• 콘크리트학회논문집
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• 제17권1호
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• pp.141-147
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• 2005

The development of automobile, vessel, rail road, and machine industry leads an increase of foundry production used as their components, which cause a by-product, waste foundry sand (WFS). The amount of the WFS produced in Korea is over 700,000 tons a year, but most WFS has been buried itself and only $5{\~}6\%$ WFS is recycled as construction materials. Therefore, it is necessary for most WFS to research other ways which can be used in a higher value added product. The study on recycling it as a fine aggregate for concrete or green sand has been in progress in America and Japan since 1970s and 1980s respaectively. In this study, two types of WFS were used as a fine aggregate for concrete. Nine types of concrete aimed at the specified strength of 30 MPa were mixed with washed seashore coarse sand in which salt was removed, and WFS and then appropriate mixture proportion of concrete was determined. Moreover, basic properties such as air contents, setting time, bleeding, workability and slump loss of the fresh concrete with WFS were tested and compared with those of the concrete mixed without WFS. In addition, both compressive strength of hardened concrete at each ages and tensile strength of it at the age of 28 days were measured and discussed.

• 한국기계가공학회지
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• 제17권4호
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• pp.137-142
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• 2018

Recycled synthetic resin materials produced from waste vinyl and waste plastic contain many foreign substances. Plastic products made from this recycled resin materials containing foreign substances are of poor quality, with reduced the strength and rigidity. Foreign substances include heavy metals, cement, foil, dyed paper and dust. In this study, the scratch-Dies process; which remove foreign sbustances, with precision and automation, through a three-stage mesh filter, is designed. The process is evaluated with finite element analysis according to vibration loading and make. After installing the manufactured equipment, recycled resin was producde, and its heavy metal content was evaluated. Recycled synthetic resin materials were also used plastic products and evaluate their strength. In addition, the change in production was assessed.

• Advances in Energy Research
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• 제3권3호
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• pp.167-179
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• 2015

This paper presents a techno-economic analysis of a partial repowering scheme for an existing 210 MW coal fired power plant by integrating a gas turbine and by employing waste heat recovery. In this repowering scheme, one of the four operating coal mills is taken out and a new natural gas fired gas turbine (GT) block is considered to be integrated, whose exhaust is fed to the furnace of the existing boiler. Feedwater heating is proposed through the utilization of waste heat of the boiler exhaust gas. From the thermodynamic analysis it is seen that the proposed repowering scheme helps to increase the plant capacity by about 28% and the overall efficiency by 27%. It also results in 21% reduction in the plant heat rate and 29% reduction in the specific $CO_2$ emissions. The economic analysis reveals that the partial repowering scheme is cost effective resulting in a reduction of the unit cost of electricity (UCOE) by 8.4%. The economic analysis further shows that the UCOE of the repowered plant is lower than that of a new green-field power plant of similar capacity.

• 자원리싸이클링
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• 제16권2호
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• pp.63-76
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• 2007

현재 우리나라 미이용자원의 대표격으로서 전기로 제강분진(EAF Dust)중의 아연(Zn)과 석유탈황폐촉매 중의 몰리브덴(Mo)과 바나듐(V)등을 들 수 있다. 자동차 폐촉매로부터 백금족금속(PGM) 회수 및 폐프린트 회로기판(PCBs)부터의 금, 은, 등도 거론할 수 있으나 유통경로가 복잡하여 정확한 회수통계 파악이 어렵다. 본고에서는 이들 금속의 우리나라에서의 연구동향을 조사 검토하였다. 물질흐름에 관해서는 석유탈황폐촉매에서 회수할 수 있는 Mo, V및 Ni에 한해서만 조사하였다. 그리고 EAF Dust중의 Zn 에 관해서는 후일 별도로 논술하려고 한다. 다만 금속시세가 폭등하고 있기 때문에 금년(2007)내로 Mo및 V의 회수가 확실시되고, 아연도 회수될 전망이다.

• 자원리싸이클링
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• 제27권1호
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• pp.22-30
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• 2018

폐니켈수소전지에 함유되어 있는 유가금속인 니켈, 코발트 그리고 희토류의 산업적 재활용을 위하여 자동차용 폐전지모듈로부터 분해, 분쇄 및 분급을 통하여 전극 분말을 회수하였다. 회수된 전극 분말 스크랩을 황산용액으로 침출한 결과 황산농도 1.0 M, 고액비 25 g/L, 반응 온도 $90^{\circ}C$, 4시간 동안의 반응조건에서 니켈, 코발트 그리고 희토류는 약 99%의 침출결과를 얻었으며, 침출액으로부터 희토류는 10 M NaOH를 이용하여 pH 2.0 이하에서 희토류 침전물과 니켈/코발트 용액 분리가 가능하였다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.279-284
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• 2009

Traditionally, so-called "industrial waste gases", such ad exhaust from boilers at industrial installations and a large quantity of soot discharged from power station, before their release into the atmosphere, have been on occasion subjected to an air cleaning process to remove fine particles that may pollute the atmosphere (such as mist and dust containing various powdery or oily substances and moisture from industrial waste gases). The release of industrial waste gases containing these particles directly into the atmosphere poses a serious threat to the earth environment; and recovery of these noxious substances is required by law in some countries and local governments. in urban areas, air pollution from automobile exhaust and others creates a serious condition. Some homes are equipped with and use indoor air purifiers. In many of the kitchens of restaurants, smoke generated during cooking and otherwise contaminated air are cleansed by air purifiers before being released outside or recycled inside. For the dust collecting devices to recover the fine particles contained in contaminated air, the cause for air pollution and how to purify air, many types based on various principles are known. Specifically, classified based on theories of particle collection, filtration, gravity, inertia, centrifugation, electricity, and cleaning types are cited as available processes. Among them, an appropriate type is selected according to the size or type of fine particles to be collected and conditions for installation. For the efficiency of dust collection, a filtration system (by using bag filters and others) and electric system are particularly outstanding and are therefore used widely in various areas of industry. In this research, rotary type high performance oil mist and smoke collecting system with self auto cleaning device equipped with the cleaning fluid spraying section is investigated.

• 한국가스학회지
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• 제19권2호
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• pp.66-73
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• 2015

가솔린 엔진에서 개조된 가스 엔진에서 발생하는 냉각수와 배기가스를 분석하여 복합발전 시스템에서 활용 가능한 폐열의 양과 질을 확인하였다. 엔진 배기가스의 온도는 $573.8^{\circ}C$이고, 엔진 출구 냉각수의 온도는 $85.7^{\circ}C$이고, 폐열의 양은 엔진 냉각수가 배기가스에 비교하여 두 배 수준이었다. 두 가지 폐열의 상이한 온도와 양에 대응하는 유기랭킨사이클 (Organic Rankine Cycle: ORC) 발전시스템을 설계하고 열역학적 분석을 수행하였다.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.413-419
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• 2005

The United States automotive recycling infrastructure has successfully reduced the amount of automotive waste sent to landfills, especially since the introduction of shredders in the late 1950s. Shredders are necessary to process and recycle automotive hulks and other durable goods. However, this industry faces significant challenges as the automotive manufacturers are increasing the use of nonmetallic components which are difficult to recycle. Additionally, it is becoming obvious that automobiles contain hazardous materials which place heavy burdens on the environment. To address this growing concern, we propose a process planning model for automotive shredders to make tactical decisions regarding at what level to process and at what level to reprocess feed stock materials. The purpose of this paper is to test analytical models to help shredders improve the profitability and efficiency of the bulk recycling processes for end of life automobile returns. The work is motivated by an actual recycling problem that was observed at Capitol City Metals shredding facility in Indianapolis, Indiana.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 2002년도 제54차 추계 학술대회 연제집
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• pp.568-570
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• 2002

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.246-246
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• 2010

In this study, the effect of wast heat-electric energy conversion according to temperature difference between two sides of a thermoelectric module was investigated as a way of electric energy conversion from waste heat generated in machinery system like automobile system.