• Title/Summary/Keyword: Magnetic Separation

Search Result 410, Processing Time 0.026 seconds

A Study on the Physical Separation Characteristics of Valuable Metals from the Waste Printed Wiring Boards (물리적 처리에 의한 폐 컴퓨터 기판으로부터 유가금속의 분리선별 특성 연구)

  • 현종영;채용배;정수복
    • Resources Recycling
    • /
    • v.11 no.1
    • /
    • pp.9-18
    • /
    • 2002
  • Printed wiring boards(PWBs) of the obsolete computers are composed of various organic and inorganic compounds as well as metals and alloys. As convinced that the valuable metals obtained from the PWBs are effectively utilized as secondary resources when recovered by economical methods, in this study, an investigation for characterizing the physical separation techniques is conducted. For the recovery of them, the sockets and chips dismantled from PWBs by scraping and residual resin boards are subjected to the appropriate separation processes according to the physical properties of each part. In the case of crushed socket scraps size ranged from -2.36 mm to +1.18 mm, approximately 97 wt% of the product obtained by magnetic separation consists of metallic compounds. In the case of chip scraps, 97% of Fe-Ni alloy and 95% of Cu metal are recovered by the combined process of air classification and dry magnetic separation in the size range from -2.36 mm to +0.15 mm. Ball milling is adopted in order to improve the removal efficiency of the thin-printed metallic materials on the residual resin boards and approximately 77% of Cu metal is recovered by zigzag separation after ball milling.

Mongolia Erden-soum tungsten development (몽골 에르덴솜 텅스텐광 개발을 위한 선별시스템 개발)

  • Kim, Su-Gang;Jeon, Ho-Seok;Baek, Sang-Ho;Kim, Byoung-Gon
    • Mineral and Industry
    • /
    • v.28
    • /
    • pp.1-13
    • /
    • 2015
  • In this study, it was carried out separation process research and development to be able to produce high-grade tungsten concentrate form tungsten taken form Mongolia. In order to reduce treatment cost and increase separation efficiency the jig separation at first was applied for recovering the concentrate. Which reground would make the degree of liberation increase. Which was treated by shaking table to reject the gangue minerals from the first concentrate. Because the heavier product contains not only ferberite but also cassiterite, the product was treated by further dry magnetic separation to obtain the ferberite concentrate. Finally, the high-grade ferberite concentrate of 67.63% $WO_3$ could be obtained with recovery of 86.07% through the separation process developed in this study.

  • PDF

High Purification Characteristics of Quartz with Physical Separation Method (물리적 정제방법에 의한 규석의 고순도화 연구)

  • Hyun Jong-Yeong;Jeong Soo-Bok;Chae Young-Bae
    • Journal of the Mineralogical Society of Korea
    • /
    • v.19 no.1 s.47
    • /
    • pp.1-5
    • /
    • 2006
  • In this study, we have investigated the purification characteristics of quartz which size was 0.1mm to 0.3 mm by using physical separation techniques. The A and B samples which contained 95,864 mg/kg and 4,568 mg/kg of impurities were reduced upto 126 mg/kg and 174 mg/kg of impurities, respectively. So, removal ratios of the total impurities were about 97.85 wt.% and 96.19 wt.%, individually. At that time, the yields of the purified quartz (over 99.98 wt.% $SiO_2$) were 79.05 wt.% and 75.43 wt.% by using purification process including magnetic separation, gravity separation and scrubbing process. The most benefit in purification process of both different raw materials for iron element can be achieved by magnetic separation. Also, gravity separation is extremely successful for reducing aluminium element.

Dependence of the peak fluxes of solar energetic particles on CME parameters and magnetic connectivity

  • Park, Jinhye;Moon, Yong-Jae;Lee, Harim;Kahler, S.W.
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.42 no.2
    • /
    • pp.82.3-83
    • /
    • 2017
  • We investigate the relationships between the peak fluxes of 18 solar energetic particle (SEP) events and associated coronal mass ejection (CME) 3D parameters (speed, angular width, and separation angle) obtained from SOHO, STEREO-A and/or B for the period from 2010 August to 2013 June. We apply the STEREO CME Analysis Tool (StereoCAT) to the SEP-associated CMEs to obtain 3D speeds and 3D angular widths. The separation angles are determined as the longitudinal angle between flaring regions and magnetic footpoints of the spacecraft, which are calculated by the assumption of Parker spiral field. The main results are as follows. 1) We find that the dependence of the SEP peak fluxes on CME 3D speed from multi-spacecraft is similar to that on 2D CME speed. 2) There is a positive correlation between SEP peak flux and 3D angular width from multi-spacecraft, which is much more evident than the relationship between SEP peak flux and 2D angular width. 3) There is a noticeable anti-correlation (r=-0.62) between SEP peak flux and separation angle. 4) The multiple regression method between SEP peak fluxes and CME parameters shows that the longitudinal separation angle is the most important parameter, and the CME 3D speed is secondary on SEP peak flux.

  • PDF

The Creation of a Strong Magnetic Field by Means of Large Magnetic Blocks from NdFeB Magnets in Opposing Linear Halbach Arrays

  • Zezulka, Vaclav;Straka, Pavel
    • Journal of Magnetics
    • /
    • v.21 no.3
    • /
    • pp.364-373
    • /
    • 2016
  • The article presents the results and findings obtained through the assembly of opposing linear Halbach arrays from two magnet layers using large magnetic blocks from permanent NdFeB magnets, especially concerning the distribution of magnetic induction in an air gap. The use of these large blocks has led to a significant expansion of the area of magnetic field with a substantially higher value of magnetic induction in comparison with similar linear Halbach arrays composed of small magnets. The paper also discusses the determined dependences of magnetic induction on the parameters of the x, y, z coordinate system and indicates the possibilities of achieving an even stronger magnetic field in a larger volume of an air gap for application for instance in equipment for magnetic separation of raw materials, in instrument technologies and in other areas.

Size Control of Iron Oxide (Fe3O4) Nanoclusters according to Reaction Factors and Consequent Change in Their Magnetic Attraction (반응 인자 제어에 의한 산화철(Fe3O4) 나노클러스터의 크기와 자기 특성 조절)

  • Sanghoon Lee;Arim Byun;Jin-sil Choi
    • Journal of Powder Materials
    • /
    • v.30 no.4
    • /
    • pp.297-304
    • /
    • 2023
  • Iron oxide (Fe2O3) nanoclusters exhibit significant potential in the biomedical and pharmaceutical fields due to their strong magnetic properties, stability in solutions, and compatibility with living systems. They excel in magnetic separation processes, displaying high responsiveness to external magnetic fields. In contrast to conventional Fe2O3 nanoparticles that can aggregate in aqueous solutions due to their ferrimagnetic properties, these nanoclusters, composed of multiple nanoparticles, maintain their magnetic traits even when scaled to hundreds of nanometers. In this study, we develop a simple method using solvothermal synthesis to precisely control the size of nanoclusters. By adjusting precursor materials and reducing agents, we successfully control the particle sizes within the range of 90 to 420 nm. Our study not only enhances the understanding of nanocluster creation but also offers ways to improve their properties for applications such as magnetic separation. This is supported by our experimental results highlighting their size-dependent magnetic response in water. This study has the potential to advance both the knowledge and practical utilization of Fe2O3 nanoclusters in various applications.

Magnetic-activated cell sorting improves high-quality spermatozoa in bovine semen

  • de Assumpcao, Teresinha Ines;Severo, Neimar Correa;Zandonaide, Joao Pedro Brandao;Macedo, Gustavo Guerino
    • Journal of Animal Reproduction and Biotechnology
    • /
    • v.36 no.2
    • /
    • pp.91-98
    • /
    • 2021
  • The objective of this study was to establish a selection process for high quality sperm in bovine semen using sperm separation by magnetic activation (MACS). For this, semen from 21 Nellore bulls was collected using an artificial vagina. To guarantee the presence of pathologies in the ejaculate, animals previously declassified in four consecutive spermiogram were used. Semen was analyzed in five statuses: (1) fresh semen (fresh); (2) density gradient centrifugation (DGC), percoll column; (3) non-apoptotic fraction after separation by MACS (MAC); (4) apoptotic fraction from the separation (MACPOOR); and (5) MAC followed by DGC (MACDGC). Using a computerized analysis system (CASA), motility was measured. The sperm morphology was evaluated by phase contrast, and the supravital test was completed with eosin/nigrosin staining. For DGC, 20 × 106 cells were used in a gradient of 90% and 45% percoll. MACS used 10 × 106 cells with 20 μL of nanoparticles attached to annexin V, and filtered through the MiniMACS magnetic separation column. Membrane integrity was assessed with SYBR-14/IP and mitochondrial potential with JC-1 by flow cytometry. Processing sperm by MACDGC, was more effective in obtaining samples with high quality sperm, verified by the total of abnormalities in the samples: 35.04 ± 2.29%, 21.50 ± 1.47%, 17.30 ± 1.10%, 30.68 ± 1.94% and 10.50 ± 1.46%, respectively for fresh, DGC, MAC, MACPOOR, and MACDGC. The subpopulation of non-apoptotic sperm had a high number of live cells (82.65%), membrane integrity (56.60%) and mitochondrial potential (83.98%) (p < 0.05). These findings suggest that this nanotechnological method, that uses nanoparticles, is efficient in the production of high-quality semen samples for assisted reproduction procedures in cattle.

Survey on electrocoagulation to purify contaminated water (전기응고법을 이용한 오염 수 정화)

  • Kim, W.Y.;Park, K.S.;Oh, C.S.
    • Journal of Energy Engineering
    • /
    • v.23 no.3
    • /
    • pp.17-20
    • /
    • 2014
  • A magnetic fluid separation technology was confirmed to be very effective to remove the suspended solids from contaminated water. We have surveyed on the effects of operating variables on the characteristics of suspended solids(SS) removal investigated through the test runs using magnetic powder. Magnetic flocculation here formed by adsorbing fine magnetites on the surface of suspended solid was observed. The strength of magnet was of significance in determining the SS removal efficiency.

Active control of flow over a sphere using electro-magnetic actuators (전자석 액츄에이터를 이용한 구 주위의 유동제어)

  • Park, Jin-Il;Choi, Hae-Cheon;Jeon, Woo-Pyung
    • Proceedings of the KSME Conference
    • /
    • 2000.04b
    • /
    • pp.497-501
    • /
    • 2000
  • Flow over a sphere is controlled experimentally at $Re=10^5$ using electro-magnetic actuators. The electro-magnetic actuator developed in this study is composed of the permanent magnet electro-magnet membrane and slot. Eight actuators are placed inside the sphere at equally spaced intervals on a latitudinal plane and the position of the control slot is 76 from the stagnation point. Each actuator generates a periodic blowing and suction through the slot at variable frequencies of $10{\sim}140Hz$ and variable amplitudes by controlling electric signals applied to the electro-magnet. Drag on the sphere measured using a load cell is significantly reduced with control at the forcing frequencies larger than the natural shedding frequency $({\approx}14Hz\;at\;Re=10^5)$, whereas drag is slightly increased at the forcing frequency of 10Hz. It is shown from pressure measurement that the static pressure in the rear surface of the sphere is significantly increased with control, indicating that the separation is delayed due to control. Flow visualizations also show that the detaching shear layer is more attracted to the sphere center with control, the separation bubble size is significantly reduced, and motion inside the bubble is very weak, as compared to the case of uncontrolled flow.

  • PDF

Study on magnetic separation of waste water using superconducting magnet (초전도 전자석을 이용한 제철소 폐수처리용 자기분리 연구)

  • Ha, Dong-Woo;Kim, Tae-Hyung;Oh, Sang-Soo;Ha, Hong-Soo;Park, Sung-Kook;Lee, Sang-Gil;Roh, Yu-Mi
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2006.06a
    • /
    • pp.87-88
    • /
    • 2006
  • It is needed several large reservoirs and long time in order to remove suspended solid like steel fines and iron oxide at steel making factory. If removing rate of suspended solid in rolling coolant is improved, the productivity of working process can be increased and the area of reservoir can be reduced. Pre-treatment to add extra magnetization of suspended solid was studied Iron hydroxide and electrolytic dissociation were used for pretreatment. High gradient magnetic separation (HGMS) system was used for removing of magnetized suspended solid. Removing ratio showed over than 99% in the coolant containing magnetic fines. Magnetic properties of suspended solid were investigated after mixed with Al2(SO2)3 and organic flocculant by using electrochemical treatment.

  • PDF