• Journal of the Korean Society of Safety
• /
• v.30 no.1
• /
• pp.111-118
• /
• 2015

In this study, we carried out the emissions analysis of CO and $non-CO_2$ for the age-classes of various pine trees(Pinus koraiensis, Pinus densiflora, Pinus rigida Mill., Pinus thunbergii Parl.) to estimate of emission factors of the crown layer and surface layer in the forest fire. We used the thermal characteristic analyzer cone heater and NDIR analyzer in order to measure amount of emission. As a result, the major emissions of Pinus koraiensis were $CO_2$ and $CH_4$ and that of Pinus thunbergii Parl. was only CO. The major emissions of the most of pine trees were NO and $N_2O$. The $CO_2$ emission of Pinus thunbergii Parl. was the highest about as $7.26{\times}10^{-2}{\sim}1.63{\times}10^{-1}g$ and next came Pinus densiflora, Pinus koraiensis, Pinus rigida Mill.. And the CO emission of Pinus thunbergii Parl. was about $5.14{\times}10^{-3}{\sim}6.58{\times}10^{-3}g$ and followed by Pinus densiflora, Pinus koraiensis, Pinus rigida Mill.. The emissions of $CH_4$, NO, and $N_2O$ showed small differences between species and the emission of $CH_4$ was $8.37{\times}10^{-5}{\sim}2.55{\times}10^{-4}g$, and NO was $6.65{\times}10^{-5}{\sim}2.0{\times}10^{-4}g$ and $N_2O$ was $1.42{\times}10^{-4}{\sim}2.09{\times}10^{-3}g$ in all species. Particularly, the emission of Pinus thunbergii Parl. was the highest in all pine trees except $CH_4$.

• Journal of Korean Society for Atmospheric Environment
• /
• v.27 no.1
• /
• pp.41-49
• /
• 2011

The power plants are one of the GHG major source among the sectors of fossil fuel combustion, therefore information of its emission factors is very essential to the establishing control strategies for the greenhouse gas emissions. The $CH_4$ and $N_2O$ concentration from power plants were measured using GC-FID and GC-ECD. The results showed that $CH_4$ emission factor was 0.33 kg/TJ and $N_2O$ emission factor was 0.88 kg/TJ. The $CH_4$ and $N_2O$ emission factors developed in this study were compared with those for IPCC default value and other countries emission factors. The results showed that $CH_4$ emission factor was lower than IPCC default value and Finnish emission factor, but higher than Japanese emission factor. $N_2O$ emission factor was higher Japanese emission factor and IPCC default emission factor however lower than Finnish emission factor. More research is needed on our own emission factors of various energy-consuming facilities in order to stand on a higher position in international negotiations regarding the treaties on climate changes.

• Journal of Climate Change Research
• /
• v.8 no.2
• /
• pp.163-169
• /
• 2017

In this study, Non-$CO_2$ emission factors were estimated for the coal briquette boiler, which is the Korean heating system. As a result, the $CH_4$ and $N_2O$ emission factors of the coal briquette boiler were estimated to be $11.76gCH_4/TJ$ and $7.44kgN_2O/TJ$, respectively. The results showed that $CH_4$ emission factor was 12 times and $N_2O$ emission factor was 5 times higher than IPCC default value. Also the emission factors developed in this study were compared with a precedent study. The results indicated that were similar to open the air inlet of coal briquette stove because the combustion condition of this study was similar to that of coal briquette stove.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.43 no.3
• /
• pp.113-120
• /
• 2011

Precipitated calcium carbonate(PCC), particularly calcite crystal, is extensively used as a pigment, filler or extender in various industries such as paper, paint, textile, detergents, adhesives, rubber and plastics, food, cosmetics, and biomaterials. PCC is conventionally produced through the gas-liquid carbonation process, which consists on bubbling gaseous $CO_2$ through a concentrated calcium hydroxide slurry. This study is aimed to find some factors for controlling the morphology of engineered PCC in lab-scaled mixing batch. The experimental designs were based on temperature variables, $Ca(OH)_2$ concentration, $CO_2$ flow rate, and electrical conductivity. The model of engineered PCC morphology was finally controlled by adjustment of electrical conductivity(6.0~7.0 mS/cm) and $Ca(OH)_2$ concentration(10 g/L). Orthorhombic calcite crystals were mostly created at high concentration and electrical conductivity conditions because the increased ratio of $Ca^{2+}$ and $CO{_3}^{2-}$ ions affects the growth rate of orthorhombic faces. Excess calcium spices were contributed to the growth of faces in calcium carbonate crystal, and the non-stoichiometric reaction was occurred between $Ca^{2+}$ and $CO{_3}^{2-}$ ions during carbonation process.

• Fire Science and Engineering
• /
• v.17 no.1
• /
• pp.33-39
• /
• 2003

The purpose of this study is to evaluate flame retardant performance, thermal stability and toxicity of combustion gases for some commercial wallpapers. ID evaluate flame retardant performance 45 degree combustion experiment method was used and thermal stability was evaluated using DSC and TGA apparatus (OSC-50/Shimadzu, TGA2050/TA Instruments Inc) . Concentrations of CO, $CO_2$, HCN and HCI were measured with (GASTEC/Japan, MSA400 Gas Monitor/Infitron Inc) and toxicity indices using NIST N-Gas Model were applied to evaluate the toxicity of combustion gases. The evaluation produced the following results : First, paper cork and PVC wallpaper treated with flame retardants were found to be suitable for flame retardant performance standards. Second, paper, cork and PVC wallpaper non-treated with flame retardants were shown to be relatively more hazardous because they had greater calorific values and a faster decomposition time than the flame retardant treated wallpapers. Third, the toxicity indices of non-treated wallpapers were found to be higher than those of treated wallpapers, and the toxicity index of PVC wallpapers was higher than those of paper and cork wallpapers.

• Proceedings of the KSME Conference
• /
• 2008.11b
• /
• pp.3079-3084
• /
• 2008

A fast response $CO_2$ analyzer has been developed for measuring the $CO_2$ concentration during transient condition of SI engine. The analyzer is based on the non-dispersive infrared absorption technique, electrical chopping system and water cooling system. The analyzer has good repeatability, linearity and permissible drift characteristic. Besides, it has 18ms with a response to measure the $CO_2$ concentration. The fast response $CO_2$ analyzer was applied to single cylinder SI engine and the $CO_2$ emission was examined during engine start. Simultaneously, the standard exhaust gas analyzer, which has slow response time, was used for considering the engine-out $CO_2$ characteristic. The developed analyzer showed much faster responsive characteristic than that of a standard analyzer and made cycle by cycle exhaust gas analysis possible. The transient engine operating characteristics will be estimated and the transient behaviors on engine-out emission and performance will be improved.

• Proceedings of the KIEE Conference
• /
• 2002.07c
• /
• pp.1403-1406
• /
• 2002

Environmental impact of human activities has become a great concern in most of the countries world-wide, and for years. It has recently focused on potential climate changes due to the increase of green house gases content in the atmosphere. One of these gases is $SF_6$, which is an essential material in electrical applications having excellent dielectric and arc-quenching properties. Though the actual contribution of $SF_6$ to global warming is negligible at present, the control of $SF_6$ emissions seems to be nevertheless imperative. Actually, it is listed in the Kyoto protocol that emissions should not only be duly reported but also the electrical industry which is now the major user of this gas must be able to show that it is possible to use this gas and at the same time preserve the environment. For the development of environmentally-benign electric power equipment and systems, novel gases or gas mixtures are strongly required as the alternatives of $SF_6$ gas. Until now, most research work is focused on the $SF_6/N_2$ mixed gas which is suitable for application in the electrical apparatus with slightly non-uniform fields. Recently, $SF_6/CO_2$ mixed gas also is expected to be promising as a $SF_6$ alternative, especially in highly non-uniform fields and in a gas-impregnated film insulation system. Including these results, the author reviews the research trend or reducing the environmental impact of $SF_6$ gas in this paper.

• Membrane Journal
• /
• v.33 no.3
• /
• pp.94-109
• /
• 2023

1,3-Dioxolane is an exciting material that has attracted widespread interest in the chemical, paint, and pharmaceutical industries as a solvent, electrolyte, and reagent because 1,3-dioxolane is not toxic, carcinogenic, explosive, auto-flammable, and multifunctional, and due to their excellent miscibility in most organic and aqueous solvent conditions. Recently, this material has received increasing attention as a CO₂-selective polymer precursor to separating CO₂ from flue gas and natural gas mixtures. Poly(1,3-dioxolane) (PDXL) possesses higher ether oxygen content than polyethylene oxide (PEO), which demonstrates superior membrane CO₂/N₂ separation properties owing to their polar ether oxygen groups exhibiting strong affinity toward CO₂. Thus, PDXL-based membranes displayed an outstanding CO₂ solubility selectivity over non-polar (N₂, H₂, and CH₄) gases. However, the polar groups of PDXL, like PEO, promote chain packing efficiency and cause polymer crystallization, thereby reducing its gas permeability, which should be improved. In this short review, we discuss the recent advancement and limitations of PDXL membranes in gas separation applications. To conclude, we provide future perspectives for inhibiting the limits of 1,3-dioxolane-based polymers in the CO₂ separation process.

• Journal of the Society of Naval Architects of Korea
• /
• v.48 no.1
• /
• pp.76-83
• /
• 2011

FCAW(Flux Cored Arc Welding) is a widely used welding method in shipbuilding. It also conducts WPS(Welding Procedure Specification) requested by the classification variations of the factors which affect the quality on the welded area such as thickness of base metal, type of welding wire and shielding gas etc. which has to be satisfied. CO2 is commonly used as a shielding gas for FCAW due to the economic point of view. The amount of shielding gas is stated when classification certify WPS. However, the shielding gas is unnecessarily used at the shipyard leaning only on the welder's experience as there are classification standards for using the shielding gas. It causes production cost to rise. Also recently, CO2 is a main contributor for global warming, and large amounts of CO2 are discharged into the atmosphere during shipbuilding processes without any filtration. Therefore it was confirmed by the security of the welded area as a result of conducting the destructive and non-destructive tests with setting up the factors and the standards by using the Taguchi method. Then the FCAW shielding gas's amounts were calculated precisely when assembling a ship. It will be applied to cost reduction and prevention of environmental pollution at the shipyard.

• Membrane Journal
• /
• v.25 no.4
• /
• pp.343-351
• /
• 2015

In this study, we synthesis polyimide with high gas selectivity using 2,2-bis(3,4-carboxylphenyl) hexafluoropropane, 2,4,6-Trimethyl-1,3-phenylenediamine (DAM) and 4,4-Methylenedianiline (p-MDA), and then the asymmetric membrane was fabricated by non-solvent phase separation method. To confirm the property change of the membrane using different solvent, we measured and compared the viscosity of the polymer solution, cloud point and non-solvent phase separation coefficient. The morphology and gas separation property of membrane prepared by phase separation method was confirmed using Field Emission Scanning Electron Microsope and the single gas permeation measurement apparatus. The single gas ($CH_4$, $N_2$, $O_2$, $CO_2$) permeation property and selectivity value of the membrane prepared with NMP was higher than the membrane prepared with DMAc. We confirmed that the gas selectivity of the membrane increased and the permeation property decreased with increasing of the solvent evaporation time.