Classifying – separating – and assorting solids – Plural – diverse separating operations – Aqueous suspension and sifting
Patent
1992-12-09
1994-09-20
Lithgow, Thomas M.
Classifying, separating, and assorting solids
Plural, diverse separating operations
Aqueous suspension and sifting
209 39, 2091725, 209214, 209 38, 209727, 209734, 241 20, 241 24, 423633, 423634, 252 60, B03B 534, B04C 500, C01G 4902
Patent
active
053481607
ABSTRACT:
Fine particle coal is beneficiated in specially designed dense medium cyclones to improve particle acceleration and enhance separation efficiency. Raw coal feed is first sized to remove fine coal particles. The coarse fraction is then separated into clean coal, middlings, and refuse. Middlings are comminuted for beneficiation with the fine fraction. The fine fraction is deslimed in a countercurrent cyclone circuit and then separated as multiple fractions of different size specifications in dense medium cyclones. The dense medium contains ultra-fine magnetite particles of a narrow size distribution which aid separation and improves magnetite recovery. Magnetite is recovered from each separated fraction independently, with non-magnetic effluent water from one fraction diluting feed to a smaller-size fraction, and improving both overall coal and magnetite recovery. Magnetite recovery is in specially designed recovery units, based on particle size, with final separation in a rougher-cleaner-scavenger circuit of magnetic drum separators incorporating a high strength rare earth magnet.
REFERENCES:
patent: 2075542 (1937-03-01), Pruyn
patent: 2696299 (1954-12-01), Van Os
patent: 2701641 (1955-02-01), Krijgsman
patent: 2819795 (1958-01-01), Fontein et al.
patent: 2870003 (1959-01-01), Cavanagh
patent: 2932395 (1960-04-01), Marot
patent: 2950955 (1960-08-01), Wagner
patent: 3034884 (1962-05-01), Meyer et al.
patent: 3084796 (1963-04-01), Skolnik
patent: 3353673 (1967-11-01), Visman
patent: 3371794 (1968-03-01), Johnson
patent: 3378335 (1968-04-01), Ellis et al.
patent: 3794162 (1974-02-01), Miller et al.
patent: 3908912 (1975-09-01), Irons et al.
patent: 4010239 (1977-03-01), Dor
patent: 4028228 (1977-06-01), Ferris et al.
patent: 4133747 (1979-01-01), Visman
patent: 4140628 (1979-02-01), Horsfall
patent: 4175035 (1979-11-01), Moyer, Jr.
patent: 4219409 (1980-08-01), Liller
patent: 4244530 (1981-01-01), Halvorsen
patent: 4282088 (1981-08-01), Ennis
patent: 4283232 (1981-08-01), Best
patent: 4341352 (1982-07-01), Liller
patent: 4364822 (1982-12-01), Rich
patent: 4400267 (1983-08-01), Brose
patent: 4406781 (1983-09-01), Nightingale
patent: 4436681 (1984-03-01), Barczak et al.
patent: 4478601 (1984-10-01), Stephens
patent: 4676809 (1987-06-01), Fjallstrom et al.
patent: 4737271 (1988-04-01), Childs
patent: 4777031 (1988-10-01), Senecal
patent: 4793925 (1988-12-01), Duvall
patent: 4802976 (1989-02-01), Miller
patent: 4830741 (1989-05-01), Ferencz et al.
patent: 4865740 (1989-09-01), Callut
patent: 5022892 (1992-06-01), Klima et al.
patent: 5096066 (1992-03-01), Kindig
patent: 5108626 (1992-04-01), Lees et al.
patent: 5153838 (1992-10-01), Kindig
patent: 5277368 (1994-01-01), Kindig
Deurbrouck, "Washing Fine Sized Coal in A Dense Medium Cyclone", Bureau of Mines Report No. 7982, 1974.
Deurbrouck, et al., "Performance Characteristics of Coal Washing Equipment Dense Medium Cyclones", Bureau of Mines Report #7673, 1972.
Sokaski et al. "Cleaning Unsized Fine Coal in a Dense-Medium Cyclone Pilot Plant", Bureau of Mines Report #6274, 1963.
Herkenhoff, "Selecting A Cyclone for Wet Classification" Mining Engineering, Aug. 1957.
D. A. Dahlstrom, "High-Speed Classification and Desliming With the Liquid-Solid Cyclone", Transactions of AIME, vol. 190, Feb. 1951, Mining Engineering pp. 153-165.
Foreman, William E., Current Status of Hydrocyclone Technology, Mining Congress Journal, 1972.
Arterburn, The Sizing of Hydrocyclones, Krebs Engineering (Oct. 1976).
Fourie, et al., The Beneficiation of Fine Coal by Dense-Medium Cyclone, Journal of South African Institute of Mining and Metallurgy, pp. 357-361 (Oct. 1980).
Gochin, et al., Dense Medium Separation, Mining Magazine, pp. 453-467 (Dec. 1983).
Menglers, et al., HM Cyclones, If Run on Brine Medium, Offer Sharper Separation of Coal Fines, Coal Mining and Processing, pp. 78-80 (Sep. 1982).
Geer, et al., Preliminary American Tests of a Cyclone Coal Washer Developed in the Netherlands, Transactions of the American Institute of Mining and Metallurgical Engineers, Coal Division, vol. 177, pp. 220-229 (1948).
Lotzien, et al., Cleaning of Ultra-Fines in Heavy Liquid Cyclones, Aufbereitungs-Technik, vol. 28, No. 10, pp. 563-570 (W. Germany, Oct. 1987).
Chakaravarti, et al., A Study of the Operation of a 6 in. Diameter Cyclone Washer, Journal of the Institute of Fuel, pp. 612-622 (Great Britian, Nov. 1957).
Stoessner, et al., Optimization of Dense Medium Cyclone Performance for Low Gravity, Fine Coal Cleaning (1986).
Bradley, The Hydrocyclone, Pergamon Press Ltd., pp. 19-40, 48-62 and 107-133 (1965).
Durham, et al., Power Plant Fly Ash Magnetite Performs Well in Coal Cleaning, Power Engineering, pp. 52-55 (Apr. 1986).
Nielson, et al., Ultrafine Metal Oxides by Decomposition of Salts in a Flame, Symposium on Ultrafine Particles, 1961, Indianapolis, pp. 181-195 (Wiley, New York 1963).
Ruthner, et al., Spray-Roasted Iron Oxide for the Production of Ferrites, Ferrites: Proceedings of the International Conference, Jul. 1970, Japan, pp. 75-78.
Genesis Research Corporation
Lithgow Thomas M.
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