• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.391-399
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• 2023

Recently, low-temperature pyrolysis technology has been studied as a recycling method for waste plastic. Low-temperature pyrolysis technology for waste plastic produces pyrolysis oil that can be used as an energy resource, but solid residue remains. Waste plastic pyrolysis residues are mostly landfilled due to their limited use. In this study, it is investigated that mixed waste plastic pyrolysis residues could be recycled into activated carbon. It was confirmed that the fixed carbon content of the residue was 33.69 % from proximate Analysis. Chemical activation was used to manufacture activated carbon. KOH was used as an activator. To investigate the effect of the mixing ratio of KOH and residue, samples were mixed at ratios of 0.5, 1.0, and 2.0. The mixed sample was chemically activated at an activation temperature of 800 ℃ for 1 hour. As a result of analyzing the characteristics of activated carbon through BET, it was confirmed that the specific surface area increased as the mixing ratio of KOH increased.

• Journal of Korean Society on Water Environment
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• v.40 no.3
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• pp.131-139
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• 2024

This study investigated the chemical properties of Organic Soil Amendments (OSAs) made from organic waste. It also assessed the effectiveness of using these OSAs in the soil layer of Green Infrastructure (GI) to reduce stormwater runoff and non-point source pollutants. The goal was to improve the national environmental value through resource recycling and contribute to the circular economy transformation and carbon neutrality of urban GI. The OSAs used in this study consisted of spent coffee grounds and food waste compost. They were found to be nutrient-rich and stable as artificial soils, indicating their potential use in the soil layer of GI facilities. Applying OSAs to bio-retention cells and permeable pavement resulted in a reduction of approximately 11-17% in stormwater runoff and a decrease of about 16-18% in Total Phosphorus (TP) discharge in the target area. Increasing the proportion of food waste compost in the OSAs had a positive impact on reducing stormwater runoff and pollutant emissions. This study highlights the importance of utilizing recycled resources and can serve as a foundation for future research, such as establishing parameters for assessing the effectiveness of GI facilities through experiments. To enable more accurate analysis, it is recommended to conduct studies that consider both the chemical and biological aspects of substance transfer in OSAs.

• Journal of Microbiology and Biotechnology
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• v.33 no.11
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• pp.1403-1411
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• 2023

Carbon dioxide (CO₂) is the most abundant component of greenhouse gases (GHGs) and directly creates environmental issues such as global warming and climate change. Carbon capture and storage have been proposed mainly to solve the problem of increasing CO₂ concentration in the atmosphere; however, more emphasis has recently been placed on its use. Among the many methods of using CO₂, one of the key environmentally friendly technologies involves biologically converting CO₂ into other organic substances such as biofuels, chemicals, and biomass via various metabolic pathways. Although an efficient biocatalyst for industrial applications has not yet been developed, biological CO₂ conversion is the needed direction. To this end, this review briefly summarizes seven known natural CO₂ fixation pathways according to carbon number and describes recent studies in which natural CO₂ assimilation systems have been applied to heterogeneous in vivo and in vitro systems. In addition, studies on the production of methanol through the reduction of CO₂ are introduced. The importance of redox cofactors, which are often overlooked in the CO₂ assimilation reaction by enzymes, is presented; methods for their recycling are proposed. Although more research is needed, biological CO₂ conversion will play an important role in reducing GHG emissions and producing useful substances in terms of resource cycling.

• Journal of Animal Reproduction and Biotechnology
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• v.39 no.3
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• pp.212-219
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• 2024

Background: This study explores the potential of discarded male layer embryos as a sustainable and non-GMO cell source for cultivated chicken meat production. The research aims to identify efficient methods for isolating muscle progenitor cells (MPCs) with high proliferative potential by conducting transcriptome analysis on thigh muscle tissues from both male and female chick embryos. Methods: Transcriptome analysis was performed on the thigh muscle tissues of male and female chick embryos, aged 12-13 days, (n = 4 each), to investigate the gene expression profiles and identify strategies for efficiently isolating MPCs. This approach aims to pinpoint techniques that would allow for the selection of MPCs with optimal growth and proliferation capabilities. Results: Using heatmap, hierarchical clustering, and multidimensional scaling (MDS), we found no significant sex-based differences in gene expression, except for the overexpression of the female-specific gene LIPBLL. The expression of muscle stem cell factors, including PAX3, PAX7, and other myogenic regulatory genes, showed no significant variation. However, to recover MPC-rich cells isolated from male thigh muscle, we found that by the pre-plating 7 stage, myogenesis-related genes, MYHs and MUSTN1 were minimally expressed, while the cell cycle arrest gene CDKN1A sharply increased. Conclusions: Our findings suggest that simple cell isolation directly from tissue is a more scalable and efficient approach for cultivated meat production, compared to labor-intensive pre-plating methods, making it a viable solution for sustainable research and resource recycling.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.11
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• pp.611-617
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• 2016

Remanufacturing that is the rebuilding of a product to specifications of the original manufactured product by collecting used-product, completely disassembling, cleaning and repairing or replacing with a new part and reassembling has been received attention in aspects of resource, recycling because it is a great environmental improvement. Remanufacturing is the rebuilding of a product to specifications of the original manufactured product by collecting used-product, completely disassembling, cleaning and repairing or replacing with a new part and reassembling. With a great environmental improvement and resource recycling and conservation, many studies were conducted. Up to date, remanufacturing activities are mainly applied to automobile parts and printer toner cartridge in South Korea. However, remanufacturing of rental product is not well conducted although rental products are collected in good condition and could be remanufactured in the same condition as a new product. Therefore, in this study, we conducted life cycle assessment (LCA) to an air cleaner product that is one of rental products. This study attempts to identify the processes in new products and remanufacturing life cycles that contribute the most environmental impacts. The results show that air cleaner remanufacturing could reduce about 20% of environmental impacts compared to new product. The greatest benefit related to environmental impact is with regard to ozone layer depletion potential (ODP), which is reduced by 94%. In the life cycle of air cleaner, raw material extraction stage had the most environmental impacts, especially with regard to abiotic depletion potential (ADP) and global warming potential (GWP). In the environmental impacts in each part, the ABS power had the highest environmental impacts.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.4
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• pp.15-22
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• 2017

Application of organic resources to agricultural land can increase crop yield by improving soil characteristics. The objective of this study was to evaluate effect of crop yield and soil physical properties including aggregate stability to application of organic resources in upland. The soybean was cultivated in a sandy loam field and a clay loam field located at Suwon and a sandy loam field located at Pyeongchang. The organic resources used in this study were rice straw compost (RSC), composted pig manure with sawdust (CPIG), composted poultry manure with sawdust (CPM), and cocopeat applied before sowing crop. Application rate of organic resources was determined based on carbon content and water content. The inorganic fertilizers were applied based on soil testing. In addition, the decomposition of RSC, CPIG, and cocopeat was characterized by isothermal incubation with sandy loam soil. The decomposition rate was highest for RSC followed by CPIG and cocopeat. Organic resource application increased yield of soybean, which effect was greater in clay loam than in sandy loam. In addition, increase in gas phase proportion by organic resource application was distinct in clay loam soil compared with sandy loam soil. In terms of aggregate stability, increasing effect was more obvious in sandy loam soils than in a clay loam soil. The highest yield was observed in RSC treatment plots for all the fields. Improvement of soybean yield and soil physical characteristics by cocopeat was not as much as that of the other organic resources. The results implied that RSC could be recommended for promoting aggregate stability and crop yield in upland cultivation.

• Korean Journal of Environment and Ecology
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• v.38 no.1
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• pp.90-107
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• 2024

This study analyzed the status of urban agricultural regulation of metropolitan governments on supporting multi-dimensional values to suggest a direction for improving urban agriculture regulations. Moreover, a Delphi survey was conducted to derive ways to identify improvement opportunities for functions that showed relatively insufficient support for urban agricultural regulations. As a result of the study, 12 out of 17 metropolitan governments and 116 of 226 municipalities have enacted urban agricultural regulations. However, the enactment of urban agricultural regulations has generally declined since 2011. Analysis of the contents of the urban agricultural regulations showed that they focused on matters relating to the creation and expansion of the foundation of urban agriculture. Among the multi-dimensional values of urban agricultural regulations, the foundation for supporting the securing of green spaces and utilizing food production functions was most widely available. On the other hand, the foundation for support of resource recycling, healing and health, social welfare, economic imbalance mitigation, and job creation functions has been shown to be relatively insufficient. A Delphi survey conducted to determine potential measures to improve urban agricultural regulations to support these functions found that 17 of the 18 ordinance improvement measures were valid. Therefore, to revitalize the multi-dimensional values of urban agriculture, it is first necessary to enact new ordinances. Also, to revitalize the multi-dimensional values of urban agriculture evenly, it is necessary to revise the ordinances to include resource recycling, healing and health, social welfare, mitigation of economic imbalances, and job creation functions. In this process, the development of urban agriculture technology, legal review of various urban farming spaces, and fostering of industries related to urban agriculture are necessary. Above all, steady interest in the multi-dimensional values of urban agriculture and the efforts of local governments to foster urban agriculture must be supported.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.3
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• pp.95-111
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• 2004

This research sought to determine the status of the installation and operation of composting facilities of domestic public resource-making facilities and come up with corresponding improvement measures. The composting facilities were the most extensively installed of related facilities with over a 0.5 ton treated volume per day. The monthly and yearly carry-in volume of food waste were found to stand at 1,101.7 tons per day and 930.9 tons per day, thus falling short of the average planned volume of 1,270.9 tons. Many composting facilities, which were installed in areas for which factory registration were not approved, did not get approvals. Composting facilities underwent operation stoppage mainly due to faulty fermentation and crushing equipment. Mainly metals contained in food waste caused faults to the crushing equipment, thus requiring a facility designing against faults and corrosion. The initial water content was found to stand at 50-60%, thus complying with the requirement. However, since the composting food waste had an appropriate mixture of sawdust, food waste, and returned compost, it should meet the initial conditions. For fermentation facilities, the duration time for fermentation was 15 days, and post-fermentation tanks required 21 days of duration time, thus establishing the minimum criteria. However, some facilities did not meet the requirements, taking more time in decomposition, thus suggesting a need to determine the duration time according to facilities. In composting food waste, microorganism-based thermal oxidizer-operated fermentation tanks should be used to ensure an economic operation. On the contrary, 14 out of 25 survey targets heated fermentation tanks in any form. These thermal facilities contain the growth of bacteria, lowering chemical reaction in composting; thus composting facilities should be basically designed to use microorganism-based thermal oxidizers in drying water. An average daily volume of food waste and supplementary materials that was injected in producing compost was 22.8 tons. This volume produced 7.3 tons of compost per day, decreasing 68%. Properties of produced compost were analyzed by its color, absence or presence of remaining decomposition heat, and smell, to assess the quality. As a result, the composting process was not properly installed nor operated in about 50% of composting facilities. Compost should be produced to be soil-friendly.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.4
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• pp.31-37
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• 2010

Livestock manures have a potential to be a valuable resource with an efficient treatment. In Korea, 42 million tons of livestock manure were generated in 2008, and 84 % of them were used for compost and liquid fertilizer production. Recently recycling of livestock manure for biogas production through anaerobic digestion is increasing, but its utilization in agriculture is still uncertified. In this study, there was applied co-digestate to the paddy for rice cultivation based on N supplement. Co-digestate was fertilizer fermented with pig slurry and food waste combined with the ratio of 70:30(v:v) in its volumetric basis. For assessing the safety of co-digestate, it was monitored the contents of co-digestate for seasonal variation, resulted in no potential harm to the soil and plant by heavy metals. The results showed that soil applied with co-digestate was increased in exchangeable potassium, copper and zinc mainly due to the high rate of pig slurry in co-digestate applied. Considering high salt content due to the combination with food waste, strict quality assurances are needed for safe application to arable land though it has valuable fertilizer nutrient. Leachate after treatment showed that the concentration of nitrate nitrogen washed out within two weeks. Considering the salt accumulation results in soil, it is highly recommended that the application rate of co-digestate should not exceed the crop fertilization rate based on N supplement. With these results, it was concluded that co-digestate could be used as an alternative fertilizer for chemical fertilizer. More study is needed for the long-term effects of co-digestate application on the soil and water environment.

• Journal of Global Scholars of Marketing Science
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• v.20 no.1
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• pp.59-69
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• 2010

Green or an environmental consciousness has been a major issue for businesses and government offices, as well as consumers, worldwide. In response to this movement, the Korean government announced, in the early 2000s, the era of "Green Growth" as a way to encourage green-related business activities. The Korean fashion industry, in various levels of involvement, presents diverse eco-friendly products as a part of the green movement. These apparel products include organic products and recycled clothing. For these companies to be successful, they need information about who are the consumers who consider green issues (e.g., environmental sustainability) as part of their personal values when making a decision for product purchase, use, and disposal. These consumers can be considered as eco-sumers. Previous studies have examined consumers' purchase intention for or with eco-friendly products. In addition, studies have examined influential factors used to identify the eco-sumers or green consumers. However, limited attention was paid to eco-sumers' disposal or recycling behavior of clothes in comparison with their green product purchases. Clothing disposal behaviors are ways that consumer can get rid of unused clothing and in clue temporarily lending the item or permanently eliminating the item by "handing down" (e.g., giving it to a younger sibling), donating, exchanging, selling, or simply throwing it away. Accordingly, examining purchasing behaviors of eco-friendly fashion items in conjunction with clothing disposal behaviors should improve understanding of a consumer's clothing consumption behavior from the environmental perspective. The purpose of this exploratory study is to provide descriptive information about Korean eco-sumers who have ecologically-favorable lifestyles and behaviors when buying and disposing of clothes. The objectives of this study are to (a) categorize Koreans on the basis of clothing disposal behaviors; (b) investigate the differences in demographics, lifestyles, and clothing consumption values among segments; and (c) compare the purchase intention of eco-friendly fashion items and influential factors among segments. A self-administered questionnaire was developed based on previous studies. The questionnaire included 10 items of clothing disposal behavior, 22 items of LOHAS (Lifestyles of Health and Sustainability) characteristics, and 19 items of consumption values, measured by five-point Likert-type scales. In addition, the purchase intention of two eco-friendly fashion items and 11 attributes of each item were measured by seven-point Likert type scales. Two polyester fleece pullovers, made from fabric created from recycled bottles with the PET identification code, were selected from one Korean brand and one US imported brand among outdoor sportswear brands. A brief description of each product with a color picture was provided in the survey. Demographic variables (i.e., gender, age, marital status, education level, income, occupation) were also included. The data were collected through a professional web survey agency during May 2009. A total of 600 final usable questionnaires were analyzed. The age of respondents ranged from 20 to 49 years old with a mean age of 34 years. Fifty percent of the respondents were males and about 58% were married, and 62% reported having earned university degrees. Principal components factor analysis with varimax rotation was used to identify the underlying dimensions of the clothing disposal behavior scale, and three factors were generated (i.e., reselling behavior, donating behavior, non-recycling behavior). To categorize the respondents on the basis of clothing disposal behaviors, k-mean cluster analysis was used, and three segments were obtained. These consumer segments were labeled as 'Resale Group', 'Donation Group', and 'Non-Recycling Group.' The classification results indicated approximately 98 percent of the original cases were correctly classified. With respect to demographic characteristics among the three segments, significant differences were found in gender, marital status, occupation, and age. LOHAS characteristics were reduced into the following five factors: self-satisfaction, family orientation, health concern, environmental concern, and voluntary service. Significant differences were found in the LOHAS factors among the three clusters. Resale Group and Donation Group showed a similar predisposition to LOHAS issues while the Non-Recycling Group presented the lowest mean scores on the LOHAS factors compared to the other segments. The Resale and Donation Groups described themselves as enjoying or being satisfied with their lives and spending spare-time with family. In addition, these two groups cared about health and organic foods, and tried to conserve energy and resources. Principal components factor analysis generated clothing consumption values into the following three factors: personal values, social value, and practical value. The ANOVA test with the factors showed differences primarily between the Resale Group and the other two groups. The Resale Group was more concerned about personal value and social value than the other segments. In contrast, the Non-Recycling Group presented the higher level of social value than did Donation Group. In a comparison of the intention to purchase eco-friendly products, the Resale Group showed the highest mean score on intent to purchase Product A. On the other hand, the Donation Group presented the highest intention to purchase for Product B among segments. In addition, the mean scores indicated that the Korean product (Product B) was more preferable for purchase than the U.S. product (Product A). Stepwise regression analysis was used to identify the influence of product attributes on the purchase intention of eco product. With respect to Product A, design, price and contribution to environmental preservation were significant to predict purchase intention for the Resale Group, while price and compatibility with my image factors were significant for the Donation Group. For the Non-Recycling Group, design, price compatibility with the factors of my image, participation to eco campaign, and contribution to environmental preservation were significant. Price appropriateness was significant for each of the three clusters. With respect to Product B, design, price and compatibility with my image factors were important, but different attributes were associated significantly with purchase intention for each of the three groups. The influence of LOHAS characteristics and clothing consumption values on intention to purchase Products A and B were also examined. The LOHAS factor of health concern and the personal value factor were significant in the relationships with the purchase intention; however, the explanatory powers were low in the three segments. Findings showed that each group as classified by clothing disposal behaviors showed differences in the attributes of a product, personal values, and the LOHAS characteristics that influenced their purchase intention of eco-friendly products. Findings would enable organizations to understand eco-friendly behavior and to design appropriate strategic decisions to appeal eco-sumers.