• Title/Summary/Keyword: Slurry system

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Enhancing maintenance performance of tunnel drainage using vibration from polyvinylidene fluoride(PVDF) film (압전필름의 진동을 활용한 터널배수재 유지관리 성능 개선)

  • Xin, Zhen-Hua;Moon, Jun-Ho;Song, Young-Karb;Kim, Young-Uk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.1
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    • pp.822-826
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    • 2015
  • This study investigated the possible use of vibration from polyvinylidene fluoride(PVDF) film to enhance the performance of the deteriorated tunnel drainage due to physical/chemical clogging of the fine particles through a series of laboratory experiments. The test program was consisted of two different experiments, fundamental investigation and drainage model test. In the fundamental investigation, flow of clay slurry mixed with 50% water (freshwater and brine) on PVDF film with various frequencies was examined. In the model tests, slurry clogging to the woven fiber attached to drainage pipe and its reduction by vibration was investigated. Results of the experiment show that vibration from PVDF film enhances the drain performance significantly. Based upon the investigation, it gives an essential data that are needed for a potential use of hybrid drainage system with PVDF.

Emission Characteristics of Elemental Constituents in Fine Particulate Matter Using a Semi-continuous Measurement System (준 실시간 측정시스템을 이용한 미세입자 원소성분 배출특성 조사)

  • Park, Seung-Shik;Ondov, John M.
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.2
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    • pp.190-201
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    • 2010
  • Fine particulate matter < $1.8{\mu}m$ was collected as a slurry using the Semicontinuous Elements in Aerosol Sampler with time resolution of 30-min between May 23 and 27, 2002 at the Sydney Supersite, Florida, USA. Concentrations of 11 elements, i.e., Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, and Zn, in the collected slurry samples were determined off-line by simultaneous multi-element graphite furnace atomic absorption spectrometry. Temporal profiles of $SO_2$ and elemental concentrations combined with meteorological parameters such as wind direction and wind speed indicate that some transient events in their concentrations are highly correlated with the periods when the plume from an animal feed supplement processing facility influenced the Sydney sampling site. The peaking concentrations of the elemental species during the transient events varied clearly as the plume intensity varied, but the relative concentrations for As, Cr, Pb, and Zn with respect to Cd showed almost consistent values. During the transient events, metal concentrations increased by factors of >10~100 due to the influence of consistent plumes from an individual stationary source. Also the multi-variate air dispersion receptor model, which was previously developed by Park et al. (2005), was applied to ambient $SO_2$ and 8 elements (Al, As, Cd, Cr, Cu, Fe, Pb, and Zn) measurements between 20:00 May 23 and 09:30 May 24 when winds blew from between 70 and $85^{\circ}$, in which animal feed processing plant is situated, to determine emission and ambient source contributions rates of $SO_2$ and elements from one animal feed processing plant. Agreement between observed and predicted $SO_2$ concentrations was excellent (R of 0.99; and their ratio, $1.09{\pm}0.35$) when one emission source was used in the model. Average ratios of observed and predicted concentrations for As, Cd, Cr, Pb, and Zn varied from $0.83{\pm}0.26$ for Pb to $1.12{\pm}0.53$ for Cd.

Gasification of Coal-Petroleum Coke-Water Slurry in a 1 ton/d Entrained Flow Gasifier (1톤/일 분류층가스화기에서 석탄과 석유코크스 혼합 슬러리의 가스화특성)

  • Yoon, Sang Jun;Choi, Young-Chan;Hong, Jai-Chang;Ra, Ho Won;Lee, Jae Goo
    • Korean Chemical Engineering Research
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    • v.46 no.3
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    • pp.561-566
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    • 2008
  • Gasification plant using petroleum coke for refinery and power generation process is increased from considering petroleum coke as a valuable fuel. In this study, gasification of petroleum coke was performed to utilize petroleum coke and to develop essential technology using 1T/D coal gasification system. In case of petroleum coke gasification, because of lower reactivity, consumption of oxygen is higher than coal gasification. The calorific value of syngas from petroleum coke mixed with coal at a mass ratio of 1:1 shows about $6.7{\sim}7.2MJ/Nm^3$. Although carbon conversion could reach more than 92% according to oxygen amount, cold gas efficiency shows lower value than the case of coal. Therefore, it was shown that complemental study in burner design to atomize slurry droplet is required to elevate gasification performance of petroleum coke which has lower reactivity than coal.

Effect of Biofilm Formation on Soil Sorbed Naphthalene Degradation (Biofilm 생성이 토양흡착 나프탈렌 분해에 미치는 영향)

  • Li, Guang-Chun;Chung, Seon-Yong;Park, Jeong-Hun
    • Journal of Soil and Groundwater Environment
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    • v.14 no.6
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    • pp.45-52
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    • 2009
  • Naphthalene-degrading bacteria Pseudomonas aeruginosa CZ6 isolated from contaminated soil can adhere to crystal naphthalene and produce extracellular polymeric substance. LB, YM and MSM medium were used as culture mediums to investigate the formation of biofilm. Biofilm was developed the most in LB medium by Pseudomonas aeruginosa CZ6. In the culture, strain CZ6 growth was rarely affected by naphthalene concentration. Optimal culture condition was $30^{\circ}C$ and pH 7 at 0.10% substrate and 150 rpm shaking. The effect of culture medium on naphthalene degradation in the two soil slurry system was evaluated. The initial degradation rate of naphthalene was highest in the MSM medium of soil slurry. However, the sorbed naphthalene was rapidly degraded at the LB medium when naphthalene availability in liquid was limited. The results of this study suggest that biofilm formation and extracellular polymeric substance production increased bioavailability of soil sorbed naphthalene.

Effect of Abrasive Particles on Frictional Force and Abrasion in Chemical Mechanical Polishing(CMP) (CMP 연마입자의 마찰력과 연마율에 관한 영향)

  • Kim, Goo-Youn;Kim, Hyoung-Jae;Park, Boum-Young;Lee, Hyun-Seop;Park, Ki-Hyun;Jeong, Hae-Do
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.10
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    • pp.1049-1055
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    • 2004
  • Chemical Mechanical Polishing (CMP) is referred to as a three body tribological system, because it includes two solids in relative motion and the CMP slurry. On the assumption that the abrasives between the pad and the wafer could be a major reason not only for the friction force but also for material removal during polishing, the friction force generated during CMP process was investigated with the change of abrasive size and concentration of CMP slurry. The threshold point of average coefficient of friction (COF) with increase in abrasives concentration during interlayer dielectric (ILD) CMP was found experimentally and verified mathematically based on contact mechanics. The predictable models, Mode I (wafer is in contact with abrasives and pad) and Mode II (wafer is in contact with abrasives only), were proposed and used to explain the threshold point. The average COF value increased in the low abrasives concentration region which might be explained by Mode I. In contrast the average COF value decreased at high abrasives concentration which might be regarded to as Mode II. The threshold point observed seemed to be due to the transition from Mode I to Mode II. The tendency of threshold point with the variation of abrasive size was studied. The increase of particle radius could cause contact status to reach transition area faster. The correlation between COF and material removal rate was also investigated from the tribological and energetic point of view. Due to the energy loss by vibration of polishing equipment, COF value is not proportional to the material removal rate in this experiment.

Culture-Independent Analysis of Microbial Succession During Composting of Swine Slurry and Mushroom Cultural Wastes

  • Cho, Kye-Man;Lee, Sun-Mi;Math, Renukaradhya K.;Islam, Shah Md. Asraful;Kambiranda, Devaiah M.;Kim, Jong-Min;Yun, Myoung-Geun;Cho, Ji-Joong;Kim, Jong-Ok;Lee, Young-Han;Kim, Hoon;Yun, Han-Dae
    • Journal of Microbiology and Biotechnology
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    • v.18 no.12
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    • pp.1874-1883
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    • 2008
  • Bacterial diversity and the composition of individual communities during the composting process of swine and mushroom cultural wastes in a field-scale composter (Hazaka system) were examined using a PCR-based approach. The composting process was divided into six stages based on recorded temperature changes. Phylogenetic analysis of eighty 16S rRNA sequences from uncultured composting bacterial groups revealed the presence of representatives from three divisions, including plant pathogenic bacteria, high-molecule-degrading bacteria and spore-forming bacteria. The plant pathogen A. tumefaciens gradually decreased in abundance during the composting process and eventually disappeared during the thermophilic and cooling stage. A bacterium homologous to Bacillus humi first appeared at the early thermophilic stage and was established at the intermediate thermophilic, post-thermophilic, and cooling stages. It was not possible to isolate the B. humi during any of the stages using general culture techniques.

Synthesis of High Purity p-Phenylenediamine from p-Nitroaniline by Catalytic Hydrogenation (Pd/C촉매하 파라니트로아닐린 수소첨가에 의한 고순도 파라페닐렌디아민의 합성공정)

  • Cho, Chul Kun;Chung, Kwang Bo
    • Applied Chemistry for Engineering
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    • v.10 no.8
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    • pp.1210-1215
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    • 1999
  • Optimum conditions of the hydrogenation of PNA to pure PPD were determined in a three-phase slurry reactor with suspended Pd/C catalyst particles. Minimization of mass transfer resistances at the interfaces of both gas-liquid and liquid-catalyst particles and control of overall reaction rate on catalyst surface leaded to decrease the hydrogen starvation on reaction active sites and to reduce the side reactions during hydrogenation. The optimum temperature, pressure, and catalysst concentration were confirmed to be in the range of $60^{\circ}C$, 60~70 psig, and 1~2 g-cat/L, respectively. Reaction rate was zero order with respect to the concentration of PNA and 1st order with respect to the pressure of hydrogen(P). Overall rate expression of the reaction was $R_A=6.44{\times}10^6{\cdot}H{\cdot}P{\cdot}m{\cdot}$exp(-4659/T) where H is constant, m is concentration of catalyst, and T is temperature.

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Effects of Animal Excreta Classification and Nitrogen Fertilizing Level on Productivity of Pasture Plants and Improvement of Soil Fertility in Mixed Grassland (혼파초지에서 가축분뇨의 종류와 시용수준이 목초의 생산성 및 지력증진에 미치는 영향)

  • 육완방;최기춘
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.21 no.4
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    • pp.203-210
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    • 2001
  • To establish the recycling system of animal manure(AM) for environmental preservation and improve the utilization of AM, this study was to investigate the effects of the types and nitrogen application rate of AM on herbage productivity, efficiency of nitrogen utilization, nutritive value and an increase of soil fertility and in mixed grassland. This sudy was arranged in split plot design. Main plots were the types of AM(Cattle feedlot manure, CFM; Pig manure fermented with sawdust, PMFS; cattle sluny, CS) and subplots were the application rate of animal manure, such as 100, 200 and 300kgNiha. I. DM yields of herbage were the highest with CS and decreased by application over ZOOkgNiha AM. 2. Crude protein(CP) ontent was the highest with CFM and followed by CS, and the lowest with PMFS, and increased as application rate of AM increased. 3. Nitrogen(N) yields of CS treatment was higher than that of CFM and CS. and increased significantly as application rate of AM increased(P<0.05). 4. The contents of NDF, ADF and TDN was hardly influenced by the types and application rate of AM. 5. Organic matter(0M) content in the soil was the highest with PMFS and followed by CFM and the lowest with CS. OM content increased significantly as application rate of AM increased(P<0.05). 6. Total nitrogen content of the soil was not affected by the type of AM, but increased significantly as application rate of AM increased(P<0.05). (Key words : Animal manure, Grassland, Cattle feedlot manure, Pig manure fermented with sawdust, Cattle slurry, Soil fertility)

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Development of Preservation Prediction Chart for Long Term Storage of Fermented Cucumber (발효오이의 산패예견표의 개발)

  • Kim, Jae-Ho;Breidt, Fred
    • Journal of Life Science
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    • v.17 no.12
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    • pp.1616-1621
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    • 2007
  • Off-flavors and odors in fermented cucumbers result from the growth of undesirable microorganisms during the secondary fermentation. Under laboratory conditions using a sterile fermented cucumber slurry medium, the spoilage fermentations were reproduced. Using this system the salt and pH conditions that allow the spoilage to occur were determined by varying the NaCl concentration and pH of the slurry medium. At pH 3, no spoilage was observed, regardless of the salt concentration, while at pH 3.5, pH 4, and pH 4.5, spoilage occurred in the 0 and 2% NaCl samples. For pH 5.0 samples, spoilage products were seen for all NaCl treatments. Based on these results the Preservation Prediction Chart was developed. The Chart may be used for selection of proper pH value and salt concentration for long term storage of fermented cucumber.

Effect of Benzalkonium Chloride on Biogas Potential of Pig Slurry (Benzalkonium Chloride가 돈슬러리의 바이오가스 생성에 미치는 영향)

  • Park, H. R.;Choi, H. L.;Suresh, Arumuganainar
    • Journal of the Korea Organic Resources Recycling Association
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    • v.19 no.3
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    • pp.63-72
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    • 2011
  • Benzalkonium chloride is most widely used in S. Korea as a disinfectant in livestock husbandry. Inhibition of biogas potentials were investigated with three different doses of benzalkonium chloride in swine slurry. The system was operated at batch mode. The inhibition rates were 10%, 30~40% and >70% at the dose of 10ppm, 40ppm and 80ppm, respectively assuming it was zero percent in case of no dose. Enzymatic activities were analyzed to determine the enzymatic type which was inhibited by benzalkonium chloride. The acid phosphatase, alkaline phosphatase and protease were shown negatively correlated with biogas potential. Correlation of ${\alpha}$-glucosidase and biogas potentials was observed not high (p<0.01, r=-0.426) while benzalkonium chloride (r=-0.853, p<0.01) and acid phosphatase (p<0.01) with biogas potentials were significantly and negatively correlated. The effect of benzalkonium chloride on Escherichia coli were also evaluated by disc diffusion method. As increase of benzalkonium concentration, inhibition zone of anaerobic bacteria was extended. It revealed that benzalkonium chloride significantly deteriorated biogas potential through inhibition of acetogenic bacteria.