US1854659A - Process of dressing coal - Google Patents

Description

April 1932- K. LEHMANN PRQCE SS 0F DRESSING COAL a Sheets-Sheet 1 Filed July 19. 1930 Inventor kavi ZJJZm/Qznh/ 3 Sheets-Sheet 2 Filed July 19, 1930- Kar'Z LeA-mazrrw Attorney Patented p 1 ,19 2 I 1,854,659

UNITED STATES PATEN'D- om n or seen, I I V ma on naassme con I Application me m 19, mo; sum No. 469,229, a in Germany a1, '31, ms.

The general purpose of the process of not been used for coalex pt possibly for the dressing coal, as heretofore practised, is to articular purpose of reducing the coal uniseparate shale and like impurities from the ormly to granules of a {particular size.- coal, which is done by a wet ora dry process, Elastic percussion or thezresilient disinte- 6 and tdg'rade the coal according to size, crushgrating action applied in accordance with my 55 ing alpparatus bein sometimes used as aids invention reduces the coal to anules or for t s purpose; on aded according lumps of different sizes, the sma est consistto size, by these methods, t e coal in the va.-' g of :Eusite, which is more or less friable,

fous grades is still in the main of fiPPl'OH- and the intermediate size being the brittle 10 mately uniform average petrographic and vitrite. The hard, resilient duriteresiststhe 00 chemical composition. e blows loigcest, and furnishes the largest The object of m invention is toefiect'the pieces. er the elastic percussion thethree dressing with gra 'ng of the coal according petro aphic constituents can easil be sepato itidpetrographic constituents. rated y screening or by other suita le means.

16 M an research has shown that coal, pre- The elastic percussion may be applied by 66 viously regarded as a substantially homogesub ecting the coal to elastic blows or taps, neous substance, consists in fact of three or byflin gor beatin it, asin a millwith constituent substantially difierent from each heaters. or example,t e coal maybe laced other, namely :-(1) Vitrite, (2) Durite, (3) in a rotating sifting drum in which t ereis Fusite. a shaft, rotating in the same or in the '0 po- In addition to purely physical difi'erences site direction, with elastic heater bars ed the chemical compositions of these constituthereto. In many cases it may be necesents differ substantially from each other, and sary to repeat the elastic percussive treatthe same are, accordingly, not all equally ment, in order thoroughly to separate the 25 well adapted for the same uses. Fusite, for intimately associated petrographic constitexample, is best adapted for powdered fuel uents of the raw coal. Separation of imfurnaces, and vitrite is best ada ted for cpk-. purities may precede this treatment, but it ing fusite and. durite being in eriorcok ng may be convenient to. first effect a prelimico Durite is best adapted'for gas1fica-' nary separation of the petro aphic conwtion, production of oil and various chemistituents, then clean the coal,an finall .com-

cal. rocemes. I I r plots the se aration of the trographic conelcllifl'ereiicesdin rbzgard to physigaiprtipstituent's. tle or: of c eanfcoal the elegerties ave a rea y n recogmze ere 0- tie rcussive rea ent isfio course su fore, and suggestions have been made for uti-S ficieii: for alt urpose L arti ulaid- 5 lizi'ng the same for grading the coal; It has I vantage of the process is that it can be Per.-

in fact been suggested inprint, that breaking f d h ll i 7 r I P the f 5 p l r sizes m y Pesult in In regard to the separation of the fusife: gp r fi gg gg gg gg g. it'is found that from the econoltngcvpoint of sic erences no 1 0 EH 6 been made to ascertain whether this g i g a p z g :2

method would Produce useful results. I@ s g. h 1 have found that ordinary methods of disinif 1 1% by gz g m? Shown tegrating, as employed in connection with i suction gf ,thedressmgof coal,arenotefl'ective forsepap 5 y y g 1m 3 rating the petrographic constituents, whereas fusih .2 comp. I 1 suchseparatiori'can be efiected by subjecting sepammona m v Tests have also shown that a vltnte content the coal to elast1c percussion or to resihent disintegrdting actiom Some known kinds-of P 'f' un 9 l p' apparatus sub'ject the-material may obtained. I I I I treated elastic percussion, but these have I One method of carrying the invention nto e;

effect and two forms of "mills are shown in the annexed drawings, in which 2- Figure 1 is a flow sheet illustrating the method,

Figure 2 is a vertical sectional view of a mill, and

Fi ure 3 is a vertical section of a modified orm of mill.

The coal is fed from a hopper a to a classifying drum or vibrating screen I), which separates it into granules of three sizes 1, 2 and 3. The coarsest coal is treated on cleaning bands 0 or by means of other suitable appliances for separation of the coarser impurities. A breaker d is provided for elastic treatment whereby preliminary separation according to petrographic constitution is effected, the separation being efiected so that the vitrite remains in the most finely divided coal, the vitrite in the middings, and the durite in the coarse coal. For this purpose a disintegrator may, for example, be used, the coal of sizes 1 and 2 being fed to the same. The coal discharged from the mill, together with the coal 3 from the screen 6, passes to the screen 0, which may be a vibrating screen and separates the coal according to three sizes 4, 5 and 6, which are delivered separately to three cleaning tables 9 with suction hoods, of a known type, for separating shale,

but the most finely divided coal first passes through a pneumatic sifter f. The most finely divided clean coal 7 taken from the cleaning tables consists almost exclusively of vitrite, and is conveyed away for use. The two coarser fractions 8 and 9 are fed to mills h with elastic beaters, which complete the separation according to petrographic constitution. The mills may, for example, consist of screening drums in which there are shafts with elastic heaters, rotating in the same direction as the-drums or in the opposite direction, at appropriate speeds, the fineness of the screens depending on the petrographic structure of the coal. The beaters may be arms elastically connected to the .shafts. By striking the coal they separate the vitrite from the durite, the former being discharged through the screen.v

The fine coal dust separated by the suction appliances at the various stages, particularly the cleaning tables and mills, is practically free from. durite, and consists mainly of fusite, with some vitrite. It is deposited and collected by means-of cyclone appliances 5, or in any other convenient way. Shale and other coarser impurities coming from the cleaning bands 0 and principally from the cleaning tables 9 are led. away on line B.

Substantially complete separation of the raw coal into. its petrographic constituents is thus effected, but in regard to detail the mode of procedure may be varied in many by appropriate phur to become concentrated'mainly in one of the fractions, so that separation thereof means is facilitated. Two forms of mills have been illustrated in Figures 2 and 3 in which Figure 2 consists essentially of a sieve drum 1 which surrounds a percussion device consisting of a plurality of elastic beater bars 3. These bars are pivoted as pendulums and are secured to the shaft 2 'of the mill by means of the circular disks 5. The drum 3 receives its rotation from the driving pulley 6 and the shaft 2 receives its rotation from the driving ulley 7 The material to be treated is place in the mill through the entry tube 8 and enters the interior of the drum -1 atthe ri ht end of the drum. The material after eing treated' leaves the drum at the left end by means of the openings 9. ,In this manner the coal I which is to be disintegrated will be repeatedly struck by the bars 3 and the coal will thus be divided into its three constituents in that the harder material, durite, which will be larger kernels, will be forced against the sides of the drum and eventually will fall into the container 10. The other particles vitrite and fusite which will beiin the form of smaller kernels will fallcthrough the sieve and will eventually be de osited into the container 11. The fusite is separated from the vitrite by suction so that eventually only the' vitrite will be contained in the container 11. The entire mill is disclosed in a dust-proof casing 12. I

In Figure 3 a modified form of mill is shown which consists of an outer casing or mantle 13 which surrounds the'inner mantle 14 arranged in the form of ste s. Centrall of the mill there is arranged a s aft 15 whic contains the beater arms 16 hav'ingattheir ends the beater 17. From the top to the bottom the beater arms progress m'length as.

through the mill. The finely divided vitrite and fusite will be forced through the sieves 18 and they will eventually fall through the outlet 21. However, the extremely fine fusite may be forced by suction through the outlet opening 20 at the top so that in that manner 1'25 the material fallingthrough the outlet21 is merely vitrite. The sieves 18 decrease in size from the top to the bottom but the durite which remains in the eventually fall through the bottom into the trough through the vibration sieve 23 and the very fine fusite remaining will be forced by suction out through the pipe 24.

I claim 1. A process of dressing coal, comprising subjecting the .coal to elastic percussion, whereby the fusite, durite and vitrite constituents are respectively broken up into granules of different sizes, and separating the granules of different sizes by screening.

2. A process of dressing coal, comprising subjecting the coal to whereby the fusite, durite and vitrite constituents are respectively broken up into granules of different sizes, separating the granules of durite and vitrite by screening, and removing the fusite by suction.

3. A process of dressing coal, comprising subjecting the coal to repeated elastic percussive treatments, whereby the, fusite, durite and vitrite constituents are respectively broken up into granules of diflt'erent sizes, separating the granules of durite and vitrite by screening, and removing the fusite by suction.

4; A process of dressing coal, comprising first subjecting the coal to elastic percussive treatment for preliminary division thereof into its fusite, durite and vitrite constituents, then separating the impurities from the coal, subjecting it to further plastic percussive treatment, whereby the said constituents are respectively broken up into granules of different sizes, and finally separating said granules of different sizes by screening.

5. A process of dressing coal, comprising subjecting the coal to repeated elastic percussive treatments, whereby the fusite, durite and vitrite constituents are respectively broken up into granules of different sizes, separating the granules of durite and vitrite by screenlng; and subjecting the coal to suction at the successive stages of treatment, whereby the fusite .is separated.

6. A process of grading coal by disintegration thereof and separation of the several macroscopic banded constituents, comprising in subjecting the coal to resilient disintegrating action whereby the constituents are broken up into granules of difi'erent sizes and separating the granules of different sizes.

In testimony whereof, I afiix my signature.

KARL LEHMANN.

elastic percussion,

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