US54510A - Improved apparatus for the manufacture of paper-pulp - Google Patents

Description

JOHN W. DIXON AND GEORGE HABDING, OF PHILADELPHIA, PA.

IMPROVED APPARATUS FORATHE MANUFACTURE OF PAPER-PULP.

Specification forming part of Letters Patent N0. al, dated May 8, 1866.

reference being had to the annexed drawing,

making a part of this specification, in whichrepresents a strong digester, capableof resistmg heavy pressure. B is alower perforated diaphragm, having a passage, O, for the escape of the pulp. Below B is a space, E n', for they accumulation of the liquid. The passage O is closed by a valve at D or at F, except when the pulp is to escape.

In this particular apparatus the digester is shown as heated by fire placed below the digester, although all of the improvements herein described, except one combination, could be used with any otherform of heating apparatus. A circulating tube passes from below the diaphragm B to the upper part of the digester. In the course of this tube a rotary or reciproeatin g pump, I-I, is placed. This pump is to be driven by machinery, andproduces a constant circulation of the digestingliquid from the lower chamber, E, below the diaphragm, through G, into the upper part of the digester, or, vice versa, from the upper part of the chamber down through tube G and the pump into the bottom of the digester, and thence upl land opening cock 3 the pump can be made to wardly, by virtue of the force of the pump, through the mass to be pulped. When it is desired to withdraw the pulp the valves Dand F may be both opened and the material permitted to escape directly on the valve. D may be first opened, and the material permitted to pass into the tubular space or passage between D and F, and then, when the valve D is closed and the valve F opened, the material between D and F will escape.

In order to facilitate the withdrawal of the valve D and prevent the pulp from escaping with too great a shock a small steam-pipe extends from the upper part of the digester into the space between D and F, and by opening the cock 1 the pressure on both sides of D is put in equilibrium. This cock is to be closed before F is opened. In this way a portion of the contents can be quietly withdrawn at any time while thepulpingoperationis still goin gon,

Theoperation of the apparatus is as follows: The wood, straw, or other material, in a nely divided state, is to be introduced through the man-hole at the .top of the digester A. A solution of caustic soda, or lime, or water alone, or other digestingliquid, is to be introduced, and when the digester is closed up heat is to be applied below to the bottom of the digester, and the pump started, the cocks 2 being open `and cocks l Iand 3 closed. The pump may be operated so as to force the liquid from below B through G into the top of the digester, whence it would descend through the material being pulped, or the pumps may be used to force the heated liquor vice versathat is, up through the diaphragm B and through the mass being pulped to the top of the digester, whence it would descend outside through G again into the pump and the bottom of the di gester. p

Fresh material may be introduced while the operation is going on by opening the valve K and introducing the charge of wood, &c., between the valve K and valve L. `The valve K is then to be closed and the valve L opened, when the charge falls by its own gravity into the boiler.

In order to relieve the valves of pressure from the inside we employ the tube p, when the cock 4 places the space between K and L in equilibrium with the digester by causing steam to pass between K and L.

By opening the cock l and closing cock 2 force fresh water or liquid into the bottom ofthe digester from a heating apparatus, T, or tank T, (such as described in a former patent of J. W. Dixon,) where it becomes heated, and then up through the material, and the refuse liquid could pass through cock 3 into the coil U U U U, and thus heats the incoming liquid entering through cock 1 in the manner fully described in other patents heretofore granted to us. The introduction of fresh water belowV into the digester, in combination with the introduction of fresh charges of material above, would cause the fresher water always to bein 4contact with the most nished pulp.

So far as relates to the subject-matter of the five first claims, herein after set forth, any other mode of heating thecirculating liquid might be adopted, such as an exterior boiler or coil or a coil within the main digester.

Having thus described our improvement, what we claim as our invention, and desire to secure by Letters Patent, isi 1. rlhe pulp-digester,in combination with a lower perforated diaphragm having a central pulp-passage, a circulating tube or tubes connectin g the upperandlower part ofthe digester.

2. The pulp-digester, iu combination with a lower perforated diaphragm, a central pulppassage, a circulating tube and pump, to produce a circulation through the mass from bottom to top, or vice versa.

3. The two valves D and F in the pulp-escape tube, for withdrawing a portion of the contents without interfering with the operation within the digester.

4. The charging-pipe S, with its double;

valves, for introducing fresh material without disturbing the operation.

5. The combination of pulp-digester, circulating tube, and pump, when the fire is applied directly beneath the digester.

6. The continual forcing in of fresh liquid below and upward through the mass to be pulped, in combination with the introduction of the fresh charges of the material into the digester above, whereby the cleaner liquid would always be in contact with the pulp most cooked.

JOHN W. DIXON. GEORGE HARDING.

Witnesses:

GEORGE BUGKLEY, BENJN. MOMAKIN, Jr.

Images