• 한국습지학회지
• /
• 제23권1호
• /
• pp.54-59
• /
• 2021

폐수처리장에서 발생하는 바이오가스 중의 황화수소를 처리하기 위하여 습식스크러빙 장치가 적용되었다. 유입 H2S의 농도가 5,000mg/L이상에서 DIWS 장치에 물만을 사용할 경우 25%의 제거율을 나타내어 후속으로 소각처리 공정이 도입되어야만 98% 이상의 제거율을 나타냈다. 유입 H2S의 농도가 5,000mg/L일 때 CH4과 CO2는 각각 8.7%와 28.6% 감소하여 배출되었다. DIWS 장치에 중화약품으로 Na2CO3와 NaOH를 사용하였을 때 pH가 11.2~11.5를 유지하면서 H2S는 97.2% 제거되었다.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.297.1-297.1
• /
• 2003

Organic solvent-based enteric coating technology using hydroxypropyl methylcellulose phthalate (HPMCP) has been developed for many years due to low water solubility of HPMCP. In this work, aqueous HPMCP nanoparticles (HPMCP-NPs) were prepared by neutralization emulsification method using HPMCP powder and ammonium hydroxide (NH40H) in the absence of any organic solvent and emulsifier. (omitted)

• 식품과학과 산업
• /
• 제51권2호
• /
• pp.114-126
• /
• 2018

The production of high quality oil to meet new standard needs a 'next generation' innovative oil refining tool in paradigm shift. 'Nanoneutralization' using controlled hydrodynamic cavitation-assisted Nanoreactor is successfully being introduced and commercialized into edible oil industry and it plays a key driver for sustainable development of food processing. This emerging technology using bubble dynamics as a consequence of Bernoulli's principle by hydrodynamic cavitation in Venturi-designed multi-flow through cell is radically changing the conventionally chemical-oriented neutralization. Nanoneutralization derived by the creation of nanometer-sized bubbles formed through scientifically structured geometric channels under high pressure has been proven to improve mass transfer and reaction rate so substantially reduce the chemicals required for refined vegetable oil and to increase oil yield while even improving oil quality. More researches on science behind this revolutionary technology will help usto better understand the principle and process hence makes its potential applications expandable in extraction, refining and modification of fats and oils processing.

• 한국위험물학회지
• /
• 제2권1호
• /
• pp.31-37
• /
• 2014

Since the unprecedented hydrogen fluoride leak accident in 2012, there has been growing demand for customized technical information for rapid response and chemical accident management agencies including the Ministry of Environment, the National Emergency Management Agency, and the National Police Agency need more information on chemicals and accident management. In this regard, this study aims to provide reliable technical data and guidelines to initial response agencies, similar to accident management technical reports of the US and Canada. In this study, we conducted a questionnaire survey and interviews on initial response agencies like fire stations, police stations, and local governments to identify new information items for appropriate initial response and improvements of current guidelines. We also collected and reviewed the Canada's TIPS, US EPA's hydrogen fluoride documents, domestic and foreign literature on applicability tests of control chemicals, and interview data, and then produced items to be listed in the technical guidelines. In addition, to establish database of on-site technical information, we carried out applicability tests for accident control data including ① emergency shut down devide, safety guard, shut down valve, ground connection, dyke, transfer pipe, scrubber, and sensor; ② literature and field survey on distribution type and transportation/storage characteristics (container identification, valve, ground connection, etc.); ③ classification and identification of storage/transportation facilities and emergency management methodslike leak prevention, chemicals control, and cutoff or bypass of rain drainage; ④ domestic/foreign analysis methods and environmental standards including portable detection methods, test standards, and exposure limits; and ⑤ comparison/evaluation of neutralization efficiency of control chemicals on toxic substances.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제26권1호
• /
• pp.34-44
• /
• 2021

Acid mine drainage (AMD) resulting from pyrite oxidation in mining areas, subsequently leads to soil acidification accompanied by lowering pH and high concentration of metals and metalloids in its surrounding environment. Regarding to this, the microbial amelioration has been considered as a promising option for a more cost-effective and eco-friendlier countermeasure, compared to the use of alkaline chemicals. This study was aimed to evaluate influencing factors in microbially-mediated amelioration of acidic soil spiked by simulated AMD. For this, microcosm experiments were conducted by acid-neutralizing bacterial consortium (dominated by Klebsiella sp. and Raoultella sp.) under the various conditions of AMD spikes (0-2,500 mg SO42-/L), together with acidic mine soil (0-100 g) or sphagnum peat (0-5 g) in the 200 mL of nutrient medium. The employed bacterial consortium, capable of resisting to high level of sulfate concentration (up to 1,500 mg SO42-/L) in low pH, generated the ammonium while concomitantly reduced the sulfate, subsequently contributing to the effective soil stabilization with an evolution of soil pH up to neutral. Furthermore, it demonstrates that suitable condition has to be tuned for successful microbial metabolism to facilitate with neutralization during practical application.

• 펄프종이기술
• /
• 제47권4호
• /
• pp.46-53
• /
• 2015

Paper strengthening system of PVAm (polyvinylamine) has been used with strong negative charge polymer for electrostatic neutralization due to strong positive charge of PVAm. Recently, because of the controversy caused by the possibility of remaining PAM monomers in white water, a search for paper strength agent that can substitute for PAM was suggested. Therefore, this study was carried out to evaluate a dry strength polymer of PVAm. Starch and CMC were used as a substitute for PAM. The dual polymer system of PVAm and anionic charge control agent such as anionic starch or CMC (carboxy methyl cellulose) were found to be very effective as strength agent compared to the chemicals based on acrylamide.

• 기술사
• /
• 제19권4호
• /
• pp.11-21
• /
• 1986

Mine drainage from coal mines is mostly acidic, polluted and/or contaminated, even if its quantity has increased substantially during recent days. This causes two kinds of problems arising at mining districts; one is the environmental disruption and the other is insufficient water supply for living, employee's bathing and industrial purposes. In order to mitigate the aforementioned problems, a specific equipment of Korea type for mine drainage purification has been developed and its prototype manufactured, followed by its applicability tests implemented at mine site. The results of the tests indicates that the new equipment developed is much lower than and economical compared to, other existing neutralization facilities at home and abroad in capital investment at installation stage, the consumption of neutralizing chemicals at operation stage and the requirements of installation site. Whangji area where the prototype water treatment equipment is installed has been sustaining a short supply of usable water, especially in dry seasons and supplementing about 40㎥ of water brought from a location farther than 4km in distance to meet water requirements. The prototype water treatment equipment is however considered capable of providing compressor cooling water in sufficient amount from winter season In the future.

• 한국산림과학회지
• /
• 제3권1호
• /
• pp.43-46
• /
• 1963

본연구(本硏究)의 결과(結果)를 다음과 같이 요약(要約)한다. 1. 중화(中和)시키지 않었는 0.5% Ethyleneimine 수용액(水溶液)에 처리(處理)된 pinus rigida의 종자는 거의 치사(致死)되나 1N HCl로 중화(中和)가 되면 상당(相當)한 발아(發芽)를 보이며, 농도가 2%에 달(達)해도 아직 높은 발아율(發芽率)이 얻어진다. 2. 0.25% 또는 0.50%의 ethyl methansulphonate의 수용액(水溶液)에 Pinus rigida 종자(種子)를 처리(處理)하였을 때에는 초기발아(初期發芽)에 지체(遲滯)가 초래(招來)되나 10일(日) 이후(以后)에 가서는 발아(發芽)가 왕성하게 되었다. 3. 대조구종자(對照區種子)의 germination energy가 얻어졌을 때의 값을 기준으로 해서 분석(分析)하면 표(表) 1에 보인 것과 같은 이곳 mutagenic chemicals와 방사선(放射線)의 비교치사량(比較致死量)이 얻어졌다. 즉 중화(中和)된 1.89%의 ethyleneimine의 수용액(水溶液), 550 rads의 중성자조사량(中性子照射量), 5.7kr의 X선(線) 그리고 6.5kr의 gamma선(線)은 같은 치사효과(致死効果) $LD_{50}$ 를 주었다. 4. 이 시험(試驗)은 이곳 화학약제(化學藥劑)가 특유(特有)한 성질(性質)을 갖인 돌연변이체(突然變異體)의 유기제(誘起劑)이고 또 방사선(放射線)이 그와 같은 목적(目的)으로 사용(使用)되므로 그 효과(効果)를 구명(究明)하고져 수행(遂行)된 것이다.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제11권6호
• /
• pp.489-495
• /
• 2006

In recent years, there has been an interest to use Moringa oleifera as the natural coagulant due to cost, associated health and environmental concerns of synthetic organic polymers and inorganic chemicals. However, it is known that M. oleifera as the natural coagulant is highly biodegradable and has a very short shelf life. This research was carried out to investigate the effects of storage temperature, packaging methods, and freeze-drying on the preservation of M. oleifera seeds powders. Non freeze-dried M. oleifera was prepared into different packaging namely open container, closed container and vacuum packing, whilst, freeze-dried M. oleifera was stored in closed container and vacuum packing. Each of the packaging was stored at room temperature ($30\;to\;32^{\circ}C$) and refrigerator ($4^{\circ}C$). The turbidity removal efficiencies of stored M. oleifera were examined using jar test at monthly interval for 12 months. The results indicated that non freeze-dried M. oleifera kept in the refrigerator ($4^{\circ}C$) would preserve its coagulation efficiency. In addition, closed container and vacuum packing were found to be more appropriate for the preservation of non freeze-dried M. oleifera, compared to open container. Freeze-dried M. oleifera retained its high coagulation efficiency regardless the storage temperature and packaging method for up to 11 months. Besides, higher increment in zeta potential values for water coagulated with freeze-dried M. oleifera indicated the higher frequency of charge neutralization and better coagulation efficiency of freeze-dried M. oleifera, compared to non freeze-dried seeds. As a coagulant, M. oleifera did not affect the pH of the water after treatment.

• 한국환경농학회지
• /
• 제37권1호
• /
• pp.49-56
• /
• 2018

본 연구는 국내에서 다량 취급되고 있는 암모니아 및 톨루엔을 흄 상태로 노출시킨 후 흡수/흡착방법을 달리한 이동형 스크러버를 이용해 각 유해화학물질의 제거효율을 비교 분석하였다. 이동형 스크러버는 기 개발된 장치를 개선하여 와류 세정에 의한 흡수, 유입풍속 조절의 장점을 살리고, 활성탄 및 카본필터를 통한 기체상 유해화학물질의 흡착방법 도입을 통해 단점을 보완하였다. 개선된 장치는 기초성능평가를 통해 적정 제어풍속이 검증되었고, 5% 암모니아수 용액을 흄 상태로 노출시켜 후드 흡입부, 송풍기 배출부 및 세정기가 정상 작동함을 확인하였다. 흡수/흡착방법에 따른 암모니아 제거효율은 90분 경과 후 C${\geq}$PCA>SWA 순으로 가장 우수한 SWA 군의 노출 농도별 제거 효율은 시간이 경과할수록 노출 농도와 무관하게 배출 농도는 증가되었고, 세정액의 pH는 산성에서 염기성으로 변화되었다. 또한, 시간 경과에 따른 노출 농도 별 세정액의 pH 변화와 배출구 농도 변화 사이에 0.9429~0.9491 수준의 정의 상관관계를 나타내었다. 흡착방법에 따른 톨루엔의 제거 효율은 초기 10분 경과 후 배출구농도에서 C>CMA${\geq}$GCA 순을 나타내다 90분 경과까지 일정한 농도로 유지되었다. 가장 우수한 GCA 군의 노출 농도별 제거 효율은 초기 10분 경과 시 노출 농도에 비례하여 배출 농도가 높은 경향이었다. 이와 같은 결과를 통해 개선된 이동형 스크러버는 중화반응에 의해 산성 또는 염기성 유해 화학물질의 제거 뿐 아니라, 활성탄 등의 흡착기능 개선을 통해 VOCs 제거에도 효과적이었다. 하지만, 실제 현장에서 활용이 가능하도록 세정액 pH를 지속적으로 유지하여 연속적으로 흡수 제거할 수 있는 방법과 노출되는 화학물질 농도와 흡착제의 관계에서 파괴점, 포화점, 흡착속도 등의 물리적인 요소가 추가적인 연구를 통해 도출되어야 할 것이다.