• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.424-428
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• 2007

In the current most tool using heat and mass balance in a coal gasifier is dependent on commercial code such as STANJAN, CHEMKIN. However, in order to keep the self-reliance technology, it is necessary to develop the original design tool available for comprehension and analysis on the spot. So in this study, its own heat and mass balance program is developed on the assumption that the process in a coal gasifier is adiabatic and quasi-equilibrium. The mass balance is calculated by using the chemical equilibrium principle. Also the heat and mass balance according to main operating factors such as temperature, pressure and O2/Coal ratio, was carried in this tool. This heat and mass balance was verified on the basis of the results simulated in STANJAN, commercial codes using similar logic.

• 한국환경과학회지
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• 제17권4호
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• pp.359-364
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• 2008

PM10 samples were collected from July 2007 to Oct. 2007 at Gwaebopdong(inland area) and Dongsamdong(coastal area), in Busan. This paper investigates the contribution of emission sources to PM10 mass in Busan. Source apportionment results derived from the chemical mass balance(CMB) method. A source profiles applied in this study is organized to minimize the collinearity among sources type via statistical method. Source profiles applied in this study utilized a measured value of fine particle directly sampled from metropolitan area such as Seoul and Incheon, After a CMB modeling, sulfate and nitrate related sources among those contributing to PM10 in Busan showed high contribution by 36.53% in Gwaebopdong and 42.02% in Dongsamdong.

• 한국대기환경학회지
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• 제8권2호
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• pp.112-120
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• 1992

Twenty four metal, nonmetal elements and 4 major anions in total suspended particulates (TSP) collected at two sites in Daejon city from october to december in 1991 by a Hi-vol sampler were thoroughly analyzed by Inductively Coupled Plasma/ Atomic Emission Spectrometry (ICP/AES) and Ion Chromatography (IC). These analyzed data were used to perform a receptor modeling using the Chemical Mass Balance (CMB) for the source apportionment of TSP sample. Approximately 60% TSP weight in industrial complex area was influenced by potential industrial sources and 25% was by heating fuels and automobile emissions, whereas a half of TSP in residential area was influenced by surrounding environment and more than 35% of TSP was influenced by heating fuels. The CMB model provided source apportionment results reasonably and scientifically with a minor limitation.

• Korean Chemical Engineering Research
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• 제53권4호
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• pp.489-495
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• 2015

대기오염물질처리를 위한 생물살수여과법에서 물질전달현상을 이해하기 위한 선행 실험결과를 기초로 각각의 운전조건에서 기체/액체(살수액), 기체/고체(미생물)와 액체/고체에서의 model을 이용하여 물질전달계수를 평가하였다. 생물살수여과법에서 기/액에서는 정상상태물질수지, 그리고 액/고와 기/고에서는 동적물질수지를 이용하여 물질전달 model을 확립하고 그 결과를 고찰하였다. 물질전달 model은 여과탑을 일정크기 구획하여, 각 구획에서 동적 물질수지식을 수치해석 전산코드를 이용해 계산하였다. 동적물질수지식을 이용하여 계산된 결과는 실험결과와 비교하여 생물살수여과법에서 기/액, 기/고, 액/고 각상간의 물질전달계수($K_La$)를 산정하였다. 본 연구에서는 대기오염제어를 위한 생물살수여과법에서 물질전달계수를 결정하기 위한 실험방법개발과 model을 이용하여 물질전달현상을 고찰하였다.

• 에너지공학
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• 제12권4호
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• pp.289-301
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• 2003

매체순환식 가스연소기의 개발을 위해 산화반응기와 환원반응기가 연계된 2탑 가압순환유동층 조건의 50kWth 매체순환식 가스연소기에 대해 물질수지와 에너지수지를 통한 개념설계를 수행하였다. 매체순환식 가스연소기의 물질수지를 통해 산화반응기는 상승관 형태의 고속유동층 조건으로, 환원반응기는 기포유동층 조건으로 반응기 형태를 결정하였다. 물질수지와 에너지수지에 의해 계산된 층내 고체량, 고체순환량 및 반응기 크기는 장치제작 및 실제조업에 적당한 범위의 값을 나타내었으며 산소공여입자의 반응속도는 만족할 만한 수준에 도달하는 것으로 확인되었다. 본 연구의 개념설계 결과에 의하면 매체순환식 가스연소기의 조업조건은 상용 순환유동층의 조업조건과 유사하였으며 실제공정에 적용하기에 무리가 없는 것으로 사료되었다. 본 연구에서 개발된 설계 tool을 이용하여 시스템의 용량, 조업압력, 산소공여입자 중의금속산화물의 함량, 수증기 주입량, 기체유속 및 고체층 높이 등의 변화에 따른 설계 값의 변화를 해석하였으며 이를 통해 조업조건 변화에 따른 시스템의 성능변화를 예측할 수 있었다.

• 분석과학
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• 제30권5호
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• pp.226-233
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• 2017

In general, quantitative chemical analysis in various areas including food, the environment, in vitro diagnostics, etc., requires traceability in order to increase the reliability of the measurements. Measurement traceability is a property of an unbroken chain of comparisons relating an instrument's measurements to SI units. Purity analysis is the first process for establishing traceability to SI units in chemical measurements. The purpose of this study is to develop and validate a method of purity assignment for establishing the traceability of $17{\beta}$-estradiol measurements in an in vitro diagnostics field. The establishment of this method is very important as it can be applied to the development of CRM and to the analysis of the purity of other hormones. The method of assignment of the purity of $17{\beta}$-estradiol was developed using the mass balance method and was validated through participation in an International comparison. In the mass balance method, impurities are categorized into four classes as follows: total related structure impurities, water, residual organic solvents, and nonvolatiles/inorganics. In this study, total related structure impurities were characterized by a gas chromatography-flame ionization detector (GC-FID) and a high-performance liquid chromatography-ultraviolet (HPLC-UV) detector, water content was determined by a Karl-Fisher coulometer, and total residual solvents and nonvolatiles/inorganics were checked simultaneously by thermogravimetric analysis (TGA). The purity of the $17{\beta}$-estradiol was 985.6 mg/g and the expanded uncertainty was 2.1 mg/g at 95% confidence. The developed method can be applied to the development of certified reference materials, which play a critical role in traceability.

• 분석과학
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• 제32권6호
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• pp.225-232
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• 2019

Traceability establishment in chemical measurements is a like a linkage established through an unbroken chain from the measured results to the international system (SI) of units. The primary process for traceability establishment is the purity assignment of a target material to be measured. In this study, we studied the purity assignment of 17α-hydroxyprogesterone (17-OHP). The presence of 17-OHP is indicative of congenital adrenal hyperplasia (CAH) and it builds up due to the deficiency of 21-hydroxylase and 11β-hydroxylase enzyme in the human blood. The purity assignment of 17-OHP was performed by the mass balance method, in which the impurities are categorized into four classes: total related structural impurities, water, residual organic solvents, and nonvolatiles/inorganics. The total related structural impurities were characterized by HPLC-UV; water content was determined by Karl-Fisher coulometer; and the total residual solvents and nonvolatiles/inorganics were determined by TGA. The purity of 17-OHP from a commercial manufacturer was calculated as 993.30 mg/g, and the expanded uncertainty was 0.58 mg/g. The proposed method was validated by uncertainty evaluation and comparing with the actual value of purity.

• 한국수소및신에너지학회논문집
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• 제32권5호
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• pp.374-387
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• 2021

Basic design of 3 MWth chemical looping combustion system for LNG combustion and steam generation was conducted based on the mass and energy balance and the previous reactivity test results of oxygen carrier particles. Process configuration including fast fluidized bed (air reactor), loop seal and bubbling fluidized bed (fuel reactor) was confirmed and their dimensions were determined by mass balance. Then, the external fluidized bed heat exchanger (FBHE) was adopted based on the energy balance to extract heat from the system. The optimum reactor design and operating condition was confirmed with sensitivity analysis by modifying system configuration based on the mass and energy balance.

• 한국대기환경학회지
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• 제22권2호
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• pp.157-166
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• 2006

Ambient TSP at four sites in Korea and soil samples from the source regions of Asian Dust in northern China were collected and analyzed for 15 metal components and 6 water-soluble ions to conduct a chemical mass balance (CMB). CMB receptor model was used to estimate the source contribution of TSP during the Asian Dust period, and the model results showed that China soil was the largest source contributor, accounting for 81% of TSP ($458.2{\mu}g/m^3$). Vehicle emission and geological sources contributed to about 8.8% and 4.4% of aerosol mass, followed by sea salt (1.5%) and secondary aerosol (2.9%). Fuel combustion and industrial process sources were found to be relatively minor contributors to TSP (${\leq}1%$). In addition to source contribution estimates, this study tried to identify the origin of Asian Dust observed in Korea. Among all 13 China soil profiles presented in this study, the most adoptable profile which can project the case well was selected and considered as the origin of the applied case.

• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1139-1143
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• 2006

Various techniques and strategies have been developed for the identification of intracellular metabolic conditions, and among them, isotope balance-based flux analysis with gas chromatography/mass spectrometry (GC/ MS) has recently become popular. Even though isotope balance-based flux analysis allows a more accurate estimation of intracellular fluxes, its application has been restricted to relatively small metabolic systems because of the limited number of measurable metabolites. In this paper, a strategy for incorporating isotope balance-based flux data obtained for a small network into metabolic flux analysis was examined as a feasible alternative allowing more accurate quantification of intracellular flux distribution in a large metabolic system. To impose GC/MS based data into a large metabolic network and obtain optimum flux distribution profile, data reconciliation procedure was applied. As a result, metabolic flux values of 308 intracellular reactions could be estimated from 29 GC/ MS based fluxes with higher accuracy.