• Title/Summary/Keyword: Recovering System

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Recovery of high-purity phosphoric acid from the waste acids in semiconductor manufacturing process (반도체(半導體) 제조공정(製造工程)에서 발생하는 혼산폐액(混酸廢液)으로부터 고순도(高純度) 인산회수(燐酸回收))

  • Park, Sung-Kook;Roh, Yu-Mi;Lee, Sang-Gil;Kim, Ju-Yup;Shin, Chang-Hoon;Kim, Jun-Young;Ahn, Jae-Woo
    • Resources Recycling
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    • v.15 no.5 s.73
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    • pp.26-32
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    • 2006
  • The waste solution discharged from the LCD manufacturing process contains acids like nitric, acetic and phosphoric acid and metal ions such as Al, Mo and other impurities. It is important to remove impurities less than 1 ppm in phosphoric acid to reuse as an etchant because the residual impurities even in sub-ppm concentration in semiconductor materials play a major role on the electronic properties. In this study, a mixed system of solvent extraction, diffusion dialysis and ion-exchange was developed to commercialize in an efficient system fur recovering the high-purity phosphoric acid. By vacuum evaporation, almost 99% of nitric and acetic acid was removed. And by solvent extraction method with tri-octyl phosphate (TOP) as an extractant, the removal of acetic and nitric acid from the acid mixture was achieved effectively at the ratio A/O=1/3 with 4th stage of extraction stage. About 97.5% of Al and 36.7% of Mo were removed by diffusion dialysis. Essentially almost complete removal of metal ions and purification of high-purity phosphoric acid could be obtained by using ion exchange.

Recovery of phosphoric acid from the waste acids in semiconductor manufacturing process (반도체 제조공정에서 발생하는 혼산폐액으로부터 고순도 인산 회수)

  • Park, Sung-Kook;Roh, Yu-Mi;Lee, Sang-Gil;Kim, Ju-Yup;Shin, Chang-Hoon;Ahn, Jae-Woo
    • Proceedings of the Korean Institute of Resources Recycling Conference
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    • 2006.05a
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    • pp.90-94
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    • 2006
  • The waste solution discharged from the LCD manufacturing process contains acids like nitric, acetic and phosphoric acid and metal ions such as Al, Mo and other impurities. It is important to removal of impurities to tess than 1ppm in phosphoric acid to reuse as an etchant because the residual impurities even in sub-ppm concentration in semiconductor materials play a major role on the electronic properties. In this study, we have been clearly established that a mixed system of solvent extraction, diffusion dialysis and ion-exchange technique, which made individually the most of characteristics is developed to commercialize in an efficient system for recovering the high-purity phosphoric acid. By applying vacuum evaporation, the yield of the process are almost 99% removal of nitric acid and acetic acid was achieved. And by applying the solvent extraction method with tri-octyl phosphate(TOP) as an extractant, the removal of acetic and nitric acid from the acid mixture was achieved effectively at the ratio O/A=1/3 with four stages and the stripping of nitric acid from organic phase is attained at a ration of O/A=1 with six stages by distilled water. About 97% and 76% removal of Al and Mo were achieved by diffusion dialysis. Essentially complete less than 1ppm removal of Al, Mo by using ion exchange ion resin and purification of the phosphoric acid was obtain.

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Policy Suggestions for Soil Contamination Prevention and Management of Inactive or Abandoned Metal Mines (휴.폐금속광산지역의 토양오염관리정책의 평가)

  • Park Yong-Ha;Seo Kyung-Won
    • Journal of Soil and Groundwater Environment
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    • v.11 no.3
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    • pp.1-11
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    • 2006
  • Attempts were made to analyze the national policy of soil contamination prevention and management of inactive or abandoned metal (IAM) mines in Korea. This approach focused on legal systems and legislation, remediation technology development, and the arrangement or distribution of budgets pertaining to national policy since the mid 1990's. Prevention of Mining Damage and Recovery Act enacted. Defines the roles, responsibility and budget of the government when recovering mine damages. However, in 2005 there still remains to improve the national policy of soil contamination prevention and management of IAM mines. Analysis of national and industrialized foreign countries including the United States, the United Kingdom, and the Netherlands suggest the following improvements: i) arranging distinct regulations between strict and non-strict liability criteria for potentially responsible parties; limiting innocent and non-strict liability depending on the period of incurred mining activity, ii) enhancing participation of local communities by enforcing law and legislation, iii) establishing a national database system of (potentially) IAM contaminated sites based on the Website-Geographic Information System, iv) carrying out site-specific risk assessments and remediation of IAM contaminated sites, v) preparation and distribution of clean-up fund at mine sites adequately, and vi) technology development for the cleaning of IAM contaminated sites; awarding positive incentives of a legal nature for participants applying newly developed technology in IAM mines.

Eco-friendliness Evaluation of a Low-Noise and Dust-Recovery Type Pavement Cutter (저소음·분진회수형 도로절단기의 친환경성 평가)

  • Kim, Kyoon Tai
    • Ecology and Resilient Infrastructure
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    • v.8 no.4
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    • pp.194-203
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    • 2021
  • With the recent increase in maintenance works on water and sewer pipes as well as district heating supply pipes, pavement cutting work using pavement cutter is on the rise. The pavement cutting operation generates considerable dust (cutting sludge) as well as noise; therefore, it is necessary to apply eco-friendly technologies that have low noise and dust recovery capability. Thus far, various equipment for recovering dust have been developed; however, there is a limitation in that the environmental friendliness is not quantified. Therefore, in this study, we developed a low-noise, dust-recovery type pavement cutter that can fundamentally remove the causes of environmental hazards such as noise and dust and evaluated the eco-friendliness of the pavement cutting process performed by this cutter. To this end, an integrated water cooling-sludge recovery system composed of a vacuum device and a sludge suction unit was developed, and the developed system was applied to a pavement cutter. Subsequently, the developed equipment was applied to the test bed, and data related to its eco-friendliness were collected and evaluated. The results showed that the cutting sludge recovery rate of the developed equipment was greater than 83%, the noise level was approximately 82 - 83 dB, and the sound power level was 115 dB. The results of this study will be used as basic data to develop improved pavement cutters in the future with improved cutting sludge recovery performance and lower noise.

A Study on the Citizen Advocates' Perception of Their Role for People with Developmental Disabilities (시민옹호인의 역할인식에 관한 연구 - 발달장애인 옹호경험을 중심으로 -)

  • Jeon, Ji-Hye;Lee, Se-Hee
    • Journal of Convergence for Information Technology
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    • v.9 no.3
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    • pp.112-119
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    • 2019
  • This study examined the role of citizen advocates in advocating for people with developmental disabilities. Citizen advocacy refers to activities that advocate and represent citizens on behalf of those who are socially vulnerable. The purpose of this study is to analyze the role concept of citizen advocates by conducting focus group interviews and dividing the 13 citizen advocates with developmental disabilities into 4 groups. It is divided into four main subjects and nine sub-themes. The main theme are 'Self-transformation of the parties', 'Restoring the rights of the parties', 'Being with the parties', and 'Expanding the world of the parties'. Sub-themes are 'Recognizing and solving the problem of self', 'Granting role to speak', 'Recovering the initiative of service use', 'Restoring the rights of existing (family and neighbor), "Preventing money harm" "Speaking instead", "Encouraging and petting people", "Promoting change in the community", and "Expanding the size of the world a little bit". Based on this, we discussed the importance of citizen advocacy as a preventive advocacy system, the relationship between citizen advocacy and professional advocacy system, the difference between volunteer and personal assistants and citizen advocacy, and considerations for citizen advocacy.

Fifty Years of Scientific Ocean Drilling (1968-2018): Achievements and Future Direction of K-IODP (해양 과학시추 50년 (1968-2018): 한국의 성과 및 미래 방향)

  • KIM, GIL YOUNG
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.24 no.1
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    • pp.30-48
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    • 2019
  • The year 2018 is the $50^{th}$ anniversary of scientific ocean drilling. Nevertheless, we know more about the surface of the moon than the Earth's ocean floor. In other words, there are still no much informations about the Earth interior. Much of what we do know has come from the scientific ocean drilling, providing the systematic collection of core samples from the deep seabed. This revolutionary process began 50 years ago, when the drilling vessel Glomar Challenger sailed into the Gulf of Mexico on August 11, 1968 on the first expedition of the federally funded Deep Sea Drilling Project (DSDP). DSDP followed successively by Ocean Drilling Program (ODP), Integrated Ocean Drilling Program (old IODP), and International Ocean Discovery Program (new IODP). Concerning on the results of scientific ocean drilling, there are two technological innovations and various scientific research results. The one is a dynamic positioning system, enables the drilling vessel to stay fixed in place while drilling and recovering cores in the deep water. Another is the finding of re-entry cone to replace drill bit during the drilling. In addition to technological innovation, there are important scientific results such as confirmation of plate tectonics, reconstruction of earth's history, and finding of life within sediments. New IODP has begun in October, 2013 and will continue till 2023. IODP member countries are preparing for the IODP science plan beyond 2023 and future 50 years of scientific ocean drilling. We as IODP member also need to participate in keeping with the international trend.

Research on status and characteristics of wastewater discharger cost in Local Government (국내 기초자치단체 하수도 원인자부담금 현황 및 특성 분석 연구)

  • Jiyeol Im;Dong Hyun Lee;Kyungik Gil
    • Journal of Wetlands Research
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    • v.25 no.4
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    • pp.230-236
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    • 2023
  • The sewage system was continuously distributed as a concept of public service and protection for water system such as wet-land, resulting in deterioration of the management of sewage management institutions. Accordingly, under the leadership of the central government, various sewage policies are being promoted to streamline the management of sewage management institutions. The main points were related to costs, and typical characteristics include wastewater cost and wastewater discharger cost. In this research, the current status and characteristics of the wastewater discharger cost of 71 local governments in Korea were analyzed. As a result, 41 places (57%) were found to be less than 1,000,000 won/m3 to 2,000,000 won/m3, with an average was 1,990,653 won/m3 (median was 1,918,000 won/m3). In addition, the rate of wastewater discharger cost was increased when the wastewater discharger cost was higher stage. The influential parameters of local governments, which were relatively correlated with the wastewater discharger cost, were analyzed as the rate of recovering wastewater cost and financial independence rate. The results of this research could be used as basic data for wastewater discharger cost, and future researches are needed on how to calculate the appropriate level of wastewater discharger cost.

Land Law Meaning of the Land Development Permission System (토지개발허가제의 토지법적 의의 -「국토계획법」 제56조를 중심으로-)

  • Lee, Sun-Young;Kim, Sang-Jin
    • Korea Real Estate Review
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    • v.24 no.1
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    • pp.77-90
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    • 2014
  • With the purpose of preventing improper development on the national land, the land development permission system which is performed from 2002 has meaning as a type of limiting the property right, but modification on the details of traditionally understood land ownership is inevitable. Also, releasing the development prohibit on the land not only stop in recovering the freedom for land development, but also can be interpretated as a cause of forming the land development right, therefore the purpose of this study is to develop this into a real right. When we look at the development activity permission as a form of limiting the property right, constitutional problems of basis for that limit and compensation demand can occur. However, that limit can be recovered or relieved through permitting the development activity, therefore the compensation problem can be solved. Due to the development activity permission system, the land development right was separated from the land ownership to be communalized, and now, the land ownership only has condition use right left and don't have the future condition change right in principle, therefore modifying the traditional concept of land ownership is inevitable. By the virtue of the land ownership authority, the land development permission system must have the property to separate the development right as the independent right to be authorized of its legitimacy. Without these properties, the land development permission system cannot satisfy the social necessity of the land development right and its discussion under the category of the land ownership limit theory can't be deviated. In the existing "Civil Law" or in the Land Regulation Law system, there are many difficulties and limits in generalizing the land development right as a real right. Therefore, it is considered that by establishing a social law idea of Framework Act on the Land to characterize the land right theory in the real right theory, the land development permission system or the development right theory should be studied and developed independently and systematically.

A Study on the Large-Scale Power Blackout Management System in the Level of National Crisis Management (대규모 정전상태에 대비한 국가위기관리 방향에 관한 연구)

  • Cho, Kwang-Rae;Joo, Il-Yeob
    • Korean Security Journal
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    • no.10
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    • pp.387-407
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    • 2005
  • Thanks to the developments of IT technologies, such critical infrastructures as fundamental structures of energies, material circulations, monetary circulations, and living necessaries are intertwined as well as mutually dependent. In this respect, the fact that national infrastructures are closely related to IT infrastructures implies not only expected benefits to provide diverse information-based services, but also anticipated costs to bring about new dangers. However, in spite of these threats, traditional researchers have not put enough interests in these indirect danger, which yield the damages in broad areas through paralyzing risk management systems, although they have investigated such direct threats as nuclear accidents, conflagrations, traffic troubles, and gasoline accidents. Considering that the tendency to depend on electricity, so-called electrification, which is caused by automation and informationalization, is intensified in all parts of society, the breakout problem as a factor to inhibit securities in information-oriented society is significant. Thus, the problems of large-scale power blackout should be treated as national crises. Also, preparation systems for large-scale power blackout have to be provided quickly. In this paper, with analyzing various cases of large-scale power blackout and investigation the causes of them, researches on the blackout management systems of Korea are to be present, on the basis of national crisis management states which are comprised of protection (mitigating and preparing), responding, and recovering(rewarding).

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The Grounded Theoretical Study on Negative Emotion Recovery Process of Female College Students Through Bibliotherapy (독서치료를 통한 여대생의 부정적 정서 회복과정에 대한 근거이론적 연구)

  • Kim, Kil-Ja
    • Journal of the Korean Society for Library and Information Science
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    • v.42 no.3
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    • pp.103-131
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    • 2008
  • Today. the mental health has a great deal of impact on individuals and the society surrounding. Therefore. this research is to propose a way of bibliotherapical intercession by stages and patterns as to examine the recovery process of students with negative emotion by using the grounded theoretical method. This research collected materials through focus-interview, participant observation and book reports of 4 experiments involving female college students aged from 21 to 23, all having emotional and psychological difficulties. The recovery process of female students with negative emotion involved causal factors such as "recognition of hidden wound" "Sense of inferiority", and "difficulty in forming relationships", as well as contextual factors like "sympathetic attitude". which altogether brought about the core phenomenon. "pursuit for healthy ego". This core phenomenon induced to recovering the bright and positive attitude through using the strategies of 'self insight' and application of 'management plan', influence by such incoherent conditions as 'intimate surroundings' and $\setminus$ 'support system patterns'. And as time passed. the recovery process appeared tin four stages: 'issues recognition'. 'emotional responses', 'issue solution' and 'self application'.