• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.25 no.2
• /
• pp.31-35
• /
• 2019

Kimchi is a refreshing sour food which gives sour and carbonic acid taste of carbon dioxide produced during the fermentation process. So, carbon dioxide injection was tried to raise carbonic acid taste of kimchi stored in the airtight container. First, carbon dioxide injection times of a given gas supply system were determined experimentally to attain initial concentration of 80% for different solid/liquid ratios. Since carbon dioxide is dissolved in kimchi to decrease its concentration during storage, periodical carbon dioxide injection conditions were needed and determined to keep the $CO_2$ concentration above 70%. For the initial flushing to 80% $CO_2$ concentration in model system filled with water, the injection time ranged from 40 to 89 seconds for free volumes of 2-8 L. $CO_2$ injection conditions for the under-ripened storage at $10^{\circ}C$ consisted of longer time at more frequent cycles for watery kimchi than for Chinese cabbage kimchi. At $0^{\circ}C$ of subsequent ripened stage storage of watery kimchi, the periodical injection at 3 hour interval was required because of continuous dissolution of carbon dioxide. However, Chinese cabbage kimchi did not require subsequent $CO_2$ injection during the ripened state storage and needed only flushing to 80% $CO_2$ at time of the container opening and closing. These results can be used as basic information for the programmed control of $CO_2$ injection in the kimchi container system.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.5 no.1
• /
• pp.11-17
• /
• 1976

Put four different kinds of Jangdongsi, Pasi, Gamsi, and Taebongsi etc. into glass bottle(Fig. 1) of 1150ml and after modulated constitution of air girding this, by means of $CO_2$ the keep in cold storage on $0{\sim}5^{\circ}C$. The results are as follows : 1. $CO_2$ non-addition group was not changed it's own color to four months regardless of kind of persimmons 2. $CO_2$ added test group by double quantity of container was not more rapidly discoloration. 3. One - half quantity of test group added double, same, one-half and one of fifth quantity of container was the most effect, $CO_2$ as the same kind in S. T. P. 4. Taebongsi of test group of four different kinds added one-half quantity of $CO_2$ was maintained effectually possible it's natural color till seven months. 5. In taste, non-addition of $CO_2$ existed astringency taste but addition of $CO_2$ showed sweet taste like a Gamsi since two months of storage.

• Economic and Environmental Geology
• /
• v.51 no.4
• /
• pp.381-392
• /
• 2018

This study examines strategies and implementation plans for commercializing $CO_2$ capture and storage, which is an effective method to achieve the national goal of reducing greenhouse gas. In order to secure cost-efficient business model of $CO_2$ capture and storage, we propose four key strategies, including 1) urgent need to select a large-scale storage site and to estimate realistic storage capacity, 2) minimization of source-to-sink distance, 3) cost-effectiveness through technology innovation, and 4) policy implementation to secure public interest and to encourage private sector participation. Based on these strategies, the implementation plans must be designed for enabling $CO_2$ capture and storage to be commercialized until 2030. It is desirable to make those plans in which large-scale demonstration and subsequent commercial projects share a single storage site. In addition, the plans must be able to deliver step-wised targets and assessment processes to decide if the project will move to the next stage or not. The main target of stage 1 (2019 ~ 2021) is that the large-scale storage site will be selected and post-combustion capture technology will be upgraded and commercialized. The site selection, which is prerequisite to forward to the next stage, will be made through exploratory drilling and investigation for candidate sites. The commercial-scale applicability of the capture technology must be ensured at this stage. Stage 2 (2022 ~ 2025) aims design and construction of facility and infrastructure for successful large-scale demonstration (million tons of $CO_2$ per year), i.e., large-scale $CO_2$ capture, transportation, and storage. Based on the achievement of the demonstration project and the maturity of carbon market at the end of stage 2, it is necessary to decide whether to enter commercialization of $CO_2$ capture and storage. If the commercialization project is decided, it will be possible to capture and storage 4 million tons of $CO_2$ per year by the private sector in stage 3 (2026 ~ 2030). The existing facility, infrastructure, and capture plant will be upgraded and supplemented, which allows the commercialization project to be cost-effective.

• Journal of Mushroom
• /
• v.18 no.1
• /
• pp.115-119
• /
• 2020

This study was conducted to investigate the effect of post-harvest CO₂ treatment on the quality of the 'Gonji-7ho' oyster mushroom. The harvested mushrooms were pre-cooled at 3℃ for 1 day and placed in a gas-tight chamber with 0%, 30%, or 50% of CO₂ concentration for 3 hours at 3℃. Next, 400 g of the oyster mushroom sample was packaged into 20-㎛ thick oriented polypropylene (OPP) film bags and stored at 4℃ for 21 days. Treatment with 30% of CO₂ treatment maintained the highest stipe firmness of the oyster mushrooms during storage. The stipe lightness (CIE L^⁎) was the highest at 14 and 21 days, while the stipe yellowness (CIE b^⁎) was the lowest at 2 and 7 days of storage. Therefore, we concluded that the 30% CO₂ treatment maintained the overall visual quality of the 'Gonji-7ho' oyster mushroom until 17 days of storage at 3℃. Our results suggest that the shelf life of 'Gonji-7ho' oyster mushroom could be extended by the postharvest application of 30% CO₂ for 3 hours during low temperature storage.

• The Journal of Engineering Geology
• /
• v.28 no.2
• /
• pp.207-215
• /
• 2018

Almost all countries of the world have recently made great efforts to reduce green-house gases to alleviate the global warming threatening human survival, because a huge amount of carbon dioxide as one of the main green-house gases has been emitted from the combustion processes of fossil fuels such as coal and oil. $CO_2$ capture and storage (CCS) technology is a representative method to diminish the green-house gases, and actively investigated by many countries. This study focuses on the design and construction of a high pressure $CO_2$ injection facility to store it to underground, which is the first $CO_2$ injection in Korea following the steps of the $CO_2$ capture from large $CO_2$ emission sources and transportation to the sea. Injection tests of $CO_2$ on the platform on the sea were carried out in Yeongil Bay of Pohang city in the early 2017. Thus, we were able to perceive the necessary operating conditions of the injection facility, injection characteristic, and knowhow of the injection facility. The results obtained from the injection test shall be utilized for facility upgrades and scale-ups.

• Journal of Energy Engineering
• /
• v.11 no.1
• /
• pp.34-46
• /
• 2002

Carbon accounting is a key issue in the discussions on global warming/CO$_2$mitigation. This paper applies both the IPCC Approach and the NEAT (Non-Energy use Emission Accounting Tables) model, a bottom-up approach, to estimate the potential CO$_2$ emissions (carbon storage) originating from the non-energy use as to assess the actual CO$_2$ emissions (carbon release) from the use of fossil fuels in Korea. The current Korean carbon accounting seems to overestimate the potential CO$_2$ emissions and with it to underestimate the actual CO$_2$ emissions. The estimation shows that the potential CO$_2$ emissions calculated according to the IPCC Approach are lower than those calculated using the NEAT model. This is because the IPCC default storage fraction for naphtha seems to be low for the Korean petrochemical production structure, on the one hand and because the IPCC Approach does not consider the trade with short life petrochemical products, on the other hand. This paper shows that a bottom-up approach like the NEAT model can contribute to overcome some of limitations of the IPCC guidelines, especially by considering the international trade with short life petrochemical products and by estimating the storage fractions of fossil fuels used as feedstocks for the country in consideration. This paper emphasizes the importance of accurate energy statistics for carbon accounting.

• Analytical Science and Technology
• /
• v.36 no.5
• /
• pp.236-249
• /
• 2023

Carbon dioxide (CO₂) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO₂ capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO₂ storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO₂ sorption properties. We find that Schiff base complexes exhibit high CO₂ adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressure on the CO₂ adsorption properties of Schiff base complexes. The Schiff bases possessed tiny Brunauer-Emmett-Teller surface areas (4.7-19.4 m²/g), typical pore diameters of 12.8-29.43 nm, and pore volumes ranging from 0.02-0.073 cm³/g. Overall, our results suggest that synthesized complexes have great potential as an effective media for CO₂ storage, which could significantly reduce greenhouse gas emissions and contribute to mitigating climate change. The study provides valuable insights into the design of novel materials for CO₂ capture and storage, which is a critical area of research for achieving a sustainable future.

• Korean Journal of Food Science and Technology
• /
• v.24 no.6
• /
• pp.603-609
• /
• 1992

To investigate the effect of polyethylene film packaging and $CO_2$ treatment on tomatoes during storage, the gas composition in film, weight loss, the changes of color, hardness and several components were measured. The concentrations of $CO_2$ and $O_2$ in film were changed rapidly in early stage, but it kept a constant level after 7 days of storage. In 0.06 mm polyethylene film, $CO_2$ and $O_2$ concentration was kept a level of $4{\sim}6%$ respectively. The increase in $C_2H_2$ concentration was delayed in thick and $CO_2$ treated film. The rate of weight loss was 4% in non-packed tomatoes, but it recorded about 1% in 0.06 mm polyethylene film. Titratable acidity, pH and soluble solids were changed slightly, but the obvious differents were not observed according to film thickness and $CO_2$ treatment. The value of tomatoes was increased but L and b values were not changed greatly during storage. These color changes were restricted by 0.06 mm film and $CO_2$ treatment. The firmness and content of ascorbic acid were reduced during storage but it restrained by $CO_2$ treatment and film packaging. Sugar of tomatoes were composed of glucose, fructose and a very small amount of sucrose, and they were changed little during storage.

• Korean Chemical Engineering Research
• /
• v.51 no.5
• /
• pp.602-608
• /
• 2013

Gas hydrate studies are attracting attention of many researchers as an innovative, economic and environmentally friendly technology when it is applied to $CO_2$ capture, transport, and storage. In this study, we investigated whether $CO_2$ hydrate shows the self-preservation effect or not, that is the key property for developing a novel $CO_2$ transport/storage method. Especially the degree of self-preservation effect for $CO_2$ hydrate was studied according to the particle size of $CO_2$ hydrate samples. We prepared three kinds of $CO_2$ hydrate samples varying their particle diameter as millimeter, micron and nano size and measured their change of weight at $-15{\sim}-30^{\circ}C$ under atmospheric pressure during 3 weeks. According to our experimental result, the lower temperature, larger particle size, and compact structure for higher density are the better conditions for obtaining self-preservation effect.

• Journal of the Korean Geotechnical Society
• /
• v.39 no.11
• /
• pp.63-70
• /
• 2023

Underground carbon dioxide (CO₂) storage emerges as a pivotal strategy for mitigating atmospheric CO₂ emissions and addressing global warming concerns. This study investigates techniques to optimize storage efficiency in aquifers, which stand out for their superior capacity compared to other geological layers. The focus is on the application of nonionic and anionic surfactants to enhance CO₂ storage efficiency within confined spaces. A specialized micromodel facilitating fluid flow observation was employed for the evaluation. Experimental results revealed a noteworthy minimum 40% increase in storage efficiency at the lowest injection rate when utilizing nonionic and anionic surfactants, in comparison to pure water injection. Interestingly, no significant variations in storage efficiency were observed based on the ionicity and concentration of the surfactants under investigation. These findings have implications for guiding the selection and concentration determination of surfactants in future underground CO₂ storage endeavors.