US776186A - Calcining-furnace. - Google Patents

Calcining-furnace. Download PDF

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US776186A
US776186A US19055204A US1904190552A US776186A US 776186 A US776186 A US 776186A US 19055204 A US19055204 A US 19055204A US 1904190552 A US1904190552 A US 1904190552A US 776186 A US776186 A US 776186A
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flue
chamber
calcining
flues
furnace
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William A Koeneman
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27BFURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B1/00Shaft or like vertical or substantially vertical furnaces
    • F27B1/10Details, accessories, or equipment peculiar to furnaces of these types
    • F27B1/20Arrangements of devices for charging

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  • My invention relates to improvement in calcining-furnaces generally and more especially to a furnace for dehydrating gypsum or plaster rocks and earths in the production of commercial plasterof-paris.
  • My object is to provide a furnace of generally improved construction, adapting it for calcining crushed gypsum rock or the like and dehydrating more especially the gypsum constituent of the mass.
  • Figure l is a partly-sectional elevation of my improved furnace, the section being taken on line 1 in Fig.
  • FIG. 2 Fig. 2, a section taken on line 2 in Figs. 1 and 4; Fig. 3, a broken section taken on line 3 in Fig. 4; Fig. 4, a plan section taken on line 4 in Fig. 3;---Figs. 5, v6, and 7', enlarged broken perspective views showing the construction of cross-fines in the furnace for'conducting the heating-gases, distributing air, and carrying off vapor; Fig. 8, an enlarged broken section taken on line 8 in Fig. 2; and Fig. 9, an enlarged broken sectional view at an end of one set of fines.
  • a B are what may "be considered the outer side walls of the furnace,and C D the end walls.
  • - E F are inner walls or diaphragms, which may be of boiler-plate and forming with the walls A B the flue-spaces G H.
  • I I are series of horizontally-extending fines, fastened at opposite ends in the plates or diaphragms E F.
  • the series may be disposed as shown in Figs. 2 and 3, whereby they intermesh with the series above and below them.
  • Each fine I is formed, as shown in Fig. 7, with parallel sides a a, inclined shoulder portions 6 5, reduced top 0, and longitudinally-extending partition (Z.
  • the partition d divides the floor into an upper gas-channel e and lower vapor-channel f.
  • a floor or horizontal partition K which separates the said fluespaces from pits G H.
  • I have shown a fire-chamber L at the side of the wall B, having an outlet-flue L leading to the flue H at the floor K.
  • Extending across the flue-space H in the position shown is a horizontal diaphragm H and extending across the flue-space G is a horizontal diaphragm G
  • the channels 0 open at opposite ends into the flue-spaces Gr H; but the channels f are each closed at one end, those beneath the diaphragm H being closed to the flue-space H and open to the flue-space Gr, those above the diaphragm H being closed to the flue-space Gr and open to the flue-space H, and those above the diaphragm G being closed to the flue-space H and open to the flue-space G.
  • Hot products of combustion rising from the fire-chamberL through the flue L are discharged into the flue-space H beneath the diaphragm H and pass through the plurality of gas-flues c to the flue-space G. From the flue-space G beneath the diaphragm G the gases pass through the plurality of gas-flues e to the flue-space H above the diaphragm H and from thence they pass through the upper gas-flues e to the fluespace G above the diaphragm G and thence out at the chimney M.
  • the said hot products of combustion pursue a Zigzag course, first through the lower sets of gasflues, then backward through the next overlying or intermediate gas-flues, and finally through the upper gas-flues.
  • the vapor-abstracting conduits or channelsf are closed at the inlet ends of the flues 0, so that the hot products of combustion from the fire-chamber do not pass through them.
  • each flue I represents air conducting and distributing flues extending longitudinally across each of the flues I.
  • Each flue I extends from the outer side of the wall B through the plate or diaphragm F and terminates at the plate or diaphragm E.
  • Each flue I where it crosses the flue-space H is closed on four sides; but between the plates or diaphragms F E it is open along its under side and fits over the top 0 of the underlying flue I, as shown in Figs. 3 and 5, leaving narrow air-outlet spaces or slots g between their lower edges and the inclined shoulders 5.
  • a skeleton frame P resting between guide-blocks 7a, which permit vertical movement of the frame.
  • the frame consists of outer angle-bars t', stretching around its four sides, and parallel series of cross-extending rods or pipes t".
  • a series of vertical rods or pipes 71 Depending from each rod or pipe '2" is a series of vertical rods or pipes 71;, each provided with a plurality of projecting pins or fingers Z, as indicated.
  • the rods 2" are fastened upon the frame P toward opposite ends, and one is provided centrally above each vertical space between adjacent flues I.
  • the hoppers R extend entirely across the calciningchamber from the partition E to the partition F, and each is closed at its lower open end by a cylinder S, formed at one side with a longitudinally-extending pocket S, as shown in Fig. 3.
  • the cylinders S are upon shafts S each provided at one end in the pit G with a ratchetwheel S
  • Above the series of ratchet-wheels S in the pit G is a horizontally-extending bar T, supported between guide-rollers S* and extending through the wall D, beyond which it is pivotally connected between the ends of an operating-lever T.
  • a pawl T Beneath the discharging-cylinders S is a pit containing a discharge-hopper V, provided in its base with a discharging-conveyer V.
  • the calcining chamber is charged through the top with gypsum rock or the like, which fills the vertical spaces above the cylinders S between the adjacent flues I and I.
  • the products of combustion or gases from the fire-chamber L pass through the flues or channels 6, as described, and heat the surrounding mass of gypsum without mixing therewith.
  • the frame P is moved up and down to cause the pin-carrying bars 7:: to agitate the mass.
  • the vapor eliminated therefrom passes upward into the channels f and is conducted to the flue-spaces at the discharge ends of the gas-flues 6.
  • the discharge-cylinders S may be rotated by working the lever T, so that the pockets S will be turned first into the filling position and then into discharging position to withdraw in each revolution a pocket full of the calcined material and discharge it into the hopper V.
  • the bar T or equivalent discharge-operating mechanism may be actuated from a suitable engine or motor, so that the material may be withdrawn as fast as the calcining operation progresses.
  • Automatic charging means may be provided for maintaining the chamber filled with the raw material; but this forms no part of the present invention.
  • the smoke-flue thereof IIO may connect with the flue L and waste products of combustion be thus employed either I admission flues may likewise be dispensed with.
  • apparatus for calcining gypsum, or the like the combination of a furnace, a calciningchamber, a plurality of heat-radiating flues communicating at one end with the said furnace, to conduct the hot products of combustion therefrom, and crossing sa1d chamber, a series of vapor-abstracting condults crossing and open to said chamber, and means for feeding the material to be calcined against and past the sides of said flues and conduits, the said flues being all closed to said calciningchamber whereby the said material is kept from physical contact with the hot products of combustion from the furnace during the entire calcining operation.
  • afurnace for calcining gypsum or the like, the combination of a calcining-chamber, flue-spaces at, opposite sides of said chamber, a plurality of heat conducting and radiating flues extending across said chamber and communicating at opposite ends with said fluespaces, one said flue-space communicating at its lower end with the supply of the heating medium and one said flue-space having an outlet for said medium toward its upper end, diaphragms in the flue-spaces operating to direct said heating medium in a Zigzag course through said flues and flue-spaces, and air supplying and distributing and vapor-abstracting conduits opening into said chamber and extending parallel with said flues to the outside of the chamber, a feed-opening for the material to be treated toward the upper end of said chamber and a discharge-opening for said material at the lower part of said chamber, substantially as and for the purpose set forth.
  • a calcining-chamber provided at its upper end with a feed-opening for the material to be treated and at its lower end with a dischargeopening for said material, a plurality of heat conducting and radiating flues extending across said chamber and arranged in vertical series with vertical spaces between them through which the material to be calcined may descend by gravity, a corresponding plurality of air supplying and distributing conduits, and a corresponding plurality of vapor-abstracting conduits, the said conduits being arranged in vertical line with said flues above and below the latter, and being in open communication with the interior of the chamber and extending to the outside of the latter, substantially as and for the purpose set forth.
  • a calcining-chamber provided at its upper end with a feed-opening for the material to be calcined and at its lower end with a discharge-opening therefor, a plurality of sets of heat-conducting flues, and vapor-abstracting conduits, arranged in vertical series with vertical spaces between them through which the material to be calcined may descend by gravity, agitating means for the material comprising a frame mounted above the chamber and having series of depending rods, in each of said vertical spaces, and means for moving said frame, substantially as and for the purpose set forth.
  • a furnace for calcining gypsum, or the like the combination of a calcining-chamber, and a plurality of sets of heat-conducting flues and air-distributing and vapor-abstracting conduits extending across said chamber, and arranged in vertical series with spaces between them through which the material to be calcined may descend by gravity, said sets comprising each a central heat-conducting flue, ranged to operate, substantially as and for the closed to said chamber, a conduit for vaplor purpose set forth. beneath said flue and open throughout to t 1e chamber and extending to the outside thereof, WILLIAM KONEMAN' and a conduit above said flue communicating In presence of with the outside air and open throughout its F. M. WIRTZ,

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)

Description

No. 776,186. PATENTED NOV. 29, 1904. W. A. KUNEMAN.
GALGINING FURNACE.
APPLIUATION FILE-D JAN. 25, 1904.
N0 MODEL- 5 SHEETS-8113B? 1.
PA'TBNTED NOV. 29, 1904.
W. A. KUNEMAN. CALGINING FURNACE.
APPLICATION TILED JAN. 25, 1904.
5 SHEETS-SHEET 2.
N0 MODEL.
mwmww No. 776.186. PATENTED' NOV. 29, 1904.
W. A. KUNEMAN. GALGINING FURNACE.
APPLIUATION FILED JAN. 25, 1904.
N0 MODEL. 5 SHEETS-SHEET 3.
I Y fizz/6722 077 A I 4 7 V No. 776,186. PATENTED NOV. 29, 1904.
' W. A. KUNEMAN. GALGINING FURNACE.
APPLICATION FILED JAK. 25, 1904.
NO MODEL. 5 SHEETFr-SHEET 4.
N0. 776,186. PATENTED NOV. 29, 1904. W. A. KONEMAN.
CALCINING FURNACE. APPLIGATIONTILED JAN. 25, 1904.
5 S HTS-SHEET 5.
N0 MODEL.
' UNITED STATES Patented November 29, 1904.
PATENT OFFICE.
CALClNlNG-FURNAGE.
SPECIFICATION forming part of Letters Patent No. 776,186, dated November 29, 1904.
Application filed January 25, 1904:. Serial No. 190,552. (No model.)
To aZZ whom, it may concern:
Be it known that I, VVLLLIAM A. KONEMAN, a citizen of the United States, residing at Ohicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in calcining-Furnaces, of which the following is a specification.
My invention relates to improvement in calcining-furnaces generally and more especially to a furnace for dehydrating gypsum or plaster rocks and earths in the production of commercial plasterof-paris.
In a separate concurrent application for Letters Patent filed by me December 28, 1903, and bearing Serial No. 186,909, I have described an improved method of producing plaster-of-paris, of which one of the steps consists in subjecting the raw material, usually gypsum rock, in a crushed state, to heat which will dehydrate the gypsum constituent and leave other constituents, such as bone rock, in a relatively harder condition, whereby a final disintegration of the mass may be readily eflected in a manner to pulverize the gypsum to a finer mesh than the other constituents and permit it to be sifted olf and saved.
My object is to provide a furnace of generally improved construction, adapting it for calcining crushed gypsum rock or the like and dehydrating more especially the gypsum constituent of the mass.
It is further my object to provide such a furnace wherein the mass may be fed by gravity and suitably agitated to subject it throughout to the action of the heat without its being contaminated by hot products of combustion, means being also provided for conducting air into the mass and for carrying off vapor, and it is still further my object to provide a calcining-furnace of comparatively simple and inexpensive construction which in its operation will be economical in the use of fuel and require but little. attendant labor and which will be particularly well adapted for the purpose of dehydrating the gypsum in large quantities rapidly and effectively.
Referring to the drawings, Figure l is a partly-sectional elevation of my improved furnace, the section being taken on line 1 in Fig.
2; Fig. 2, a section taken on line 2 in Figs. 1 and 4; Fig. 3, a broken section taken on line 3 in Fig. 4; Fig. 4, a plan section taken on line 4 in Fig. 3;---Figs. 5, v6, and 7', enlarged broken perspective views showing the construction of cross-fines in the furnace for'conducting the heating-gases, distributing air, and carrying off vapor; Fig. 8, an enlarged broken section taken on line 8 in Fig. 2; and Fig. 9, an enlarged broken sectional view at an end of one set of fines.
A B are what may "be considered the outer side walls of the furnace,and C D the end walls.
- E F are inner walls or diaphragms, which may be of boiler-plate and forming with the walls A B the flue-spaces G H.
I I are series of horizontally-extending fines, fastened at opposite ends in the plates or diaphragms E F. The series may be disposed as shown in Figs. 2 and 3, whereby they intermesh with the series above and below them. Each fine I is formed, as shown in Fig. 7, with parallel sides a a, inclined shoulder portions 6 5, reduced top 0, and longitudinally-extending partition (Z. The partition d divides the floor into an upper gas-channel e and lower vapor-channel f.
Extending across the base of the flue-space G and base of the flue-space H, at the level indicated in Fig. 2, is a floor or horizontal partition K, which separates the said fluespaces from pits G H. In the drawings I have shown a fire-chamber L at the side of the wall B, having an outlet-flue L leading to the flue H at the floor K. Extending across the flue-space H in the position shown is a horizontal diaphragm H and extending across the flue-space G is a horizontal diaphragm G The channels 0 open at opposite ends into the flue-spaces Gr H; but the channels f are each closed at one end, those beneath the diaphragm H being closed to the flue-space H and open to the flue-space Gr, those above the diaphragm H being closed to the flue-space Gr and open to the flue-space H, and those above the diaphragm G being closed to the flue-space H and open to the flue-space G. Hot products of combustion rising from the fire-chamberL through the flue L are discharged into the flue-space H beneath the diaphragm H and pass through the plurality of gas-flues c to the flue-space G. From the flue-space G beneath the diaphragm G the gases pass through the plurality of gas-flues e to the flue-space H above the diaphragm H and from thence they pass through the upper gas-flues e to the fluespace G above the diaphragm G and thence out at the chimney M. Thus the said hot products of combustion pursue a Zigzag course, first through the lower sets of gasflues, then backward through the next overlying or intermediate gas-flues, and finally through the upper gas-flues. The vapor-abstracting conduits or channelsf are closed at the inlet ends of the flues 0, so that the hot products of combustion from the fire-chamber do not pass through them.
I represents air conducting and distributing flues extending longitudinally across each of the flues I. Each flue I extends from the outer side of the wall B through the plate or diaphragm F and terminates at the plate or diaphragm E. Each flue I where it crosses the flue-space H is closed on four sides; but between the plates or diaphragms F E it is open along its under side and fits over the top 0 of the underlying flue I, as shown in Figs. 3 and 5, leaving narrow air-outlet spaces or slots g between their lower edges and the inclined shoulders 5.
The space bounded by the walls O D and diaphragms EF forms the calcining-chamber N. On the top of this structure and covering the chamber N is a skeleton frame P, resting between guide-blocks 7a, which permit vertical movement of the frame. The frame consists of outer angle-bars t', stretching around its four sides, and parallel series of cross-extending rods or pipes t". Depending from each rod or pipe '2" is a series of vertical rods or pipes 71;, each provided with a plurality of projecting pins or fingers Z, as indicated. The rods 2" are fastened upon the frame P toward opposite ends, and one is provided centrally above each vertical space between adjacent flues I. In each such space there is a series of downward-extending rods L, as indicated in Fig. 2. Rods '5, toward opposite edges of the frame P, project past the furnace-walls A B and are there connected by links at with arms 92., keyed to a fulcrum-shaft 1], extending entirely through the furnace and journaled in suitable bearings in the walls A B. The arm N at one end of the furnace is the short arm of a bell-crank lever Q, the long arm of which is connected, by means of a link (1, with an operating-lever 0' at that end of the furnace, as shown in Fig. 1. By swinging the lever a an operator may rock the shaft 32 and raise and lower the frame F in the guides it, whereby the rods or agitators 71; are moved up and down. The lower part of the chamber N is separated into a series of hoppers R,
the sides of the hoppers terminating at their upper ends centrally beneath the lower flues I, as shown in Fig. 3. The hoppers R extend entirely across the calciningchamber from the partition E to the partition F, and each is closed at its lower open end by a cylinder S, formed at one side with a longitudinally-extending pocket S, as shown in Fig. 3. The cylinders S are upon shafts S each provided at one end in the pit G with a ratchetwheel S Above the series of ratchet-wheels S in the pit G is a horizontally-extending bar T, supported between guide-rollers S* and extending through the wall D, beyond which it is pivotally connected between the ends of an operating-lever T. On the bar T at each ratchet-wheel S is a pawl T Beneath the discharging-cylinders S is a pit containing a discharge-hopper V, provided in its base with a discharging-conveyer V.
In operation the calcining chamber is charged through the top with gypsum rock or the like, which fills the vertical spaces above the cylinders S between the adjacent flues I and I. The products of combustion or gases from the fire-chamber L pass through the flues or channels 6, as described, and heat the surrounding mass of gypsum without mixing therewith. At regular intervals or occasionally, as required, the frame P is moved up and down to cause the pin-carrying bars 7:: to agitate the mass. During dehydration of the mass the vapor eliminated therefrom passes upward into the channels f and is conducted to the flue-spaces at the discharge ends of the gas-flues 6. Outside air is drawn through the flues I and discharged into the mass through the slots 9 to facilitate the dehydrating operation. The discharge-cylinders S may be rotated by working the lever T, so that the pockets S will be turned first into the filling position and then into discharging position to withdraw in each revolution a pocket full of the calcined material and discharge it into the hopper V. Instead of providing a hand-lever T, as shown, the bar T or equivalent discharge-operating mechanism may be actuated from a suitable engine or motor, so that the material may be withdrawn as fast as the calcining operation progresses. I prefer to maintain in the calcining-chamber a temperature equal to about 400 Fahrenheit, and taking into consideration the height of the calciningchamber and the length of time required to calcine the particular material being treated the discharge mechanism may be actuated to properly time the calcining operation. Automatic charging means may be provided for maintaining the chamber filled with the raw material; but this forms no part of the present invention.
Where my improved calcining furnace forms part of or is erected adjacent to a boilerfurnace or the like, the smoke-flue thereof IIO may connect with the flue L and waste products of combustion be thus employed either I admission flues may likewise be dispensed with.
What I claim as new, and desire to secure by Letters Patent, is-
1. In apparatus for calcining gypsum, or the like, the combination of a furnace, a calciningchamber, a plurality of heat-radiating flues communicating at one end with the said furnace, to conduct the hot products of combustion therefrom, and crossing sa1d chamber, a series of vapor-abstracting condults crossing and open to said chamber, and means for feeding the material to be calcined against and past the sides of said flues and conduits, the said flues being all closed to said calciningchamber whereby the said material is kept from physical contact with the hot products of combustion from the furnace during the entire calcining operation.
2. In apparatus for calcining gypsum, without subjecting the material to be calcined to physical contact with hot products of combustion, the combination with the calcining-chamber and with a combustion-chamber, of a plurality of heat-radiating flues crossing, and all closed to, said calcining-chamber and com municating at one end with the supply of hot products of combustion from said combustionchamber and at the other end with an outlet series of vapor-abstracting conduits crossing and open to said chamber, the said flues and conduits being arranged in a plurality of vertical series with spaces between the series, means for feeding the material to be calcined through said spaces against and past the sides of said flues and conduits, and agitating means for the material in said spaces, said flues being all closed to said calcining-chamber whereby the said material is kept from physical contact with the hot products of combustion from the furnace during the entire calcining operation.
4. In afurnace for calcining gypsum, or the like, the combination of a calcining-chamber, flue-spaces at, opposite sides of said chamber, a plurality of heat conducting and radiating flues extending across said chamber and communicating at opposite ends with said fluespaces, one said flue-space communicating at its lower end with the supply of the heating medium and one said flue-space having an outlet for said medium toward its upper end, diaphragms in the flue-spaces operating to direct said heating medium in a Zigzag course through said flues and flue-spaces, and air supplying and distributing and vapor-abstracting conduits opening into said chamber and extending parallel with said flues to the outside of the chamber, a feed-opening for the material to be treated toward the upper end of said chamber and a discharge-opening for said material at the lower part of said chamber, substantially as and for the purpose set forth.
5. In a furnace for calcining gypsum, or the like, a calcining-chamber provided at its upper end with a feed-opening for the material to be treated and at its lower end with a dischargeopening for said material, a plurality of heat conducting and radiating flues extending across said chamber and arranged in vertical series with vertical spaces between them through which the material to be calcined may descend by gravity, a corresponding plurality of air supplying and distributing conduits, and a corresponding plurality of vapor-abstracting conduits, the said conduits being arranged in vertical line with said flues above and below the latter, and being in open communication with the interior of the chamber and extending to the outside of the latter, substantially as and for the purpose set forth.
6. In a furnace for calcining gypsum, or the like, the combination of a calcining-chamber provided at its upper end with a feed-opening for the material to be calcined and at its lower end with a discharge-opening therefor, a plurality of sets of heat-conducting flues, and vapor-abstracting conduits, arranged in vertical series with vertical spaces between them through which the material to be calcined may descend by gravity, agitating means for the material comprising a frame mounted above the chamber and having series of depending rods, in each of said vertical spaces, and means for moving said frame, substantially as and for the purpose set forth.
7. In a furnace for calcining gypsum, or the like, the combination of a calcining-chamber, and a plurality of sets of heat-conducting flues and air-distributing and vapor-abstracting conduits extending across said chamber, and arranged in vertical series with spaces between them through which the material to be calcined may descend by gravity, said sets comprising each a central heat-conducting flue, ranged to operate, substantially as and for the closed to said chamber, a conduit for vaplor purpose set forth. beneath said flue and open throughout to t 1e chamber and extending to the outside thereof, WILLIAM KONEMAN' and a conduit above said flue communicating In presence of with the outside air and open throughout its F. M. WIRTZ,
length in said chamber, all constructed and ar- WV. B. DAVIES.
US19055204A 1904-01-25 1904-01-25 Calcining-furnace. Expired - Lifetime US776186A (en)

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