• Korean Journal of Environmental Agriculture
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• v.8 no.1
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• pp.7-16
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• 1989

Application of steam distillation on the analysis of pesticide residue in soil, water and crops was studied using the nitrogen distillation apparatus. Most pesticides which were extracted by organic solvents could be analyzed by the steam distillation method. For instance, distillations of PCNB, ${\gamma}-BHC$, ${\alpha}-or$ ${\beta}-endosulfan$, IBP, diazinon, fenthion, fenitrothion, alachlor, butachlor, pretilachlor, metolachlor, pendimethalin, benthiocarb and molinate were possible, but not simazine, atrazine and nitrofen. The optimum volume of distillate for a sufficient extraction of pesticide varied according to kind of pesticide. In general, the volume needed was little for carbamate, but much more for organochlorine. When the definite amount of distillate was obtained and then the condenser was washed by acetone, the optimum volume of distillate was less. Using the steam distillation method, the amount of organic solvent needed for one extraction of pesticide from soil, water and vegetable was less than the conventional solvent extraction method, and the analytical procedure became simpler. The process of concentration and clean up was mostly unnecessary, although a ghost peak was apparent in the gas chromatogram according to the kind of materials distilled.

• Analytical Science and Technology
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• v.23 no.1
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• pp.45-53
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• 2010

For the determination of chlorine in uranium compound, analytical methods by using a steam distillation and a pyrohydrolysis have been developed. The steam distillation apparatus was composed of steam generator, distilling flask and condenser etc. The samples were prepared with an aliquot of LiCl standard solution and a simulated spent nuclear fuel. A sample aliquot was mixed with a solution containing 0.2 M ferrous ammonium sulfate-0.5 M sulfamic acid 3 mL, phosphoric acid 6 mL and sulfuric acid 15 mL. The chloride was then distilled by steam at the temperature of $140^{\circ}C$ until a volume of $90{\pm}5\;mL$ is collected. The pyrohydrolysis equipment was composed of air introduction system, water supply, quartz reaction tube, combustion tube furnace, combustion boat and absorption vessel. The chloride was separated from powdered sample which is added with $U_3O_8$ accelerator, by pyrohydrolysis at the temperature of $950^{\circ}C$ for 1 hour in a quartz tube with a stream of air of 1 mL/min supplied from the water reservoir at $80^{\circ}C$. The chlorides collected in each absorption solution by two methods was diluted to 100 mL and measured with ion chromatography to determine the recovery yield. For the ion chromatographic determination of chlorine in molten salt retained in a metal ingot, the chlorine was separated by means of pyrohydrolysis after air and dry oxidation, and grinding for the sample.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.05a
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• pp.112-116
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• 2001

In the paper, desalination technology for a barge mounted plant is presented. Desalination system on a barge needs high efficiency, smaller space, and stability. Therfore 4-effect distillation system (capacity of 50ton/day) is designed and constructed. During operation, detailed investigation of different opereation parameters is carried. This paper discusses about product water flowrate and recover ratio with different steam flow rate and feed water rate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3764-3773
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• 2012

In this study, modeling and optimization works were completed for the separation of 99.9 mol% of methyl ethyl ketone from water through a pressure-swing distillation process since the azeotropic composition varies very sensitively with the change of system pressure. PRO/II with PROVISION release 9.1 was used for the computer simulation and Wilson activity coefficient model was chosen as a modeling equation. A pressure-swing distillation process can be classified into a low-high pressure columns configuration and a high-low pressure columns configuration. In this work, each configurations were optimized for the minimization of steam consumptions, respectively and were compared.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.3
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• pp.238-242
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• 2015

A steam jet vacuum system that will be implemented in a multi-effect desalination plant is numerically investigated. The objective of this study is to numerically investigate the performance characteristic of the steam jet vacuum system for the sea water distillation process. The effects of design parameter such as nozzle size and converging duct angle are discussed in order to get a better understanding of flow characteristics inside the steam ejector and subsequently pave the way for more optimum designs. The simulation results have been in good agreement with experimental data and have well reproduced the shock train phenomena of the throat region.

• Journal of environmental and Sanitary engineering
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• v.11 no.2
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• pp.65-73
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• 1996

The objective of this study is to investigate the removal efficiency of volitile organic compounds in soil, and the mechanism of desorption by bench scale microwave heating, Silt soil used for experiment and was impregnated with toluene, tetrachloroethylene, o-xylene and p-dichlorobenzene and the microwave treatment was conducted in a modified domestic microwave oven : 2450MHz, 700W. According to the results of the research the removal efficiency was improved with increasing water contents and the soil temperature appeared to plateau period extending to 2-3minutes corresponds to the temperature a which steam distillation was expected. The value of removal rate constant (k) were calculated on dry and moisty silt soil, respectively, which showed linear with increasing microwave heating time. Therefore, addition of a certain amount of water to the contaminated soil can efficiently enhance the ability of the soil to absorb microwave energy and promote the evaporation of the volitile contaminants.

• Korean Journal of Food Science and Technology
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• v.4 no.1
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• pp.1-5
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• 1972

This investigation was primarily carried out to establish the optimum conditions for the separation of sorbic acid, as an enzyme inhibitor, from dry mountain ash berries. The berries were crushed to $35{\sim}40\;mesh$, and leached with water to produce a reddish juice, which was concentrated to syrup after evaporation. Parasorbic acid was separated from the syrup by steam distillation in the presence of acid. In this study, the optimum experimental results for separation of parasorbic acid were obtained as follows : (1) the most applicable leaching time of the dry ash berries was about 6 hours at room temperature and less than 4 hours at $40^{\circ}C$ and (2) in steam distillation, after removal of malic acid, addition of 30 ml of sulfuric acid per 50 ml of syrup extracted from 100 g of the ash berries was very adequate. The purity of sorbic acid obtained experimentally through the isomerization technique was qualitatively examined by spectrophotometeric, paper chromatographic, and melting point measurements.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.2
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• pp.171-178
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• 2014

The purpose of this study was to analyse the volatile components of Thymus magnus Nakai extracted by different extraction methods and reproduce scent close to original plant based on the results. For this purpose, the essential oil of T. magnus was extracted by supercritical fluid extraction (SFE), water and steam distillation (WSD) and simultaneous steam distillation and extraction (SDE) methods. The compositions of the essential oil were analyzed by gas chromatography-mass spectrometry (GC-MS). Consequently, linalool (0.1%) and trans-sabinene hydrate (0.9%) contents in the essential oil extracted by SFE method of $40^{\circ}C$ - 400 bar condition were relatively higher than compositions of the essential oil extracted by different conditions. The contents of borneol (3.82%), terpinen-4-ol (0.3%) and caryophyllene oxide (2.2%) were relatively higher at $50^{\circ}C$ - 400 bar and the contents of ${\beta}$-bisabolene (5.88%), 1-octen-3-ol (0.31%), caryophyllene (2.91%), p-cymene (2.04%) and ${\gamma}$-terpinene (0.52%) were extracted relatively higher at $50^{\circ}C$ - 300 bar. The compositions of the essential oil extracted by SFE method of $50^{\circ}C$ - 200 bar condition contained relatively higher contents of thymol (77.63%) and carvacrol (5.65%). The contents of ${\alpha}$-bisabolol (0.17%), caryophyllene (6.46%), cis-${\alpha}$-bisabolene (1.52%) and ${\beta}$-bisabolene (20.65%) in the essential oil extracted by WSD method were relatively higher than compositions of the essential oil extracted by SFE method, and by SDE method we couldn't obtained essential oil. The results of this study could be utilized to reproduce scent close to original scent of T. magnus.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.386-395
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• 1995

This study was carried out to investigate the volatile constituents change according to extraction methods, parts and heating methods. The research results are as follows: 23 kinds of components were extracted by steam distillation method; 8 by head space method; 16 by ether extraction method; 9 by Tenax-GC. This fact indicated that volatile constituents differ depending upon the extracting method. When the volatile constituents were extracted by steam distillation method and analyzed by GC-MSD, the content of the volatile constituents was 41.71 mg％ in the stem and 85.37 mg％ in the leaf. A total of 23 components - 14 kinds of hydrocarbon, 5 of aldehyde, 4 of alcohol- were detected in the stem. A total of 31 components - 21 kinds of hydrocarbon, 5 of aldehyde, 4 of alcohol and 1 of ester were detected in the leaf. The leaf had comparatively more varied volatile constituents than the stem. In the stem, the octanal content was highest and the contents of limonene, sabinene, -terpinene and -myrcene were higher; in the leaf, the content of octanal was highest and the contents of isobicyclogermacrene, limonene, -farnesene, undecaethiol, -terpinene, sabinene, elemene, -myrcen were higher. These were the major volatile constituents of the water d.opwort. The volatile constituent formation changed as the water dropwort was heated. The volatile constituents of the water dropwort heated in 1000 $m\ell$ were the most similiar to those of the raw water dropwort, and volatile constituent content was highest.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.238-243
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• 1994

Changes of lipid components in modified oleoresin during cooking at high temperature were investigated. In preparation of the modified oleoresin, dried red pepper was milled to 100 mesh of size particle and extracted oily compounds by reduced pressure steam distillation . The rest part was reextracted and concentrated and concentrated. The extracts were combined. The same volume of water and 4% of polyglycerol condensed ricinoleate (PGDR) were added to the combined extract, and emulsified to make oleresin red pepper. Non-polar lipid components were quantified 3 times higher in the oleoresin than polar lipid components . The components of non-polar lipd was mainly triglyceride comprising 75.8%. The level of phosphatidyl choline and phosphatidyl ethanolamine were 38.6and 26.1%, respectively. linoleic acid was distinctively abundant (63.1%) and followed by palmitic acid, oleic acid, linolenic acid and stearic acid in the oleoresin. Oxidation of lipid at high temperature was principally affected by temperature rather than oxygen existence . With the result of oxidation , palmitic acid and myristic acid increased, however, oleic acid, linoleic acid, and linolenic acid decreased.