• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.981-987
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• 2000

Upflow anaerobic sludge blanket(UASB) reactor was operated for treating swine wastewater containing high ammonia nitrogen to assess their performance and toxicity of free ammonia concentration. In the reactor, chemical oxygen demand(COD) removed about 70% at $2.6kgCOD/m^3.day$ of organic loading rate(OLR) and 3 days of hydraulic retention time (HRT), while it was decreased when OLR and HRT was maintained $7kg\;COD/m^3.day$ and 2 days, respectively. Also UASB reactor was evaluated the activity of methane producing bacteria(MPB) according to change of free ammonia concentrations, MPB activity of applied sludge in the 500 and $1000mg-N/{\ell}$ of free ammonia concentration was inhibited by 4% and 40%, respectively. This clearly showed that free ammonia concentration less than $500mg-N/{\ell}$ showed no inhibition to MPB in anaerobic treatment of organics, UASB reactor was stabilized easily less than $1000mgVSS/{\ell}$ due to degradation of organic solids by the high activities of anaerobes.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.367-370
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• 2003

This study was carried out to investigate the possibility for reuse of solid organic wastes such as saccharified newspapers and boxes by two-phase anaerobic fermentation system. When 15g of newspaper and box wastes were digested for 24 days by batch fermentation, tCOD removal rate were found to be 60.9 and 62.4%, respectively. During this period, the amounts of biogas produced were 6.95 and 6.43L. The removal efficiencies of total solid were 34.8 and 33.4%, and those of volatile solid were 40.0 and 39.2%, respectively. That pH was around 7.5 after 20-days operation means methane fermentation is well advanced. In case of semicontinuous reaction, tCOD removal efficiencies of newspaper and box wastes were 64.7 and 65.0%, respectively for 14-days operation. It has been shown that each of the average biogas amounts produced after 25 days operation (stabilization stage for methane fermentation) was 0.31 and 0.30L/g dry wt./day, respectively, and each methane contents was 57.3 and 56.2%, respectively. After the reaction continued for 25 days, pHs in the anaerobic acidogenic and methanogenic fermenters were shown to be 5.0 and 7.5, respectively.

• KSBB Journal
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• v.18 no.4
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• pp.318-323
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• 2003

This study was carried out to investigate the possibility of reusing newspaper or paperbox waste by methane fermentation. When 15 g of newspaper and box wastes were digested separately for 24 days by batch fermentation, the amount of total organic acids produced were 2461 and 4978 mg/L, respectively. The tCOD removal rates were found to be 60.9 and 62.4%, respectively. In addition, the removal efficiencies of total solid were 34.8 and 33.4%, and those of volatile solid were 40.0 and 39.2%, respectively. During this period, the amounts of biogas produced were 6.95 and 6.43 L. In a semicontinuous reaction, tCOD removal efficiencies for newspaper and box wastes were 64.7 and 65.0%, respectively, after 14 days of digestion. After 25 days, which were needed to stabilize the methane fermentation, the amounts of biogas produced daily were 0.31 and 0.30 L/g.dry wt, respectively. Methane contents were 57.3 and 56.2%, respectively, and the pHs in the anaerobic acidogenic and methanogenic fermenters were 5.0 and 7.5, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.895-902
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• 2011

Objective of this research was to investigate the characteristics of biogas production in anaerobic digestion reactor with different mixing ratio of food waste and swine manure. It was observed that the highest removal efficiency of organic material was 80% at 60 : 40 of mixing ratio (livestock manure : food waste). And also biogas yield was varied due to different mixing ratio of them. The cumulative biogas yield was highest at 60 : 40 of mixing rate (livestock manure : food waste). For use of the liquefied fertilizer as effluent from anaerobic digester, it was the limited ratio for 30% of co-digested food waste based on its salt content.

• Applied Biological Chemistry
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• v.22 no.1
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• pp.58-63
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• 1979

The solvent extracting of the tobacco has been carried out in order to find out any effects for the removal and/or reduction of nicotine from tobacco without affecting the tobacco flavor. We have now completed the physico-chemical characterization of the solvent untreated/treated tobaccos and 2) the contents of the tar and nicotine in the smoke. The results obtained ate like followings; 1. 3% alcohol extraction reduced the total nitrogen content for the Bright by 36.4%. However, it could not reduce the sugar content. 2. Nicotine content in tobacco leaves was inversely proportional to the dipping time Essentially same results were obtained in anacidic solution and even in a solution containing both alkali and acid. 3. Derivative thermogravimetric(DTG) curves indicated test extraction was effective by removing tobacco leaf components which could decompose or volatilize between the temperature of $150^{\circ}C\;and\;350^{\circ}C$. 4. 3% alcohol extracted leaf have the substantial improvements as following; (1) bulk filling power of 10% and 24% for Burley and Bright tobacco, respectively, (2) combustibility shortening of about 3 minute and 2 minute for Burley and Bright tobaccos, respectively, (3) reduction ratio(%) of nicotine was found to be shout 61.5% and 54.5% for Burley and Bright tobacco, respectively, (4) reduction ratio (%) of tar was obtained to he about 25% and 15% for Burley and Bright tobacco, respectively.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.527-532
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• 2001

Dry etching of copper film using $O_2$ plasma and H(hfac) has been investigated. A one-step process consisting of copper film oxidation with an $O_2$ plasma and the removal of surface copper oxide by the reaction with H(hfac) to form volatile Cu(hfac)$_2$ and $H_2O$ was carried but. The etching rate of Cu in the range from 50 to 700 /min was obtained depending on the substrate temperature, the H(hfac)/O$_2$ flow rate ratio, and the plasma power. The copper film etch rate increased with increasing RF power at the temperatures higher than 215$^{\circ}C$. The optimum H(hfac)/O$_2$ flow rate ratio was 1:1, suggesting that the oxidation process and the reaction with H(hfac) should be in balance. Cu patterning using a Ti mask was performed at a flow rate ratio of 1:1 on 25$0^{\circ}C$\ulcorner and an isotropic etching profile with a taper slope of 30$^{\circ}$was obtained. Cu dry patterning with a tapered angle which is necessary for the advanced high resolution large area thin film transistor liquid-crystal displays was thus successfully obtained from one step process by manipulating the substrate temperature, RF power, and flow rate ratio.

• Journal of Soil and Groundwater Environment
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• v.14 no.5
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• pp.10-17
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• 2009

Bioremediation has been applied as a proven technology in remediation of TPH contaminated soil. However, the efficiency of biodegradation is dependent on temperature as microbial activity is depressed at lower temperature ranges ($30^{\circ}C{\sim}80^{\circ}C$). The objective of this study was to develop microbes with enhanced activities at the stated temperature conditions and to evaluate the remediation effectiveness of these microbes in TPH contaminated soil. Experiments were conducted to isolate hydrocarbon degradable microbial consortia cultured under different temperature conditions. It was found that there were 5 strains of mesophilic ($30^{\circ}C$) and 3 strains of psychrophilic ($80^{\circ}C$) microbes. The TPH concentration was reduced from 4,044 mg/kg to 1,084 mg/kg, (73.2%) in 10 days by using mesophilic microbial consortia and from 5,427 mg/kg to 1,756 (67.6%) in 50 days with psychrophilic microbial consortia in laboratory cultures under controlled conditions. This rate determination excluded physical degradation such as venting and dilution. A field study was then performed to examine the feasibility of applying these microbes in the land-farming process. In this case, 87.1% of the 2,560 mg/kg TPH contaminated soil was degraded in 56 days. The biodegradation rate coefficient (k) was $0.0374\;day^{-1}$. Findings of this study provide viable options for applying microbes for bioremediation of TPH in lower temperature conditions.

• Journal of Soil and Groundwater Environment
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• v.10 no.2
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• pp.35-43
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• 2005

Bioslurping combines the three remedial approaches of bioventing, vacuum-enhanced free-product recovery, and soil vapor extraction. Bioslurping is less effective in tight (low-permeability) soils. The greatest limitation to air permeability is excessive soil moisture. Optimum soil moisture is very soil-specific. Too much moisture can reduce air permeability of the soil and decrease its oxygen transfer capability. Too little moisture will inhibit microbial activity. So Modified Fenton reaction as chemical treatment which can overcome the weakness of Bioslurping was experimented for simultaneous treatment. Although the diesel removal efficiency of SVE process increased in proportion to applied vacuum pressure, SVE process was difficulty to remediation quickly semi- or non-volatile compounds absorbed soil strongly. And SVE process had variation of efficiency with distance from the extraction well and depth a air flow form of hemisphere centering around the well. Below 0.1 % hydrogen peroxide shows the potential of using hydrogen peroxide as oxygen source but the co-oxidation of chemical and biological treatment was impossible because of the low efficiency of Modified Fenton reaction at 0.1 % (wt) hydrogen peroxide. NTA was more efficiency than EDTA as chelating agent and diesel removal efficiency of Modified Fenton reaction increased in proportion to hydrogen peroxide concentration. Hexadecane as typical aliphatic compound was removed less than Toluene as aromatic compound because of its structural stability in Modified Fenton reaction. What minimum 10% hydrogen peroxide concentration has good remediation efficiency of diesel contaminated groundwater may show the potential use of Modified Fenton reaction after bioslurping treatment.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.3
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• pp.91-98
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• 2017

The purpose of this study is to provide a design and operation technical guideline for meeting the appropriate design criteria to bio-gasification facilities treating organic wastes. 9 anaerobic digestion facilities which is normally operated during the field survey and 14 livestock manure farms were selected for precision investigation. the physicochemical analysis was performed on the moisture and organic contents, nutrients composition (carbohydrate, fat, protein), volatile fatty acids (VFAs), and nitrogen, etc. Volatile solids (VS) of organic wastes brought into the bio-gasification facilities were 2.81 % (animal manure only) and 5.92 % (animal manure+food waste), respectively. Total solids (TS) reults of samples from livestock farms were 5.6 % in piglets and 11~13 % in other kinds of breeding pigs. The actual methane yield based on nutrients contents was estimated to $0.36Sm^3CH_4/kgVS$ which is equivalent to 72 % of theoretical methane yield value. The optimum mixing ratio depending on the effect of the combined bio-gasification was obtained through the continuous stirred-tank reactor (CSTR) which is operated at different mixing ratio of swine manure and food waste leachate. The range of swine manure and food waste leachate from 60:40 to 40:60 were adequate to the appropriate conditions of anaerobic digestion; less than 100 gTS/, more than alkalinity of 1 gCaCO3/L, C/N ratio 12.0~30.0, etc.

• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.211-218
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• 2007

This study was carried out to develop the technique for manufacturing activated carbon from livestock manure and to analyse it's odor absorptiveness. Each of layer manure(LM), litter from broiler house(BL) and litter from dairy barn(DL), compost from layer manure(LC) and pig manure(PC), and coconut shell(CS) was used as a raw material. Activated carbon by grinding the raw material, adding the coal tar as a binder, palletizing, drying, heating with $N_2$ gas at $400^{\circ}C$ for 1 hour, activating by reaction with steam at a temperature of $750^{\circ}C$ for 1 hour. Moisture contents of raw material was 44.9% in layer compost, 71.9% in layer manure, 24.4% in broiler litter, 47% in pig manure compost and 33.9% in dairy litter. Volatile matter in layer compost, layer manure, broiler litter, pig manure compost and dairy litter was 18.8%, 31.0%, 49.8%, 22.3% and 11.6%, respectively. Surface area(BET) of activated carbon from layer compost, layer manure, broiler litter, pig manure compost, dairy litter and coconut shell was 259.8, 209.8, 63.5, 442.3, 812.9 and $1,040\;m^2/g$, respectively. Activated carbon made by livestock manure or litter were examined with scanning electron microscope, and micropore was a type of sponge like particles honeycombed with chambers. Pore size of activated carbon was ranged from 0.39 to $5.02\;{\AA}$, but coconut shell was $0.30\;{\AA}$. Iodine absorptiveness of activated carbon from livestock manure was $530{\sim}580mg/g$. But activated carbon made by coconut shell was 1000 mg/g. Each activated carbon could absorb odor compound very well. Absorptiveness of activated carbon from layer manure for hydrogen sulfide and trimethyl amino was 74.5% and 73.9% at the accumulated flux of 60,000 ml, but, in the case of ammonia was only 15.2% at the accumulated flux of 10,000 ml