US1716298A - Agitator - Google Patents

Description

June 4, 1929. J. E. BOND 1,716,298

' AGITATOR Filed March 5, 1928 I Jar/en o Patented June 4, 1929.

FFICE.

JOSEPH E. BOND, OF APPLETON, WISCONSIN.

AGITA'I'OR.

Application filed March 5, 1928. Serial No. 259,089.

My invention relates to the art of paper making and particularly to means for ag1- tating paper pulp.

In the development of the art it has been found possible to greatly increase the capacity of a given equipment by 11'10163S1I1g the density (or, in other words, lessening the fluidity) of the pulp during its treatment preceding delivery to the Fourdrmiers. While in the old practice a 2 pulp was considered proper and of the maximum density possible, it is now common to deal w th 6% solutions, with correspondingly increased production capacity.

However, many difficult 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 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 in the 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 or impellers in the tank, 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 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 effective 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 reference to the accompanying drawings, in whi ch Fig. 1 is a plan view of a storage chest containing agitating means constructed in accordance with my invention, and

Fig. 2 is a longitudinal sectional view there-through on the line 22'of Fig. 1.

In the drawings I have illustrated a long and narrow tank or chest having side walls 10, 11, and end walls 12, 13. The tank is of a size to-contain approximately 175,000 gallons of paper stock and for this reason I have found it desirable to employ a circulating or agitating pump at each end of the tank. As a means for facilitating the circulation of the mass of'material Within the tank I provide a central longitudinally extending pair of baflle Walls 14, 15 extending inwardly from the end walls and terminating short of a meeting point, thereby leaving an open space 16 at the ends thereof. Preferably also I provide deflectors 17 on the ends of the bafiles 14, 15 for assisting in breaking up the currents of material. The construction of the baffle wall serves to form compartments A, B of substantially equal size located on opposite sides of the baffles.

At each end I provide pumps 18, 19 mounted in or projecting through the end walls 13, 12, the inlet openings for the pumps being in horizontal alignment therewith and communicating with a point near the floor of the tank. The inlet 18* for the pump 18 is at the bottom of tank B, while the inlet'19 for the pump 19 is at the bottom of tank A. Discharge pipes 20, 21 from the pump extend upwardly and laterally through the baflies 14, 15" withthe result that the discharge from the pump 18 is into the compartment A while the discharge from the pump 19 is into the compartment B. Preferably the pumps are of the screw type, the impeller of which is directly connected to a suitable motor as indicated.

In operation, the tanks being fully or partly filled with pulp and the pump motors in operation, liquid is drawn into the pumps from the lower level of one compartment and discharged into an adjacent compartment at a higher level, the travel of the liquid being substantially as indicated by the arrows in Fig. 1. Some of the liquid will pass directly from the outlet of one pump along the compartment in a straight line to the inlet of the opposite pump, while some other liquid may pass around the deflectors 17 through the opening 16 and back into the inlet of the pump from which it is discharged. A constant agitation and circulation is therefore assured.

Obviously the construction is capable of some modifications and I do not wish to be limited except as indicated in the appended claims.

I claim:

1. An agitator, comprising, in combination, a relatively long and narrow tank, a baffle wall extending longitudinally inwardly from each end wall of the tank and terminating at a point near the middle thereof with an open space therebetween, a pump at each end of the tank, the inlets of the pump being in communication with a low level in adjacent compartments formed by said baffle walls and the outlets from the pumps being in communication with a higher level of compartments opposite to those containing the inlets for the said pumps.

2. An agitator, comprising, in combination, arelatively long and narrow tank, a

baflle wall" extending longitudinally inwardy from each end wall of the tank and tion, a relatively long and narrow tank, a

baifie Wall extending longitudinally inwardly from each end Wall of the tank and terminating at a point near the middle thereof with an open space therebetween, thereby forming compartments A and B, a pump at one end having an inlet near the fioor of compartment A and an outlet near the top of compartment B, and a pump at the opposite end having an inlet near the bottom of compartment B and an outlet near the top of compartment A.

In testimony whereof I have afiixed my signature.

JOSEPH E. BOND.

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