• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
• /
• pp.253-253
• /
• 2010

Rice straw was pretreated with aqueous ammonia in order to enhance enzyme digestibility. Soaking in ammonia aqueous (SAA) was conducted with 15% ammonia, at $60^{\circ}C$. for 24 h. Optimization of both saccharification conditions and enzyme loading of SAA rice straw was carried out. Especially enzyme loading test was performed using statistical method. Moreover proton beam irradiation (PBI) was also performed to overcome the problem which inhibit the enzyme digestibility at 1-25 kGy doses with 45 MeV of beam energy. Optimal condition for enzymatic saccharification was follows; pH 4.8, $50^{\circ}C$, 60 FPU of enzyme activity, 1:4 ratio of celluase and ${\beta}$-glucosidase. Also, optimal doses of PBI on rice straw and SAA-treated rice straw for efficient sugar recovery were found to be 3 kGy, respectively. When saccharification was performed with optimal condition, glucose conversion yield was 89% of theocratical maximum in 48 h, and 3 kGy of PBI was applied to SAA-treated rice straw, approximately 90% of the theoretical glucose yield was obtained in 12 h. The results of X-ray diffractometry (XRD) support the effect of both SAA and PBI on sugar recovery, and scanning electron microscopy (SEM) images unveiled the physical change of the rice straw surface since rugged rice straw surface was observed.

• KSBB Journal
• /
• 제14권3호
• /
• pp.358-364
• /
• 1999

참나무의 전처리에 과산화수소가 미치는 영향을 조사하였다. 반응온도는 $170^{\circ}C$이고 전처리에 사용된 반응용액은 암모니아, 황산 그리고 순수 물이었다.10% 암모니아용액을 사용한 경우 산을 사용하는 경우에 비해 리그닌 제거율은 55%로 상당히 높았지만 헤미셀룰로오스 회수율은 26%로 상당히 낮았다. 그래서 헤미셀룰로오스 회수율을 높이기 위해 암모니아 용액에 산화제인 과산화수소를 첨가하여 반응시켰는데 과산화수소 첨가량의 증가에 따라 리그닌 제거율과 헤미셀룰로오스 회수율의 증가는 크지 않았다. 그리고 과산화수소 첨가량의 증가에 따라 액상으로 용해된 당의 분해가 증가하여 전체 헤미셀룰로오스와 셀룰로오스의 물질수지에 문제가 있었다. 반응기에 주입된 과산화수소는 주로 반응기의 전반부에 충진된 기질과 반응하는 것으로 나타났다. 헤미셀룰로오스 회수율을 높이기 위해서는 알카리용액보다 산성용액에서 기질을 전처리하는 것이 필요하였고 산보다는 물을 사용하였을 때 과산화수소의 효과가 더 컸다.

• 한국수산과학회지
• /
• 제57권1호
• /
• pp.32-40
• /
• 2024

The aim of this research was to apply a method designed to derive the factors influencing total ammonia removal when operating an additional pretreatment system at Aquaponics. The Box-Behnken method, among response surface analysis methods was used to characterize and determine the optimal nitrification conditions when operating the pretreatment system. Among the mathematically and statistically calculated prediction equations, the total ammonia nitrogen concentration Y1 measured on day 8 was derived as Y₁=-195.8+2.23X₁+42.9X₂+47.5X₃+0.1856X₁²-1.380X₁X₂-1.770X₁X₃, and the time taken to reach the maximum total ammonia nitrogen concentration during the experiment period was derived as Y₂=271-5.04X₁+60.5X₂-64.8X₃+0.1654X₁²+6.54X₃²-0.600X₁X₃-9.00X₂X₃. The coefficients of determination of the regression models of Y₁ and Y₂ were 93.99% and 94.46%, respectively. The modified coefficients of determination were also high, at 89.48% and 88.91%, respectively. The prediction coefficients of determination of Y₁ and Y₂, were 70.68% and 62.11%, respectively, which was relatively lower than that of Y1, but still indicated a reliable prediction performance.

• Korean Chemical Engineering Research
• /
• 제52권1호
• /
• pp.45-51
• /
• 2014

본 연구는 농업 부산물인 옥수수대(corn stover)를 이용하여 묽은 황산법(DSA; dilute sulfuric acid)과 암모니아 침지법(SAA; soaking in aqueous ammonia) 그리고 암모니아 재순환 침출법(ARP; ammonia recycle percolation)을 비교하여 각 전처리법의 특징과 장단점을 분석하였고, 동시당화공동발효를 통한 에탄올 생산을 비교하였다. ARP, DSA, SAA를 이용하여 전처리된 고형물(3% 글루칸 투입)을 15 FPU/g-glucan, 30 CBU/g-glucan의 상업용 효소(Spezyme CP와 Novozyme 188;)와 E. coli KO11 균주(ATCC$^{(R)}$ 55124)를 이용하여 동시당화공동발효를 수행하였다. 전처리 후에 남은 고형물에 있는 당의 최대이론적 에탄올 수율은 각각 87, 90 그리고 78%였다. 이것은 전처리되지 않은 원래 옥수수대의 총 당량(글루칸 +자일란) 대비 각각 69, 58, 및 74%에 해당하는 것으로 SAA의 수율이 가장 높게 관찰되었다. 또한 전처리 당화액을 이용한 동시당화공동발효 실험결과는 DSA의 당화액이 발효균주에 대하여 가장 높은 독성을 나타내었고 ARP 전처리 당화액이 그 다음으로 저해효과가 큰 것으로 나타났다. 결국 SAA를 이용하여 전처리한 후 리그닌이 풍부한 당화액은 이용하지 않고 전처리된 고형물과 동시당화공동발효 공정을 이용한 에탄올 생산이 가장 간단하면서 경제적인 공정으로 제안되었다.

• Environmental Engineering Research
• /
• 제23권2호
• /
• pp.136-142
• /
• 2018

The river water source of Saidabad Surface Water Treatment Plant at Dhaka, Bangladesh, is deteriorated too much to be treated by conventional treatment process due to excessive ammonia pollution. In order to improve the raw water quality before it enters into the main treatment chain, a pilot study was conducted for pre-treatment of the raw water. The objective is to investigate the rate of reduction of ammonia using the Meteor pilot, a biological pretreatment system, which is a laboratory scale Moving Bed Biofilm Reactor with a nominal volume of hundred liters, filled with 50 L of Meteor 660 media. The reduction of ammonia was quite significant on average 73%, while the reduction of COD was in a range from 20 to 60%. The Meteor pilot was able to treat and nitrify the raw water and produce an effluent that respects the guarantee of ammonia < $4.0mg\;NH_3-N/L$ when the raw water ammonia concentration was < $15mg\;NH_3-N/L$. The study identified operating parameters necessary to achieve the desired goal of adequate ammonia removal. The study results would benefit a range of systems across the country by providing guidance on the design and operation of a biological pre-treatment system for ammonia removal.

• 한국염색가공학회지
• /
• 제27권1호
• /
• pp.96-104
• /
• 2015

This study examined the pretreatment effect, appropriate dyeing conditions, color fastness and functionality of cotton fabrics dyed with Zizania latifolia Turcz. Dye uptake was substantially increased by pretreatment and chitosan pretreatment was much more effective than tannic acid pretreatment. Optimal dyeing conditions were colorant concentration of 100%, dyeing temperature of $100^{\circ}C$, dyeing time of 80 minutes and dyebath pH of 5.5. Color fastness of chitosan pretreatment and dyed cotton to washing, rubbing, perspiration and light was 4, 5, 3-4(acidic), 3(alkaline) and 3 respectively. Color fastness of tannic acid pretreatment and dyed cotton to washing, rubbing, perspiration and light was 4, 5, 3-4(acidic), 4-5(alkaline) and 4 respectively. Deodorization rates of ammonia(NH3) were 99.9% in both cases. UV protection rate were 98.3% of UV-A and 98.5% of UV-B in case of chitosan pretreatment. UV protection rate were 98.2% of UV-A and 98.5% of UV-B in case of tannic acid pretreatment. UV protection factor(UPF) was 50+ in both cases. Reduction rate of Staphyloccus aureus were 99.9% in both cases. Therefore Zizania latifolia Turcz. could be used a new functional colorant.

• 한국전기전자재료학회논문지
• /
• 제23권5호
• /
• pp.418-423
• /
• 2010

Carbon nanotubes (CNTs) were synthesized by Fe-catalytic chemical vapor deposition (CVD) method about $800^{\circ}C$. The influence of process parameters such as pretreatment conditions, gas flow ratio, processing time, etc on the growth of CNTs was investigated by field emission scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. Ammonia was added to acetylene source gas before and during the CNT growth. Different types of CNTs formed depending upon the processing condition. It was found that ammonia prevented amorphous carbons from adsorbing to the outer wall of CNT, resulting in purification of CNTs during CNT growth.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 춘계학술발표대회
• /
• pp.459-462
• /
• 2000

The pretreatment of used newspaper for the enzymatic digestion preprocess was performed on a percolation reactor and a batch reactor. The test condition of percolation process was $170^{circ}C$, 60min, 1 mL/min, and 400psi, that of batch was $40^{circ}C$, 3hr. and latm Reaction solutions used in pretreatment process were aqueous ammonia, sulfuric acid, water, and hydrogen-peroxide as an oxidizing agent. As a result, the effect of pretreatment was similar to batch and percolation process, but the yield of enzymatic hydrolysis was higher in batch than percolation. This batch pretreatment enhanced enzymatic hydrolysis rate and increased glucose yield from about 15 to 20%. The inhibition factors influenced the rate of enzymatic hydrolysis was investigated, and the ink contented newspaper was the major factor.

• Journal of the Korean Wood Science and Technology
• /
• 제37권4호
• /
• pp.381-387
• /
• 2009

본 연구는 암모니아수 침지 처리가 옥수수대의 화학 조성과 효소당화 특성에 미치는 영향에 대하여 연구한 것이다. 암모니아수 침지에서 처리 온도와 시간이 본 연구에서 주요 변수였다. 무 처리 분말과 침지 처리 분말의 전체 조성 분석과 탄수화물 조성 분석 결과, 3가지 다른 수준의 암모니아수 침지 조건($140^{\circ}C$ - 1 h, $90^{\circ}C$ - 16h 및 $50^{\circ}C$ - 6일)에서 고온 단기간 처리가 더 많은 양의 자이란과 리그닌을 용출시켰다. 암모니아 침지에 의한 자일란과 리그닌 용출 제거 효과가 고온 침지 처리 된 옥수수 줄기 분말에서 상업용 셀룰라아제를 사용하는 셀룰로오스와 자이란의 효소 당화를 촉진시켰다.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
• /
• pp.418-421
• /
• 2009

Effects of aqueous ammonia soaking to three annual plants (hemp woody core, tobacco stalk and corn stover) awere investigated to focus on the enzymatic saccharification characteristics change by this treatment. At two different levels of treatment ($90^{\circ}C$-16 h and $45^{\circ}C$-6 days), higher temperature treatment led to more enzymatic saccharification of cellulose to glucose by commercial cellulase mixtures (Celluclast 1.5L and Novozym 342 from Novozyme Korea). Difference among annual plants were significant. corn stover was the best response to enzymatic saccharification of cellulose and xylan by comercial enzymes all treatment conditions but tobacco stalk was the worst response to all of them. chemical composition or physical structure difference may brought this difference.