US769742A - Cement-kiln. - Google Patents

Description

No. 769,742. PATENTED SEPT. 13, 1904. F. M. HALDEMAN.

CEMENT KILN.

APPLICATION FILED PEB. 9.1904.

NO MODEL.

2 SHEETS-SHEET 1I Ilm/ENTER.

N0. 7691742. PTBNTED SEPT. 13, 1904, P. M. HALDBMAN.

CEMENT KILN APPLIGATION FILED TBB. 9.1904.

No MODEL. 2 slums-SHEET 2.

WTNESEEE. INVENTDR. 0f@ Mew/MJA @7M Mmm] JKM@ was@ UNITED STATES Patented September 13, 1904.

FRANK M. HALDEMAN, OF ALPENA, MICHIGAN.

CEMENT-KILN.

SPECIFICATION forming part of Letters Patent No. 769,742, dated September 13, 1904.

Application filer. February 9, 1904:. Serial No. 192,815. (No model.)

T0 all wtfmt it Wray concern.-

Be it known that I, FRANK M. HALDEMAN, a citizen of the United States, residing at Alpena, in the county of Alpena and State of Michigan, have .invented a certain new and useful Improvement in Cement-Kilns, of which the following' is a full, clear, and exact description, reference being had to the accompanying drawings.

In the operation of all cement-kilns with whose construction I am familiar there is a great loss of efficiency by reason of the cooling' down of the interior of the kiln or furnace through the admission of more air than is necessary to support combustion and by the carrying off by the draft of the finely-divided cement material fed into the end of the kiln which communicates with the smokestack.

The object of my invention is to correct the defects above noted, and the invention may be defined generally as consisting in the conibinations of elements set forth in the claims hereto annexed.

Referring to the drawings, Fig'ure l represents a broken side elevation of a furnace constructed in accordance with my invention, one end of the furnace and a portion of the stack being' shown in section. Fig'. 2 represents an enlarged cross-section of the furnace, said section being taken on the yline 2 2 of Fig. l, lthe cement-discharge door being open. Fig. 3 represents a central longitudinal section of the rear end of the furnace.

Describing the parts by letters, A represents the kiln proper, said kiln being of the inclined revolving type generally employed in manufacture of cement. The kiln may be provided with a circular rack B, driven by a pinion b, said pinion being driven in turn by the gears b' 12". The kiln is also provided with the customary antifriction-rollers C C and the circular anges C C, engaging said rollers. In kilns of this type with the construction of which I am familiar the rear or cementdischarging' end of the furnace is closed by a hood mounted on wheels, enabling' it to be placed in operative relation to the end of the furnace. rlhis hood is lined with fire-brick injector H for fine fuel.

or less air is admitted between the end of the furnace and the hood, materially lowering the temperature of the interior of the kiln. lVhen the furnace has been used for some time, the lower end of the same becomes more or less warped, thereby aggravating the original leakage of air at this point and making' it necessai-y to greatly increase the supply of fuel requisite to calcine or clinker the cement.

To overcome the difficulty above mentioned, I secure the hood to the body of the kiln, as shown in Figs. l and 3. The hood F. has a lining' e, of fire-brick or similar refractory material. The metal casing e of said hood extends considerably beyond said lining', enabling it to telescope over the metal casing a of the kiln proper, A. Near the end of the the hood-casing an angle-iron band e2 is provided, which encircles said casing and is riveted thereto. The casing of the kiln A carries a similar band fr', said band being so located that whcn the hood is in place the vertical flanges of said angle-irons are in close proximity to each other, enabling them to be secured together, as by bolts (t2. Between the fire-brick lining' a of the kiln proper and that of the hood is interposed a gasket (0*, of asbestos or similar non-heat-conducting and non-fusible material, the purpose of which is to prevent the fusing' or slagging together of said linings and to enable the hood to be easily removed from the kiln whenever desirable.

Another fruitful cause of impaired efliciency in furnaces of this type is the provision in the hood of a discharging-door for the cement, which door remains constantly open, thereby admitting an unnecessarily large amount of cold air. To obviate this defect, l have provided the kiln with a door D, which opens by gravity. l/Vith the door hinged, as shown in Fig. 2, and the furnace revolving in the direction of the arrow it will be apparent that the door will be closed during half of the revolution of the furnace and will be open when said door is brought into position to permit the discharge of cement therethrough. lVhile I have shown but one door, it will be evident that, if necessary, several such doors may be employed.

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As the natural tendency of the cement is to adhere to the interior of the kiln during the revolution of the latter, a considerable quantity of the cement which collects in the lower portion of the kiln will be carried up to a point at nearly ninety degrees from the lowest portion of the kiln. The door being open meanwhile permits the discharge of all such cement as may be in the corresponding belt of the kiln. To provide for the collection of a large proportion of the cement in said belt and to guide the cement to said door, Iprovide, preferably at the lowest end of the kiln A, below the door D, a wall of {ire-brick or similar material a5, which projects a considerable distance beyond the lining a3 of the kiln. Another wall, a, projects beyond such lining, though not so far beyond the same as the wall 60". This wall a is located in front of the door D. Between the walls a5 and a 'there is thus formed a channel which receives and retains the cement and guides the same to the discharge opening or openings. The natural tendency of the material to adhere to the wall or lining of the kiln as it rotates enables the discharge opening or openings to be effective for a considerable distance after they have been carried by the rotation of the furnace above the position shown in Fig. 2.

I have also found that in operation a considerable quantity of the finely-divided cement material whichis fed into the upper end of the kiln is carried away by the draft through the same. age of air at the bottom of the kiln, necessitating a corresponding increase in the supply vof pulverized fuel, the draft through the kiln is materially increased and a still larger amount of cement material iscarried away and lost.

By providing a bridge-wall for the upper end of the kiln and by feeding the cement material to the dead space formed adjacent to said wall I am enabled to protect the cement material while in its finely-divided condition from the influence of the draft and at the same time to permit the same to be elinkered or calcined before it reaches a portion of the kiln wherein it is exposed to the draft through the same.

F represents a stub-stack within which the upper end of the kiln projects. f represents a wall of said stub-stack adjacent to and supporting the upper end of the kiln. Adjacent to and forming a part of the wall f is a bridgewall f', which extends upward and across the end of the kiln a sufficient distance to throttle the draft and to provide a comparatively dead space extending from the top of the bridgewall a considerable distance down the kiln. The finely-powdered cement material may be fed by means of a hopper G and screw conveyer g through the wall f to the upper portion of the kiln. The finely-divided material being supplied to the dead space adjacent to With a considerable leakthe bridge-wall is not carried away by the draft and is subjected to. sufficient heat to clinker the same by the time it passes out of the dead space, at which time the danger of loss by being carried up the stack is passed.

From the foregoing description it will be apparent that I have produced a kiln which may be readily disassembled for repairs and in which there is no material loss of heatV by the introduction of unnecessary air nor loss of the cement-material due to the draft through the kiln.

While I have described ymy `invention-in detail, it is obvious that such details may be departed from more or less without departing from the spirit of my invention` and I do not propose to be limited by such details except as they may be included in the claims hereto annexed.

Vhat I claim as my invention, and desire to secure by Letters Patent, is-

l. A cement-kiln having a hood removably attached thereto, said hood and kiln being each provided with a lining of fire-brick or similar material, and a gasket of asbestos or similar non-heat-conducting and non-fusible material between said linings, substantially as described. l V

2. A cement-kiln consisting of a kiln portion proper and a hood portion, the kiln portion having a lining of fire-brick or similar material extending to the lower end of the same and the hood being provided with a similar lining, and a gasket of asbestos or similar non-heatconducting and non-fusible material interposed between the lining of the kiln and that of the hood, substantially as described.

3. Acement-kiln consisting of a kiln portion proper and a hood portion, the kiln portion comprising a casing and a lining of refractory material extending to the lower end of the casing, the hood comprising a casing having a refractory lining, the casing of the hood extending beyond its lining and adapted to telescope on the end of the kiln, and a gasket of non-heat-conducting and non-fusible material interposed between the end of the kiln and its lining and the lining of the hood, Substantially as described.

4. A rotary cement-kiln having near the lower end thereof a gravity-operated door and a channel adjacent to said door for retaining the cement material and supplying the same to the door, substantially as described.

5. A rotary cement-kiln having a refractory lining, an annular refractory wall at the lower end of said kiln projecting inwardly from said lining, asecond annular refractory wall spaced from the first wall and projecting inwardly a slightly smaller distance than the first wall, and a gravity-operated discharge-door for said kiln between saidwalls, substantially as described.

6. A rotary cement-kiln having at the lower end means for completely closing said end, an

loo

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inwardly-projecting annular wall within said kiln adjacent to said end, a second inwardlyprojecting wall spaced from the first-mentioned wall and projecting' into the kiln at slightly less distance than such first-mentioned wall, and a discharge-door between said walls, substantially as described.

7. A cement-kiln having, in combination, means for entirely closing the lower end of the same, a pipe for supplying fuel to the lower end of said kiln, said pipe extendingl through the closed end thereof, means for feeding cement material to the upper end of the kiln, and means for providing a dead space for said cement material adjacent to the upper end of said kiln, substantially as described.

8. A cement-kiln having, in combination, means for supplying fuel to the same, means for supplying finely-divided cement material to the same, and means for protecting' the cement material while in its finely-divided condition from the direct effects of the draft through the kiln, substantially as described.

9. An inclined cement-kiln having', in combination, means for supplyingfucl to the lower end thereof, means for introducing finely-divided cement material into the upper end of the same, and means located at the upper end of the kiln for protecting such material from the draft through the kiln, substantially as described.

l0. A kiln, having an inlet for fuel and an outlet for products of combustion, means for introducing finely-divided cement material into said kiln, and means adjacent to said outlet for protecting said material while in its finely divided condition from the draft through said kiln, substantially as described.

l1. A kiln for burning cement,said kiln having at one end an inlet for fuel and at the other end an outlet for products of combustion, a bridge-wall adjacent to the outlet end of the kiln, said bridge-wall closing the greater portion of said outlet, and means for introducing the cement material to said kiln at a point adjacent to the base of said bridge-wall, substantially as described.

12. A kiln for burning cement,said kiln having' at one end an inlet for fuel and at the other end an outlet for products of combustion, a bridge-wall extending nearly across the Outlet and closing the greater portion of the outlet, and means for introducing finely-divided cement material through said bridge-wall into the kiln, substantially as described.

13. A kiln for burning cement, said kiln having at one end means for introducing' pulverized fuel and at the other end a discharge-out let for products of combustion, a stub-stack with which the discharge end of said kiln communicates, a bridge-wall in said stack extending partly across and closely littingagainst the outlet from said kiln, and means for introducing finely-divided cement material to the kiln below the upper portion of said bridge-wall, substantially as described.

14. A cement-kiln having', in combination, means for supplying fuel thereto, means for supplying' cement material thereto, and means for forming' a dead space in said kiln adjacent to the point of introduction of the cement material, substantially as described.

l5. A cement-kiln consisting of a kiln portion proper and a hood portion, and a gasket of non-heat-conducting and non-fusible material interposed between said kiln portion and said hood portion, substantially as described.

In testimony whereof l hereunto aliix my signature in the presence of two witnesses.

FRANK M. HALDEMAN.

l/Vitnesses:

JOHN C. COMFORT, O. WV. BISHOP.

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