US1917505A - Method of hydrating cellulose fibers - Google Patents

Description

y 1933- 'J. A. DE cEw 1,917,505

METHOD 0F HYDRATING CELLULOSE FIBERS Filed Nov. 23, 1929 1 N I "EN TOR.

inns UN FLDE DEW.

BY 3 E ATTORNEY.

Patented July 11, 1933 UNITED STATES TENT OFFICE.

JUDSON A. DE CEW, OF MOUNT VERNON, NEW YORK, ASSIGNOQR TO PROCESS ENGINEERS,

INC 01 NEW YORK, N. Y., A OORPORATION OF NEW YORK monor nvnnnrmo cnnnunosn rmnns' Application filed November 23, 1929. Serial No. 409,213.

In the refining and hydration of paper making fibers by means of ordan engines, refiners, and machines of similar type, it is the common practice in the mills having more 5 than one Jordan to a paper machine, to pass the pulp directly from one Jordan through another or through several similar machines.

many as eight of these machines may be set up in tandem and the stock allowed to pass through them all before it is considered ready for the paper machine.

I have invented an improved method of treating the paper stock with these machines and herewith disclose why an improved result is obtained.

When a raw unhydrated, or partially hydrated, cellulose fiber is fed into a Jordan engine or other hydratin machines, it is in -much more viscous condltion than when it comes from the machine, for the treatment softens the fibers so that they then flow more readily with the same amount of water and the stock appears thinner.

The stock entering the machines flows slowly and pumps with difficulty. There is, therefore, a limit to the density of stock that may enter the first machine under given conditions, which is lower than the density that would enter the second machine under similar conditions after the stock has passed first through the Jordan, refiner or hydrator.

My invention comprises removing a portion of the water from the stock after it has passed through one or more J ordans or machines of the Jordan type and then passing it through further machines, and repeating this practiceuntil the treatment is finished. There are two main advantages in this process: one is that by constantly thickening the stock as it is being treated, the friction amongst the fibers is increased and less power is r uired by the machines. Another distinct a vantage is the cooling of the stock. As the ulp stock gets hot the rate of hydration is decreased and the stock becomes freer, and when the stock is forced through direct- 1y connected J ordans the temperature often rises as high as 150 E, which is too hot to obtain either the best degree of hydration 50 or the results.

ity in order to work very coarse stock and By removing portions of water from the stock. as it is being jordaned, or similarly treated and repeating this operation in different stages, the temperature is not increased to the same extent, as the stock cools during the thickening process, which is only possible by intermittent operation. I

In Figure 1 I show a pipe from a head box feeding the Jordan 10, as shown in my U; S. Patent N 0. 1,598,267. A portion of the water is then removed from the stock by means of a washer, drainer, or any other water-extracting device, 11.

In the next step I show the stock being pumped through the Jordan type engine 12 asdescribed in my U. S. Patent N 0. 1,7 04,533, and then more water removed at 13 and finally,after possibly one or more additional similar stepsthe operation where the stock is washed and dewatered at 14.

Both of the above-mentioned patents contemplate treating the stock at high density but by different means, but do not disclose this principle of extracting water after a refining operation, which process will increase the efficiency obtained by either of the patented methods.

By this new process it is also quite feasible to Jordan or refine the stock. first at low denkeep thickening it as the refining action takes place. After each step in the process the fibers come closer to each other, and the vis cosity of the pulp mass is maintained so that the work done by the'last Jordan is equal 8 to that of those preceding it. If this process is not used and the stock is forced through a series of J ordans or hydrators, then the friction of the stock within the machine is constantly decreasing with each succeeding treatment.

Another application of this process is to add cooling water to the washers during the thickening operation, which washes and cools the stock. This is preferably applied in the latter operations. This washing operation can also be applied to remove impuri ties from the stock.

This process may be carried out in another manner, as disclosed diagrammatically in 100 and operated by the batch method and the same rocess carried out by pumping the stock ack into the beater. In this way'the same result would be obtained as beating the stock for a long time and then passing the stock through successive jordaning and thickening operations.

There are in use several types of machines containing revolving discs with smooth or ribbed surfaces which are called hydrators .or refiners, which all have a resemblance to the Jordan type machine. The general term for these is refiner, although they could also be described as Jordan type machines. Any of these machines could be used as a iubstltute for the Jordan in using my inven- Various methods may be used to increase the density of the stock between refining operations. In Fig. 1, I show a thickening device consisting of a tank which has a drainer bottom above the bottom of the tank, and by means of a controlled outlet a portion of the water is drained away before the stock is pumped to the next refiner. Any other form of thickening may be used to increase the density during a break in the jordaning .or hydrating process.

The type of hydrator may be changed during these operations; thus the stock might first be passed through a Marshall engine and later through a Jordan and finally through one of the revolving disc machines. Between these operations the stock may be thickened by any de-watering process.

It is to be understood that the present dis;

closure is for the purpose of illustration only, and that the invention is not limited thereto. To those skilled in the art, many modifications of the invention will be readily apparent, and it will also be obvious to such skilled persons that part of the method and means may be used without other parts thereof, many such combinations of the parts readily suggesting themselves. Therefore, it should be and is to be distinctly under stood that for a definition ofthelimitationg of the inventionjreferenc inust be had to the appended claims.

Having now described the invention, what is claimed as new and for which Letters Patent of the United States is desired, is:

1. A method of treating cellulose fibers by a plurality of Jordan type refiningmachines,

which comprises partially 'de-watering the pulp after the first refining operation, and

before the last refining operation.

2. A method of treating paper making fibers by means of Jordan type refining machines, which consists in increasing the density of the pulp after a previous jordaning operation has reduced its viscosity.

3. A method of preparing paper stock with a plurality of Jordan type refining machines, which consists in refining at a progressively heavier consistency.

4. A method of treating paper pulp by means of a plurality of Jordan type refining machines, which consists in maintaining a practically constant viscosity of the pulp for each refining operation, by de-watering the pulp as the viscosity decreases.

5. A method of refining paper stock which consists in thickening the stock intermediate of the refining operations.

Signed at New York, in the county of New York, and State of New York, this 22nd day of November, 1929.

JUDSON A. DE OEW.

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