• Applied Chemistry for Engineering
• /
• v.18 no.2
• /
• pp.162-167
• /
• 2007

Hydrogen production and its dynamics were investigated in the continuous anaerobic digestion process using Clostridium beijerinckii Donker 1926. In this work, glucose was used as a substrate and hydraulic retention times (HRT) were 0.5, 0.25 or 0.125 day. The removal efficiency of carbohydrate was over 99% under all of HRT conditions. As HRT was shorter, COD removal efficiency became lower while hydrogen content in the total gas and hydrogen production rate became higher. The cell growth yield and hydrogen production yield were 0.27 g-VSS/g-glucose and 0.26 L/g-glucose, respectively, at the steady state. It is expected that the microorganism is able to produce hydrogen when used in the wastewater treatment containing carbohydrate such as glucose. Also, the results in this study could be applied to the actual hydrogen gas production, a promising alternative energy.

• Korean Journal of Environmental Agriculture
• /
• v.21 no.4
• /
• pp.248-254
• /
• 2002

This study was carried out to evaluate the proper application amount of anaerobic digestion waste water and the environmental influence on rice. The waste water collected after methane fermentation process of pig manure was used as a liquid manure. Liquid manure 100%+chemical fertilizer 30%(LM 100%+CF 30) treatment was the most favorable at all growth stages of rice. The LM 100%+CF 30% treatment was applied to 100% amount of liquid manure which was correspond to the same amount of nitrogen for the standard application amount on rice, with adding 30% amount of chemical fertilizer(urea) at tillering stage. The yields of rice in the treatments of 100%(LM 100%) and 150% amount(LM 150%) of liquid manure were similar or a little higher than NPK treatment but LM 100%+CF 30% treatment was less than the NPK treatment due to the increase of straw weight and plant lodging. In periodic changes of the $NH_4-N$ and $NO_3-N$ contents, the LM 70%+CF 30% treatment in paddy soil was the highest in all treatments. The NPK and the LM 100% treatments in irrigation water quality were higher than other treatments. In infiltration water quality, $NH_4-N$ content was leached out much in the LM 150% treatment and $NO_3-N$ content was in the LM 100%+CF 30% treatment. The proper application amount of anaerobic digestion waste water as a liquid manure must be to analyse the nitrogen content of the waste water and to apply the same amount of nitrogen for the standard application amount on rice.

• Korean Journal of Environmental Agriculture
• /
• v.21 no.4
• /
• pp.255-260
• /
• 2002

This study was conducted to evaluate the effect of the proper application level of anaerobic digestion waste water on rice. The waste water was from methane fermentation of pig manure to use as a liquid manure. The mixture treatment of 70% liquid manure and 30% chemical fertilizer (LM 70%+CF 30%) and 100% liquid manure (LM 100%) treatment were higher number of tiller than other treatments at the both tillering and heading stages of rice. The yields of LM 70%+CF 30% and LM 100% treatments were a little higher than that of NPK treatment, but the mixture treatment of 50% liquid manure and 50% chemical fertilizer (LM 50%+CF 50%) was a little lower yield than NPK treatment. The periodic changes of the $NH_4-N$ and $NO_3-N$ contents of the NPK and the LM 50%+CF 50% treatments in paddy soil were a little higher than those of other treatments at the early stage of rice. The $NH_4-N$ contents of NPK and the LM 50%+CF 50% treatments in irrigation water quality were higher than those of other treatments, however there was no difference in $NO_3-N$ content among the treatments. The $NH_4-N$ and $NO_3-N$ contents of non fertilizer treatment in infiltration water quality were leached a little higher than those of other treatments. It may be due to poor growth of rice following to reduce the nutrient uptake by rice and to increase relatively the nutrient leaching to the ground water. The proper application level of anaerobic digestion waste water as a liquid manure could be suggested to apply LM 70%+CF 30%. All treatments were the same amount of nitrogen content for the standard application amount on rice.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.4 no.1
• /
• pp.53-60
• /
• 1996

This study was carried out to investigate the effects on the growth of soybean and carrot, and these uptake of inorganic components, after the application of sewage sludge disgested anaerobically at wastewater treatment plant for about 25 days. With the application of the sludge, some chemical properties of soil was improved and heavy metals, as Pb, Cd, Cr, As and Hg, in finally harvested crops were not detected. With an increase in the application of the sludge, the uptake of N, P, K, and Ca in carrot was increased and also in the yield of two crops. In related to the quality of carrot, however, application of unmatured sewage sludge showed to deteriorate the visual quality with an irregularity of carrot's surface, despite of the increase of ${\beta}$-carotene concentration with an increased application of the sludge. The results suggest that for a land application of sewage sludge it should be necessarily stabilized by means such as composting.

• Journal of Life Science
• /
• v.20 no.10
• /
• pp.1468-1475
• /
• 2010

Sulfate reduction rates (SRR) using $^{35}SO_4^{-2}$, sulfide producing rates (SPR) using gas chromatography, the number of sulfate reducing bacteria (SRB) using the most probable number (MPN) method, and soil components (moisture, ammonium, total nitrogen, total organic carbon, total carbon, total inorganic phosphorus, total phosphorus, and sulfate) using standard methods in the organic/conventional rice paddy soils, cleaned/polluted reservoir soils, and cleaned/polluted foreshore soils were studied with the change of seasons. The average SRR was more related to the number of SRB and soil components (especially nitrogen and phosphorus) than sulfate concentration. SRR was also recorded to be highest in October soil samples. However, SPR was higher in foreshore soils containing a high concentration sulfate than in fresh water soils, and it was also recorded to be higher in the polluted areas than in clean areas. From these results, we can conclude that the SRR and SPR of anaerobic environments were affected by the number of SRB, soil components and temperature.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.5
• /
• pp.837-847
• /
• 2000

For the treatment of wastewaters generated from beer industry and petrochemical company with high organic and nitrogen contents, laboratory scale of A/O Pure-Oxygen Biofilm (POB) process was developed and studied by means of the comparative economic analysis with extended aeration process. When the wastewater of beer company was initially treated by the A/O POB process in the ranges of 70 to 150 mg TOC/L diluted with tap water, higher than 92% of TOC removal was accomplished in the all ranges. In case of petrochemical wastewater, the initial TOC removal was as low as 52%, though, it increased to 86% after 32 days of operation and also the TKN removal marked 71% after 27 days. Continuous high removal rates were monitored in both the TOC and TKN parameters during the experimental period. Due to the cost for PSA (Pressure Swing Adsorption) setting and biomass supporting media installation, the initial construction cost of A/O POB process was 2.9 times higher than that of extended aeration process. However, the advantages such as low sludge production, no need for sludge recycling and low energy consumption allow the A/O POB process to have 2.5 times lower operation and maintenance costs. Consequently, in the long term of operation, it is likely that A/O POB process would show higher performance as well as cost effectiveness compared to extended aeration process.

• KSBB Journal
• /
• v.17 no.3
• /
• pp.255-260
• /
• 2002

1,3-Propanediol as a bifunctional organic compound could be used in polymerization reactions producing polyesters and polyurethanes. Byproduct containing high concentration of glycerol from fat industry was used to produce 1,3-propanediol in lower production cost as well as waste treatment. In this study, various attempts were made to increase 1,3-propanediol production under different conditions using Klebsiella pneumoniae ATCC 15380. The conversion yield and byproduct formation were influenced significantly by the fermentation pH and temperature. The optimal glycerol and nitrogen concentration for 1,3-propanediol production were found to be 25 a/L and 1%(w/v), respectively. The formation of 1,3-propanediol was optimal at pH 6.0 and temperature $35^{\circ}C$. 1,3-Propanediol production from byproduct from 2.5% glycerol was lower than that of 2.5% commercial glycerol and amounted only to 9.84 a/L from byproduct, while to 12.13 a/L from commercial glycerol.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.23 no.2
• /
• pp.28-35
• /
• 2015

In this study, the experiment was carried out to produce methane by applying Semi-Continuous Leachate Recirculation Anaerobic Digestion System fed with source separated food waste from school cafeteria. There were two systems and each system consisted of a bioreactor and a liquid tank. Each bioreactor had a screen near the bottom of the reactor. 2.5L of separated liquid was transferred to the liquid tank for 30min each day by using a tubing pump and the liquid from the liquid tank was pumped to the bioreactor at the upper of the bioreactor as soon as the transfer was ended. Through this circulation, the liquid having high concentration of VFAs was supplied to the top of bioreactor. At the beginning of the experiment, food waste/inoculum anaerobic sludge volume ratio was 2:8 that is 9g VS/L of OLR(Organic Loading Rate). Feeding was conducted every two weeks. Experimental results showed that the contents of moisture, combustible matter, ash were 65.91%, 32.73%, and 1.36%, respectively. Two different food waste loading were studied. The average organic loading rates were 3.51g VS/d for System A and 3.86g VS/d for System B, respectively. The average produced methane based on food waste fed to bioreactor were observed as $6.30m^3CH_4/kgVS{\cdot}d$ for system A and $4.94m^3CH_4/kgVS{\cdot}d$ for System B, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.4
• /
• pp.1354-1360
• /
• 2010

The purpose of this study is to analyze the behavior of swine slurry wastewater from bogen, in the treatment of Aerobic Liquid-Composting treatment by Aerobic Liquid-Composting using a mixer and Micro Air Diffusion pH level was at the beginning and its rise was seemingly related to VFA. It appears that removal of BOD and COD are more effective by Aerobic than by Anaerobic. In terms of removal efficiency, it shows 70.9% of BOD and 39% of COD in M.A+Mix and 67.8% of BOD and 19% of COD in M.A. $NH_3-N$ decreases in all conditions, which is caused by both the characteristic of nitrogen and the rise of pH. $NO_3-N$ increases in all conditions. It is judged that the accumulation of $NO_3-N$ affects the reduction of the ratio of denitrification. In the result of the analysis of Manure in swine slurry of liquified fertilizer ingredients, content of Manure in swine slurry of liquified fertilizer ingredients in aerobic conditions (M.A+Mix) is higher than anaerobic conditions.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.36 no.2
• /
• pp.237-244
• /
• 2009

When the symptom of periapical infection is not released by mechanical instrumentation. anti-microbial agents including antibiosis become necessary in order to remove microorganisms from the root canal. Since anti-microbial agents of natural origins are currently popular, more natural remedies are being sought out. As it turns out, it is well known isothiocyanates (ITCs) in horseradish root extract have anti-microbial activity from many studies. In this research, anti-microbial effects of horseradish root extract and chlorhexidine, a typical anti-microbial agent, were investigated and compared against two kinds of obligate anaerobes. Fusobacterium nucleatum and Prevotella nigrescens, that are often discovered in infected root canal, and Clostridium perfringens, which is resistant to antibiotics and frequently used as a control strain for antibacterial studies 1. The MIC and MBC of horseradish root extract were ranged from 87 to 470 ppm and from 156 to 625 ppm against three kinds of obligate anaerobes, respectively. Horseradish root extract showed the strongest anti-bacterial activity (MBC, 156 ppm) against F. nucleatum and also showed anti-bacterial activity against antibiotic resistant obligate anaerobes. C. perfringens. 2. The MIC and MBC of chlorhexidine were ranged from 3.12 to 6.25 ppm and 10.94 ppm against three kinds of obligate anaerobes, respectively. 3. The MIC with 87-470 ppm of horseradish root exact has the same growth inhibiting effect as the one of 3.12-6.25 ppm of chlorhexidine. Likewise, the MBC with 156-625 ppm of horseradish has the similar bactericidal effect as 10.94 ppm of chlorhexidine.