• Journal of Environmental Science International
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• v.31 no.12
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• pp.1061-1068
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• 2022

The purpose of this study was to develop a recycling system for ozone off-gas. Although the ozone transmission rate of the injector method differs slightly depending on the ozone injection rate, it reaches approximately 99%, which is very high. During the increase in water inflow to the ozone recycling system from 2 L/min to 10 L/min, the average ozone recycling rate was 99.4% at a 1 ppm ozone injection rate, 98.6% at a 2 ppm ozone injection rate, 98.1% at a 3 ppm ozone injection rate. Ozone treatment facility operating costs can be divided into the costs of pure oxygen production, ozone production, and maintenance. The annual operating costs of ozone treatment facilities in Korea are estimated to be approximately 38.9 billion won. The annual savings are estimated to be approximately 5.8 billion won when the ozone transfer rate of the diffuser method, which is mostly employed in domestic water treatment plants, is 85% and 15% of the ozone is recycled.

• Resources Recycling
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• v.33 no.2
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• pp.46-53
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• 2024

The residual heat and high CaO content present in the slag remaining in the ladle after the completion of continuous casting in the electric arc furnace (EAF) steelmaking process have been utilized to reduce power consumption and lime usage in the ladle furnace (LF) process. However, if the timing of such processes does not align with the LF and continuous casting operations, the recycling rate will decrease. To increase the slag recycling rate, the effect of ladle slag recycling methods, specifically pouring ladle slag into the slag pot in advance for subsequent recycling, on LF operations was analyzed. The slag liquefaction rate was calculated using the thermodynamic program Factsage 8.3 for ladle molten slag recycling methods. By applying each of the 10 heats operations for the ladle slag recycling methods, the desulfurization ability and LF operation performance were compared. It was found that when slag was immediately recycled into the ladle after continuous casting was completed, power consumption decreased by 0.3 MWh, LF operation time was shortened by 1.2 minutes, and the desulfurization rate increased by 5.8%.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.8
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• pp.5-14
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• 2000

The treatment of technical consumer products after using is important for the conservation of our environment. In this paper the demanufacturing technology that is required to maximize the recycling rate of end-of-life products is introduced, The definitions including types of the recycling are described. The factors that have to regard in the design stage of products in order to maximize the recycling rate of the products are introduced. The objective assessment methods for the design for environment are described. Finally disassembly process and future prospect of the automations are discussed.

• Resources Recycling
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• v.9 no.1
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• pp.3-14
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• 2000

In order to prospect current recycling status in Korea, wastes generation and recycling rate were reviewed. Approximately 188,600 ton/day of wastes was generated in 1998; 44,600 ton/day of domestic waste and 144,000 ton/day of industrial waste. During the last five years, waste management laws such as recycling law and environment friendly industry law were prepared. In this article, concerning over waste generation and recycling, the problems and technological developments associated with recycling were summarized.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.1
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• pp.17-26
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• 2017

In order to confirm European packaging waste statistics, this study was investigated annual variability of packaging waste generated, target of recovery and recycling rate for packaging waste and recycling rate of European countries based on Eurostat database. Eurostat is regional society statistics organization designated by European community to distribute development, production and European statistics. From 2005 to 2013, paper and paperboard packaging were generated the largest amount among the total amount of packaging waste generated during the period and the share of main packaging materials were generally constant among the packaging materials. In addition, European Union member countries have established target for the recycling rate and recycling rate for packaging waste which has been well maintained by most EU countries since the 2008 directive was enacted. The recycling rate for whole packaging waste such as glass, paper and paperboard, metal, plastic, wood continues to increase in Europe. In this study, Europe packaging waste statistics were organized and analyzed as yearly transformation of Europe packaging waste occurrence and disposal, recycling rate and recovery rate target value of Europe countries and recycling rate of each country in Europe base on centralized Eurostat database. Moreover GDP reduction were also confirmed due to trend changes and indirect impacts such as economic slump by packaging waste and recycling.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.2
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• pp.130-135
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• 2002

A new Sign algorithm which has improved convergence speed is presented. The data-recycling technique, whose coefficients are multiply adapted in a symbol time period by recycling the received data, is applied to Sign algorithm which has few multiplications. Sign algorithm has very few multiplications and is the most easily implemented, but it gives small rate of convergence relative to others. The proposed algorithm combines the advatage of Sign algorithm, few multiplications, and the virtue of Data-Recycling LMS algorithm, simplicity and fast convergence. The results of computer simulation show that the proposed algorithm has 2 times faster convergence rate than that of LMS algorithm. Comparing to Data-Recycling LMS algorithm, in similar convergence conditions, it requires half fewer multiplications.

• Journal of Dairy Science and Biotechnology
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• v.25 no.1
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• pp.9-13
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• 2007

The present study was carried out to examine the effect of crosslinked ${\beta}$-cyclodextrin(${\beta}$-CD) made by adipic acid on cholesterol removal rate and find the structural change after recycling on SEM observation. The size reduction and morphological changes were found during the recycling process and the profound changes were observed at 8th time reuse. After cholesterol removal in milk, the used crosslinked ${\beta}$-CD was washed for cholesterol dissociation and reused. In recycling study, the cholesterol removal rate at first trial was 92.5% in milk, which was mostly same as that using new crosslinked ${\beta}$-CD(92.4%). With repeated 10th reuse of crosslinked ${\beta}$-CD resulted in 81.4% of cholesterol removal in milk. Similar trend was found in cream and cholesterol removal was 91.5% at 1st trial and 83.4% at 10th trial. In both milk and cream samples, the removal rate at 1st reuse was not significantly different from that at 6th reuse(p>0.05). The present study indicated that crosslinked ${\beta}$-CD made by adipic acid resulted in the effective recycling efficiency, especially up to 6th reuse and morphological modifications were not distinguishable up to 8th reuse.

• Resources Recycling
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• v.12 no.5
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• pp.3-9
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• 2003

In order to prospect current recycling status in Korea, legislative system and policies relating to recycling, wastes generation and recycling rate were reviewed. Approximately 260,400 ton/day of wastes was generated in 2001. 48,400 ton/day of household waste and 212,000 ton/day of industrial waste. During the last ten years, waste management laws such as waste disposal law, recycling law and environment friendly industry law were prepared. In this article, concerning over waste generation and recycling, recycling law, Extended Producer Responsibility System and the problems and technological developments associated with recycling were summarized.

• Resources Recycling
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• v.19 no.6
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• pp.11-26
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• 2010

In order to review the recycling status of urban mine resources in Japan, metal consumption, metal recycling rate and metal recycling industry such as iron scrap, end of life vehiclcs(ELV), waste home appliances and spent IT equipments were surveyed. Japan took rank of top class in the world on the metal consumption and urban mine stock reserve. Metal recycling industries in Japan have been developed through excellent technologies for mineral processing and non-ferrous smelting. On the other hand, the technologies for recycling of rare metals are being developed now. Recycling rate of EL V, waste home appliances and personal computer are higher than the guidelines of the legislative standard.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.1
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• pp.51-57
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• 2016

This study is conducted to find out the problems of the public food waste recycling facility operation and its improvement. In order to save the national budget by analyzing plans to expand including operation rate for the food waste recycling facility, the alternative ways are suggested. The result can be as follows: Policy switch is required not only to save budget and stable disposal of food waste but also to promote resource recycling rather than expanding public facilities. In order to change the policy for stable and eco-friendly disposal of food waste, it is necessary to adopt semipublic system that prevent the decline of the rate of operation of private resource recycling facility. Furthermore, it is required to prepare both qualified technologies of public resource recycling and the ways of profitability secure.