US1171583A - Ore-roasting apparatus. - Google Patents

Ore-roasting apparatus. Download PDF

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US1171583A
US1171583A US4499015A US4499015A US1171583A US 1171583 A US1171583 A US 1171583A US 4499015 A US4499015 A US 4499015A US 4499015 A US4499015 A US 4499015A US 1171583 A US1171583 A US 1171583A
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ore
cylinder
shelves
roasting
furnace
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US4499015A
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Harrison T Benson
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WINFIELD S BARNES
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WINFIELD S BARNES
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    • EFIXED CONSTRUCTIONS
    • E01CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
    • E01CCONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
    • E01C19/00Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving
    • E01C19/02Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving for preparing the materials
    • E01C19/05Crushing, pulverising or disintegrating apparatus; Aggregate screening, cleaning, drying or heating apparatus; Dust-collecting arrangements specially adapted therefor
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27BFURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B7/00Rotary-drum furnaces, i.e. horizontal or slightly inclined
    • F27B7/20Details, accessories, or equipment peculiar to rotary-drum furnaces
    • F27B7/34Arrangements of heating devices

Definitions

  • My invention relates to apparatus for roasting ore,-and particularly to that class of apparatus in which the ore is fed into a roasting cylinder which is constantly rotated, the ore being carried from the inlet end of the cylinder to the discharge end thereof-and there ejected.
  • the primary obj ectof my invention is the provision of a roasting furnace ofthis type wherein means are. provided for preventing, 1 the pulverizing of the, particles of'dre and:
  • a further object of my invention 'isto improve the means whereby the heating agent in the form of a blast is injected into the furnace, and specifically to improve the constructionof the blast tube so as to secure a greater distribution of'heat, and in this conmotion to improve the means whereby air is support comadmitted to the furnace to bustion.
  • Still another object is the provision .of means whereby the dust, products of combustion and the gases arising from the roasting ore are carried up into a settlingcham-l gases eventually passed into' a ber, and the condenser.
  • V '1 Still anotherobject is to improve upon the details of construction of ore roasters of this character. r My invention is illustrated in the panying drawings, wherein:
  • Figure 1 1s a longitudinal sectional view of a furnace constructed in accordance wi th my invention, and of the settling tank-and of large quart accom- Specification of Letters Patent. Patent d F b. 15 1916.
  • my improved roasting furnace comprises a cylinder 2, which, as illustrated, is preferably made up of a plurality of sec- 'tions having abutting flanges 3 which are bolted toeach other. All of the sections are open ended.
  • the cylinder is rotatably mounted upon two sets of rollers 4 which are disposed each set on one Side of the mlddle vertical plane of the furnace. These rollers .are mounted upon shafts 5.
  • the cylinder is likewise supported upon a series of idler rollers 6 which are supported in suitable bearlngs on the base 7 and'preferably the cylinder is rotated by means of a toothed annulus 8 mounted upon the cylinder at any desired point and engaged by a gear wheel 9 j V mounted upon one of the shafts 5.
  • One or condenser; Fig. 2 is a side elevation of the;
  • Fig.. 1 the settling tank and condenser 'being omitted;
  • Fig. 3 is a front end elevation of the construction" shown in Rig. 2;
  • Fig. 4 is a face view ofv the,
  • Fig. 5 is a transverse section of" cap 23; 1 the ore roasting cylinder. 4
  • This plate 22 which forms the end of the furnace is provided with a central opening having an outwardly flaring flange 25. Disposed within the central opening in the plate 22 and extending out beyond the flaring flange'25 is a blast pipe 26 whereby the blast of ignited gas may be injected into the furnace.
  • the end of this blast pipe 26 is closed by means of a baflie plate 27 butthe upper face of the pipe is formed with a laterally extending slot 28.
  • the blast of ignited gas is directed upward and toward the side walls of the furnace, and the heat is more fully dis tributed than it would be if the blast pipe 26 opened at its end or were provided with a relatively small opening directed toward one point of the furnace.
  • any source of gas to the pipe 26 may be employed, as, for exam-v ple, the pipe 26 shown conventionally in Fig. 1.
  • the end wall 22 is also formed with an air inlet opening 29 whose area is controlled by means of a damper 30 as illustrated in Fig. 4.
  • This damper is rectangular in form and is pivoted at one corner as at 31 and operates between the end plate 22 and an arcuate strip 32- which is perforated.
  • a pin passes through the damper plate'and through any desired perforation in the arcuate strip so that the damper plate may be held in any adjusted position and thus the amount of air assing into the opening 29 to support com ustion within the furnace may be controlled.
  • the hood 14 is formed with an outlet opening 33 from which extends a flue -34provided with a damper 35 and with valved air inlet openings 34 and this flue opens into a chamber 36.
  • This chamber is a settling chamber and is provided with a plurality of baflie walls 37 arranged in staggered relation so that the products of combustion together with the dust and gases which may be driven off through the flue 34 will be caused to take.
  • products of combustion may be afterward removed byopening the bottom of the chain'- ber, this bottom :being normally held. closed by means of a bolt 38.
  • the gases which have been to a large extent purified of solid particles are carried by means of the pipe 39 to a con and removed by means of the pipe 43 into a barrel Or other receptacle while the remain dcr of the gases pass off through the flue 44 in a thoroughly purified condition.
  • each section Extending longitudinally along the wall of the cylinder on the inner face thereof and cast with each section are a plurality of shelves 45. These shelves are inclined downward from one end of the cylinder to the 1 other, and each shelf is formed in cross section. as illustrated in Fig. 5, that is, assuming that the cylinder is rotating in the direction of the arrow in Fig. 5, the rear faces of the shelves are radial to the axis of rotation of the cylinder while the forward faces of the shelves are inclined relative 'to the radial faces.
  • the blades or shelves will not act to push the ore around but will roll the ore over.
  • the ore will be gradually fed forward to the discharge end of the cylinder as it is turned.
  • the discharge end of the cylinder is formed with a discharge opening 46 whereby the ore which has been fully roasted is discharged.
  • the inclination of the shelves is such that the ore is moved relatively slowly through the cylinder so that it may be thoroughly actedupon by the heat. Further more, it will be seen that the greatest heat will be at the discharge end of the cylinder and the ore will be gradually raised in temperature as it moves forward.
  • one of the main objects ofthis invention is to prevent the pulverizing of the ore by agitating the contents of the.
  • roasting cylinder shelves 'extendinglon'gitw dinally on the inside face ofthe cylinder I and inclined relative to the longitudinal axis thereof," the forward faces of the, shelves being inclined centrally-and-Irearward whereby the ore may roll from-the shelves .after theshelves have risen a relativelys'hort dis-' tance abo ve the ore bed. 7
  • An, ore roasting furnace including a roasting cylinder, means for, rotatin 'said cylinder, shelves extending longitu inally cylinder and having a downwardly directed on. the inside face of the cylinder and inclined relative to the longitudinal axis there .of, the forward faces ofthe shelves being inclined centrally and rearward whereby the oremay roll from the shelves after the shelves have risen a relatively short distance abovethe ore bed,'a' stationary hood inclosing one end of said cylinder and having an opening extending therethrough, and a feed pipe extending through said 'hood and mounted therein and projecting into the ignited gases ejected from'the-blast' pipe and Y I g extending slot.
  • terminal portion discharging ore at a point adjacent the bottom of'the cylinder.
  • An ore roasting furnace including a roasting cylinder, a rotatable cylinder, shelves mounted upon the inner face of the of and inclined relative to the longitudinal axis, the forward faces of the blades being inclined centrally and rearward relative to the direction of motion of the cylinder, and a feed pipe entering one end of the,cylinder and having a downwardly directed terminal portion discharging ore at a point adjacent the bottom of the cylinder.
  • An ore roasting furnace including a cylinder, means for supporting same, a cap closing one end of'said cylinder,.and a blast pipe entering said cylinder through saidcap and provided at its inner end with a battle 1 plate, as specified, and at said plate and on pipe with a laterally the upper face of the 5.
  • An ore roasting furnace comprising a shelves extending on the inside faces of the tudinal axis thereof, the forward faces of the shelves being inclined centrally and rear- Ward whereby the ore will roll from the shelves after the latter have risen a relatively short distanceabove the ore bed, a hood inclosing the receiving end of said cylinder,a feed pipe supported in said hood .and extending therefrom into the cylinder,

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Description

H. T. BENSON.
ORE ROASTING APPARATUS.
APPLlCATiON FILED AUG.H| 1915.
Patented Feb. 15, 1916.
2 SHEETSSHEET 1.
Swami 1km H. T Benson attain;
H. T. BENSON.
ORE ROASTING APPARATUS.
APPLICATION FILED AUG.1I, 1915. 1,171,583. Patented Feb. 15,1916.
2 SHEETS-SHEET 2- anoantoz H. TBnson attain,
UNITED STATES PATENT OFFICE. HARRISoN '1. BENSON, 0P DENVEREOLORADO, ASSIGNOR 0P oNE-HAPP T0 wINPInm) v s. BARNES, 0P PHILADELPHIA, PENNSYLVANIA.
oRE-RoAS'rINe APPAR TUS.
To all whom it may concern:
Be it known that I, HARRISON T. BE SON, a citizen .of the United States, residing at Denver, in the county of Denver and State of Colorado, have invented certain new and useful Improvements in Ore-Roasting Apparatus, of which the following is a specification, reference being had to the accompanying drawings.
My invention relates to apparatus for roasting ore,-and particularly to that class of apparatus in which the ore is fed into a roasting cylinder which is constantly rotated, the ore being carried from the inlet end of the cylinder to the discharge end thereof-and there ejected.
The primary obj ectof my invention is the provision of a roasting furnace ofthis type wherein means are. provided for preventing, 1 the pulverizing of the, particles of'dre and:
the too great agitation of the latter which would cause the detachment tities of dust particles. I V I A further object of my invention 'isto improve the means whereby the heating agent in the form of a blast is injected into the furnace, and specifically to improve the constructionof the blast tube so as to secure a greater distribution of'heat, and in this conmotion to improve the means whereby air is support comadmitted to the furnace to bustion.
Still another object is the provision .of means whereby the dust, products of combustion and the gases arising from the roasting ore are carried up into a settlingcham-l gases eventually passed into' a ber, and the condenser. V '1 Still anotherobject is to improve upon the details of construction of ore roasters of this character. r My invention is illustrated in the panying drawings, wherein:
Figure 1 1s a longitudinal sectional view of a furnace constructed in accordance wi th my invention, and of the settling tank-and of large quart accom- Specification of Letters Patent. Patent d F b. 15 1916.
Application filed August 11, 1915. Serial No. 44,990..
I seen that my improved roasting furnace comprises a cylinder 2, which, as illustrated, is preferably made up of a plurality of sec- 'tions having abutting flanges 3 which are bolted toeach other. All of the sections are open ended. The cylinder is rotatably mounted upon two sets of rollers 4 which are disposed each set on one Side of the mlddle vertical plane of the furnace. These rollers .are mounted upon shafts 5. The cylinder is likewise supported upon a series of idler rollers 6 which are supported in suitable bearlngs on the base 7 and'preferably the cylinder is rotated by means of a toothed annulus 8 mounted upon the cylinder at any desired point and engaged by a gear wheel 9 j V mounted upon one of the shafts 5. One or condenser; Fig. 2 is a side elevation of the;
furnace. shown in Fig.. 1, the settling tank and condenser 'being omitted; Fig." 3 is a front end elevation of the construction" shown in Rig. 2; Fig. 4 is a face view ofv the,
and Fig. 5 is a transverse section of" cap 23; 1 the ore roasting cylinder. 4
Referring to these drawings, it be both, of the shafts 5 at its rear end is Opera'- ti'jvely connected as by means of a belt 9 to a counter Shaft 10 in turn driven from a line shaft 11. This counter shaft 10 at one end carries 'thbelt pulleys 12 whereby the mechanism for feeding the ore is driven. Each of hood 14 is non-rotatable and is supported by means of the bridge wall 15 or in any other,
suitable manner.
Extending into a central "openin in the y hood la-is'affeed' tube 16. This tu outer end iis'provided with the. receiving hopper 17 into-"which anorespout'18 dis; charges leading from a source of ore supply.
downwardly, directed spout"19.f This spout discharges relativelgadjacent} to the lower f there iisi pr'ovi ed the 'screwa'conveyer 20: i
tdeire h 2 i hi ei tu s' 1 driven by -iabeltfllf from fth'eipulleys 12.
' pulleysjare used upon;" 'the'...shaft s 10 1 (and 21' so, that the speed of rotation 'o'fjthe .portiomof-"the-Yc" lin r.v Withinrthetube 16- shaft flk may be regulated. 1
Q-Theop Siteend ofthe cylinder confronts f I '1 a cap plate 22 having an inwardlyextending i 96' I The tube 16 extends into the adjacent end of p the cylinder and then is'provided with a I annular flange 23 which is spaced from the circumferentially considered at the bottom,
as indicated at 23, to provide a discharge opening for the roasted ore. This plate 22 which forms the end of the furnace is provided with a central opening having an outwardly flaring flange 25. Disposed within the central opening in the plate 22 and extending out beyond the flaring flange'25 is a blast pipe 26 whereby the blast of ignited gas may be injected into the furnace. The end of this blast pipe 26 is closed by means of a baflie plate 27 butthe upper face of the pipe is formed with a laterally extending slot 28. Thus the blast of ignited gas is directed upward and toward the side walls of the furnace, and the heat is more fully dis tributed than it would be if the blast pipe 26 opened at its end or were provided with a relatively small opening directed toward one point of the furnace. Any source of gas to the pipe 26 may be employed, as, for exam-v ple, the pipe 26 shown conventionally in Fig. 1. The end wall 22 is also formed with an air inlet opening 29 whose area is controlled by means of a damper 30 as illustrated in Fig. 4. This damper is rectangular in form and is pivoted at one corner as at 31 and operates between the end plate 22 and an arcuate strip 32- which is perforated. A pin passes through the damper plate'and through any desired perforation in the arcuate strip so that the damper plate may be held in any adjusted position and thus the amount of air assing into the opening 29 to support com ustion within the furnace may be controlled.
In the opposite end of the furnace the hood 14 is formed with an outlet opening 33 from which extends a flue -34provided with a damper 35 and with valved air inlet openings 34 and this flue opens into a chamber 36. This chamber is a settling chamber and is provided with a plurality of baflie walls 37 arranged in staggered relation so that the products of combustion together with the dust and gases which may be driven off through the flue 34 will be caused to take.
a circuitous course and are prevented from rapid movement so that the dust and solid particles discharged through the pipe 34 will have a chance to settle and collect within the chamber 36. Thus any valuable matter contained in the dust driven off with the.
products of combustion may be afterward removed byopening the bottom of the chain'- ber, this bottom :being normally held. closed by means of a bolt 38. From the settling chamber the gases which have been to a large extent purified of solid particles are carried by means of the pipe 39 to a con and removed by means of the pipe 43 into a barrel Or other receptacle while the remain dcr of the gases pass off through the flue 44 in a thoroughly purified condition.
Extending longitudinally along the wall of the cylinder on the inner face thereof and cast with each section are a plurality of shelves 45. These shelves are inclined downward from one end of the cylinder to the 1 other, and each shelf is formed in cross section. as illustrated in Fig. 5, that is, assuming that the cylinder is rotating in the direction of the arrow in Fig. 5, the rear faces of the shelves are radial to the axis of rotation of the cylinder while the forward faces of the shelves are inclined relative 'to the radial faces. Thus as the cylinder rotates the blades or shelves will not act to push the ore around but will roll the ore over. Some part of the ore will of course be carried up on these shelves but the inclination of the forward face of each shelf will be such that as the shelf rises the ore will gently roll off the shelf back to the bed of roasting ore and will not be carried up the upper portion of the cylinder and then dropped as would be ifthe forward faces of the shelves were radial to the axis of rotation of the cylinder.
Furthermore, as the shelves are inclined with relation to the axis of the cylinder the ore will be gradually fed forward to the discharge end of the cylinder as it is turned. The discharge end of the cylinder is formed with a discharge opening 46 whereby the ore which has been fully roasted is discharged. The inclination of the shelves is such that the ore is moved relatively slowly through the cylinder so that it may be thoroughly actedupon by the heat. Further more, it will be seen that the greatest heat will be at the discharge end of the cylinder and the ore will be gradually raised in temperature as it moves forward.
As before stated, one of the main objects ofthis invention is to prevent the pulverizing of the ore by agitating the contents of the.
'feeding tube 16 and would tend to break up and create dust. By providing the spout 19, however, the ore simply fills into the spout and gently feeds into the cylinden' I have The operation of my invention will be understood from what has gone before. Ore roasting furnaces of this type'are well known and the advantages of my specific construction will be obvious to any one skilled in they art of roasting ore.- I
It will be noted that I attain economy of fuel by securing perfect combustion. This perfect combustion is secured'by adjusting the damper plate so that just .the proper amount of air is allowed topass into the" roasting furnace as 'willfcombine with the support combustion.
I claim is:
, roasting cylinder, shelves 'extendinglon'gitw dinally on the inside face ofthe cylinder I and inclined relative to the longitudinal axis thereof," the forward faces of the, shelves being inclined centrally-and-Irearward whereby the ore may roll from-the shelves .after theshelves have risen a relativelys'hort dis-' tance abo ve the ore bed. 7
2. An, ore roasting furnace, including a roasting cylinder, means for, rotatin 'said cylinder, shelves extending longitu inally cylinder and having a downwardly directed on. the inside face of the cylinder and inclined relative to the longitudinal axis there .of, the forward faces ofthe shelves being inclined centrally and rearward whereby the oremay roll from the shelves after the shelves have risen a relatively short distance abovethe ore bed,'a' stationary hood inclosing one end of said cylinder and having an opening extending therethrough, and a feed pipe extending through said 'hood and mounted therein and projecting into the ignited gases ejected from'the-blast' pipe and Y I g extending slot.
Having thus described my'invention,-what rotatable cylinder, means for rotating same,
1. An ore roastingfurnace including a cylinder and inclined relative to the longi- Witnesses:
terminal portion discharging ore at a point adjacent the bottom of'the cylinder.
' 3. An ore roasting furnace including a roasting cylinder, a rotatable cylinder, shelves mounted upon the inner face of the of and inclined relative to the longitudinal axis, the forward faces of the blades being inclined centrally and rearward relative to the direction of motion of the cylinder, anda feed pipe entering one end of the,cylinder and having a downwardly directed terminal portion discharging ore at a point adjacent the bottom of the cylinder. p
I 4. An ore roasting furnace, including a cylinder, means for supporting same, a cap closing one end of'said cylinder,.and a blast pipe entering said cylinder through saidcap and provided at its inner end with a battle 1 plate, as specified, and at said plate and on pipe with a laterally the upper face of the 5., An ore roasting furnace, comprising a shelves extending on the inside faces of the tudinal axis thereof, the forward faces of the shelves being inclined centrally and rear- Ward whereby the ore will roll from the shelves after the latter have risen a relatively short distanceabove the ore bed, a hood inclosing the receiving end of said cylinder,a feed pipe supported in said hood .and extending therefrom into the cylinder,
HARRISON T. BENSON.
Jos. F. X. QUINN, Enwoon L. KIEME.
US4499015A 1915-08-11 1915-08-11 Ore-roasting apparatus. Expired - Lifetime US1171583A (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2507123A (en) * 1947-01-31 1950-05-09 Int Nickel Co Rotary kiln for chemical and metallurgical processes
US2549787A (en) * 1947-11-21 1951-04-24 John B Dube Calcining kiln
US2705133A (en) * 1951-11-13 1955-03-29 Barber Greene Co Apparatus for heating and mixing paving materials
US5082534A (en) * 1990-03-14 1992-01-21 Wayne Technology, Inc. Pyrolytic conversion system
US5225044A (en) * 1990-03-14 1993-07-06 Wayne Technology, Inc. Pyrolytic conversion system
US5258101A (en) * 1990-03-14 1993-11-02 Wayne Technology Corp. Pyrolytic conversion system
US10195576B2 (en) * 2014-03-31 2019-02-05 Danmarks Tekniske Universitet Rotor for a pyrolysis centrifuge reactor

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2507123A (en) * 1947-01-31 1950-05-09 Int Nickel Co Rotary kiln for chemical and metallurgical processes
US2549787A (en) * 1947-11-21 1951-04-24 John B Dube Calcining kiln
US2705133A (en) * 1951-11-13 1955-03-29 Barber Greene Co Apparatus for heating and mixing paving materials
US5082534A (en) * 1990-03-14 1992-01-21 Wayne Technology, Inc. Pyrolytic conversion system
US5225044A (en) * 1990-03-14 1993-07-06 Wayne Technology, Inc. Pyrolytic conversion system
US5258101A (en) * 1990-03-14 1993-11-02 Wayne Technology Corp. Pyrolytic conversion system
US10195576B2 (en) * 2014-03-31 2019-02-05 Danmarks Tekniske Universitet Rotor for a pyrolysis centrifuge reactor

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