• Journal of the Korean Society of Industry Convergence
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• v.23 no.6_2
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• pp.1007-1014
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• 2020

IMO(International Maritime Organization) continues to strengthen environmental regulations on exhaust gases such as CO2, NOx, SOx. As for sulfur oxides, from 1 January 2020, all ships on international voyages must use fuel with a sulfur content of 0.5% or less. Or, it is obligatory to use an exhaust gas treatment device that has the same effect. Shipping companies are using low-sulfur oil, replacing them with LNG fuel, or installing scrubbers that suppress sulfur oxide emissions. In the case of ships using bunker C oil, the load on the engine is lower when entering and departing, so the exhaust gas pressure is lowered and the scrubber cannot be properly utilized. Therefore, diesel oil with low sulfur content is used when entering and leaving the coast. When diesel oil is used, exhaust gas is directly discharged through the control system and piping system, and when bunker C oil is used, sulfur oxides are reduced by scrubbers through other control systems and piping systems to discharge exhaust gas. Accordingly, a company has developed a system called a three-way damper valve that can control exhaust gas emissions while integrating these two control systems and piping systems into one. In this study, the control characteristics of the integrated exhaust gas control system and structural safety against external loads in a high-temperature exhaust gas environment were reviewed.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.2
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• pp.133-141
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• 2011

In this study, different calibration approaches for reduced sulfur compounds (RSCs) were investigated by using thermal desorption coupled with gas chromatography (GC) and pulsed flame photometric detection (PFPD). To evaluate the effects of calibration procedures, gaseous standards of 4 RSCs ($H_2S$, $CH_3SH$, DMS, and DMDS) prepared at 10 ppm level were analyzed at 7 loading injection volumes (40, 60, 80, 100, 160, 240, and 320 ${\mu}L$). The results were then compared with calibration curves made with the Z (zero offset) and N (non-zero offset) method. The concentrations of unknown samples were then quantified by using R (ratio) method in which the slope values are compared between standards and samples. Secondly, in A (average) method, results obtained from a multi-point analysis of unknown samples were also averaged to extract representative values for each sample. Results of both experiments showed that analytical error of low molecular weight components (such as $H_2S$ and $CH_3SH$) was greatly expanded with the Z method. In conclusion, the combined application of N-A method was the more realistic approach to reduce biases in the quantification of RSCs.

• Food Science of Animal Resources
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• v.34 no.3
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• pp.263-272
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• 2014

The effect of the addition of Allium hookeri on the quality of fermented sausage made with meat from sulfur fed pigs was examined, throughout a 60 d ripening period. There were two treatments in animal management: normal feed fed pigs, and sulfur fed pigs given 0.3% sulfur mixed normal feed. Fermented sausage manufactured with meat from normal feed fed pigs, and with meat from sulfur fed pigs, and 1% A. hookeri-containing fermented sausage processed with meat from sulfur fed pigs, were determined at 1 d, 15 d, 30 d, and 60 d. The meat qualities in fermented sausage were measured by DPPH radical scavenging activity (DPPH), $ABTS^+$ radical scavenging activity ($ABTS^+$), total phenolic acids, and total flavonoid contents. Fermented sausage made from pigs that had been fed with 0.3% sulfur was protected from oxidation by reduced free radical, as shown by the significant increase in DPPH and $ABTS^+$ values, compared with fermented sausage made from normal feed fed pigs (p<0.05). A. hookeri-added fermented sausage with sulfur fed pork was shown to increase the values in DPPH, $ABTS^+$, total phenolic acid, and total flavonoid contents, by comparison with both the control sausage, and sausage with sulfur fed pork, at 60 d. These results suggest that A. hookeri in meat from sulfur fed pigs could be a source of natural addition, to increase quality in the food industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1133-1140
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• 2009

The purpose of this study is to determine the most efficient method of removing sulfur dioxide from traditional herbal medicine (hanyak) by slow boiling using a traditional pipkin and an electronic slow boiler. By boiling a hanyak batch containing] 56.4ppm of sulfur dioxide for one hour using a traditional pipkin, 96.7 percent of the sulfur dioxide was removed, while two hours of slow boiling removed ]00 percent. Among different cover materials placed over the pipkin during the slow boiling process including the traditional Korean paper (hanji), regular hanji, filter paper and regular paper, the traditional hanji produced the best performance of sulfur dioxide removal. The initial pH level of the traditional hanji was] 0.03. After one hour of slow boiling hanyak batches in a traditional pipkin covered with traditional hanji, where each batch contained sulfur dioxide of 48ppm, 193ppm, 753ppm and 1,506ppm respectively, the pH level of the hanji cover material was reduced to 9.37, 9.14, 8.9 and 8.03 in respective cases. Our experiment using an electronic medicine slow boiler showed 82.8 percent removal of sulfur dioxide after one hour of slow boiling a hanyak batch containing 753ppm of sulfur dioxide. When hanyak batches were boiled by placing traditional hanji, filter paper, active carbon and hardwood charcoal separately in the middle area within the electronic slow boiler, the sulfur dioxide removal rate was 73.6 percent, 72.8 percent, 73.9 percent and 69.5 percent, respectively. When charcoal was added so as to remove toxic materials from the hanyak, its presence impeded the sulfur dioxide flow and thus reduced the removal efficiency contrary to our anticipation.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.3
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• pp.306-315
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• 2012

In this study, storage stability of reduced sulfur compounds ($H_2S$, $CH_3SH$, DMS, $CS_2$, and DMDS) and $SO_2$ in sampling bags was investigated in terms of two contrasting storage approaches between forward (F) and reverse (R) direction. The samples for the F method were prepared at the same time and analyzed sequentially through time. In contrast, those of reverse (R) method were prepared sequentially in advance and analyzed all at once upon the preparation of the last sample. In addition, relative performance between two different bag materials (PVF and PEA) was also assessed by using 100 ppb standard. The response factors (RF) of gaseous RSC samples were determined by gas chromatography/pulsed flame photometric detector (GC/PFPD) combined with air server (AS)/thermal desorber (TD) system at storage intervals of 0, 1, and 3 days. There is no statistical difference in all RSCs between two storage methods. However, the results of relative recovery indicated 2.58~12.8% differences in compound type between the two storage methods. Moreover, loss rates and storage stability of $H_2S$ and $SO_2$ were considerably affected by bag materials than any other variables. Therefore, some considerations about storage methods (or bag material types) for sulfur compounds are needed if stored by sampling bag method.

• Journal of Welding and Joining
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• v.19 no.5
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• pp.486-491
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• 2001

The effect of S content in welding wires on spattering characteristics and droplet transfer phenomena was studied. In MAG welding using 80%Ar-$20%CO_2$ shielding gas, spattering characteristics and droplet transfer phenomena were varied with S content of wire. Sulfur addition in wire reduced surface tension of droplet and weld pool, and made arc more stable in MAG welding. With increasing S content, the spattering ratio and the ratio of large size spatter ($d{\geq}1.0mm$) were reduced in short circuit transfer mode. In spray transfer mode, spattering ratio, however was increased when sulfur was added more than 0.020wt.% because surface tension of droplets and weld pool was reduced too much even though arc stability was improved.

• Journal of Photoscience
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• v.9 no.2
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• pp.391-393
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• 2002

Effects of illumination with xenon or sulfur lamp on growth of tomato seedlings were studied. Results showed no obvious differences in net photosynthetic rate and apparent quantum efficiency. In comparison with xenon lamp, illumination with sulfur lamp slightly reduced ChI a and ChI b content in leaves, relatively shortened epicotyl and hypocotyl length, but significantly increased anthocyanin content of leaves and promoted root growth of tomato seedling plants.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1335-1338
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• 2005

Thianthrene cation radical perchlorate ($Th^{+{{\cdot}}}{ClO_4}^-$) reacted readily with two isomeric thiols, benzylthiol (1) and 4-methylbenzenethiol (7) in an acetonitrile solution at room temperature. From the reaction of 1, the major products, N-benzylacetamide (4) and benzyl sulfide (5), are characteristic of benzyl carbocations while the minor one, benzyl disulfide (6) implies free radical component of the reaction. It is unprecedented that the formation of a benzyl carbocation was caused by the extrusion of sulfur atoms from benzyl sulfur cations (3). In contrast, from the reaction of 7, only p-tolyl disulfide (10) was obtained from both sulfur radicals and cations. In the reaction of 7 the thio-extrusion was not observed from the p-tolyl sulfur cation (9). A thianthrene cation radical ($Th^{+{{\cdot}}}$) was reduced quantitatively to thianthrene (Th) in both reactions.

• Carbon letters
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• v.3 no.4
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• pp.187-191
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• 2002

In the present research, we prepared the activated carbon (AC) sorbents to remove gas-phase mercury. The mercury adsorption of virgin AC, chemically treated AC and fly ash was performed. Sulfur impregnated and sulfuric acid impregnated ACs were used as the chemically treated ACs. A simulated flue gas was made of SOx, NOx and mercury vapor in nitrogen balance. A reduced mercury adsorption capacity was obtained with the simulated gas as compared with that containing only mercury vapor in nitrogen. With the simulated gas, the sulfuric acid treated AC showed the highest performance, but it might have the problem of corrosion due to the emission of sulfuric acid. It was also found that the high sulfur impregnated AC also released a portion of sulfur at $140^{\circ}C$. Thus, it was concluded that the low sulfur impregnated AC was suitable for the treatment of flue gas in terms of stability and efficiency.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.1
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• pp.52-58
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• 2004

To develop a low emission engine, it is necessary to obtain some better quality of automotive fuels. Sulfur in fuel is transformed to sulfate-laden PM as DOC is applied. Therefore, it necessary to provide low sulfur fuels before DOC is applied. According to the specification of test fuels, flash point, distillation 90％, cetane index are improved but viscosity is decreased in the process of desulfurization. Excessively reduced sulfur may cause to decrease lubricity of fuel and engine performance in fuel injection system. Therefore, this research was emphasized how the application of Bio-diesel affects on the emission characteristics and engine performance under the circumstance of ULSD and DOC.