US1737703A - Agitator - Google Patents

Description

J. E. BOND Dec. 3, 1929.

AGITATOR l Filed Maron 5, 192a Patented Dec. 3, A1929 narran' STATES yJ'OSIEEH E. BOND, OF APPLETON, WISCONSIN AGITATOB Application led March 5,

My invention relates to the art of paper making and particularly to means for agitatin paper pulp.

n the development ofthe art it has been found possible to greatly increase the capacity of a given equipment by increasing the density (or, in other words, lessening the diuidity) of the pulp during its treatment preceding delivery to the Fourdriniers. While in the old practice a 21/2% pulp was considered proper and of the maximum density possible, it is now common to deal with 6% solutions, with correspondingly increased production capacity.

However, many diiiicult problems are en- 'countered 1n handling pulp of this density due to its lack of fluidity and its tendency to mass or cake in the storage or treatment tanks and containers. -This tendency is in` 20, herent in the nature of the material under treatment due to its fibrous character and to the physical law of attraction of solids. The liquid within which the solids are carried serves merely as a supporting medium therefor and facilitates rather than hinders the massing and intertwining of the fibers. v

To avoid massing and stratifying of the pulp in the liqud and to maintain a uniform density throughout the entire body of material it must be kept in motion and the motion producing means should have a tendency to break up and tear apart any large or small masses of pulp. In theold practice the mixture was kept in motion b means of paddles or impellers in the tan but this apparatus had very little tendency to break up masses of pulp, and was wholly ineffective with stock of increased density. Furthermore, such apparatus required an outlay of e0 power not commensurate with the results secured.

rIhe tanks, chests or containers which are in place and must be utilized for the new lan lof operation are of many andvaried orms, all of great size, some narrow and of the breaking up of pulp masses and the main- 1928. serial No. 259,086.

tenance at all times of a proper consistency and then discharging it at a plurality of points at a different level from that of the intake. This of necessity compels a breaking up of the solids, insures constant motion and prevents stratification.

The invention will be more readily understood by reference to the accompanying drawing, in which- Fig. 1 is a plan view of an agitator arranged in accordance with my invention, and

Fig. 2 is a longitudinal sectional view therethrough.

In the drawing, l haveillustrated a tank usually about 70 feet in length, the walls of which are constructed of concrete. The tank comprises a floor, l0, side walls 11, and end walls 12, 13. At the bottom and at one end as well as-at the vertical corners of the walls I provide large fillets which serve to facilitate the circulation of the liquid within the tank.

A screw pump 14 is mounted within the end wall 12, it being operated by means of a motor y15. An inlet pipe 16 is located at a point close to the floor 10, while the outlet pipe 17 projects upwardly from the pump, nconnects to an elbow 18and lto a long pipe 19, extending longitudinally of the tank at the middle and near the top thereof. The pipe 19 terminates in a T 2O by means of which the liquid discharged through the pipe is caused to be directed oppositely at a point near the upper level of the pulp.

The pump being in operation and a quantity of pulp being placed in the tank, it is drawn into the inlet pipe, through the pump and thence outwardly along the pipe 19fto the discharge end thereof at the extremity of the tank. This results in a continuous and effective circulation of the liquid preventing stratification and serving to prevent cohesion of the pulp articles.

One of the principal forces tending to disintegrate and prevent cohesion of the fibrous pulp particles is that of the screw pump, the

action of the blades of the propeller of which tends to agitate and disseminate the particles throughout the liquid carried. A similar action is not secured by any other form of ump.

Obviously the exact form and arrangement may be changed within limits without departure from the spirit of my invention.

I claim:

1. In combination, a 'relatively long and narrow horizontally disposed tank, a pump at one end thereof, said pump having an inlet at the bottom of the tank, and a pump discharge pipe extending longitudinally and substantially the entire length of the tank ending near the top of the tank. 2. In combination, a relatively long and Y narrow horizontally disposed tank, a pump y at one end thereof, said pump having' an inzo let at the bottom of the tank, and a pump discharge pipe extending longitudinally and substantially the entire length of the tank ending in a plurality of lateral outlets.

3. In an agitator, the combination with a zs ve long and narrow horizontally disposed taiik, of a pump located at one end of the tank, and having an inlet at substantially the level of the bottom of the tank," and a conduit connected to the discharge from the pump, said conduit extending substantially the en tire length of the tank and Within the same and having its outlet at'a point near the top of the tank.

4. In an agitator, the combination With a very long and narrow horizontally disposed tank, of a pump located at one end of the tank, and having an inlet at substantially the level of the bottom of the tank, and a conduit A connected to the discharge from the pump, 40 said conduit extending substantially the entire length ofthe tank and Within the same and having a plurality of outlets at the ar end of the tank near the top thereof.

In testimony whereof. I have affixed my signature. Y

- JOSEPH E. BOND.

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