US1028650A - Process of diffusion. - Google Patents

Description

P. J. WOLFE. PROCESS OF DIFFUSION.

APPLICATION FILED DBO. 24, 1910.

1 ,0285650, Patented June 4;, 1912.

' i'zg z. Fly 5.

vvvvvvvvvvv' PETER JACOB WOLFF, IBEDBURG, GERMANY.

PROCESS OF DIFFUSION.

Specification of Letters Patent.

Patented June 4, 1912.

Application filed December 24, 1910. Serial No. 599,146.

To all whom it may concern:

Be it known that I, PETER J ACOB WOLFF, a subject of the German Emperor, and resident of Bedburg, Germany, have invented a certain new and useful Process of Diffusion, of which the following is a specification.

Since the diffusion work has been introduced into the manufacture of sugar, it has been repeatedly proposed and tried with a view of extracting the juice by'dilfusion to .convey in a single diffusing apparatus beet-root chips and lixiviating liquid in a continuous manner and in opposite direc tions. Until the present time, however, the methods proposed have not given satisfactory results. Previously when chips were placed in the top of the diffusing apparatus and had to descend by gravity into the juice, it was found impossible to remove the exhausted chips in a suitable manner in addition to other difliculties which rendered a regular diffusion impossible. Again when the chips were conveyed in the opposite direction 2'. e. from below to the top, Archimedes screws, pistons and similar means were employed for forcing the beet-root chips with the necessary pressure into the diffusing apparatus. The chips were in which case either so strongly compressed that afterward they could notbe sufficiently loosened and distributed in the diffusing apparatus or a part of them was ground and crushed, or both, thus rendering the process impracticable. Likewise the stirring arms and screw blades, which were provided in the difiusing apparatus for causing the chips to advance compressed the chips strongly on the front surface while behind them the juice could pass freely without passing through the tighter layers. It sometimes happened also that chips remained stationary at some parts of the diffusing apparatus.

Now, the object of the present invention is to do away with the drawbacks cited above. This object is attained in the first place by forcing the chips into the diffusing apparatus not as formerly in a solid form but mixed with diffusion juice as afluid mass while the exhausted chipsespeoially when the chips are conveyed from the top to the bottomare flushed out of the diffusion apparatus by means of water or are forced out of the apparatus mixed with lixiviating water as a pulpy mass, the water after having been separated from the chips being returned to the diffusing apparatus. This method of working is new. In the process of diffusion as described in the French patent specification No. 401818, the ch1ps are it is true also mixed with hot juice but only in order to reheat them. Be-

chips before they are introduced into the diffusing apparatus with a view of rendering them soft and supple. In both cases the patentees had only the intention to introduce the chips in a solid form as is shown by the fact that the devices employed by them are absolutely unsuitable for forcing liquid substances into the diffusing apparatus.

I In the drawings: Figure 1 is a diagrammatic section of an apparatus for carrying out my improved method. Fig. 2 is a similar detail view of another form of structure for the bottom of the diffusing chamber. Fig. 3 is a similar view of a still further form of chamber bottom. Fig. 4 is a similar view of another form of bottom.- Fig. 5 is a diagrammatic section of a different form of apparatus for carrying out my improved method.

The diffusing apparatus a comprises a vertical cylindrical vessel-which is entirely open at its top' and has smooth inner surfaces. The funnel shaped sieve b has been mounted in the lower part of the vessel a. The latter is connected at its bottom end 0 by means of the pipe (Z (which in the drawing is positioned behind the diffusing apparatus) with the pressure receptacle 6 and may be separated from the latter through the medium of the valve f. The fresh chips fall directly from the chipping machine into the receptacle 6 and are mixed in the latter with such a quantity of juiceat thebeginning of the work with such a quantity of water-that a flowing mass is obtained. Or, the pulpy mass may be made up at any convenient place from chips and juice, and conveyed into the receptacle 2 by means of a channel and a pipe, or other suitable When it is desired to start the diffusing apparatus, the pulpy mass of chips is caused to flow from the pressure receptacle 6 into the cylinder (1. When the latter is filled up to half its height, the lixiviating operation is begun by withdrawing nice in a continuous manner at g and by causing water to enter continuously at the top at h. (The sieve 7: and the tubular extension Z are not employed for this operation.) Now, as the chip pulp enters continuously at a, the chips rise in the diffusing apparatus higher and higher and are finally flushed out through the upper open end of the diffusion vessel a by means of water as exhausted chips or are removed by any suitable mechanical device (scraper, drag, worm or the like). Before the water and the chips enter the diffusing apparatus, they are heated to suit the requirements.

The admission pipe may also pass through the center of the diffusing device. In this case it opens out at its bottom end above the sieve chamber as shown by Fig. 2 of the drawing.

In diffusing apparatuses of sieve construction Z), Fig. 1 having larger diameters it may happen that chips remain on the sieve permanently. This may be prevented by arranging the sieve of the diffusing apparatus not in the lower conical part of the latter but above it as for instance the sieve 7c in Fig. 1. The mixture of juice and chips is thus forced to be distributed over the en tire cross section of the diffusing apparatus before it reaches the sieve and yields its juice.

In the form of embodiment as shown by Fig. 3 a flat iron wound in a helicoidal manner and connected by means of horizontal arms wit-h a vertical shaft, rotates in the sieve chamber and continuously scrapes the chips from the sieve, causing them to rise.

A very good means for conveniently distributing and conveying the chips is also afforded by the grate shown by Fig. I and which forms the upper limit of the lower conical part of the difiusing apparatus. The combined slots of this grate do not exceed in area that of the inlet pipe for the chip pulp. The chips are thus obliged,

when passing into the cylindrical part of the diffusing apparatus to utilize entirely all the slots of the grate and to push forward the column of chips which is above them by exerting the same pressure at all places. In order to prevent the chips from remaining on the grate bars, the latter have such a shape, that their cross section forms an elongated vertical triangle.

Inthe' processes described heretofore the feed of the diffusing apparatus takes place without any interruption. It is however more advantageous not to introduce the chips in a continuous manner but regularly from time to time in larger quantities and to withdraw the juice during the intervals between the different charges. In this case, the chips introduced last unite themselves each time after the charging operation is finished with the chips which were already in the diffusing apparatus and form a coherent, non-liqu1d mass, which at the next charging operation is pushed upward as a whole like a large plug.

In order to prevent during the intervals between the different feeding operations, the chips from settling down too much in the piping through which the mixture of chip and juice is introduced from below into the apparatus, a part of the fresh diffusion juice orif the piping has a very large diameter-the entire juice is conveyed through the said piping from below to the top. The diffusion then already begins in the said piping, which thus becomes so to speak a diffusing apparatus.

(The chip pulp may also be stored up in a collector provided at the bottom of the diffusing apparatus and be forced from the said collector into the diffusing apparatus by means of compressed air or steam).

The method just described may be carried out in the simple device shown by Fig. 1 by causing the juice to escape tl'irough Z when the chips are introduced, and through 9 at other times. The process may be carried out better by means of the diffusing apparatus shown by Fig. 5. In fact, this apparatus allows the lixiviation under high pressure as already mentioned and is also provided with a device for causing the chips to advance regularly in the diffusing apparatus, this device being, it is true not so simple as that described above but working with more reliability. This diffusing apparatus is provided at the top and at the bottom with two openings n, 0, p and g' which may be closed by means of throttle valves. Water coming from an elevated reservoir enters at n and the exhausted chips are forced out through 0. The juice escapes at- 9 and the chips are introduced into the apparatus through 9. At the bottom, the an nular sieve 1- forms together with the enlarged sieve mouth the juice collecting chamber 8. Provided in the sieve chamber is a grating 25 made of round iron bar and framed in a fiat iron ring which applies itself to the sieve 1'. The grating is secured to the rod 1 and may be raised and lowered shaft 00 and may at the same time be raised and lowered. Fig. 5 shows the device in the position which it occupies when juice is drawn off. The water flows in at the top at n and escapes below at p as juice. The admission and escape openings for the chips are closed. The grating 25 occupies its lowermost position. In the top part of the difi'using apparatus, the chips are loosened by the rake w and form with the water a fluid mass. When it is desired to introduce chips into the diffusing apparatus, the openings n and p are closed and those 9 and 0 are opened. The pressure exerted by the entering chip pulp raises then the entire contents of the apparatus and the upper part of said contents is forced out through 0. The grating t also rises as it is pressed from below against the rising column of chips. The latter is thus held together and the sieve r is cleaned at the same time. The rake w is also raised by the rising column of chips, but penetrates at the same time deeper and deeper into it and loosens the upper layer of chips for the next following escape of chips. When the grating t has reached the upper edge of the sieve, it is rapidly pulled down again through the chip pulp until it reaches the lower edge of the sieve. During this motion, a rotary mot-ion may be imparted to the grating so as to thoroughly clean it from the chips which might adhere thereto. The opening 0 is then closed and p opened. The chip pulp which still continues arriving through the grating 25, then forces the juice through the sieve out of the diffusing apparatus until finally the entire sieve chamber is crammed with chips. If the passage 9 is then closed and the passage 01. opened, the water entering the vessel under pressure penetrates into the chips from the top toward the bottom as in an ordinary diffusing apparatus and escapes at p as fresh difiusing juice. From 79 this fresh juice descends entirely or partly into the feed pipe for the chips, rises slowly in this feed pipe, preventing the settling down of the chips, and escapes through the sieve at z. The juice which escapes through 10 during the feeding operation is directly carried off by the duct y. When the quantity of juice corresponding to the quantity of chips in troduced has been drawn off, the difl'using apparatus receives a fresh charge and work is continued in the manner described above.

The stop devices for the chip pulp are provided with a secured perforated closing flap positioned in advance of the closing flap proper, the said perforated flap being closed first and thus allowing only liquid to pass. This liquid washes the closing flap which may then be easily and tightly closed.

The process and the device according to the present invention maybe employed, and

this is needless to say, for lixiviating other materials.

The extraction of juice according to the present invention has the following advantages in comparison with the ordinary process of diffusion: 1.No waste water is produced. 2.-All the component parts of the beet-roots are extracted without any loss as juice and exhausted chips. 3.The diffusing apparatus and the chip press may be connected together in such a manner by means of pipes that the water used for carrying the chips away and the water resulting from the pressing operation are brought back into the diffusing apparatus without coming into contact with the surrounding air. 4.Loss of juice produced by leaky valves or wrongly adjusted valves, which often occur in ordinary difl'usionwork, are entirely prevented. 5.The device and the process are very simple and cheap. All that is necessary is to control the march of the work from time to time according to the results of the analysis o-fthe exhausted chips or press water.

Having now fully described my said invention, what I claim and desire to secure by Letters Patent, is:

The process of extracting juice from beet chips by lixiviation in which the diffusion juice and the chips travel in opposite directions, consisting in making a fluid mixture of the chips and diffusion juice, forming a vertical column composed of such mixture, feeding water to the. upper part of the column Withdrawing the extract of juice from the lower end of the column feeding fresh portions of the mixture of chips and diffusion juice to the column from below and withdrawing the exhausted chips from the top of the column as they are forced upward by the entering mixture.

In testimony whereof I have hereunto set my hand in presence of two witnesses.

PETER JACOB WOLFF.

Witnesses:

LOUIS VANDORY, GERTRUD BONA.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). C.

Images