US36048A - Improved apparatus for leaching tan-bark and obtaining extracts - Google Patents

Description

'vided with my invention.

UNITED STATES PATENT OFFICE.

' WILLIAM II. ALLEN, OF FRYEBURG, MAINE, ASSIGNOR TO I-IIMSELF AND OTIS IVARREN, OF SAME PLACE.

Specification forming part of Letters Patent No. 36,048, dated July 29, 1862.

` To @ZZ whom it may concern:

specication and represented in the accompanying drawings, of which-` Figure lis a top view, and Fig. 2 a vertical and transverse section, of a leaching-vat pro- Fig. 3 is a horizontal and longitudinal section of the perforated distributing arm or tube, to be hereinafter described.

The purpose of my invention is to distribute water or any other leaching-liquid in line streams and evenly on the upper surface of a mass of bark or other material to be leached.

My invention is specially adapted for extracting tannin from bark, but is equally applicable to leaching wood-ashes for the purpose of obtaining an alkaline lye therefrom.

. In carrying out my invention I employ a tub or vat, A, furnished with a perforated false bottom or strainer, B, which in the drawings is exhibited as elevated somewhat above the real bottom a, in order that there may be a liquor-receiving space, b, between the two.

From the central part of the bottom a a post, c, rises vertically and receives on its top and gives support to the closed lower end of a rotary tubular shaft, O, whoseupper end is open and extends into a stuffing-box, d, xed on the lower end of a chambered conduit-elbow, D. The said elbow is fastened tothe side of a crossbar, E, which is supported by two standards, F F, and is extended over the vat, as shown in the drawings.

A horizontal shaft, G, is sustained by a box, g, and a hanger, h, arranged with respect to the tub or vat, as shown in Figs. l and 2. A driving-pulley, i, is fixed on the outer end of the shaft, while a beveled pinion or gear, 7c, is attached to the inner end of such shaft and engages with another beveled gear, Z, fixed on vthe tubular shaft C.

A hollow or chambered arm, G', extends horizontally from the shaft O, opens into it, is closed at its outer end, and along one side is provided with a series of openings, m m m m, etc. These openings are arranged at equal distances apart, and as they vary in their distances from the center of the shaft C are increased in size,their areas being to one another in the proportions of the circumferences of their circles of revolution, or thereabout, in order that each hole, while the machine may bein action, may discharge a like amount of liquid on a like extent of surface traversed by it-that is to say, if we suppose the first hole of the series to be situated at any given distance from the axis of the vertical shaft C, and the third hole to be twice that distance from such axis, it will be evident that during each entire revolution of the shaft C tho said third hole will pass over twice the surface that the first hole does, 'and consequently should discharge twice the amount ot'liquid that may be thrown out of the y iirst,it being supposed that the pressure within the shaft Gis constant, and also that the delivery to the two holes is not materially impeded by friction. rlhe ratio ofthe sizes, therefore, of the several holes will be very nearly that of the circumferences of circles in which they travel, due allowance being made for friction.

In the process of leaching bark it has been customary to pour the water indiscriminately over the surface of the mass, or allow it to stand in a large quantity on the same. Under these circumstances so rapid a percolation or infiltration of the liquid takes place as to produce a very imperfect extraction of the tannin. The purpose of my invention is -to induce a slow and even percolation of the fluid through the mass of the bark, and I accomplish this by suffering hot water to run into the shaft C and from thence into the arm G and out of its perforations while the said arm and shaft are in revolution together, so as to cause the arm to pass over the upper surface of a mass of ground bark should be numerous and as near as possible at I claim y equal distances apart, in order that the dis- My improved leaching apparatus, concharge of the liquid from the lower surface of structed in manner and so to operate, substam the mass of bark upheld by the strainer may tially as represented and described.

be uniform. Y The even infiltration of the liquid into and WM' H' ALLEN its even discharge from, the muss of berk is Witnesses: e matter of necessity in order to obtain the IsAIM-r WARREN, best or most thorough extraction of the tannin. ASA CHARLES.

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