• 제목/요약/키워드: Resource recovery

검색결과 388건 처리시간 0.026초

해수(海水)로부터 희유금속(稀有金屬) 회수(回收) 연구동향(硏究動向) (R&D Trends of Rare Metals Recovery from Seawater)

  • 김종헌;노경란;김상우;최성배;길상철
    • 자원리싸이클링
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    • 제22권6호
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    • pp.73-80
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    • 2013
  • 해양광물자원은 크게 해저면에 부존되어 있는 해저광물자원과 해수 중에 녹아 있는 해수광물자원으로 대별된다. 해수에는 막대한 양의 유용광물이 녹아 있어 회수기술 개발이 완료되면 상업화 가능성이 큰 것으로 알려져 있다. 21세기에 들어 육상금속자원의 저품위화 및 매장량 고갈에 따라 자원 보유국들이 자원을 무기화 하는 경향이 심화되고 있다. 따라서 대부분의 금속자원을 수입에 의존하는 우리나라는 삼면이 바다인 지리적 특성을 살려 해수로부터 희유금속 회수기술 개발에 적극적으로 나설 필요가 있다. 본 연구에서 해수로부터 희유금속 회수관련 논문분석 결과, 미국이 495편의 논문을 게재하여 양적 질적으로 가장 우수한 것으로 나타났다. 연구기관별로 보면 Chinese Acad. Sci.가 152편의 논문을 게재하여 양적으로 많은 연구가 이루어졌으며, 31편의 논문을 게재한 Univ. Oxford는 질적으로 가장 우수한 것으로 나타났다.

Mg/Al Impregnated Biochar for the Removal and Recovery of Phosphates and Nitrate

  • Kim, Dong-Jin
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2019년도 정기학술대회 발표논문집
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    • pp.134-134
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    • 2019
  • Utilization of organic waste as a renewable energy source is promising for sustainability and mitigation of climate change. Pyrolysis converts organic waste to gas, oil, and biochar by incomplete biomass combustion. Biochar is widely used as a soil conditioner and adsorbent. Biochar adsorbs/desorbs metals and ions depending on the soil environment and condition to act as a nutrient buffer in soils. Biochar is also regarded as a carbon storage by fixation of organic carbon. Phosphorus (P) and nitrogen (N) are strictly controlled in many wastewater treatment plants because it causes eutrophication in water bodies. P and N is removed by biological and chemical methods in wastewater treatment plants and transferred to sludge for disposal. On the other hand, P is an irreplaceable essential element for all living organisms and its resource (phosphate rock) is estimated about 100 years of economical mining. Therefore, P and N recovery from waste and wastewater is a critical issue for sustainable human society. For the purpose, intensive researches have been carried out to remove and recover P and N from waste and wastewater. Previous studies have shown that biochars can adsorb and desorbed phosphates implying that biochars could be a complementary fertilizer. However, most of the conventional biochar have limited capacity to adsorb phosphates and nitrate. Recent studies have focused on biochar impregnated with metal salts to improve phosphates and nitrate adsorption by synthesizing biochars with novel structures and surface properties. Metal salts and metal oxides have been used for the surface modification of biochars. If P removal is the only concern, P adsorption kinetics and capacity are the only important factors. If both of P and N removal and the application of recovery are concerned, however, P and N desorption characteristics and bioavailability are also critical factors to be considered. Most of the researches on impregnated biochars have focused on P removal efficiency and kinetics. In this study, coffee waste is thermally treated to produce biochar and it was impregnated with Mg/Al to enhance phosphates and nitrate adsorption/desorption and P bioavailability to increase its value as a fertilizer. Kinetics of phosphates and nitrate adsorption/desorption and bioavailability analysis were carried out to estimate its potential as a P and N removal adsorbent in wasewater and a fertilizer in soil.

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정신장애인 회복에 초점을 둔 당사자 리더십 프로그램 개발 연구 (Development of Peer-Leadership Program focused on Recovery of People with Mental Illness)

  • 김민;이근희
    • 한국산학기술학회논문지
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    • 제21권6호
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    • pp.256-265
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    • 2020
  • 본 연구는 정신장애인 회복을 위한 당사자 리더십 프로그램을 개발하고 그 효과성을 탐색하는 것이 목적이다. 프로그램 개발을 위해 문헌검토와 선행프로그램 분석을 실시하였으며, 정신장애에 대한 이해-셀프리더십-역량강화-자기 주도 실천계획을 포함하는 Brown의 회복 프레임워크를 적용하였다. 이러한 과정을 통해 당사자주도 활동, 장애의 이해와 인식개선 활동, 당사자 실천계획개발 등을 주제로 2박 3일 동안 총 6회기 프로그램을 개발하였다. 본 프로그램은 회복의 가치를 기반으로 당사자 스스로 할 수 있다는 역량강화를 위해 교육-이해-계획-실행의 단계로 구성하였다. 개발된 프로그램은 정신재활시설 이용자 20명을 대상으로 실시하였다. 프로그램 참여 후 변화를 측정하기 위해 낙인, 역량강화, 셀프리더십, 장애수용 척도를 이용하여 비교분석하였다. 분석결과 참여자들의 낙인(p < .05), 역량강화(p < .05), 셀프리더십(p < .01), 장애수용(p < .05)에서 통계적으로 유의미한 변화가 있는 것으로 나타났다. 이러한 결과는 개발된 당사자 리더십 프로그램이 정신장애에 대한 이해 증가, 역량강화, 리더십 능력향상을 포함하는 회복 프로그램임을 시사한다. 연구결과를 기반으로 향후 당사자 리더십 프로그램의 확대를 위한 논의와 제언을 하였다.

Providing survivability for virtual networks against substrate network failure

  • Wang, Ying;Chen, Qingyun;Li, Wenjing;Qiu, Xuesong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권9호
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    • pp.4023-4043
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    • 2016
  • Network virtualization has been regarded as a core attribute of the Future Internet. In a network virtualization environment (NVE), multiple heterogeneous virtual networks can coexist on a shared substrate network. Thus, a substrate network failure may affect multiple virtual networks. In this case, it is increasingly critical to provide survivability for the virtual networks against the substrate network failures. Previous research focused on mechanisms that ensure the resilience of the virtual network. However, the resource efficiency is still important to make the mapping scheme practical. In this paper, we study the survivable virtual network embedding mechanisms against substrate link and node failure from the perspective of improving the resource efficiency. For substrate link survivability, we propose a load-balancing and re-configuration strategy to improve the acceptance ratio and bandwidth utilization ratio. For substrate node survivability, we develop a minimum cost heuristic based on a divided network model and a backup resource cost model, which can both satisfy the location constraints of virtual node and increase the sharing degree of the backup resources. Simulations are conducted to evaluate the performance of the solutions. The proposed load balancing and re-configuration strategy for substrate link survivability outperforms other approaches in terms of acceptance ratio and bandwidth utilization ratio. And the proposed minimum cost heuristic for substrate node survivability gets a good performance in term of acceptance ratio.

Developments and Trends in Fisheries Processing: Value-Added Product Development and Total Resource Utilization

  • Meyers Samuel P.
    • 한국수산과학회지
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    • 제27권6호
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    • pp.839-846
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    • 1994
  • Changing concepts in fishery science increasingly are recognizing depletion of traditional stocks, utilization of alternate(non-traditional) species, demand for high quality products, and a total resource utilization approach. Innovative practices are occurring in fisheries processing wherein solid and liquid discharges are no longer treated as 'waste,' but rather as valuable feedstocks for recovery of a variety of value-added ('value enhanced') by-products. Among these are protein hydrolysates, soluble proteins and amino acids, proteolytic enzymes, flavor and flavor extracts, pigments, and biopolymers such as chitosan. Properties and applications of this deacetylated derivative of chitin are noted. Crustacean processing by-products are discussed in terms of their serving as materials for generation of natural flavors and flavor extracts, and products such as fish sauces using contemporary enzymatic techniques. Various food and feed applications of fisheries processing by-products are illustrated with increased usage seen in formulated diets for an expanding aquaculture market. Examples are given of aquaculture becoming increasingly significant in global fisheries resource projections. Critical issues in the international seafood industry Include those of seafood quality, processing quality assurance (HACCP), and recognition of the nutritional and health-related properties of fisheries products. A variety of current seafood processing research is discussed, including that of alternate fish species for surimi manufacture and formulation of value-added seafood products from crawfish and blue crab processing operations. Increasing emphasis is being placed on international aspects of global fisheries and the role of aquaculture in such considerations. Coupled with the need for the aquatic food industry to develop innovative seafood products for the 21st century is that of total resource utilization. Contemporary approaches in seafood processing recognize the need to discard the traditional concept of processing 'waste' and adapt a more realistic, and economically sound, approach of usable by-products for food and feed application. For example, in a period of declining natural fishery resources it is no longer feasible to discard fish frames following fillet removal when a significant amount of residual valuable flesh is present that can be readily recovered and properly utilized in a variety of mince-based formulated seafood products.

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폐 초내열합금 염산침출 용액으로부터 Alamine304-1을 이용한 레늄의 용매추출분리 (Solvent Extraction Separation of Re (VI) from Hydrochloric Acid Leaching Solution of Spent Super Alloy by Alamine 304-1)

  • 안종관;정희경;장재용;김민석
    • 자원리싸이클링
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    • 제24권5호
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    • pp.56-62
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    • 2015
  • 폐 초내열합금으로부터 침출된 염산용액에서 레늄을 회수하기 위하여 용매추출법을 이용한 레늄의 분리연구를 수행하였다. 용매추출공정을 통해 수상은 레늄이 용해된 합성용액을 사용하고 추출제의 종류 및 농도, 수상의 pH, HCl의 농도, 불순물의 영향을 조사하는 연구를 진행하였다. 레늄의 원료로 Ammonium perrhenate ((APR), Aldrich, $NH_4ReO_4$)을 사용하였고, 수상에 존재하는 레늄을 유기상으로 추출하기 위해 추출제는 음이온추출제인 Alamine304-1, 양이온추출제인 Cyanex272과 $D_2EHPA$를 사용하였다. 음이온추출제인 Alamine304-1 사용시 레늄의 추출율이 99% 이상 나타났으며 수상의 pH 는 0-2 사이에서 99% 추출되었다. Alamine304-1의 농도를 0.1, 0.5, 1 및 2%으로 조절하여 추출실험한 결과, 농도가 증가함에 따라 추출율이 증가한다. 레늄용액에 알루미늄, 코발트, 바나듐을 첨가하여 용매추출법에 의해 분리 실험한 결과 레늄은 99.8 %으로 추출되었으나 기타 금속들은 거의 추출되지 않았다.

막증류 공정의 전처리 공정으로서 천연 제올라이트 컬럼 적용 (Scalants removal from synthetic RO brine using natural zeolite)

  • 정성필;정하윤;윤택근;이석헌
    • 상하수도학회지
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    • 제30권3호
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    • pp.279-284
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    • 2016
  • Membrane distillation (MD) is the thermally driven water separation process based on the vapor pressure difference across the membrane. In order to increase the water recovery of the conventional RO process, the additional MD-PRO pocess was suggested. In this study, the syntheric RO brine was used as a feed solution of the MD process. Due to the high salinity of the RO brine, the MD membrane could be fouled by the scalants. In order to mitigate the scaling on the MD membrane surface, the pre-treatment process using the column filled by natural zeolite was applied. The roughing filter was installed between the pre-treatment process and MD system in order to prevent possible particulate fouling by the debries of the natural zeolite. Moreover, in order to enhance the CEC of the natural zeolite, the NaCl soaking was conducted. The flux and electronic conductivity were monitored under given experimental conditions. And the membrane morphology and the chemical compositions were analyzed by using the SEM-EDX.

남북경제협력에 따른 개발이익 경매와 DMZ 보전기금 확보 (A Study on Auction Mechanism for DMZ Conservation using the South-North Korean Economic Development Projects)

  • 박호정;김준순;김현희
    • 자원ㆍ환경경제연구
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    • 제28권1호
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    • pp.39-59
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    • 2019
  • DMZ는 반세기 이상 인위적 활동이 배제되어 우수한 생태계를 보유하고 있다. 통일 이후에도 DMZ의 생태계는 보전되어야 하며 이를 위해서는 남북한 통일 이후가 아니라 사전에 그 보전방안이 마련되어야 한다. DMZ 생태자원 보전에는 생태자원 관리 비용 뿐만 아니라 복구비용 및 연구예산까지 수반되어야 하므로 상당한 규모의 예산이 필요하다. 이에 본 논문은 실물옵션과 경매이론을 연계하여 경제적 인센티브 메커니즘을 이용한 DMZ 보전기금 확보 방안을 연구하고자 한다. 다수의 사업자들은 경매를 통해 북한지역 개발사업권을 획득하려고 하고, 매몰비용에 대한 사적 정보를 가지고 있으며, 사업수익의 일부를 보전기금으로 지불한다고 할 때, 먼저, 경매 참가자의 최적 투자시기를 결정하는 실물옵션 모형을 분석하고, 다음으로 베이즈 내쉬균형을 이용해 경매 참가자가 사적 정보에 대해 진실을 보고할 경매를 설계한다.

Designing Dataset for Artificial Intelligence Learning for Cold Sea Fish Farming

  • Sung-Hyun KIM;Seongtak OH;Sangwon LEE
    • International journal of advanced smart convergence
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    • 제12권4호
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    • pp.208-216
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    • 2023
  • The purpose of our study is to design datasets for Artificial Intelligence learning for cold sea fish farming. Salmon is considered one of the most popular fish species among men and women of all ages, but most supplies depend on imports. Recently, salmon farming, which is rapidly emerging as a specialized industry in Gangwon-do, has attracted attention. Therefore, in order to successfully develop salmon farming, the need to systematically build data related to salmon and salmon farming and use it to develop aquaculture techniques is raised. Meanwhile, the catch of pollack continues to decrease. Efforts should be made to improve the major factors affecting pollack survival based on data, as well as increasing the discharge volume for resource recovery. To this end, it is necessary to systematically collect and analyze data related to pollack catch and ecology to prepare a sustainable resource management strategy. Image data was obtained using CCTV and underwater cameras to establish an intelligent aquaculture strategy for salmon and pollock, which are considered representative fish species in Gangwon-do. Using these data, we built learning data suitable for AI analysis and prediction. Such data construction can be used to develop models for predicting the growth of salmon and pollack, and to develop algorithms for AI services that can predict water temperature, one of the key variables that determine the survival rate of pollack. This in turn will enable intelligent aquaculture and resource management taking into account the ecological characteristics of fish species. These studies look forward to achievements on an important level for sustainable fisheries and fisheries resource management.

주공정에서 아질산화-혐기성 암모늄 산화법에 의한 단축질소제거공정 연구동향 (Main-stream Partial Nitritation - Anammox (PN/A) Processes for Energy-efficient Short-cut Nitrogen Removal)

  • 박홍근;유대환
    • 한국물환경학회지
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    • 제34권1호
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    • pp.96-108
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    • 2018
  • Large efforts have recently been made on research and development of sustainable and energy-efficient short-cut nitrogen removal processes owing to strong attention to the energy neutral/positive wastewater treatment system. Anaerobic ammonium oxidizing bacteria (anammox bacteria) have been highlighted since 1990's due to their unique advantages including 60% less energy consumption, nearly 100% reduction for carbon source requirement, and 80% less sludge production. Side-stream short-cut nitrogen removal using anammox bacteria and partial nitritation anammox (PN/A) has been well established, whereas substantial challenges remain to be addressed mainly due to undesired main-stream conditions for anammox bacteria. These include low temperature, low concentrations of ammonia, nitrite, free ammonia, free nitrous acid or a combination of those. In addition, an anammox side-stream nitrogen management is insufficient to reduce overall energy consumption for energy-neutral or energy positive water resource recovery facility (WRRF) and at the same time to comply with nitrogen discharge regulation. This implies the development of the successful main-stream anammox based technology will accelerate a conversion of current wastewater treatment plants to sustainable water and energy recovery facility. This study discusses the status of the research, key mechanisms & interactions of the protagonists in the main-stream PN/A, and control parameters and major challenges in process development.