US1737704A - Agitator - Google Patents

Description

Dec. 3, 1929. E 'BQND AGITATOR Filed March 5, 1928 Patented Dec. 3,1929

UNITED STATES JOSEPH E. BOND, OF APIEETUN, WISCONSIN Application filed March 5, 1928. Serial No. 259,090. g

M invention relates to the art of paper making and particularly to means for agi tating paper pulp.

In the development of the 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 fluidity) of the pulp during its treatment preceding delivery to the Fourdriniers.

While in the old practice a 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 diflicult problems are encountered in 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 inherent 2 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.

, To avoid massing and stratifying of the pulp inthe liquid 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 the old practice the mixture was kept in motion by means of paddles 0r impellers in the tank, but this apparatus had very little tendency to break up masses of pulp, and was wholly ineflective with stock of increased density. Furthermore, such apparatus required an outlay of power not commensurate with the results secured.

The tanks, chests or containers which are in place and must be utilized for the new plan of operation are of many and varied forms, all of great size, some narrow and of great length, some deep and some round. The problem has been, therefore, to provide means applicable .to these various forms of tanks that, would insure efiective circulation, the breaking up of pulp masses and the maintenance at all times of a proper consistency throughout the whole volume of material, with a minimum of power expenditure.

The invention will be more readily understood by reierence to the accompanying drawings, in which- Fig. 1 is a plan view of a lay-out constructed'in accordance with my invention;

Fig. 2 is a side elevation thereof, and

Fig. 3 is an end elevation. In the drawings I have illustrated a charg-; mg chest or tank'approximately 8O feetin length and having side walls 10, 11 and end walls 12, 13. Extending longitudinally within the tank and substantially centrally-- thereof is a wall 14 dividing the tank into two compartments of substantially equal cross sectional area. At the ends of the wall,

14, I provide deflectors 15 which serve to. break up the currents and add to the agitating efi'e ct. l

Located exteriorly of the tank and at a; point substantially mid-way between its ends is a screw pump 16 preferably positioned at a level considerably below the floor of the chest. An inlet pipe 17 for the pump communicates with one of the compartments through the,

iloor of the tank and a discharge pipe 18 ex tends upwardly from the pump alongside of the tank and thence laterally to a point over the adjacent compartment.

The arrangement is such that with a quantity of pulp in the tank it is drawn into the pump and discharged upwardly and horizontally where it falls by gravity into the adjacent tank, both the inlet and discharge pipes being at a pointsubstantially midway of the 1 length of the chest.

Inasmuch as the two compartments are in communication at the ends of the division wall, the pulp is not only broken up, but is caused to flow in both directions from the motion and is agitated in a suitable manner at the time it passes through the screw pump. Obviously modifications may be made in the construction shown and I do not wish to be limited except as indicated in the appended claims.

I claim:

1. In combination, a relatively long narrow tank, a wall therein extending lengthwise thereof and dividing the space within the tank into two compartments in communication attheir ends, a pump located substantially midway between the ends of the tank and below the same, a pump inlet pipe connected to the bottom of one compartment and a pump outlet pipe discharging into the top of the other compartment.

2. In combination, a narrow tank, a longitudinal division wall terminating short of the ends of the tank and dividing the tank into two compartments in open communication at their ends, a pump midway between the ends of the tank and below the same, a pipe extending from a point near the bottom of one compartment to the pump inlet and a sec- 0nd pipe connected to the outlet from the pump and emptying into the top of the other compartment.

3. In combination, a long and narrow container, a longitudinal wall terminating short of the ends of the container and dividing the same into two compartments of substantially equal size, a pump having an inlet pipe connected to the bottom of one compartment and an outlet ipe connected to discharge into the top of the adjacent compartment, said inlet and outlet pipes being located substantially midway between the ends of the container.

4. In combination, a narrow tank, a longitudinal division wall terminating short of the ends of the tank and dividing the tank into two compartments in open communication at their ends, a pump midway between the ends of the tank and below the same, a pipe extending from a point near the bottom of one compartment to the pump inlet, and a ump outlet pipe extending upwardly alon 1de of the tank and over the top thereof an terminating above the second compartment.

In testimony whereof I have ailixed my signature.

JOSEPH E. BOND.

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