US450750A - Process of manufacturing hydraulic cement - Google Patents

Description

UNITED STATES PATENT OFFICE.

JAMES l3. SPEED, OELOUISVILLE, KENTUCKY.

PROCESS OF MANUFACTURING HYDRAULIC CEMEN T.

SPECIFICATION forming part of Letters Patent No. 450,750, dated April 21, 1891.

Application filed February 11, 1891. Serial No. 881,075. (No specimens.)

To all whom it may concern:

Be it known that I, JAMES B. SPEED, of Louisville, county of Jefferson, State of Kentucky, a citizen of the United States, have invented an Improved Process of Manufacturing Hydraulic Cement, of which the following is a full, clear, and exact specification.

My invention relates to improvements in the process of manufacturing hydraulic cement; and the object of my invention is to secure an economy both in the fuel required for calcining the cement-rock and in the time occupied in the operation of burning, as Well as a uniformity in the cement product.

My invention consists in first reducing the blocks of rock as they come from the quarry to lumps or pieces of varying sizes, then separating such lumps or pieces into groups in which, respectively, the lumps are of approximately uniform size, then charging the several said groups of rock-lumps individually into the kiln with fuel, and finally firing the kiln, substantially as and for the purpose hereinafter set forth.

In carrying out my improved process the rock as it comes from the quarry in the form of large blocks is first reduced to lumps or pieces of comparatively small dimensions and of varying sizes. This may be accomplished by passing the quarried rock-blocks through a stone-breaker. l he pieces of broken rock as they come from the stone-breaker are then separated into groups in which, respectively, the rock-lumps composing said groups are of approximately uniform size. This may be done by passing the broken rock over successive screens which have respectively meshes of various sizes, so that the smaller pieces of rock of approximately uniform size will pass through and fall beneath one screen. The pieces of somewhatlarger and approximately uniform dimensions will pass through and fall beneath another screen, and so on until the largest pieces, approximately of uniform size, will be discharged as tailings from the final screen of the series. The respective groups of lumps, said lumps being, as stated, of substantially uniform size in the said re spective groups, are then charged severally and individually into the kiln with the fuel. The respective groups of lumps may be charged severally into separate kilns, so that each kiln may contain as its entire charge lumps of approximately uniform size throughout mingled with the requisite fuel, or the said groups may be charged successively individually into one and the same kiln, each group having supplied to it its requisite fuel, so that such kiln will have as a chargegroups of lumps of uniform size in successive layers. It is obvious that in supplying fuel to the kiln or kilns with the said respective groups of lumps the larger lumps will require a larger proportion of fuel than the smaller lumps in charging. The kilns are then fired, and the operation of calcining the rock may be carried on in the well-known vertical kilns and which may be those that work on the single charge or continuous burning plans.

Any other known means than a stone-breaking machine may be employed to effect the reduction of the quarry-blocks of rock to small lumps or pieces, and any other known means than screens may be used to separate the broken rock into groups in which, respectively, the lumps are of approximately uniform size. The means described are named solely because they are believed to be preferable.

lleretofore in calcining cement-rock in kilns the rock in irregular-sized lumps or blocks has been indiscriminately charged into the kilns, so thateach kiln contained a charge composed of rock pieces of varying sizes mingled with the fuel either in alternate layers or heterogeneously. The calcining under these conditions has of necessity been ununiformand the product obtained varying in quality.

By means of my described method, the broken cement rock being separated into groups of approximately uniform-sized pieces, respectively, the charge of each kiln of a se ries thereof or the successive charges of a single kiln will be composed of rock-lumps of substantially uniform size, and hence will be uniformly calcined, and also the quantity of fuel required and the period of time demanded to efiect the calcining of each group of uniform-sized rock-lumps may be closely predetermined, thus effecting an economyin both the fuel and the time of operation.

I am aware'that in the preparation of cement-rock for calcining the rock has been reduced by crushing into pieces of such a fineness that the rock has been approximately pulverized and so that the largest of such pieces did not exceed in dimensions a certain predetermined size, and that the thus-crushed rock has been then charged directly from the crusher into a furnace, in which it was in its pulverulent condition calcined. I make no claim herein to such treatment of cementrock in its preparation for calcining, and such treatment of the rock is not analogous either in operation or result to my herein-described process. This is plainly obvious in that even in crushing the rock to a fineness which renders it substantially pulverulent the result will be that while pieces will be produced the largest of which will not exceed in dimensions a certain predetermined size, it will necessarily follow that somein fact, the larger portion-of the rock-pieces in the crushed mass will be of a less dimension than the predetermined size fixed upon for the pieces of greatest dimensions, and hence the resultant mass of crushed rock will be composed of pieces which, though all of comparatively small dimensions, will be of varying sizes, and these pieces of Varying sizes being charged directly and heterogeneously into a furnace the disadvantages sought to be obviated by my described improved process will accrue in the resultant cement. In my improved process, as herein described and to which I limit my claim herein, the rock is reduced, as by breaking, to lumps or pieces of varying sizes, and these lumps are separated, as bya series of screens, into groups in which, respectively, the lumps are of approximately uniform size, and these groups of uniformsized lumps are charged individually and severally into the kiln.

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

The process of manufacturing hydraulic cement, which consists in first reducing the blocks of rock as they come from the quarry to lumps or pieces of varying sizes, then separating such lumps or pieces of rock into groups wherein, respectively, the lumps are of approximately uniformsize, then charging the several said groups of rock-lumps separately into the kiln with the fuel, and finally firing the kiln, substantially as and for the purpose set forth.

JAMES B. SPEED.

WVitnesses:

A. S. FITCH, A. T. FALES.