• 대한환경공학회지
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• 제22권5호
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• pp.837-847
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• 2000

고농도의 유기물과 질소성분을 포함하는 맥주공장과 석유화학 산업폐수를 처리하기 위하여 실험실 규모의 혐기/호기 순산소-생물막 공정 (POB)이 이용되었다. 그리고 A/O POB process와 장기폭기법의 경제성분석도 수행되었다. TOC 농도기준으로 70에서 150 mg TOC/L 범위의 맥주공장폐수가 유입되었을 때 TOC 제거율은 각각 92% 이상으로 좋은 효율을 보였다. 석유화학폐수의 경우 초기 TOC제거율은 52%로 매우 낮았지만 32일 이후에는 86%의 TOC 제거율을 나타내었으며, TKN의 제거율은 유입부하가 증가함에도 불구하고 27일 이후에 71%의 제거율로 유지되었다. 순산소 생물막공법은 초기 건설비인 순산소 발생장치 (PSA)와 메디아 설치비가 소요되기 때문에 장기폭기법에 비하여 약 2.9배 정도 높았다. 이에 반해서 순산소 생물막공법은 극히 적은 잉여슬러지 발생량과 슬러지의 재순환의 불필요, 낮은 에너지 소요량 등의 많은 장점들로 인하여 운전비와 유지비가 약 2.5배 정도 장기폭기법 보다 적었다. 그러므로 장기적인 측면에서 보면 순산소 생물막공법이 높은 처리효율을 가지면서도 장기폭기법보다 경제적인 것으로 생각된다.

• Journal of Information Processing Systems
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• 제17권2호
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• pp.242-252
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• 2021

Following the intuition that the local information in time instances is hardly incorporated into the posterior sequence in long short-term memory (LSTM), this paper proposes an attention augmented mechanism for fault diagnosis of the complex chemical process data. Unlike conventional fault diagnosis and classification methods, an attention mechanism layer architecture is introduced to detect and focus on local temporal information. The augmented deep network results preserve each local instance's importance and contribution and allow the interpretable feature representation and classification simultaneously. The comprehensive comparative analyses demonstrate that the developed model has a high-quality fault classification rate of 95.49%, on average. The results are comparable to those obtained using various other techniques for the Tennessee Eastman benchmark process.

• 한국환경보건학회지
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• 제20권3호
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• pp.1-12
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• 1994

Wastewaters being treated and final effluents were collected from 3 wastewater treatment plants of petrochemical industries, from August 31 to October 4, 1993 in an interval of 10 days, and further analysed by GC/FID to investigate discharge situation and removal efficiency on polycyclic aromatic hydrocarbons. The results were as follows: 1. The PAHs 294.57 $\mu$g/l were discharged in primary treatment effluent of plant A to manufacture vinyl acetate resin and acryl, and removed 54.51% by aeration and totally 84.71%. 2. The PAHs of the highest concentration were discharged in primary treatment effluent of plant B to manufacture PS resin and ABS resin, but removed 91.65% by activated sludge process and 98.19% by activated carbon to discharge PAHs of the lowest concentration comparing to another treatment operations. 3. The PAHs 99.96 $\mu$g/l of the lowest concentration were discharged in wastewater of plant C to manufacture epoxy resin, and removed 80.48% by activated sludge process. 4. B treatment system including activated carbon showed up the best removal efficiency of PAHs. Activated carbon therefore, seems to be effective as tertiary treatment. 5. Correlation coefficient of components to total PAHs was generally low, and correlation coefficients of phenanthrene, pyrene and acenaphthylene to total PAHs were each 0.98, 0.97 and 0.80, respectively. Correlation coefficient of the sum of phenanthrene, pyrene and acenaphthylene to total PAHs was 0.99, so that the sum of phenanthrene, pyrene and acenaphthylene was available as index to estimated total PAHs. 6. Phenanthrene and Chrysene were very well treated biologically and acenaphthylene and fluoranthene were untreated biologically. 7. Considering EPA standards, it seems that the concentration of phenanthrene, pyrene, fluoranthene, and benzo(k)fluoranthene is high level.

• 한국가스학회지
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• 제13권4호
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• pp.53-60
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• 2009

냉각수, 수증기 등과 같은 유틸리티를 사용하는 설비에서는 장치손상지역에 의한 사고 피해크기(COF)가 0의 값을 나타내고, 이로 인해 위험도가 0으로 나타난다. 따라서 본 연구에서는 위험기반검사(RBI)에서 장치손상지역에 의한 COF로부터 위험도를 산출하는 방법을 개선하여 재정적 손실에 의한 COF로부터 위험도를 산출하는 RBI 절차를 개발하였다. 그리고 장치손상지역과 재정적 손실에 의한 위험도로부터 검사주기를 동시에 산정하는 RBI 프로그램(KS-RBI Ver 3.1)을 개발하여 석유화학공정에 적용하였다. 그 결과, 재정적 손실에 의한 COF로부터 산출한 위험도는 장치손상지역에 의한 COF로부터 산출한 위험도 결과와 거의 유사하였다. 그러나 유틸리티를 사용하거나 고가의 설비에서는 장치손상지역에 의한 경우보다 재정적 손실에 의한 COF로부터 설비의 위험도를 보다 정확하게 산출할 수 있었다.

• 한국멀티미디어학회논문지
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• 제17권7호
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• pp.858-865
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• 2014

In the case of system like MES, various sensors collect the data in real time and save it as a big data to monitor the process. However, if there is big data mining in distributed computing system, whole processing process can be improved. In this paper, system to analyze the cause of operation deviation was built using the big data which has been collected from deasphalting process at the two different plants. By applying multivariate statistical analysis to the big data which has been collected through MES(Manufacturing Execution System), main cause of operation deviation was analyzed. We present the example of analyzing the operation deviation of deasphalting process using the big data which collected from MES by using multivariate statistics analysis method. As a result of regression analysis of the forward stepwise method, regression equation has been found which can explain 52% increase of performance compare to existing model. Through this suggested method, the existing petrochemical process can be replaced which is manual analysis method and has the risk of being subjective according to the tester. The new method can provide the objective analysis method based on numbers and statistic.

• 한국산업보건학회지
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• 제24권1호
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• pp.52-58
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• 2014

Objectives: Using laborers participating in the petrochemical factory turnaround process as subjects, this study aims to identify exposure to benzene in the air and examine the relationship between exposure and the excretion of urinary metabolites by measuring concentrations of urinary trans, trans-muconic acid (t,t-MA). Methods: A passive sampler was used to measure the level of benzene in the air. In order to analyze urinary metabolites, the urine of laborers participating in the turnaround process was collected twice daily, both before and after work. In addition, a survey was conducted on work factors and lifestyle habits as factors affecting the concentration of urinary metabolites. Results: During the survey period, benzene was detected in the samples from all workers, and its average concentration was $0.16{\pm}0.22ppm$. The average concentration of t,t-MA after work was $1.20{\pm}1.86mg/g$ creatinine, and the results of analyzing urinary metabolites concentration before and after work showed statistically significant differences(p=0.003). There was also a statistically significant correlation (r=0.52, p=0.002) between benzene in the air and the concentration of after-work urinary t,t-MA. Conclusions: During the turnaround process, the average benzene concentration in workers was $0.16{\pm}0.22ppm$, which was below the exposure limit. However, their average t,t-MA concentration was $1.20{\pm}1.86mg/g$ creatinine, which exceeded the exposure limit of 1mg/g creatinine. The characteristics of turnaround process work require considerations such as underestimating the passive sampler being used and the skin absorption of benzene, and there needs to be a simultaneous assessment of working environment measurements and biological monitoring.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.331-331
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• 2006

Polylactic acid (PLA) is a promising polymer because it can be derived from renewable resources and provides a biodegradable alternative to petrochemical based polymers. This research aims to synthesize PLA, through direct polycondensation and also tries to avoid the occurrence of separation by-product and the use of catalysts in the process. The polymerization of lactic acid was done at three different temperatures $150^{\circ}C,\;180^{\circ}C\;and\;200^{\circ}C$ for 90 h without catalysts and organic solvent. The proposed process provides results that are comparable to those that incorporate catalysts; during polymerization temperature was $180^{\circ}C$ the molecular weight of PLA obtained reached 42448 Da. The thermal properties of PLA analysis by Differential Scanning Calorimetry (DSC).

• 한국기계가공학회지
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• 제11권4호
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• pp.180-184
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• 2012

3-way ball valves have been mostly used for high temperature/high pressure valves using in petrochemical carriers and oil tankers, which requires high quality products with confidentiality and durability. As a larger disaster may be generated by leakage of oil or gas from valves, thus the present research applied a numerical analysis method with thermal-structural coupled field analysis and the performance test. The Max stress by parts was confirmed through thermal-structural coupled field analysis and develop the 3-way ball valve design, which is safe on operating condition. And its performance was verified by carrying out pressure test, leakage test and durability test for the manufactured 3-way ball valves with satisfying it's regulations.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 1999년도 추계학술대회 논문집
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• pp.443-444
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• 1999

악취는 냄새를 유발하는 기체상 물질이 사람의 후각을 자극하여 불쾌감이나 혐오감을 주는 상태를 말한다. 악취물질은 정유공장, 화학공장, 하수처리장, 분뇨 및 축산 폐수처리장, 매립장 등의 다양한 발생원이 있으며, 여러가지 복합된 화합물이 원인이 되어 악취를 유발한다. 단위 물질로서 황화수소(H$_2$S)는 계란 썩는 냄새, 메르캅탄(mercaptan)류는 야채 썩는 냄새, 아민류는 생선냄새 등의 특이한 냄새를 유발하며, 최저 감지값은 물질별로 상당한 차이를 나타내고 있다(이광묵, 1993).(중략)

• 융복합기술연구소 논문집
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• 제11권1호
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• pp.13-18
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• 2021

It is widely accepted that the prevention of global warming requires significant reductions in greenhouse gases, particularly CO₂ emissions. Although fossil fuel-based power plants account for the majority of CO₂ emissions, it is urgent to reduce CO₂ emissions in industries that emit large amounts of CO₂ such as steel, petrochemical, and oil refining. This paper examines the current status of CO₂ emission in the domestic oil refining industry and CO₂ emission sources in each unit process in the oil refining industry. Focusing on the previously developed CO₂ capture process, cases and applicability of greenhouse gas reduction in FCC and hydrogen manufacturing processes, which are major processes constituting the oil refining industry, are reviewed.