• 상하수도학회지
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• 제19권1호
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• pp.68-77
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• 2005

This study was performed to evaluate the application of corrosion inhibitor and to examine the correlation between corrosion rate and red water in a series of batch tests and a test using auto corrosion monitoring system at A water treatment plant in Gyeonggido. The corrosion study in the auto corrosion monitoring system indicated that Fe concentration decreased by 30~50% and corrosion rate also reduced remarkably with corrosion inhibitor at $1.8mg\;PO_4/L$. After addition of corrosion inhibitor, it was indicated the effective adsorption of the inhibitor on the surface of the pipe line forming a protective film. The corrosion rate increases with the increase in Fe concentration. With $1.8mg\;PO_4/L$ of corrosion inhibitor, the corrosion rate decreased remarkably. Fe concentration had correlation to not only red water problems but also the corrosion rate that actually dissolved into the water, primarily due to the deposition of oxidized iron or other compounds as a scale, which serves as a large reservoir of corrosion by-product. Therefore, corrosion rate can be estimated by Fe concentration. For these reasons, an effective corrosion inhibitor is also an effective red water control reagent. The effect of the corrosion inhibition can last for some time even the application the corrosion inhibitor is discontinued. For the cost effective and efficient corrosion control, the concentration and timing of corrosion inhibitor addition must be determined properly.

• Environmental Engineering Research
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• 제17권1호
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• pp.17-25
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• 2012

Concern about green water problem has surfaced as a serious issue in Korea. In order to solve this problem, it is necessary to research inhibition of green water and corrosion control of copper pipe in water service. This paper discovered that moderate corrosion inhibitors can solve the green water problem and copper corrosion in water service by adding the optimal concentration of corrosion inhibitors based on regulation. Firstly, in the case of phosphate based corrosion inhibitors, as dosage of the corrosion inhibitor increases from 1 mg/L to 5 mg/L, the relative effect of corrosion inhibitor declines rapidly. Secondly, except for 1 mg/L dosage of silicate based inhibitor, relative effects of the inhibitor displays a positive number depending on inhibitor concentration. The most significant result is that the amount of copper release shows a downward trend, whereas the phosphate based inhibitor accelerates copper ion release as the inhibitor dosage increases. Thirdly, as the dosage of mixed inhibitors increases to 10 mg/L, the copper release change shows a similar trend of phosphate based inhibitor. Lastly, according to the Langelier saturation index (LI), silicate based inhibitors have the most non corrosive value. Larson ratio (LR) indicates that phosphate based inhibitors are the least corrosive. Korea water index (KWI) represents that silicate based inhibitors are most effective in controlling copper pipe corrosion.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.710-713
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• 2000

The corrosion protection methods of reinforcing steel in concrete are the various methods such as increasing thickness of cover concrete, using of reinforcing bars coated with epoxy, dosage of corrosion inhibitor as concrete admixture, cathodic protection method and etc. The most economical method of them will be the corrosion protection method using corrosion inhibitor as concrete admixture. Therefore, the purpose of this research is to investigate the performance of corrosion protection of ordinary strength and high strength concrete using corrosion inhibitor, respectively. For this purpose, after manufacturing ordinary strength and high strength concrete with and without corrosion inhibitor, the accelerated corrosion tests for reinforcing steel were conducted according to the periodic cycles (140 day) of wetting ($65^{\circ}C$, 90% R.H.) and drying period ($15^{\circ}C$, 65% R.H.). As a result, th high strength concrete using corrosion inhibitor showed an excellent performance of corrosion protection.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.32-33
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• 2021

The corrosion of the embedded steel rebars and the consequent deterioration of the reinforced concrete structure has become a challenging concern to the construction industries for the fiscal deficit. However, corrosion inhibitors are potential and being widely used for corrosion mitigation to solve such problems. This study has been focused on the mixed type of corrosion inhibitor where one component of the corrosion inhibitor is organic and another one is inorganic material. 0.1 (M) triethanolamine (TEA) and 0.01 (M) sodium hexametaphosphate (SHMP) have been mixed in distilled water to produce the mixed inhibitor. Studies of the steel rebar corrosion in chloride contaminated (3.5 wt.% NaCl) concrete pore (CCCP) solution has been conducted using different concentrations of corrosion inhibitor. Electrochemical impedance spectroscopy (EIS) method is involved to understand the corrosion behaviour of the steel rebars at different exposure durations.

• 상하수도학회지
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• 제26권1호
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• pp.97-106
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• 2012

To investigate the application of corrosion inhibitor on water supply pipes, turbidity, magnitude of corrosion, composition of scale and concentration of metals from an old steel pipe were analysed under inhibitor addition. The concentration of turbidity, iron and copper from the pipes under inhibitor application was 12 ~ 14% of the case which no inhibitor was applied, which suggests the application of inhibitor was very effective for internal corrosion control. In addition, SEM, EDX, XRD and XRF test results showed that application of inhibitor was effective for the decrease of iron concentration and increase of oxygen, phosphorus and calcium concentration, which suggested the existence of protective layer. Therefore, the occurrence of red water will be significantly decreased when inhibitor was applied to the old steel pipes.

• 콘크리트학회논문집
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• 제20권6호
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• pp.741-746
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• 2008

RC 구조물에서 매립된 철근의 부식을 억제하기 위하여 많은 방법들이 소개되어 왔다. 철근의 부식을 억제하는 방법 중 하나가 부식억제제이다. 최근 탄닌산을 이용하여 활성태의 녹을 부동태의 녹으로 전환시킴으로써 부식의 진행을 지연시키는 기술이 개발되었다. 그러나 이 부식억제제가 일반적인 금속 제품에 대한 방식을 위하여 개발되었기 때문에 콘크리트구조물에 대한 성능이 검토되지 않았다. 따라서 본 연구에서는 탄닌산을 이용한 부식억제제의 적용성을 콘크리트 시험체에 대하여 조사하였다. 연구 결과에 따르면, 탄닌산 부식억제제는 콘크리트에 있어 시공성 및 압축강도의 저하를 발생시키지 않았다. 부식억제제가 시멘트 중량당 4% 이상 첨가될 경우, 염화물 침투깊이가 10% 정도 감소하였다. 또한, 탄닌산 부식억제제는 녹을 안정한 상태로 변환시키는 효과를 가지고 있어, 부식 저항성이 향상된다. 특히, 6% 이상의 첨가가 부식 저항성에 효과적인 것으로 나타났다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.221-223
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• 2011

In this study, in order to comprehend performance of corrosion inhibitor, the experiment study was conducted about corrosion characteristic of 3 steps(0.0, norm 1/2, norm) compared to organic corrosion inhibitor standard use of liquid and molar 3 steps(0.0, 0.3, 0.6%) of Chloride by added amount of inorganic corrosion inhibitor by the corrosion inhibitor types about 2.4kg/㎥, 4.8kg/㎥ based on Chloride ion content 1.2kg/㎥ for service life prediction of concrete structure by using Poteniostat.

• 보존과학회지
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• 제34권4호
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• pp.259-271
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• 2018

Outdoor copper alloy is exposed to the atmospheric environment, accelerating corrosion progress compared with indoor copper alloy. In order to prevent corrosion, the outdoor copper alloy is coated with wax to block external corrosion factors. However, corrosion of the inside of the coating film is highly likely to continue without the internal corrosion prevention treatment. B.T.A, which is used as a copper alloy water-soluble corrosion inhibitor, has a high possibility of being harmful to the human body and is mainly used to treat excavated artifacts. This study had selected the water-soluble corrosion inhibitor, which was easier to use than the existing wax and B.T.A being used in corrosion inhibition treatment for outdoor copper alloy. A comparative study was conducted on B.T.A, which is a water-soluble corrosion inhibitor used on excavated artifacts, and $VCI^{(R)}$, $Rus^{(R)}$, and L-cys, an amino acid corrosion inhibitor, used for tin bronze test pieces. The experimental method was conducted for a certain period of time with the salt, acid, and air pollution affecting the corrosion of outdoor copper alloy. Based on experiment results, it was concluded that the best water - soluble copper alloy corrosion inhibitor in the atmospheric environment is $VCI^{(R)}$. and it could be considered to be applied in replacement of B.T.A due to its low harmfulness. In addition, $VCI^{(R)}$ is judged to serve as a corrosion inhibitor for outdoor copper alloy because it showed the best result even in the outdoor exposure test which is a real atmospheric environment.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.112-113
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• 2021

Phosphate based inhibitor is playing a decisive role in inhibiting the corrosion of steel rebar in chloride condition. We have used different amount of ammonium phosphate monobasic (APMB) as corrosion inhibitor in mortar with different amount of chloride ions. The compressive strength, flexural strength, open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization resistance (PPR), scanning electron microscopy (SEM) and Raman spectroscopy were performed to access the effect of inhibitor on corrosion resistance. As the amount of inhibitor is increased, the compressive strength increased. The electrochemical results show that as the amount of inhibitor and chloride ions are increased, the total impedance and corrosion resistance of steel rebar increased attributed to the formation of the stable oxide films onto the steel rebar surface. It is suggested that APMB can work in high concentration of chloride ions present in concrete where phosphate ion helps in formation of stable and protective phosphate based oxide film.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.33-34
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• 2023

Corrosion of reinforcement steel is a major cause of deterioration in reinforced concrete (RC) structures. In order to protect these structures from corrosion, corrosion inhibitors are added to the concrete mix. In recent years, zwitterionic compounds have shown promising results as corrosion inhibitors in concrete due to their ability to form a protective layer on the surface of the reinforcement steel. The experimental study involves preparing concrete samples with different concentrations of adding the hybrid corrosion inhibitor at a high concentration of chloride ions. This study aims to determine the chloride threshold value and service life of hybrid corrosion inhibitors in reinforced concrete based on zwitterions. The samples are subjected to accelerated corrosion tests in a chloride environment to determine the threshold value and service life of the corrosion inhibitor. The effect of hybrid inhibitor on mechanical properties is guaranteed in allowable range. The chloride threshold concentration and service life of hybrid inhibitor containing samples perform greater than those of plain RC.