US2206237A - Affination apparatus for treating sugar - Google Patents

Description

July 2, 1940'. E. ROBERTS AFFINATIOS APPARATUS FOR TREATING SUGAR Filed June 5.,V 1936 l 2 Sheets-Sheet 1 July 2, 1940. E. ROBERTS l 2,206,237

AFFINATION APPARATUS FOR TREATING SUGAR Filed June 5, 193s l 2 sheets-sheet 2 J9 LH ifm/W Mrz@ Patented July 2, 1940 Eugene neuem, mating. N. Y., signor to The Western' States Machine Company, Salt Lake City, Utah, a corporation of Utah Application June 5, 1936,- Serlal No. 83,634

8 Claims.

This invention relates especially to the art of refining raw cane sugar and is intended to provide an apparatus for efficiently and economically carrying out an improved process of producing a mixture or magma of raw sugar and syrup properly conditioned foi` eiective centrifuging.

Prior to the invention of the improved Stevens aillnation process describedin a copending application, Serial No. 151,772, filed July 3, 1937, which 1o is a continuation-impart of an earlier applicai tion, Serial No. 68,013-,illed March 10, 1936, the magma was generally produced byvmixing together streams of unsaturated heated syrup and I of raw or unrened sugar, and the condition of l5 the magma supplied to the centrifugalsy depended wholly upon the carefulness and judgment of the attendant operator. Variations in the ratio of syrup to sugar were inevitable so that magma being-delivered to the centrifugals from time to time varied -greatly in respect to the ratio of syrup to sugar content and in respect 'to viscosity of the magma, thus preventing uniformity y of centrifuging. Under the Stevens amnation process the magma is formed by mixing the raw sugar with a very small proportion of hotsyrup in a substantially saturated condition to form a heavy, non-flowing mass. and this mass during passage to the centrifugals is heated without dilution or addition to its bulk to about the initial temperature of the hot saturated syrup, and is delivered in the resulting fluid condition to the centrifugal separators.

Even under the practice of the above described Stevens process the ratio of syrup content to the dry content in the magma is likely to vary somewhat from time to time, thus making it difficult to'maintain the maximum eiliciency of the process.

The present invention increases eiiiciency if 40 .not already present at this point provid-ing a selfregulating apparatus by which uniformity of consistency is obtained in the magma delivered tothe centrifugals therefore avoiding either an excess or a deficiency in the -syrup content of the magma. It also provides an improved ailination content, while at the same time greatly economizing in the cost of carrying out the ailination process, since the apparatus can operate, after being v started, -under its own regulation without depending upon the faulty regulation occasioned 5 by lack of skill or negligence on the part of the attendant. 'Ihe adjustments for a given run of sugar can be made by an expert supervisor to produce exactly the optimum conditioning of the magma being centrifuged.

In said drawings Fig. 1 illustrates a partly diagrammatic arrangement of the' improved amnation apparatus forming the subject of this invention.

Fig. 2 is a detail view in front elevation, partly l5 in section, showing the magma heating stirrer coils by which the magma is heated to reduce its viscosity without dilution, so that it will readily build up in the centrifugal basket when it is in process of, being centrifuged, both for separation '20 or extraction of the syrup from the sugar and' for centrifugal washing to remove the adherent iilm or coating containing by far the greater part of the impurities associated with lthe sugar crystals or grains.

Fig. `3 is a front elevation in central section showing means for evenly distributing the measuredsupply of magma for delivery to the hot mingler.

Fig. 4 is a transverse section of the apparatus 30 shown in Fig. 3 illustrating the relation of the distributing scroll to the underneath hot mingler.

In the drawings there is provideda usual storage receptacle or tank I provided with openingsv along the inclined bottom portion, as shown at 2, 35 that are covered by inclined shutters 3. 'I'he convergent bottom of thetank forms a contracted nomic or outlet close to which are located a pair of revoluble feedjrolls 6 and 1. One of these feed rolls 6 is journaled in slidable bearing boxes -40 t, which are normally spring pressedI to their innermost limit of movement but which permit yielding of the roll to allow vany hardmatter, such as a stone or piece of iron, to pass between the rolls without injury. The opposing roll 1 is 45 journaled in slidable bearing boxes 1 which are provided with connecting rods 8, which is under the control of a regulating means, such as a solenoid il, 4the movement of whose plunger controis, in this case, the position of adjustment of the roll l by means of a bell crank arm 9, 9* and a coacting spring Il in a manner presently to be described.

Beneath the gap between the feed rolls t and l is preferably placed a horizontal magnetiled bar ,f

.go through the mesh of the screen or sifter. 'I'he raw sugar being delivered by the feed rolls falls in a stream upon the vibratory sifter I3, which is suspended at one end by means of pivotal links I4 and whose other end is supported upon a revoluble eccentric cam I5 to'impart the desired vibratory or shaking movement to the sieve. The sugar dropping through the sieve4 falls upon a travelling conveyor orl belt 25. ,This belt travels around a drum 22 upon the shaft 2| which is mounted in fixedl bearings and the outer end of the belt orconveyor passes around the drum 24, which is mounted in a frame 2|) fulcrumed coaxially of the shaft 2|. This frame is yieldingly supported by a scale spring 26 or its equivalent, which is tensioned so that when there is'no load upon the conveyor belt the frame 20 swings according to the quantity of sugar resting upon it, the frame drops to lower positions. Near the offtake end of the conveyor is supported a gauge l5, which is horizontally adjustable by means of an adjusting nut I1, so that the forwardor right hand end of the gauge will be located to various positions in advance of the fulcral axis at 2|. When the frame swings to its uppermost position' the conveyor belt is close beneath the front member of the gauge I6 and little or no sugar can be carried bythe gauge, which acts as a scraper to level the stream of sugar carried by the conveyor to uniform thickness, so that the conveyor is delivering a predetermined quantity of sugar which is subject to increase by the dropping of the conveyor belt as the sugar load increases and which is diminished as the conveyor belt or frame 20 rises toward the gauge. A liquid supply pipe 40 delivers through its nozzle at the bottom a spray of syrup,'the volume of said syrup being controlled by the regulating valve 4| which, in this case, is shown as of the plunger type, whose shank is connected with a bell crank arm 42, which in turn is connected with the frame 2B of the belt conveyor by means of a connecting link 43. 'Ihe arrangement is such that as the belt rises under a diminishing load the plunger valve 4| is pushed inwardly toward its seat to correspondingly diminish the flow of the syrup. On thefother hand, when the frame 20 drops under an increasing load. on the conveyor the valve is opened wider to correspondingly increase the' flow of liquid. In this way there is provided a self-regulating coordination between the supply o! syrup and the supply of sugar with which it mixed with the dry material so that the ratio of dry material to syrup is automatically maintained.

The link 4|* connecting the valve 4| with the,

rials and the resulting heavy mixture is delivered through an opening in the bottom ofthe mixing trough 50 into the hot mingler trough 53 which has a converging partition providing a' delivery lslot or nozzle, whose opening is regulated by means of a pivotal, adjustable valve 54. A downward extension 55 of the mingler trough, of narrow proportions forms the nal mixing and heating chamber in which the heating of the heavy mixture toa temperature approximately equal to the initial temperature of the hot syrup supplied by the pipe 40 is effected and a magma possessing optimum characteristics for centrifuging is obtained. The preliminary heating, in this case, is effected by a tubular stirrer 56 comprising helical coils mounted on, and communicating with, a central hollow shaft 51 through which a large volume of hot water is circulated through the helical coils, so that the surrounding body of magma is simultaneously stirred and heated. A

similar heating and stirring coil 56 is mounted in the bottom extension from which lead the goosenecks or discharge spouts 58, one for each centrifugal of the battery.

-nearly saturated condition so that the mixture delivered to the hot mingler trough of the centrifugal apparatus may be of a much higher Brix or percent, 'dry substance than would be possible were it not subjected to a reheating. Furthermore,r if a saturated hot syrup be used there is little ifany dissolving of the sugar grains by the hot syrup. This method of reheating is not my invention, but the apparatus by which the mixing of the raw sugar and syrup is effectively controlled and regulated and the mixture is conducted to the centrifugals forms the subject matter of thepresent invention. The centrifugal machine 59 may be of any suitable gyratory suspension type, but the best results will be eiected by the use of centrifugal driving means which 'are capable of bringing the machine from a state of rest to a speed of approximately 1500 revolutions in substantiallyless than one minute.

For the most part it is intended that the flow of magma from the mixing trough 50 shall correspond approximately to the capacity ofthe battery of centrifugal machines forming part of the apparatus, but as one or more of the battery of centrifugals may temporarily be shut down for repairs or temporary treatment While the remainder of the centrifugals are kept in operation todispose of the supply of magma, provision has been made to prevent the magma from overflowing the hot mingler trough 53 on the one hand, or from reaching too low a level therein on the other hand. This is effected by means of a float gauge 50 which acts to close or to interrupt electric control circuits by which the feeding of the material to the mixing trough 5D is accomplished or regulated.

It will be understood that the width of the space between the delivery rolls 6 and 1 determines the rate of supply or the quantity of dry material fed into the mixing trough 50. To give complete exibility to the adjustment'of the roller 1, the bell crank lever 9 has one arm 9'L that is angularly adjustable about its rock shaft and is held in desired position of adjustment by a set screw Sb in its hub, so that the adjustment does not alter the position of its horizontal arm to the actuating plunger of the solenoid Ill. The slidable bearing box 1 isnormally retracted by a spring Il to a position that is determined by the adjustment of 75 a stop member, such for example as an eccentric cam 9a arranged back of the arm S". The cam 8* may be set so that when the solenoid is actuated it will close the gap between the forward rollers 1 and 8, or so that it will leave as narrow a gap between the rollers as may bedes'ired.

Obviously, provisions may be made to narrow or the adjustments above described.

This control may be utilized for various purposes. In the drawings I have made provision against' overloading the conveyor belt 25 and to prevent overflow of the magma in the hot mingler trough 53. To accomplish these objects the solenoid circuit x is provided with terminal contacts a and b, which are closed by the contact member c secured to a oat 60 arranged so that the solenoid circuit is closed by the lifting of the 'float when it reaches a level substantially below the level of the top of the hot mingler trough 53. To prevent overloading of the conveyor belt 25, a movable terminal contact member e is carried by the scale beam frame 20 normally spaced some distance above the fixed companion terminal f.

'Should there be an excessive accumulation of material in front of the adjustable gauge I6, the scale-beam or frame 20 drops far enough to establish contact between e and f which are in a shunt circuit y leading to the solenoid I0. By this or equivalent arrangement the overflowing of the hot mingler trough and the overloading of the conveyor belt is prevented. This is especially desirable when one or more of the centriiugals forming the battery supplied from the hot mingler are for the time being out of commission so that a decrease in the supply of material being fed from the storage tank is effected.

To keep the dry material in the bottom of the feed trough I broken up so as to readily pass between the feed rollers, there is provided a series of stirrer rods which are given a combined rocking and reciprocating movement by means of a revolving eccentric 10 encircled by a head to which the fingers or arms 12 are attached.

The feed rolls, the sifter and the conveyor apron 25, as well as the mixing scroll 5| are driven by means of an electric motor 30 having driving connection with suitable gearing and clutch mechanism mounted on the countershaft 33 from which by belts or otherwise power is transmitted to the different parts of the mechanism. Since any suitable or well known driving arrangement serving this purpose may be used, particular details of construction and arrangement of this part of the mechanism is omitted.

Where only three or four centrifugals are supplied from the same hot mingler the magma, discharged from the end of the mixing trough into the middle portion of the hot mingler trough, will be sufficiently distributed for practical-purposes but with an arrangement of apparatusv having a larger number of centrifugals in a row the hot mingler will have a correspondingly greater length and therefore an intermediate distributor is preferably used, as shown in Fig. 3 and Fig. i. With such arrangement, the scrollcmtaining mixer trough 50, at its discharge end, lrops the stream of magma into an intermediate ,distributing trough 10 located on top ofvthevhot mingler and in parallelism therewith and there.

is located in the bottom portion of the distributor trough a revoluble conveyor having reversely turned scrolls 1| extending, respectively, from the middle to the ends of the trough 10. 'I'he distributor trough 10 is mounted directly on thel top 12 of the hot mingler trough 13 and at suitable intervals along the bottom there are provided vopenings 14 in the distributing trough and nally heated heat-transferring and stirrer coilsv 56 to the bottom of the trough 13, whence it is distributed through separate discharge chutes'58 to the individual centrifugals 59 in a suiiiciently fluent condition to permit its being suiliciently and rapidly centrifuged.

In Fig. 3 is also shown the make-up ltank 65 which was omitted from Fig. 1 because of lack of space and which is provided with a steam supply or reheating pipe 66 and into which leads the return pipe 59, which returns the hot water that was pumped successively through the coils by means of the pumph 61 and the lead-in pipe 51 which forms the revolving support for the coil.

What I claim is:

1. In an amnation apparatus of the class described, the combination of a sugar supply bin openl at its bottom, coacting spaced feed rolls located at the bottom outlet of said trough, a

lvibrating sieve located beneath said feed rollers,

a travelling conveyor beneath said sieve for re- `ceiving and deliveringI a regulated stream of sugar, said conveyor being supported on a pivoted scale beam, a gauge member located above said travelling conveyor forwardly of the pivotal axis of the scale beam and coacting with said pivotall'y mounted conveyor to vary the quantity delivered in accordance with variations in the quantity delivered by said feed rollers, a valved liquid supply pipe, and means for maintaining at uniform ratio the quantities of sugar and of liquid supplied to a mixing trough, and means fo'r mixing the sugar-and liquid to a uniform consistency before conveying the mixture to the cen trifugal apparatus.

2. In an apparatus of the type described the combination with a sugar supply chute, a pair of spaced feed rolls arranged beneath the outlet of said chute, a pivotally supported travelling conveyor belt mounted to receive the sugar delivered by said feed rolls, an adjustable gauge member located above said conveyor and coacting therewith to regulate the quantity of sugar delivered by the conveyor, a liquidsupply pipe provided with a regulating v alve, and means con necting the pivotal conveyor with said valve to coordinate variations in the supply of sugar with corresponding variations in the supply of liquid, and means for mixing to a uniform consstency the regulated supplies of sugar and liquid.

3. In an apparatus of the class described, the

combination with a mixing trough, containing a member, said pivotal movement being responsive 75 to the quantity of material supported upon the apron whereby variations inthe load of matevrial on the apron correspondingly varies the quantity delivered by the apron, a valved syrup supply pipe, the adjustment of whose valve lis controlled by the pivotal movement of said apron whereby the ratio of syrup to the sugar is maintained. e

4. In an apparatus of the class described, the

combination with variably spaced feed rolls fordelivering variable quantities of sugar, a pivotally mounted travelling apron arranged to rel ceive the sugar delivered by said feed rolls, means able amount of syrup to said mixing trough,l

for regulating the quantity of sugar delivered by said travelling apron to a mixing receptacle, means for supplying a predetermined but variable amount of syrup to said mixing trough, means for coordinating variations in the sugpply of syrup with variations in the supply of sugar, and

means for varying the spacing of said feedv rollers to prevent excess delivery of material thereby to the apron.

5. In an apparatus of the class described, the

combination with variably spaced feed rolls for delivering variable` quantities of sugar, a pivotally mounted travelling apron arranged to receive the sugar delivered by said feed rolls, means for regulating the quantity of sugar delivered by said 'travelling apron to 'a mixing receptacle, means for supplying a predetermined but varimeans for coordinating variations in the supply of syrup with variations in the supply of sugar, and means for varying the spacing of said feed Arollers to prevent excess delivery ofmaterial thereby to the apron, said means comprising roller-shifting means energized through the medium of the pivotal movement of the apron Vwhen under excessive load.

-6. In an apparatus of the class described, the combination with variably spaced feed rolls, a carrier apron for receiving and conveying to a mixing apparatus a regulated supply of sugar,

a syrup supply pipe provided with a regulating valve in coordinated relation to the carrier apron to maintain a substantially 'uniform' ratio of isyrup to sugar for delivery to the mixing trough a of acentrifugal apparatus, and means for pre'- venting an excessive accumulation of the mix. ture in said trough comprising a feed rollershifting mechanism and an energizing float member that is rendered Aoperative by the rise of material in said trough above a predetermined level.

`'7. In an apparatus for preparing mixtures of sugar crystals and syrup for centrifugingtheV combination with an elongated hot mingler a- -trough provided with bottom discharge chutes leading to individual centrifugals and an intermediate parted partition, revoluble internally heated stiriingand heating means mounted in sugar and the like, the combination of a sugar supply bin open at its bottom, a trough for receiving sugar from said bin, a liquid supply pipe for introducing syrup into said trough, valve means for varying the flow Pipe.

8. ,In an amnationapparatus for treating raw of liquid through said means for varying the amount of sugar delivered from said bin to said trough, and,

means connected with said valve means and responsive to variations in -the weight of. sugar flowing from said bin toward said trough for correspondingly changing the set ofsaid valve means.

' EUGENE ROBERTS.-

- CERTIFICATE oF cVoRREcEIoN. Patent No. 2,206,257'. July 2, 191m.

'EUGENE' ROBERTS.

It is hereby certified that error appears in the printed -specification of the above numbered patentrequiring c'orrectionasfollows: Page l, first column, lines 59 and lio, forthe words "'if no1; already'pzreset at this po1nt" page 4., second co1u1nn', ,"1inev15,lc1aim 7, strike out the article "a"; and

that/the said Letters Patent shonld vbereadwit'zh. this correction therein that the same jmayeonform tothe record of the case in the Patent Office.-

Signed and' sealed this 214th dey of September, A D. 19H0.

Henry Van Arsdaie, (Saai) Acting Commissioner of Patents.

Images