• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.261-266
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• 1997

가장 넓게 쓰이고 있는 알칼리염소법에 의한 도금폐수 처리법은 약 50년전에 Dodge와 Zabban에 의해 발표된 이론에 기초하고, 이것은 pH 및 ORP에 의존하는 반응으로 차아염소산이 시안화물을 시안산염으로 산화시키는 것이며, 알칼리조건하에서 염소화를 하는 동안에 시안화물이 파괴되고 중금속염은 침전을 생성한다. 이 반응은 1단계에서 시안산기가 바로 시안산나트륨으로 되는 것이 아니고 반응의 중간생성물인 염화시아노겐(CNCI)이라고 하는 독성물질이 생성되기 때문에 안전상의 문제가 있다. 또 알카리 염소법은 고농도일 경우에는 처리가 대단히 어렵고, 저농도일지라도 철, 니켈 및 구리와 같이 중금속성분이 다량 혼입되면 배출허용기준치이하로 처리하기는 사실상 불가능하다. (중략)

• Journal of the Korea Institute of Building Construction
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• v.23 no.4
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• pp.349-358
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• 2023

This research aimed to enhance the initial strength of concrete that is mixed with ground granulated blast furnace slag, as well as to fortify its resistance to carbonation and chloride ion permeation. To achieve this, alkaline aqueous, produced through the electrolysis of potassium carbonate, was employed as the mixing water in the preparation of concrete. To substantiate the increment in initial strength, compressive strength measurements of the concrete were executed. Additionally, an accelerated carbonation test and a chloride ion permeation resistance test were undertaken. The results confirmed that the initial strength of the concrete, which utilized electrolysis alkaline aqueous as mixing water, exhibited an improvement in comparison to concrete mixed with conventional water. It was also verified that both carbonation resistance and chloride ion permeation resistance showed enhancements.

• Journal of the Korea Institute of Building Construction
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• v.16 no.4
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• pp.321-329
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• 2016

The use of ternary blended cement consisting of Portland cement, granulated blast-furnace slag (GGBFS) and fly ash has been on the rise to improve marine concrete structure's resistance to chloride attack. Therefore, this study attempted to investigate changes in chloride attack resistibility of concrete through NT Build 492-based chloride migration experiments and test of concrete's ability to resist chloride ion penetration under ASTM C 1202(KS F 2271) when 1.5-2.0% of alkali-sulfate activator (modified alkali sulfate type) was added to the ternary blended cement mixtures (40% ordinary Portland cement + 40% GGBFS + 20% fly ash). Then, the results found the followings: Even though the slump for the plain concrete slightly declined depending on the use of the alkali-sulfate activator, compressive strength from day 2 to day 7 improved by 17-42%. In addition, the coefficient from non-steady-state migration experiments for the plain concrete measured at day 28 decreased by 36-56% depending on the use of alkali-sulfate. Furthermore, total charge passed according to the test for electrical indication of concrete's ability to resist chloride ion penetration decreased by 33-62% at day 7 and by 31-48% at day 28. As confirmed in previous studies, reactivity in the GGBFS and fly ash improved because of alkali activation. As a result, concrete strength increased due to reduced total porosity.

• Environmental engineer
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• s.179
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• pp.72-76
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• 2001

본 연구의 목적은 기존 혼합도금폐수 처리공정의 문제점(현재 도금폐수처리시 사용되고 있는 알칼리 염소법은 작업장내의 기기 부식, 작업환경 열악, 배출수 내의 활성염소 잔류 및 폐수처리 공정의 적정화 미흡)을 해결하고 폐수처리 공정에서 유해 물질을 즉시 분석할 수 있는 정량제를 국산화하여 국내의 도금폐수 처리공장에 보급하는 것이다. 개발한 기술은 기존 도금폐수 처리공정에서 사용하고 있는 과다한 차아염소산소다 사용법을 대체한 기술로 처리공정의 적용법이 간단하

• Journal of Korean Society of Environmental Engineers
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• v.30 no.5
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• pp.524-533
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• 2008

Industrial wastewater generated in the electroplating and metal finishing industries typically contain toxic free and complex metal cyanide with various heavy metals. Alkaline chlorination, the normal treatment method destroys only free cyanide, not complex metal cyanide. A novel treatment method has been developed which destroys both free and complex metal cyanide as compared with Practical Plant(I). Prior to the removal of complex metal cyanide by Fe/Zn coprecipitation and removal of others(Cu, Ni), Chromium is reduced from the hexavalent to the trivalent form by Sodium bisulfite(NaHSO$_3$), followed by alkaline-chlorination for the cyanide destruction. The maximum removal efficiency of chromium by reduction was found to be 99.92% under pH 2.0, ORP 250 mV for 0.5 hours. The removal efficiency of complex metal cyanide was max. 98.24%(residual CN: 4.50 mg/L) in pH 9.5, 240 rpm with 3.0 $\times$ 10$^{-4}$ mol of FeSO$_4$/ZnCl$_2$ for 0.5 hours. The removal efficiency of Cu, Ni using both hydroxide and sulfide precipitation was found to be max. 99.9% as Cu in 3.0 mol of Na$_2$S and 93.86% as Ni in 4.0 mol of Na$_2$S under pH 9.0$\sim$10.0, 240 rpm for 0.5 hours. The concentration of residual CN by alkaline-chlorination was 0.21 mg/L(removal efficiencies: 95.33%) under the following conditions; 1st Oxidation : pH 10.0, ORP 350 mV, reaction time 0.5 hours, 2nd Oxidation : pH 8.0, ORP 650 mV, reaction time 0.5 hours. It is important to note that the removal of free and complex metal cyanide from the electroplating wastewater should be employed by chromium reduction, Fe/Zn coprecipitation and, sulfide precipitation, followed by alkaline-chlorination for the Korean permissible limit of wastewater discharge, where the better results could be found as compared to the preceding paper as indicated in practical treatment(I).

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1996.12a
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• pp.75-75
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• 1996

최근 가장 관심이 집중되고 있는 음용수중의 미량오염물질로는 인위적으로 첨가되는 소독제(disi octant)로 인한 소독부산물(disinfection by-products: DBPs)을 들 수 있다. 1970년대부터 염소소독시 수중의 유기오염물길과 반응하여 발암성물질 과 돌연변이 물질이 다수 함유되어 있는 클로로포름(chloform)을 포함한 트리할로메탄(Trih리omethane: THMs)의 생성이 발견되었으며 이로 인한 건강상의 영향이 지속적으로 보고되고 있다. 염소소독시 780가지 이상의 화합물이 염소와 휴믹산(humic acids)과의 반응에 의해 생성되며, 이중 대부분이 할로겐 화합물로 알려져 있다. 염소 소독부산물로는 인체발암력을 지니고 있는 트리할로메탄(THMs) 이외에도 할로아세틱산(Haloaceticacids: HAAs), 할로아세토나이트릴(Haloacetbnitriles: HANs)등이 주 생성물질인 것으로 알려져 있으나 우러나라의 원수특성에 따른 소독부산물의 생성능 (Formation potential)에 대한 연구가 미흡한 실정이다. 본 연구에서는 우리나라 주요 4대강(한강, 대청호, 영산강, 낙동강)의 원수를 실험실내에서 염소처리하여 생성되는 소독부산물의 생성농과 pH, 체류시간 등의 조건에 따라 생성능을 조사하였다. 각 화합물은 추출 및 농축과정을 거친 후 GC/MSD를 사용하여 물질을 확인한 후 할로겐화합물에 민감한 GC/ECD를 사용하여 시료를 분석하였다. pH와 시간, 원수중의 유기물 함량이 소독부산물의 생성에 많은 영향을 미치는 것으로 나타났다. THMs은 알칼리에서, HAAs의 경우는 약산성에서 접촉시간이 증가할수록 높은 생성능을 보였고, HANs의 경우는 급속히 생성했다가 시간이 경과함에 따라 소멸하며 약산성에서 높은 생성능을 보임을 알 수 있었다, 강별로는 낙동강에서 THMs파 HANs의 생성능이 비교적 높았고, 영산강에서는 HAAs의 생성능이 높았다. 각 원수의 특성에 따른 생성능을 파악함으로써 생성능 저감방안을 마련하며, 소독 부산물질의 인체노출평가에 따른 위해성평가를 통해 관리기준을 설정해야 할 것이다.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.269-274
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• 2013

We are used with the alkaline ion water which an application field does to object for drinking water compare with the alkaline ion water which asked ion acid electrolysis so as to be very different. This is used with sterilization disinfection use by residual chlorine in case of strong acidity according to ph intensity, and in case of middle acidity use by washing and face washing, and mix with meal materials in case of weak acidity widely usable in cooking. Acid ion water generates as we electrolyze water. Chlorine gas and sodium hydroxide etc. was generated at electrolysis process, and we have toward sterilizing power. Derelicts such as chlorine, phosphorus, sulfur etc. are gathered from a negative ion, and we make acid ion water to + electrode direction in electrolysis. We used a diaphragm in order to disconnect too acid water and alkaline water. We implemented so that the acid water which it came down to three kinds of PWM voltage to PWM (pulse width modulation) control, and implementation method of ph intensity change authorized ph intensity between weak acidity to electrode in strong acidity as we used Microprocessor, and intensity was adjusted successively by PWM control was generated.

• Membrane Journal
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• v.30 no.4
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• pp.276-281
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• 2020

A research was conducted on the removal of ion from the solution involving the alkali metal ion and chlorine ion using ion exchange resin. The cation exchange resin and anion exchange resin was used for the remove of metal ion (Na⁺ and K⁺) and chlorine ion (Cl^-), respectively. In the case of solution A (involving 36,633 ppm of Na⁺ and 57,921 ppm of Cl^-), the Na⁺ ion and Cl^- ion were removed over 99% within 20 min. In the case of solution B (involving 1,638 ppm of K⁺), the K⁺ ion was removed over 99% within 3 min.

• Journal of Conservation Science
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• v.26 no.4
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• pp.397-406
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• 2010

The most ideal method to measure the water-soluble $Cl^-$ ion eluted from iron artifacts is conducting the analysis on desalting solution by Ion Chromatography. But most institutes related to cultural heritages use Cl meter by reason of lack of budget and experts. This study evaluated reliability and stability between Cl meter and Ion Chromatography by doing cross-validation with results from two methods to detect $Cl^-$ ion of desalting solution. From D.I water, extremely small quantities of $Cl^-$ ion was detected by the influence of remaining water-soluble $Cl^-$ ion at the electrode of Cl meter and water-soluble $Cl^-$ which remains in Sodium sesquicarbonate, components of reagent was detected as well. The first desalting solution had the most $Cl^-$ ions, $Cl^-$ ion slightly decreased from the second to the fourth desalting solution and tend to decrease again at the stage of dealkalified in D.I water. Each Cl meter has the standard deviation according to the measured numbers and the higher concentration of $Cl^-$ ion the desalting solution has, the wider the deviation is. But when the concentration of $Cl^-$ ion is low, it was stable to use Cl meter to detect the concentration of $Cl^-$ ion from iron artifacts because there is the small deviation, It is thought that conductivity meter method is not suitable for measuring $Cl^-$ ion, because the electrical conductivity of alkaline solution is too high to measure $Cl^-$ ion.

• Clean Technology
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• v.27 no.2
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• pp.168-173
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• 2021

The treatment of plated wastewater is subject to various and complex processes depending on the pH, heavy metal, and cyanide content of the wastewater. Alkali chlorine treatment using NaOCl is commonly used for cyanide treatment. However, if ammonia and cyanide are present simultaneously, NaOCl is consumed excessively to treat ammonia. To solve this problem, this study investigated 1) the consumption of NaOCl according to ammonia concentration in the alkaline chlorine method and 2) whether ferrate (VI) could selectively treat the cyanide. Experiments using simulated wastewater showed that the higher the ammonia concentration, the lower the cyanide removal rate, and the linear increase in NaOCl consumption according to the ammonia concentration. Removal of cyanide using ferrate (VI) confirmed the removal of cyanide regardless of ammonia concentration. Moreover, the removal rate of ammonia was low, so it was confirmed that the ferrate (VI) selectively eliminated the cyanide. The cyanide removal efficiency of ferrate (VI) was higher with lower pH and showed more than 99% regardless of the ferrate (VI) injection amount. The actual application to plated wastewater showed a high removal ratio of over 99% when the input mole ratio of ferrate (VI) and cyanide was 1:1, consistent with the molarity of the stoichiometry reaction method, which selectively removes cyanide from actual wastewater containing ammonia and other pollutants like the result of simulated wastewater.