• 제목/요약/키워드: dust

검색결과 3,963건 처리시간 0.028초

The Effect of Chemical Admixtures on Removal of Scattered Dust

  • Son, Ho Jeong;An, Jung Min;Chung, Chul-Woo;Lee, Jae-Yong
    • 한국건축시공학회지
    • /
    • 제13권6호
    • /
    • pp.594-601
    • /
    • 2013
  • One of the important problems associated with building demolition is the dust generated during the work. The only way to reduce the demolition dust is to use a dust net during water spraying. However, it is difficult to supply the necessary amount of water to remove demolition dust, thus making it difficult to apply this method on a demolition site. This work attempted to find an alternative approach to dust removal by incorporating surfactant and high range AE water reducer in the water being sprayed. Through the experiment, it was found that the addition of surfactant did not contribute to the removal of demolition dust. However, the use of high range AE water reducer showed better performance than spraying plain water, indicating that some amount of demolition dust had been adsorbed on the high range AE water reducer.

RECOVERY OF METALS FROM EAF DUST WITH RAPID SYSTEM

  • Shin, Hyoung-ky;Moon, Seok-min;Jhung, Sung-sil
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
    • /
    • pp.381-386
    • /
    • 2001
  • The dust generated from the electric arc furnace steel making process is classified as hazardous material by Korean Environmental Protection Acts, mainly because of the existence of water teachable Pb, Zn and Cd. Thus the treatment of EAF dust is being carried out to fulfill both the environmental aspect and recovery of valuable metals. To establish the proper process for recovering the valuable metals (Fe, Zn, Pb and Cd) and producing the non-toxic slag from EAF dust, using RAPID-10 system, feasibility study have been carried out. To find out the scale-up factor for designing the commercial scale EAF dust treatment process(capacity 50,000 ton EAF dust per year) entitled RAPID-50 system. The design and construction of RAPID-50 (RIST Arc Plasma Industrial Device) system for treating 50,000 ton of EAF dust per year is now undergoing. Overall plan for treating EAF dust generated in KOREA will be setup after successful operation (December, 2002) of RAPID-50 system.

  • PDF

동북아 황사문제에 대한 일반인의 인식 (The Recognition for Asian-dust in North-East Asia)

  • 정창훈
    • 한국환경과학회지
    • /
    • 제13권12호
    • /
    • pp.1145-1150
    • /
    • 2004
  • Dust phenomenon is a critical thing in the East Asian countries. However, it is quite recent that Asian dust has drawn much attention and the scientific investigation of dust particles began. In this study, the recognition for Asian-dust in Northeast Asia region was analyzed. The survey results show that the people generally recognize the origins and seriousness of Asian dust and understand the difficulty in solving the dust related problems. However, approaches to figure out Asian dust have many difficulties and limits in scientific, economic and political points of view and more detailed road map is needed based on government policy.

먼지 피해의 환경분쟁조정 사례 분석과 배상액 산정안 제언 (Dispute Mediation Cases and Suggestions for Calculating Compensation for Dust Damage)

  • 박정호
    • 한국환경과학회지
    • /
    • 제32권10호
    • /
    • pp.693-701
    • /
    • 2023
  • In this study, we analyzed 82 dust damage dispute mediation cases over the past 5 years and evaluated cases where the probability of damage was verified through dust concentration measurement, modeling prediction, and chemical composition analysis. The cause of dust damage was a construction site, which accounted for most of the damage (97%), and was closely related to the distance from the construction site, total floor area of the construction site, and construction duration. Compensation was decided in only 33% of dust damage cases, and in only 6% (five cases) were damages determined using scientific techniques such as dust measurement, and forecasting. The main criteria for determining compensation were whether administrative measures were taken and evidence of damage in the form of videos and photos. In the future, measuring or model for the amount of dust damage is necessary to determine whether the limit has been exceeded and to revise the standard for calculating compensation through various lines of evidence of dust damage.

실내 공간별 미세먼지농도 비교 데이터의 시각화 (Visualization of the Comparison between Airborne Dust Concentration Data of Indoor Rooms on a Building Model)

  • 이상익;이진국
    • 한국주거학회논문집
    • /
    • 제26권4호
    • /
    • pp.55-62
    • /
    • 2015
  • The international concern on the inhalable fine dust is continuing to increase. In addition to the toxic properties of the fine dust itself, it can be more dangerous than other environmental factors since the dust pollution is hard to be detected by human sense. Although the information on outdoor air condition can be acquired easily, the indoor dust concentration is another problem because the indoor air condition is influenced by the architectural environment and human activity. It means occupants may be exposed to indoor dust pollution over a long period without being aware. Therefore the indoor dust concentration should be measured separately and visualized as an intuitive information. By visualizing, the indoor dust concentration in each space can be recognized practically in compare with the degree of pollution in adjacent spaces. Besides the visualization outcome can be used as base data for related research such as an analysis of the relation between indoor dust concentration and architectural environment. Meanwhile, with the development of network and micro sensing devices, it became possible to collect wide range of indoor environment data. In this regards, this paper suggests a system for visualization of indoor dust concentration and demonstrates it on an actual space.

황사 이동 경로에 따른 대기 부유 곰팡이 포자의 변화 (Variations of Airborne Fungal Spore Composition due to the Asian Dust Trajectories)

  • 김종호;여환구
    • 한국대기환경학회지
    • /
    • 제20권1호
    • /
    • pp.69-76
    • /
    • 2004
  • Asian Dust samples were collected in the ambient air of Seosan, Western Korea, in spring of 2000∼2002. PM (Particulate Matter) concentrations were 199,8$\mu\textrm{g}$/㎥ in the first Asian Dust period (March, 23∼24) and 249.4$\mu\textrm{g}$/㎥ in the second period (April, 7∼9) of 2000. Compared with the concentrations in 2000, relatively low PM concentrations, 157.3$\mu\textrm{g}$/㎥ were measured in the periods of 2001 (April, 24∼26). Especially high PM concentration 953.1$\mu\textrm{g}$/㎥ were measured in the periods of 2002 (March, 21∼22). The variation in the PM concentration was observed according to the time for the formation of Asian dust. Considering the particle size distributions of Asian dust, a high concentration was also observed in coarse particle region. The results of backward trajectory model showed the route of the dust storms from northern area of Mongol and Gobi desert. Various mycelia grown from fungal spores were observed on the PM samples and identified at the genus level. All the genera from the three years (2000∼2002), Fusarium, Aspergillus, Penicillium, Basipetospora, Epicoccum and Monotospora are hyphomycetes in the division Fungi imperfecti (Deuteromycota). Fungal composition on the dust sample in March, 2000 was similar to the result of March, 2002. However, the result of April, 2001 was obviously different from the other dust periods. The variations of fungal compositions between the dust periods could be caused by the trajectories of the dust storms.

활성탄으로 코팅된 전극에서 분진의 제거 (Removal of Dust in Positive and Negative Plates of Electrode Coated with Activated Carbon)

  • 김광수;박현철;전태환;이주행;남상철
    • 한국대기환경학회지
    • /
    • 제29권6호
    • /
    • pp.830-837
    • /
    • 2013
  • The purposes of this research are to know the dust removal efficiency according to the changes of gab between positive and negative plates in dust removal chamber. The experiments for dust removal efficiencies were conducted with changing the electrode-plate gab from 2 cm to 1 cm while the electric pressure, influent flow, and linear velocity were kept 5 kV, 80 L/min, and 6 cm/sec, respectively. From the experimental results of the electrode-plate gab of 2 cm, dust removal efficiencies were decreased to as low as about 50%. Attached dust on the surface of electrodes was released due to a reverse electric charge of dust. From the experimental results of the electrode-plate gab of 1 cm, dust removal efficiencies were increased to as high as about 80% due to the dust attachment velocity to the electrodes to be far more fast than influent linear velocity. Finally, to protect a attached dust from occurring a reverse electric charge it is needed to install the non-conductor between positive and negative electrodes and also to remove air humidity.

자동차 섀시 시스템에 유입되는 먼지입자에 의한 고무-시일 부품의 마멸특성 PART I : 자동차 섀시 시스템에 유입되는 먼지입자분석 (Wear Characteristics of Rubber-Seal for Inflow of Dust Particle in Automobile Chassis System PART I : Analysis of Dust Particle for Inflow in Automobile Chassis System)

  • 이영제;정순오;원태영;김기훈;김대성
    • Tribology and Lubricants
    • /
    • 제25권2호
    • /
    • pp.120-124
    • /
    • 2009
  • In automobile chassis system, several environmental factors weaken durability of automobile's components. The environmental factors are temperature, humidity, intensity of radiation and dust particle inflow. Especially, dust particle inflow leads to increase in friction and wear of automobile's components. The wear of automobile's component leads to increase in noise and exerts a bad influence on life of components. In this study, dust particles were investigated for study on the influence of dust particle inflow. Dust particles are collected on urban area, rural area and highway in China. The size of dust particle is analyzed using the image plus program, and the element of dust particle is analyzed using the SEM and EDX. The elements of dust particle are $SiO_2$ and $Al_{2}O_{3}$. The other elements(Na, Ca, Cl etc..) are detected on urban area and highway.

노천광산의 발파분진 비산영역 예측에 관한 연구 (Study on Simulation of Dust Diffusion at Open Pit Mines)

  • 김복윤;이상권;조영도;김임호
    • 터널과지하공간
    • /
    • 제8권3호
    • /
    • pp.194-199
    • /
    • 1998
  • 본 연구는 석회석 노천채광장의 발파 분진이 주변을 통과하는 특고압 선로에 어느정도 비산 퇴적할 것인지, 어떤 문제를 일으킬 것인지를 평가하기 위한 연구였다. 발파 현장이 분진 발생량 및 입도분포는 그간의 연구 실적도 있고 계측도 가능하지만 얼마만큼의 분진이 어느 정도 거리까지 비산 퇴적할 것인지를 예측하기란 매우 어려운 일이다. 따라서 본 연구에서는 최근 개발한 바 있는 수치유체역학(CFD)을 이용한 3차원 유체거동 해석 프로그램(3D-Flow)을 이용하여 송전선로에 미치는 영향을 예측하는 시도를 하였다. 지형조건, 기상조건에 따른 시뮬레이션을 통하여 석회석 분진은 송전선로에 큰 영향을 미치지 않을 것으로 판단 되었다.

  • PDF

시멘트 제조·취급사업장에서 발생하는 공기 중 분진의 노출평가 (Exposure Assessment of Airborne Dusts in the Cement Manufacturing and Handling Industries)

  • 배혜정;성은창;피영규
    • 한국산업보건학회지
    • /
    • 제27권4호
    • /
    • pp.390-397
    • /
    • 2017
  • Objectives: The purpose of this study was to evaluate concentrations in airborne total and respirable dusts in the cement manufacturing and handling industries. Methods: Fifty-three total dust and 42 respirable dustsamples were collected from 24 work places. Total dust samples were collected using a three-stage cassette. Respirable dust samples were collected using a cyclone equipped with a 37 mm, $5{\mu}m$ pore size PVC filter. Results: The geometric means of the dust concentrations were $0.10mg/m^3$ and $0.08mg/m^3$ in total dust and respirable dust, respectively. The Korean Occupational Exposure Limit($10mg/m^3$) was not exceeded, but the rate of exceeding the American Conference of Governmental Industrial Hygienist(ACGIH) Threshold Limit Value($1mg/m^3$) was 16.7%. Conclusion: When measuring the level of dust at cement manufacturers, the airborne concentration of respirable dust should be evaluated. In order to protect the health of workers exposed to cement dust, it is necessary to actively consider strengthening the Korean Occupational Exposure Limit.