while a long period of resting enough to balance methane formers with acid fermers makes a conversion possile when temperature is raised at a high rate. Soured thermophilic digesters were recovered after seeding of mesophilic sludges, and sludge seeding could be a good method of start-up, conversion, or recovery of a thermophilic digester. Significant amount of thermophiles seemed to be present in the mesophilic digesters.