• Journal of Environmental Science International
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• v.9 no.5
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• pp.409-414
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• 2000

In order to examine the availability and effectiveness of crab shell for the removal of heavy metals in aqueous solution the crab shell was compared with cation exchange resin(CER), zeolite granular activated carbon (GAC) and powdered activated carbon(PAC) on aspects of heavy metal removal capacity rate and efficiency. In the removal of Pb, Cd and Cr, the heavy metal removal capacity of crab shell was higher than those of any other sorbents (CER, zeolite, GAC, PAC) and the order of heavy metal removal capacity was crab shell>CER>zeolite>PAC GAC. However in the removal of Cu, the result of crab shell was slightly lower than that of CER. The initial heavy metal removal rate was affected by the sorts of sorbents and metals. In all heavy metals the heavy metal removal rate of crab shell was higher than those of any other sorbents. Under the heavy metal concentration of 1.0 mmole/$\ell$ the heavy metal removal efficiency of crab shell was maintained as 93~100% which was much higher than those of any other sorbents.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.661-666
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• 1998

Liquid phase adsorption equilibria of amines in an aqueous solution onto high silica zeolite pellets (HSZ), macroreticular resin particles (MR) and granular activated carbon (GAC) were determined using a batch bottle technique at 298K. The isotherm curves of HSZ-amines and GAC-amines indicate the nonlinear relationship of unfavorable adsorption type of HSZ-amines and favourable one of GAC-amines. However the curves of MR-amines represent the linear pattern of an adsorption isotherm. Among various equilibrium isotherms, the three parameters of the Redlich-Peterson equation and the two parameters of the Freundlich equation are found to be the most satisfactory within the range of this study. The two parameters of the Langmuir isotherm were not applicable to the present adsorption systems. The amines were adsorbed on the HSZ, MR and GAC in the following sequence of adsorptivity; aromatic amines > primary amines > secondary amines. The product of the Freundlich constants, k and n, proportionally increased with the boiling point, molar volume and dissociation constants of amines adsorbed on HSZ, MR and GAC.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.134-139
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• 2000

Crab shell의 중금속 제거 가능성과 그 효율을 검토하기 위하여 chemical sorbent인 cation exchange resin(CER), zeolite, granular activated carbon(GAC), powdered activated carbon(PAC)의 중금속 제거능을 비교한 결과 다음과 같은 결론을 도출할 수 있었다. 1) 0.1 mM～l.0 mM의 초기 중금속 농도에서 중금속 제거량에 미치는 영향을 비교해 보았을 때 중금속 제거의 평형에 도달하는 시간은 농도가 높을수록 오래 걸렸으며 단위 흡착제 질량당 중금속 제거량은 초기 중금속 농도가 높을수록 증가하였다. 특히 구리 이온 제거 실험에서는 낮은 농도에서 crab shell의 구리 이온 제거량이 CER의 경우보다 조금 떨어지는 경향을 보였으나, 대부분의 중금속 제거에 있어서는 crab shell이 다른 chemical sorbent에 비해 뛰어난 중금속 제거능력을 보였다. 2) 흡착 등온 모델에 적용해 보았을 때, 단위 흡착제 질량당 중금속 최대 흡착량이 crab shell > CER > zeolite > PAC =GAC의 순으로, 모든 중금속 제거 실험에서 crab shell이 가장 뛰어난 것으로 나타났다. 실제 폐수처리 공정에서는 GAC나 PAC가 많이 이용되고 있는데, 수중의 중금속을 보다 효율적이고 경제적으로 처리할 수 있는 crab shell을 폐수처리 공정에 응용할 수 있는 방안을 검토할 필요성이 있을 것으로 판단된다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.281-288
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• 2002

Crab shell 충진 칼럼을 이용한 수중 중금속의 연속적 제거에 있어서 다른 흡착제 (CER, GAC, Zeolite)와 비교 실험을 통하여 crab shell의 중금속 제거능을 알아보았다. 수중 $Pb^2+/{2+}$ 의 column을 이용한 연속적제거에 있어서 미세침전부분이 외부로 배출됨으로 칼럼 외부에 여과시스템의 도입함으로써 중금속 제거능을 높일 수 있을 것으로 판단된다. 중금속의 연속적 제거에 있어서 CER의 1,000 BVs까지의 전체 제거량은 0.35mmol/g, GAC는 0.17mmo1/g, zeolite는 0.16 mmol/g으로 나타났고 crab shell에 의한 중금속 제거량은 0.61 mmol/g으로 다른 흡착제보다 높은 제거효율을 보였다. 수중 중금속의 연속적 제거에 있어서 여러 흡착제의 제거 순서는 crab shell > CER > GAC > zeolite 로 나타났다. Crab shell의 경우는 파과점이 2,000 BVs에서 나타나므로 일반적인 폐수처리의 화학적 처리 후 잔존하는 저농도의 중금속을 제거를 위해 crab shell 충진 칼럼이 유용 할 것으로 판단된다. Crab shell의 재사용 가능성을 알아보기 위하여 crab shell을 이용한 중금속 제거공정에서 연속적인 중금속제거와 탈착과정을 통하여 보았을 때 1회에서 $Pb^2+/{2+}$제거된 량은 0.71 mmol/g 제거되었고 2회에서는 0.27 mmol/g, 3회에서는 0.02 mmol/g으로 급격하게 crab shell의 제거능이 떨어지는 것을 관찰 할 수 있다. 이는 crab shell이 재사용이 불가능 할 것으로 판단되나 다른 흡착제보다 월등한 제거효율을 보이므로 수중 중금속의 연속적 제거 흡착제 적합할 것으로 판단된다.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.5
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• pp.709-717
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• 2006

This research was conducted to figure out the feasibility of several sorption materials to treat various pollutants in road runoff. In advance of the major feasibility test with various sorption materials, the separation process with $1.2{\mu}m$ filter was conducted and showed that slight portion of pollutants was removed(Orgamic pollutant - 20%, Nutrient salt - 50%, Heavy metals - 0~30%). To remove dissolved pollutants in runoff, various materials were tested through an isotherm sorption experiment. As a result, GAC showed most effective material among them to lessen most contaminants such as organic compounds and nutrients. On the other hand, ion-exchange resin and Zeolite showed limited usefulness on the some heavy metals. Freundlich model was most suitable for the current experiment data, and the amount of adsorbent (GAC) could calculated based on this model.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.234-240
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• 2010

The effectiveness of adding powdered zeolite and granular activated carbon (GAC) before starvation into biological reactor for recovering its performances was investigated. Two types of carrier addition in Sequencing Batch Reactor (SBR) system for non-saline and saline wastewater were evaluated after starvation periods. During the experiment, settleablity (SVI), floc size, fractal dimension, $COD_{Mn}$, T-N, T-P removal efficiencies and recovery time were monitored. When the wastewater feeding was resumed after starvation period for 5days, the SVI increased at the beginning of resumption and then decreased with time in both types. And the larger the floc size and fractal dimension of floc, the more increased removal efficiency for $COD_{Mn}$, T-N and T-P was also. Its performance recovery was strongly correlated with floc size and fractal dimension of activated sludge. After resuming the wastewater feeding, the SVI, floc size, fractal dimension, $COD_{Mn}$, T-N, T-P removal efficiency of SBR with carrier improved and reached its initial value faster compared to those of SBR without carrier.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.6
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• pp.697-704
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• 2008

Stormwater runoff from urban road area as non-point source has a tendency of including lots of pollutants at initial rain period. Recently, there are several cases of having installed treatment facilities for reducing pollution discharge from the impervious cover in urban area to prevent watershed environment from getting worse. The filtration type among non-point source treatment systems has been known as one of the most efficient system for treatment of non-point source pollutants. Therefore, various kinds of filter media such as expanded polypropylene(EPP), granular activated carbon, zeolite, perlite, illite, sand, gravel has been developed. This study was conducted to verify performance and hydraulic characteristics of filter media as measures for non-point source. The experiment was carried out to evaluate applicability and variation of 4 kind of most popular filter media(EPP, GAC, Zeolite, Perlite) in headloss with elapsed time and influent flow rate and to obtain data base that could be used to establish management plan for road runoff treatment. In experiment by tap water, it showed that EPP and perlite those are floatable materials showed stable operating performance and lower headloss than the others.

• Journal of Korean Society on Water Environment
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• v.27 no.2
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• pp.167-177
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• 2011

Billions of barrels of briny produced water are generated in the United States every year during oil and gas production. The first step toward recovering or reusing this water is to remove the hazardous organics dissolved in the briny produced water. Biological degradation of hazardous volatile compound could be possible regardless of salinity if they were extracted from briny water. In the current work, the effectiveness of a vapor phase biofilter to degrade the gas-phase contaminants (benzene, toluene, ethylbenzene and xylenes, BTEX) extracted from briny produced water was evaluated. The performance of biofilter system responded well to short periods when the BTEX feed to the biofilter was discontinued. To challenge the system further, the biofilter was subjected to periodic spikes in inlet BTEX concentration as would be expected when it is coupled to a Surfactant-Modified Zeolite (SMZ) bed. Results of these experiments indicate that although the BTEX removal efficiency declined under these conditions, it stabilized at 75% overall removal even when the biofilter was provided with BTEX-contaminated air only 8 hours out of every 24 hours. Benzene removal was found to be the most sensitive to time varying loading conditions. A passive, granular activated carbon bed was effective at attenuating and normalizing the peak BTEX loadings during SMZ regeneration over a range of VOC loads. Field testing of a SMZ bed coupled with an activated carbon buffering/biofilter column verified that this system could be used to remove and ultimately biodegrade the dissolved BTEX constituents in briny produced water.

• Journal of Environmental Science International
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• v.11 no.3
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• pp.241-246
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• 2002

One of the Musty and earthy smell compounds in raw water is generally attributed to 2-methylisoborneol (2-MIB). It is well known that activated carbon and oxidants such as $O_3$, Cl $O_2$, are effective ways to control 2-MIB. In isotherm equilibrium experiments, 2-MIB in distilled water was much more adsorbed to the activated carbon(A/C) than raw water containing dissolved organic carbon (DOC). The Freundlich constants(k) of distilled water and raw water were 3.36 and 0.049, and 1/n values were 0.80 and 0.42, respectively. The 2-MIB residual rate were Y = $e^{-0}$.55x/~ $e^{-0}$.54x/ with Ozone( $O_3$) dose by 5 minutes contact time at the 241 and 353 ng/L initial concentrations. The 2-MIB residual rate were Y = $e^{-0}$.32x/~ $e^{-0}$.35x/ with Chlorine dioxide(Cl $O_2$) dose by 15 minutes contact time at the 89 and 249 ng/L initial concentrations. 2-MIB was decreased from 1911 ng/L to 569ng/L by post-ozonation(70%removal efficiency) and removal efficiencies of 2-MIB by the following 4 kinds Granular Activated Carbon(GAC) process such as coal base, coconut base, wood base and zeolite＋carbon base were 95.8, 89.5, 88.4, and 93.7% respectively.ely.