• Resources Recycling
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• v.15 no.2 s.70
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• pp.58-68
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• 2006

This study is carried out for the purpose of investigating the property of phosphogypsum, and suggesting the proper recycling system for it. The chemical composition, mineralogical composition, particle size distribution and shape of phosphogypsum were investigated. The size distribution and constitution of impurities, distribution of heavy metals are also investigated. In conclusion, the grade and yield of recoverable phosphogypsum were discussed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.146-150
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• 1998

현재 세계적인 토양환경복원의 추세는 단기간의 높은 처리효율을 기대하는 장치위주의 복원기술적용에서 좀 더 처리시간은 걸리나 저비용의 효율적인 처리기술선택으로 옮겨가고 있다. 이는 지금까지 무리한 투자에서 발생한 부작용을 최소화하기 위해서 취해지고 있는 변화로 식물을 이용한 환경복원기술(phytoremediation)은 이러한 변화에 가장 잘 부응하는 발전 가능성이 매우 높은 미래 복원기술 가운데 하나이다. 이에 본 연구에서는 phytoremediation을 이용하여 디젤로 오염된 토양을 복원하고자 하였다. 먼저 대상오염물에 대한 정화능을 나타내는 식물을 선별하기 위해 알팔파, 옥수수, 피, 물피의 오염농도별 생장 률을 살핀 결과 알팔파가 오염농도에 따른 성장저해를 가장 덜 받는 것으로 나타났다. 이에 알팔파의 발아 test를 거친 후 실제상황을 모사하기 위한 column test를 실시하여 디젤의 제거효율을 살펴보았다. 1)외부로부터 pipe line을 따라 공기를 주입하여 산소를 보충한 처리구와 2)알팔파를 심은 처리구, 3)알팔파와 공기를 넣어준 처리구를 설계하여 디젤의 제거과정을 알아본 결과 제거효과가 가장 높은 처리구는 공기와 알팔파를 함께 넣어준 처리구였다. 이를 통해 유류로 오염된 토양에서 산소가 미생물활동에 커다란 제한요인이라는 것과 공정에 공기주입구를 장착함으로써 식물만으로 처리할 때 대두되는 시간적 제약의 문제를 다소 경감시킬 수 있음이 밝혀져 앞으로 이의 활용가능성이 주목된다.

• Resources Recycling
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• v.4 no.3
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• pp.19-25
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• 1995

A Study on the recovery of the valuable metals(Vanadium Molybdenium) was carried out using spent catalysts originated from desulfurizing process of oil refinery. Experiments consisted of pre-roasting for Sulfur and Carbon removal, soda roasting and leaching for the extraction of valuable metals, and selective precipitation of Vanadium and Molybdenium. Effects of temperature and time in roasting for Sulfur removal, of $Na_2CO_3$ concentrations in soda roasting, and of pulp density, temperature and time in leaching were investigated for the recovery of Vanadium and Molybdenium. A optimum condition having over 85% in yield of Vanadium and Molybdenium was found. In the selective precipitation, more than 98% of Vanadium and Molybdenium were obtained by the variation of pH and concentration of additives.

• KSBB Journal
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• v.25 no.2
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• pp.142-154
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• 2010

The protein-bound innerpolysaccharides (IPS) produced by suspended mycelial cultures of Inonotus obliquus have promising potentials as an effective antidiabetic as well as an immunostimulating agents. To enhance IPS production, intensive strain improvement process should be carried out using large amount of UV-mutated protoplasts. During the whole strain-screening process, the stage of solid growth-culture was found to be the most time-requiring step, thus preventing rapid screening of high-yielding producers. In order to reduce the cell growth period in the solid growth-stage, therefore, solid growth-medium was optimized using the statistical methods such as (i) Plackett-Burman and fractional factorial designs (FFD) for selecting positive medium components, and (ii) steepest ascent (SAM) and response surface (RSM) methods for determining optimum concentrations of the selected components. By adopting the medium composition recommended by the SAM experiment, significantly higher growth rate was obtained in the solid growth-cultures, as represented by about 41% larger diameter of the cell growth circle and higher mycelial density. Sequential optimization process performed using the RSM experiments finally recommended the medium composition as follows: glucose 25.61g/L, brown rice 12.53 g/L, soytone peptone 12.53 g/L, $MgSO_4$ 5.53 g/L, and agar 20 g/L. It should be noted that this composition was almost similar to the medium combinations determined by the SAM experiment, demonstrating that the SAM was very helpful in finding out the final optimum concentrations. Through the use of this optimized medium, the period for the solid growth-culture could be successfully reduced to about 8 days from the previous 15~20 days, thus enabling large and mass screening of high producers in a relatively short period.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.228-236
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• 2008

Validation of viral safety is essential in ensuring the safety of mammalian cell culture-derived biopharmaceuticals, because numerous adventitious viruses have been contaminated during the manufacture of the products. Mammalian cells are highly susceptible to Reovirus type 3 (Reo-3), and there are several reports of Reo-3 contamination during the manufacture of biopharmaceuticals. In order to establish the validation system for the Reo-3 safety, a real-time RT-PCR method was developed for quantitative detection of Reo-3 in cell lines, raw materials, manufacturing processes, and final products as well as Reo-3 clearance validation. Specific primers for amplification of Reo-3 RNA was selected, and Reo-3 RNA was quantified by use of SYBR Green I. The sensitivity of the assay was calculated to be $3.2{\times}10^0\;TCID_{50}/ml$. The real-time RT-PCR method was proven to be reproducible and very specific to Reo-3. The established real-time RT-PCR assay was successfully applied to the validation of Chinese hamster ovary (CHO) cell artificially infected with Reo-3. Reo-3 RNA could be quantified in CHO cell as well as culture supernatant. When the real-time RT-PCR assay was applied to the validation of virus removal during a virus filtration process, the result was similar to that of virus infectivity assay. Therefore, it was concluded that this rapid, specific, sensitive, and robust assay could replace infectivity assay for detection and clearance validation of Reo-3.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.216-224
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• 2005

Chromatography has now been used successfully to provide the requisite purity for human plasma-derived biop-harmaceuticals such as coagulation factors and immunoglobulins. Recently, increasing attention has been focused on establishing efficient cleaning procedures to prevent potential contamination by microorganisms as well as carry-over contamination from batch to batch. The purpose of present study was to develop a cleaning validation system for the assurance of virus removal and/or inactivation during chromatography process. In order to establish an assay system for the validation of virus clearance during chromatography cleaning process, a quantitative real-time PCR method for porcine parvovirus(PPV) was developed, since PPV, a model virus for human parvovirus B19, has a high resistance to a range of physico-chemical treatment. Specific primers for amplification of PPV DNA was selected, and PPV DNA was quantified by use of SYBR Green I. The sensitivity of the assay was calculated to be 1.5 $TCID_{50}/ml$. The established real-time PCR assay was successfully applied to the validation of PPV removal and cleaning during SP-Sepharose cation chromatography for thrombin purification and Q-Sepharose anion chromatography for factor VIII purification. The comparative results obtained by real-time PCR assay and infectivity titrations suggested that the real-time PCR assay could be a useful method for chromatography cleaning validation and that it could have an additive effect on the interpretation and evaluation of virus clearance during the virus removal process.

• Resources Recycling
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• v.16 no.3 s.77
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• pp.19-26
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• 2007

The bottom ash of municipal solid waste incineration generated during incineration of municipal solid waste in metropolitan area consists of ceramics, glasses, ferrous materials, combustible materials and food waste and so on. Although the ferrous material was separated by the magnetic separation before the incineration process, of which content accounts for about $3{\sim}11%$ in bottom ash. The formation of a $Fe_3O_4-Fe_2O_3$ double layer(similar to pure Fe) on the iron surface was found during air-annealing in the incinerator at $1000^{\circ}C$. A strong thermal shock, such as that takes place during water-cooling of bottom ash, leads to the breakdown of this oxidation layer, facilitating the degradation of ferrous metals and the formation of corrosion products and it existed as $Fe_2O_3,\;Fe_3O_4\;and\;FeS_2$. So, many problems could occur in the use of bottom ash as an aggregate substitutes in construction field. Therefore, in this study, the separation of ferrous materials from municipal solid waste incineration bottom ash was investigated. In the result, the ferrous product(such as $Fe_2O_3,\;Fe_3O_4,\;FeS_2$ and iron) by magnetic separator at 3800 gauss per total bottom ash(w/w.%) accounted for about 18.7%, and 87.7% of the ferrous product was in the size over 1.18 mm. Also the iron per total bottom ash accounted for about 3.8% and the majority of it was in the size over 1.18 mm.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.1016-1021
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• 2005

We studied on screening and isolation of dominant bacteria in the food waste fermentation process and on effective production of VFAs by isolated bacteria. In the result of study, bacteria of twelve species were isolated by anaerobic medium. Among the 12 isolated species including Escherichia coli, Clostridium formicoaceticum, C. butyricum, C. acetobutyricum. E. coli and Clostridium spp. were occurred dominantly in the fermentation process and regarded as best VFAs producing bacteria. Acetic acid are produced 287 mg/gTS(8,176 mg/L) by E. coli in concentration of $6{\times}10^8\;cells/gTS$, 551 mg/gTS(15,715 mg/L) by Clostridium formicoaceticum in concentration of $5{\times}10^4\;cells/gTS$. Three times as much acetic acid were produced as blank. Butyric acid are produced 214 mg/gTS(6,106 mg/L) by C. butyricum in concentration of $2.5{\times}10^5\;cells/gTS$ and produced 254 mg/gTS(7,261 mg/L) by C. acetobutyricum of concentration of $1.5{\times}10^5\;cells/gTS$. Two times as much butyric acid were produced as blank.

• Journal of the Korean Applied Science and Technology
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• v.35 no.2
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• pp.367-377
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• 2018

Swimming crab(Ovalipes punctatus) is produced in Korea and utilized as semi-processed food at streamed cooked state. Recently, protein hydrolysates have been known as having function such as antioxidant, suppression of hypertension, immunodulatory, alleviation of pain, and antimicrobial activity. This research was investigated to find the functional antioxidant from crab hydrolysates. To fine optimal protease enzyme, alcalase, bromelain, flavourzyme, neutrase, papain, and protamex were selected to evaluate the DPPH radical scavenging activity and finally bromelain to show the best activity was selected. The molecular weight of bromelain hydrolysates were distributed with range from 500 to 3,200 Da and 7 different molecules or more. The amino acids related to antioxidant capacity was about 42.54%. The processes optimization study used was the response surface methodology. The ranges of processes were the reaction temperature of 40 to $60^{\circ}C$, pH 6 to 8, and enzyme concentration 1 to 3%(w/v). As a result, the optimization of process was determined at temperature of $55^{\circ}C$, pH of 6.5, and enzyme concentration of 3%(w/v). In these conditions, degree of hydrolysates were maximum 71.60%. Therefore, we expect that those products are useful as functional food ingredients.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.2
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• pp.97-109
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• 2003

This study was conducted to investigate use possibility on waste water sludges of water disposal plant as raw materials of organic compost at Fertilizer Official Regulation of Fertilizer Management Law in 2002. In heavy metal contents, some water service sludges were discovered a little over than the standard levels of raw material regulated in organic compost and most of them were not reached the levels. But they were difficult for using the raw materials of organic compost owing to shortage of the organic content. It was judged that the fiber and leather sludges were much in the heavy metal contents and they couldn't use as the raw materials of organic compost. There was afraid that a little heavy metal contents of cosmetic sludge were less than the levels, but it was possible to use selectively as a raw material.