• 제목/요약/키워드: SALT REDUCTION

검색결과 558건 처리시간 0.027초

후풍의 영향을 배제한 다방향 비래염분 포집기 개발과 비래염분 포집에 관한 연구 (Development of Multidirection Incoming Salt Collector that Excludes Backward Wind)

  • 박동천;안재철;김우재
    • 한국건축시공학회지
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    • 제11권6호
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    • pp.627-633
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    • 2011
  • 철근 콘크리트 구조물의 염해 내구수명 산정을 위해서는 비래염분량 평가가 필수적이다. 현재까지 국내에서도 국외에서 개발된 포집기를 주로 사용해 왔으나 포집기 자체의 결함으로 포집 정확도에 문제가 있다는 지적이 일어왔었다. 본 연구 결과 기존의 포집기는 후풍의 영향을 배제할 수 없어 실제 포집기를 통과하면서 거즈에 부착된 비래염분은 후풍의 영향에 의해 이탈되어 포집량이 낮게 평가됨과 동시에 방향성, 즉 남쪽에서 불어오는 비래염분도 북향하고 있는 포집기에 포집되어 방향에 대한 구분이 없어지는 현상을 해석적, 실험적으로 규명하고, 문제해결형 개량형 포집기를 개발하였다. 또 해안지역에서 실측에 사용하여 높이별 비래염분량 측정과 동시에 포집기의 성능검증을 실시하였다.

마그네슘 제련(製鍊) 기술현황(技術現況)과 리싸이클링 관련(關聯) 대상분야(對象分野) (Current Status of Magnesium Smelting and the Related Recycling Topics)

  • 박형규
    • 자원리싸이클링
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    • 제16권2호
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    • pp.3-11
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    • 2007
  • 최근 국내에서 자동차 부품산업 및 전자기기 산업에서 마그네슘 금속의 수요가 증가하고 있다. 본 고에서는 마그네슘 금속 제련에 관하여 원료 광석, 세계 생산량과 상용화 조업중인 기술들을 요약 정리하였으며, 국내 마그네슘 관련 시장현황과 기술동향들을 조사하였다. 마그네슘 제련은 크게 용융염 제련법과 열환원법 두가지로 대별할 수 있으며 이들 기술의 일반적인 현황을 살펴보았다. 또한, 국내에서 수행중인 마그네슘의 용융염 제련 연구에 대하여 간략히 기술하고, 용융염 제련시 발생되는 염소나 염화수소의 회수 및 처리 등 재활용 분야와 관련기술을 소개하고자 한다.

Recovery of Ammonium Salt from Nitrate-Containing Water by Iron Nanoparticles and Membrane Contactor

  • Hwang, Yu-Hoon;Kim, Do-Gun;Ahn, Yong-Tae;Moon, Chung-Man;Shin, Hang-Sik
    • Environmental Engineering Research
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    • 제17권2호
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    • pp.111-116
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    • 2012
  • This study investigates the complete removal of nitrate and the recovery of valuable ammonium salt by the combination of nanoscale zero-valent iron (NZVI) and a membrane contactor system. The NZVI used for the experiments was prepared by chemical reduction without a stabilizing agent. The main end-product of nitrate reduction by NZVI was ammonia, and the solution pH was stably maintained around 10.5. Effective removal of ammonia was possible with the polytetrafluoroethylene membrane contactor system in all tested conditions. Among the various operation parameters including influent pH, concentration, temperature, and contact time, contact time and solution pH showed significant effects on the ammonia removal mechanism. Also, the osmotic distillation phenomena that deteriorate the mass transfer efficiency could be minimized by pre-heating the influent wastewater. The ammonia removal rate could be maximized by optimizing operation conditions and changing the membrane configuration. The combination of NZVI and the membrane contactor system could be a solution for nitrate removal and the recovery of valuable products.

Chemical Stability of Conductive Ceramic Anodes in LiCl-Li2O Molten Salt for Electrolytic Reduction in Pyroprocessing

  • Kim, Sung-Wook;Kang, Hyun Woo;Jeon, Min Ku;Lee, Sang-Kwon;Choi, Eun-Young;Park, Wooshin;Hong, Sun-Seok;Oh, Seung-Chul;Hur, Jin-Mok
    • Nuclear Engineering and Technology
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    • 제48권4호
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    • pp.997-1001
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    • 2016
  • Conductive ceramics are being developed to replace current Pt anodes in the electrolytic reduction of spent oxide fuels in pyroprocessing. While several conductive ceramics have shown promising electrochemical properties in small-scale experiments, their long-term stabilities have not yet been investigated. In this study, the chemical stability of conductive $La_{0.33}Sr_{0.67}MnO_3$ in $LiCl-Li_2O$ molten salt at $650^{\circ}C$ was investigated to examine its feasibility as an anode material. Dissolution of Sr at the anode surface led to structural collapse, thereby indicating that the lifetime of the $La_{0.33}Sr_{0.67}MnO_3$ anode is limited. The dissolution rate of Sr is likely to be influenced by the local environment around Sr in the perovskite framework.

환원/확산 공정에 의한 고성능 Nd-Fe-B 자성분말의 제조 (Preparation of Highly Efficient Nd-Fe-B Magnetic Powders by Reduction/Diffusion Process)

  • 김동수;진춘강;백연경;최철진
    • 한국분말재료학회지
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    • 제20권3호
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    • pp.197-202
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    • 2013
  • A novel route to prepare Nd-Fe-B magnetic particles by utilizing both spray drying and reduction/diffusion processes was investigated in this study. Precursors were prepared by spray drying method using the aqueous solutions containing Nd salt, Fe salt and boric acid with stoichiometric ratios. Precursor particles could be obtained with various sizes from 2 to $10{\mu}m$ by controlling concentrations of the solutions and the average size of $2{\mu}m$ of precursors were selected for further steps. After heat treatment of precursors in air, Nd and Fe oxides were formed through desalting procedure, followed by reduction processes in Hydrogen ($H_2$) atmosphere and with Calcium (Ca) granules in Argon (Ar) successively. Moreover, diffusion between Nd and Fe occurred during Ca reduction and $Nd_2Fe_{14}B$ particles were formed. With Ca amount added to particles after $H_2$ reduction, intrinsic coercivity was changed from 1 to 10 kOe. In order to remove and leach CaO and residual Ca, de-ionized water and dilute acid were used. Acidic solutions were more effective to eliminate impurities, but Fe and Nd were dissolved out from the particles. Finally, $Nd_2Fe_{14}B$ magnetic particles were synthesized after washing in de-ionized water with a mean size of $2{\mu}m$ and their maximum energy product showed 9.23 MGOe.

염화칼슘 제설제 고농도 처리에 따른 토양개량제와 참억새 식재 처리가 염류저감 및 생육개선에 미치는 영향 (Effects of Soil Amendments and Planting Miscanthus sinensis on Salt Reduction and Growth Improvement in Substrate irrigated with High Concentration of Calcium Chloride Deicing Salts)

  • 주진희;양지;박선영;윤용한
    • 한국환경복원기술학회지
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    • 제22권6호
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    • pp.15-25
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    • 2019
  • Contamination of soil by deicing salt is among the important environment problems due to their toxicity and negative impact to human health and the environment. One of the effective methods for cleaning the soil from deicing salts is desalination using soil amendment-phytoremediation continuum treatment. The purpose of this study was to determine how much of the pH, EC control and Ca2+, Na+, Mg2+, and K+ taken up soil amendments and Miscanthus sinensis, and to evaluate the effect of salt reduction and growth improvement as affected by soil amendment in high concentration of calcium chloride (CaCl2) deicing salts. Results indicated that the addition of soil amendments was decrease the EC and pH, also significantly reduce the leaching of Ca2+, Na+, Mg2+, K+, a chloride ions related deicing salts, compared to the control for CaCl2 10 g/L treatment. It also resulted in an enhanced plant growth and higher plant height, leaf length, leaf width, number of leaves, fresh weight and dry weight in Hydroball treatment + Miscanthus sinensis planting continuum treatment compared to the treatment that planted Miscanthus sinensis only. Therefore, we concluded that soil amendments might be attributed to an accumulation of deicing slats in the roadside soil, resulting in the improvement of Miscanthus sinensis growth.

함산소불소화법을 통한 다공성 폴리에틸렌막의 파울링현상 감소연구 (Studies on the Fouling Reduction through Oxyfluorination of Porous Polyethylene Membranes)

  • 강수연;임지원;정성일
    • 멤브레인
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    • 제24권6호
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    • pp.431-437
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    • 2014
  • 소수성의 폴리에틸렌 다공성막 표면에 오염물질이 흡착됨으로써 발생되는 파울링 현상으로 인한 투과도 감소 문제를 해결하고자 함산소불소화법을 이용하여 막 표면을 친수화 하였다. 함산소불소화 처리 후 접촉각은 $93^{\circ}$에서 $50^{\circ}$까지 감소하였고, 수투과량은 60% 이상 증가하였다. 또한, 모델오염물질 Albumin (form bovine serum, BSA), Humic acid sodium salt (HA), Alginic acid sodium salt (SA) 100 ppm의 수용액을 이용하여 투과도 평가 실험을 수행한 결과 막이 친수화 됨에 따라 오염물질이 흡착되는 정도가 감소하여 투과도가 향상된 것을 확인할 수 있었으며, 특히 SA에 대해서는 파울링 개선효과가 크게 나타나 처리하지 않은 PE막에 비해 투과도가 두 배 이상 향상된 값을 나타내었다.

Electrochemical Behavior of Li-B Alloy Anode - Liquid Cadmium Cathode (LCC) System for Electrodeposition of Nd in LiCl-KCl

  • Kim, Gha-Young;Shin, Jiseon;Kim, Tack-Jin;Shin, Jung-Sik;Paek, Seungwoo
    • 전기화학회지
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    • 제18권3호
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    • pp.102-106
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    • 2015
  • The performance of Li-B alloy as anode for molten salt electrolysis was firstly investigated. The crystalline phase of the prepared Li-B alloy was identified as $Li_7B_6$. The potential profile of Li-B alloy anode was monitored during the electrodeposition of $Nd^{3+}$ onto an LCC (liquid cadmium cathode) in molten LiCl-KCl salt at $500^{\circ}C$. The potential of Li-B alloy was increased from -2.0 V to -1.4 V vs. Ag/AgCl by increasing the applied current from 10 to $50mA{\cdot}cm^{-2}$. It was found that not only the anodic dissolution of Li to $Li^+$ but also the dissolution of the atomic lithium ($Li^0$) into the LiCl-KCl eutectic salt was observed, following the concomitant reduction of $Nd^{3+}$ by the $Li^0$ in Li-B alloy. It was expected that the direct reduction could be restrained by maintaining the anode potential higher that the deposition potential of neodymium.

Recent strategies for improving the quality of meat products

  • Seonmin Lee;Kyung Jo;Seul-Ki-Chan Jeong;Hayeon Jeon;Yun-Sang Choi;Samooel Jung
    • Journal of Animal Science and Technology
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    • 제65권5호
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    • pp.895-911
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    • 2023
  • Processed meat products play a vital role in our daily dietary intake due to their rich protein content and the inherent convenience they offer. However, they often contain synthetic additives and ingredients that may pose health risks when taken excessively. This review explores strategies to improve meat product quality, focusing on three key approaches: substituting synthetic additives, reducing the ingredients potentially harmful when overconsumed like salt and animal fat, and boosting nutritional value. To replace synthetic additives, natural sources like celery and beet powders, as well as atmospheric cold plasma treatment, have been considered. However, for phosphates, the use of organic alternatives is limited due to the low phosphate content in natural substances. Thus, dietary fiber has been used to replicate phosphate functions by enhancing water retention and emulsion stability in meat products. Reducing the excessive salt and animal fat has garnered attention. Plant polysaccharides interact with water, fat, and proteins, improving gel formation and water retention, and enabling the development of low-salt and low-fat products. Replacing saturated fats with vegetable oils is also an option, but it requires techniques like Pickering emulsion or encapsulation to maintain product quality. These strategies aim to reduce or replace synthetic additives and ingredients that can potentially harm health. Dietary fiber offers numerous health benefits, including gut health improvement, calorie reduction, and blood glucose and lipid level regulation. Natural plant extracts not only enhance oxidative stability but also reduce potential carcinogens as antioxidants. Controlling protein and lipid bioavailability is also considered, especially for specific consumer groups like infants, the elderly, and individuals engaged in physical training with dietary management. Future research should explore the full potential of dietary fiber, encompassing synthetic additive substitution, salt and animal fat reduction, and nutritional enhancement. Additionally, optimal sources and dosages of polysaccharides should be determined, considering their distinct properties in interactions with water, proteins, and fats. This holistic approach holds promise for improving meat product quality with minimal processing.