• 제목/요약/키워드: spray-dry

검색결과 183건 처리시간 0.029초

건식세정기에서의 오염물 동시제거를 위한 고온3계평형 모델의 적용과 예비설계에의 응용 (Application of High-temperature 3-phase Equilibrium Distribution to Dry Scrubber for the Simultaneous Removal of $SO_2$ and Vinyl Chloride)

  • 구자공;백경렬
    • 한국대기환경학회지
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    • 제6권1호
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    • pp.85-96
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    • 1990
  • Simultaneous removal efficiencies of hydrophilic and hydrophobic gaseous pollutants are experimentally determined, and the macroscopic removal mechanism of pollutants in a dry scrubber is analyzed using the extended model of three phase equilibrium distribution of pollutant at high temperatures that can describe the different morphological conditions of adsorbent and water at varying relative humidities. For the simplicity, the inside of spray dryer is divided into three regions of ; (1) absorption, (2) three-phase equilibrium, and (3) adsorption, and the removal efficiencies of each pollutants at three regions are observed at different experimental conditions to estimate the effects of important parameters of dry scrubber. The laboratory experiments simulate the three regions of spray dryer with the temperature control and thus evaporation rate of water from the slurry particle. $SO_2$ as a hydrophilic gaseous pollutant and vinyl chloride as a hydrophobic toxic gas are selected for the future field application to soid waste incineration, and the two types of slurry are made of the two sorbents ; 10 wt.% $Ca(OH)_2$, and 10 wt.% NaOH. Result of temperature effect shows the height of absorption plus three-phase region is decreased as the operation temperature is increased, which results in the lower removal efficiency of $SO_2$ but higher removal for vinyl chloride in the adsorption region of dry scrubber. The removal efficiency of $SO_2$ is higher by NaOH slurry than by $Ca(OH)_2$ slurry due to the hygroscopic nature of NaOH, while the removal of vinyl chloride is higher in $Ca(OH)_2$ case. From the analysis of redults using three-phase equilibrium distribution model, the effective two-phase partition coefficients can be obtained, and the possible extention in the application of the three-phase equilibrium model in a dry scrubber design has been demonstrated.

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PVP 결합제를 이용한 지르코니아/알루미나 복합분말의 분무건조 (Spray Drying of Zirconia/Alumina Composite Powder Using PVP as a Binder)

  • 심형보;문주호;김대준
    • 한국세라믹학회지
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    • 제39권5호
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    • pp.446-451
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    • 2002
  • 지르코니아/알루미나 복합분말의 분무건조로 제조된 과립들의 형상과 성형시 과립 경계면 파괴에 분말의 분산 정도, 결합제의 종류, 그리고 고형분말 함량이 미치는 영향을 관찰하였다. 구형의 과립은 복합분말 슬러리가 완전 분산이 되지 않고 약간의 floc을 형성하고 결합제로서 Polyvinyl Pyrrolidone(PVP)을 사용했을 때 얻어졌다. PVP를 결합제로 사용하고 분말함량이 32.5 vol%인 슬러리로 분무건조한 분말은 성형시 과립경계면이 파괴되어 소결밀도는 99.7%이었고 굴곡강도는 850Mpa이었다.

화강풍화토 흙깎기 비탈면 녹화공법 선정 방안 연구 (The Study on the Selection of Revegetation Methods on Weathered Granite Cut-soil Slopes)

  • 김남춘
    • 한국환경복원기술학회지
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    • 제19권2호
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    • pp.121-135
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    • 2016
  • The present study is an analysis of the monitoring results of the four areas that underwent the experimental construction of Straw-net+seedspray, Vegetation media spray method(t=2cm), and Vegetation media spray method(t=3cm), with the purpose of selecting the adequate revegetation of cutting slopes in weathered granite soil. Cutting slopes are mostly designed in the Straw-net+seedspray method, but since weathered granite soil slopes tend to have an infertile soil quality that runs down, it is difficult for seed germination and growth. It is difficult to apply Straw-net+seedspray to weathered granite soil slopes considering the germination rate and coverage rate of the Straw-net+seedspray method, which accompanies erosion and scouring. The final conclusions are summarized as follows. First, Straw-net+seedspray has difficulty recruiting plants to infertile weathered granite soil, which results in a lower coverage rate and fewer species, so it is not adequate construction method. Second, Vegetation spraying methods with wet media are more advantageous in early revegetation. The wet construction methods are faster than the dry construction methods in terms of early germination and its early growth are more excellent. Third, when constructing Vegetation spray methods with dry media, it were more advantageous if the thickness was thicker. When the soil-media is thicker, the soil is resilient to droughts, so the thickness must be flexibly applied according to the soil quality and slant of the weathered granite soil slope. The present study is a monitoring result for some areas of Gangwon-do, so its results may differ from other areas.

Spray Dry한 $\beta$-SiC-Ti $B_2$ 도전성 세라믹 복합체의 특성에 미치는 Annealing 온도 (Effect of Annealing Temperature on the Properties of $\beta$ -SiC-Ti $B_2$ Electrocondutive Ceramic Composites by Spray Dry)

  • 신용덕;주진영;최광수;오상수;서재호
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제52권8호
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    • pp.335-341
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    • 2003
  • The composites were fabricated respectively 61vo1.% $\beta$ -SiC and 39vo1.% Ti $B_2$ spray-dried powders with the liquid forming additives of l2wt% $Al_2$ $O_3$$Y_2$ $O_3$ by pressureless annealing at 1$700^{\circ}C$, 175$0^{\circ}C$, 180$0^{\circ}C$ for 4 hours. The result of phase analysis of composites by XRD revealed $\alpha$ -SiC(6H), Ti $B_2$, and YAG(A $l_{5}$ $Y_3$ $O_{12}$ ) crystal phase. The relative density, the Young's modulus and fracture toughness showed respectively the highest value of 92.97%, 92.88Gpa and 4.4Mpaㆍ $m^{\frac{1}{2}}$ for composites by pressureless annealing temperature 1$700^{\circ}C$ at room temperature. The electrical resistivity showed the lowest value of 8.09${\times}$10$^{-3}$ ㆍcm for composite by pressureless annealing temperature 1$700^{\circ}C$ at $25^{\circ}C$. The electrical resistivity of the SiC-Ti $B_2$ composites was all positive temperature cofficient resistance(PTCR) in the temperature ranges from $25^{\circ}C$ to $700^{\circ}C$.

분무수세한 쌀로 제분한 쌀가루의 저장중 특성 변화 (Properties of Rice Flour Milled from Spray-Washed Rice During Storage)

  • 최소연;이영택
    • 한국식품영양과학회지
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    • 제36권7호
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    • pp.915-920
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    • 2007
  • 쌀을 분무수세한 후 제분하여 제조한 쌀가루를 건식제분 쌀가루와 함께 $5^{\circ}C$, $20^{\circ}C$, $35^{\circ}C$의 저장온도에서 4개월간 저장하면서 저장 중 품질변화를 측정하였다. 저장기간 중에 쌀가루의 수분함량은 감소하는 경향을 보였으며 저장온도가 $5^{\circ}C$에서 $35^{\circ}C$로 높아짐에 따라 수분의 감소 정도가 큰 것으로 나타났다. 분무수세한 쌀가루의 색은 저장 중 L값이 약간 증가하는 경향이었으며 건식제분 쌀가루와 비교할 때 L값이 높아 보다 밝게 나타났다. 분무수세 쌀가루의 RVA 호화양상을 측정한 결과 건식제분 쌀가루에 비해 저장중의 최고점도가 높게 나타났으며, $5^{\circ}C$에서 저장한 쌀가루의 최고점도가 가장 낮은 반면에 $20^{\circ}C$, $35^{\circ}C$로 저장온도가 높아짐에 따라 최고 점도가 증가하였다. 한편 분무수세 쌀가루의 저장중 최종점도는 건식제분 쌀가루에 비해 낮게 나타나 setback 점도는 분무수세한 쌀가루에서 상대적으로 낮았다. 전반적으로 $5^{\circ}C$에서 저장한 쌀가루의 RVA 점도변화가 가장 적은 것으로 나타났다. 쌀가루의 저장 중 총균수는 미미하게 증가하여 저장 4개월에 $10^{3}$정도였으며 분무수세 쌀가루의 총균수가 건식제분 쌀가루에 비해 지속적으로 낮아 분무수세 쌀가루의 미생물의 오염도가 낮은 것으로 분석되었다.

Production of Ready-to-Reconstitute Functional Beverages by Utilizing Whey Protein Hydrolysates and Probiotics

  • Kumar, Sabbini Kalyan;Jayaprakasha, Heddur Manjappa;Paik, Hyun-Dong;Kim, Soo-Ki;Han, Song-Ee;Jeong, A-Ram;Yoon, Yoh-Chang
    • 한국축산식품학회지
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    • 제30권4호
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    • pp.575-581
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    • 2010
  • This investigation was aimed at developing a ready-to-reconstitute beverage by utilizing probiotics and whey protein hydrolysates carrying bioactive peptides. Cheddar cheese whey was ultrafiltered. The 18% protein retentate was subjected to protein hydrolysis using Neutrase. The hydrolyzed retentate was further condensed to 35% total solids and spray-dried at $75^{\circ}C$ outlet air temperature. Different levels of sugar, citric acid and stabilizer were blended for spray-dried hydrolysates. Spray-dried hydrolysate was further inoculated with different levels of probiotics grown in a whey medium and dried in fluidized-bed drier at $40^{\circ}C$ to obtain a ready-to-reconstitute beverage. Hydrolysis was greatest at an enzyme:substrate ratio of 1:25 for 3 h. Spray-dried hydrolysate reconstituted to 1% protein and blended with 15% sugar, 0.2% citric acid and 0.15% xantham gum resulted in a superior product with no sedimentation. Accordingly, sugar, citric acid and xanthum gum were dry-blended with spray-dried hydrolysates. Bifidobacterium bifidum and Lactobacillus acidophilus that was grown separately in a whey medium, blended to produce 2% spray-dried hydrolysate and dried as described above resulted in a readyto-reconstitute beverage mix. The fluidized dried product typically exhibited a probiotic count of $10^8$colony forming units (CFU)/g. However, blending of probiotic to the retentate and direct spray-drying precipitously reduced the probiotic count to $10^4$ CFU/g of powder.

WEAR PROPERTY OF PLASMA-SPRAYED COATING LAYERA IN Cr$_2$O$_3$

  • Pakr, J.M.;Lee, S.W.;Kim, Byong-Kee;Lee, Dong-Won
    • 한국표면공학회지
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    • 제29권6호
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    • pp.745-752
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    • 1996
  • Wear property of plasma spray coating in $Cr_2O_3$ powder manufatured of spray dry method on the aluminum substrate was inspected for the application of piston-ring of automotive enginel. The plama spray coatings were varied with feed rate and particle size. Used the ball-on disc type tribometer, wear volume, friction, surface rougness were investigated. The delamination of the coating layer were observed with SEM. Also the cross-section of wear track were investigated, using optical microscopy. As a result of experiment, wear mechanism was addressed in the various coating process.

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옥외용 고분자 전기절연재료의 염수 및 UV조사에 의한 열화 특성 (The Aging Characteristics of Polymer Electrical Insulation Materials bv UV Radiation and Salt Water Spray)

  • 최남호;한상일;한상옥;박강식;김종석;박양범
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.221-224
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    • 1997
  • In this study we investigated the acting characteristics of Polymers for electrical insulation by UV radiation and salt water spray treatment. We used the Polymers such as EPDM, SR. PTFE. EVA. We measured contact angle and surface resistance to know the aging characteristic of Polymer surface. And we use SEM to observe the change of the surface shape. Dry flashover voltage test impulse voltage test were carried for the polymer insulator(EVA) . Through this experiment and the analysis we could know the polymers have a good resistance to weathering conditions like as salt spray UV irradiation and mix of them. And we can compare the aging characteristics between Polymers. As a result, we could know that the surface characteristics of PTFE is better than the other. And the degree, electrical characteristics is affected by change of surface shape is not big.

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