US2217931A - Process for treating tobacco - Google Patents

Description

Oct. 15, J. c. M CORKHILL I PROCESS FOR TREATING TOBACCO 4 sheets-Sheet 1 Filed April 5. 1937 INVENTOR u/[JJE C. fifCORK/f/LL ATTORNEYS.

Oct. 15, 1940. .1. c. McCORKHILL i 2,217,931

PROCESS FOR TREATING TOBACCO Filed April 5, 1937 4 Sheets-Sheet 2 INVENTOR JfJJE C. MCORKHILL A TTORNE r Oct. 15, I940.

PROCESS FOR TREATING TOBACCO Filed April 5, 1937 4 Sheets-Sheet 3 NVENTOR JESSE C. MSCORKH/LL BY vgguQ 67 68 4 A TTORNE Vi J. c. MOCOIRKHILL 2,217,931

J. c. MGCORKHILL 2,217,931 PROCESS FOR TREATING TOBACCO Oct. 15, 1940.

A TTORNEY-S' Patented Oct. 15, 1940 PATENT OFFICE PROCESS FOR TREATING TOBACCO Jesse C. McCorkhill, Jacksonville, Fla., assignor,

by mesne assignments, to The Guardite Corporation, Chicago, 111., a corporation of Illinois Application April 5, 1937, Serial No. 135,092

5 Claims.

This invention relates to the treatment of tobacco, and in particular, to a process for treating tobacco prior to its being made into cigars, cigarettes, and similar tobacco products.

One object of this invention is to provide a process of treating tobacco, whereinthe tobacco is subjected to the action of carefully regulated moisture in an inclosure so as to render the tobacco pliable and moist, and to remove some of the undesirable gums and oils from the tobacco leaves by volatilizing them.

Another object is to provide a process for treating tobacco especially adapted for the manufacture of cigars, wherein the tobacco leaves, either in the form of hands 'or bales" are treated by being placed in a partially evacuated inclosure and subjected to the action of water vapor at a-suitable temperature.

Another object is to provide-a process for treating tobacco comprising impregnating the tobacco with moisture in a partial vacuum, while maintaining a temperature sumciently high to volatilize certain of the undesirable oils and gums, allowing to stand for several hours, and again subjecting it to a treatment with live steam in admixture with water vapor in a partial vacuum.

Another object is to provide a process for treating tobacco leaves, particularly for cigar-making purposes, wherein the dry tobacco is placed in an inclosure from which the air is then partially removed, the tobacco being then subjected to treatment with steam, inradmixture with water vapor, at a temperature adapted to volatilize undesirable oils and gums. After standing several hours, the tobacco is then subjected to live steam admixed with water vapor for a short period in an inclosure, from which most of the air has again been removed. a

The term casing, as well known in the art, refers to substances commonly employed for conditioning tobacco leaves so as to improve their pliability and flavor.

In the drawings:

Figure 1 is a central vertical section, partly in side elevation, of one form of apparatus, which may be used for carrying out the process of this invention, with the end closure thereof removed.

Figure 2 is a right-hand end elevation of the apparatus shown in Figure 1, with the end closure in position.

Figure 3 is a. vertical cross section along the line 3-3 in Figure 1.

Figure 4 is-a left-hand end elevation of Figure 1.

Figure 5 is an enlarged side elevation, partly in section, of the'forward end of the apparatus, showing the means for facilitating the loading thereof with tobacco.

Figure 6 is a cross section along the line 6-6 in Figure 1.

Figure 7 is a side view of the measuring tank and heating arrangement associated with Figure 1.

Figure 8 is a modification of a portion of Figure 1, showing means for automatically control- 10 ling the temperature of the steam by a temperature-resp'onsive automatic steam valve.

In general, the process of this invention consists in treating tobacco with carefully regulated. moisture in a partial vacuum under a 'sufliciently high temperature to render the tobacco pliable and moist, to sweat it rapidly and to volatilize certain undesirable gums and oils therein,

Hitherto, it has been necessary to sprinkle the tobacco leaves and leave them to soak over night in order to remove the excessive dryness thereof. Ordinarily, tobacco is received at the factory either in the form of bales or "hands, consisting of a number of leaves bundled together and tied at the stem end only. This tobacco, when thus received, is usually. in a very dry condition,

and accordingly is very brittle and easily disin- 'tegrates.

In order to use the tobacco for making cigars, the ordinary treatment has included sprinkling the dry 'bales by hand, letting them stand for many hours in order to distribute the moisture properly, and then after casing, treating the ,tobacco in sweat-rooms feral-seam n two to six Weeks.

The present process and apparatus enable the tobacco to be treated immediately to supply the proper amount of moisture so as to render it pliable and at the same time to treat it by means of heat and moisture in such a manner as to remove certain undesirable oils and gums, and thereby to eliminate this long period previously thought necessary for sweating thev tobacco leaves in sweat-rooms.

Referring to the drawings in detail, Figure 1 shows a preferred embodiment of apparatus adapted to be used in subjecting the tobacco to the process of the ,present invention. This ,apparatus consists of an air-tight tank In having a rear end wall ll, permanently secured thereto as by welding, so as to form an air-tight joint'at the junction'l2. The forward end of this tank I0 is provided with a strengthening band l3 and a gasket l4, surrounded by a ring-shaped angle member l5. Arranged to engage the portions l3 and I5 is an end closure member I6 (Figure 2) having securing clamps l1 arranged at intervals around its periphery. The clamps |1 have incorporated therewith screw members l8, whereby the clamps-l1 may cause the end closure to engage the end of the tank l8 in an air-tight joint.

A hand e I9 is also mounted upon the end closure IS, the latter being supported by rods 20 anchored to brackets 2|, as by the nuts 22, the brackets 2| being secured as by welding to the end closur'e l6. At their upper ends the rods 28 are secured to a cross bar 23 by nuts 24, the cross bar itself being, in turn, attached as at 25 to a U-shaped supporting member 26, with a bolt 21 passing therethrough. Arranged to hold the supporting member 26 is a swinging arm 28 having a vertical shaft 29 and a supporting brace 30. The shaft 29 of the swinging arm 28 is mounted in a support 3 I, which is capable of being secured to an upright member, such as a post or pllaster (not shown), as by bolts or screws passing through the holes 32. The swinging arm 28 and the member 26 thus are adapted to sustain the weight of the end closure 6 and to enable it to be swung to one side when it is desired to make the tank accessible for loading, unloading or inspectiom Arranged immediately beneath the end closure I6 is a drip pan 33.

The bottom of the tank H1 is provided with a runway 34 (Figure 3) which terminates at its forward end in an angled supporting member 35 (Figure 1). This supporting member 35 serves as a rest for a swinging bridge member 36, hinged as at 31 to an inclined approach member 38. The members 36 and 38 are strengthened by the members 39 and 40, secured to the under sides thereof. Immediately beneath the hinge connection 31 is arranged a supporting member 4|, resting upon the floor. The bridge member 36, during the loading or unloading of the tank, occupies the position shown in Figures 1 and 5, with its forward end resting upon the ledge of the member 35. The end closure |6 in the meantime has been swung to one side, as shown in Figure 5. The tank I0, on its inner walls, is provided with a pair of longitudinally disposed troughs 42, secured to the walls in a water-tight manner, as by welding. These troughs 42 are arranged to receive water which may condense on the inner walls of the tank l0, and also to receive water which is deliberately supplied thereto by means of the pipe 43 (Figures 1 and 3) having a valve 44.

Beyond the valve 44 the pipe 43 is connected to a water supply line 45 by means of the T-connection 46. The water supply line 45 is provided with a pair of valves 41 and 48, and a T-connection 49. From the T-connection 49 the pipe 58 runs to a mixing connection 5|, where it joins the steam pipe 52. The steam pipe 52 is supplied at intervals with the valves 53 and 54. From -the mixing connection 5| a pipe 55 runs to a T-connection 56, the T-connection 56 leading, by means of a short pipe 51, to a port in the walls of the tank I. .Beyond the T-connection '56 the pipe 55 may be placed in communication with the atmosphere by opening the valve 58. On opposite sides of the mixing connection 5| the pipes 52 and 55 are supplied with T-connections 59 and 63, respectively, for the connection of a by-pass line 6|, having a by-pass valve 62 therein.

At the T-connection 63 the steam pipe 52 is connected to the steam supply pipe 64, the latter being connected to a suitable boiler or other source of high pressure steam. In Figure 1 the continuation of the pipe 52 to the left of the T- connection 59 is shown in side elevation, together with the valve 53, the T-connection 63 and the pipe 64 because this showing renders the disclosure of the piping clearer than ifthe piping were omitted, due to the breaking away of the tank at this point. The true relationship is clearly seen from Figure 4. Beyond the valve 53 the pipe 52 passes downward and is connected at the T-connection 65 (Figure 4) to the cross pipe 66 leading to the steam heating pipes 61 connected to the opposite ends thereof. 7

The steam pipes 61 pass through the end wall ll of the tank I, and lie within the troughs 42. At the rearward ends of the troughs 42 (Figure 3).the steam heating pipes 61 emerge from the troughs and pass downwardly, beneath the runway 34, near the bottom of the tank Ill. The steam heating pipes 61 continue'along the floor of the tank, beneath the runway 34, and terminate in the connection 68, from which the return pipe 69 leads through the end wall H to the steam trap 18, from which the condensate line 1| conveys condensed water back to the boiler. The

bottom of the tank is also provided with an outlet port 12 having a drain pipe 13 connected thereto, the latter including a drain valve 14. By opening the drain valve 14 any surplus water accumulated in thebottom of the tank may be drained away. Similarly, the troughs 42 are provided with an interconnecting drain pipe 15 (Figure 3), having a downwardly extending drain I line 16 connected thereto at the T-connection 11, and containing the drain valve 18. By opening the drain valve 18 the troughs 42 may be drained of any water, this draining being advisable at the beginning of the process after the process has been previously carried out.

For the purpose of supplying refrigerating fluid the refrigerating coils 19 are provided. These coils 19 consists of pipes running to and fro lengthwise of the tank I0 and connected at their outer extremities 88 and 8|, respectively, with the refrigeration cross lines' 82 and 83, connected as at 84 and 85 with the refrigeration inlet and outlet lines 86 and 81, respectively (Figure 4). A refrigeration valve 88 serves to regulate the ad- 'mission of refrigeration fluid to the refrigerating coils 19. Running lengthwise of the tank I0, im-

mediately beneath the uppermost portion there-,

of, is a fluid line 89 provided at intervals with nozzles 90 and having a valve 9| immediately beyond the point where the line 89 emerges from the tank III. This line 89 and its nozzles 90 serve for the distribution of casing fluid or other fluids.

Connected to a port in the wall of the tank In is the vacuum pipe line 92, containing a valve 93.

The vacuum pipe line 92 is connected to an evacuating apparatus, such as an air exhausitng pump for the purpose of removing the air from the tank after the end closure l6 has been clamped thereto. The moisture admitted through the short pipe 51 from the connection 56 is prevented from impinging directly upon the tobacco by means of the bafile plate 94,secured to the inner wall of the tank In. A thermometer 95 and a pressure gauge connection 96 are also supplied (Figure 6) for indicating the temperature and pressure existing within the tank Hi.

In the operation of the apparatus the tobacco, if in the form of bales, is placed upon a supporting rack structure 91 having shelves 98 for receiving the bales 99. The rack 91 rests upon a portable platform ||l|l (Figure 1), and the whole assembly may be transported by means of a portable lift truck of any conventional type. In one suitable type the lift truck is inserted beneath so of the air through the the portable platform I and then raised that it lifts the platform off the fioor and enables the entire assembly to be moved by means of the truck. If the tobacco is in the form of leaves or hands" these are placed in boxes or crates, the crates being open or latticed to permit the free passage of the moisture and other treating materials. These crates are then merely placed on top of one another, preferably two to each platform I00, the framework or rack 91 being dispensed with.

Thus the loaded platforms I00 are placed on the trucks and the latter rolled up the incline 38 and bridge member 36 into the interior of the tank I 0. The platform I00 is then lowered so as to rest upon the runway 34, whereupon the truck is removed and taken to the loading station for another load. In this manner the tank may be loaded with tobacco, beginning with the inner end of the tank and ending at the outer end with the final load. After the truck has been removed from beneath" the final load the bridge member 36 is swung upwardly about its hinge connection 31, until it occupies the dotted position shown at 36a in Figure 5. When this has been done the end closure I6 is swung on its supporting arm 28 and shaft 29 and urged by the clamps I1, I8 into an air-tight position engaging the front gasket I4 of the tank.

Air is withdrawn. from the tank I0 by the vacuum pump 97, through the pipe 92 having the relief valve '98, and discharged through the pipe 99 until an absolute pressure of less than one-half inch of mercury is reached. Steam between 40 and 80 pounds pressure from the pipe 64 is then admixed with water vapor just before being admitted to the tank I0. This steam'pressure corresponds to approximately 267 degrees Fahrenheit and 312 degrees Fahrenheit respectively. The temperature, period of treatment and amount of Water vapor so admixed are varied according to the kind and quantity of tobacco under treatment, so as to soften the tobacco and only a short time, as a more uniform treatment.

to render volatile the majority of the undesirable gums and oils in the tobacco. The exact temperature of the steam employed in the treatment is not material, as long as a high temperature is not maintained long enough to scorch or otherwise injure the tobacco. It is preferable to employ a lower temperature of treatment for a longer time rather than a high temperaturefor is efiected.

The tank is maintained at this .temperature between fifteen and forty-five minutes by an automatic steam control valve 530 under the control of a thermally-responsive device 53d (Figure 8), and having a by-pass line 53c with a valve 53b. Meanwhile, hot water is supplied to the troughs 42 through the pipes 43 and 45 from a steam-heated Water heater 100 (Figure '7), which in turn, receives water'through the pipe IM and valve I02 from the measuring tank I03. The latter is heated by a steamcoil I04, which receives steam from the steam line'64 by way of the pipe I and valve I06. The valve I02 has a graduated dial to permit reproduction ofv a given setting representing a given rate of flow. The water heater 100 receives steam by way of the pipe I01 and valve I08, and discharges into the pipe I09 leading to the steam trap H0. The tank I03 receives water through 'the pipes III and H2, and compressed air through the pipes H3 and H4 containing the valve 5 and pressure gaugellfiu. A valve IIB permits discharge pipe I while refilling the tank I03. The tank I03 is equipped with gauge glasses so that the amount of water-sup pliedfto the heater and thence to the troughs 42 may be accurately predetermined. When the water is allowed to pass from the measuring tank to the water heater at a very slow rate, the

heater will completely vaporize the water, especially at the subatmospheric pressure existing within the tank l0.

In this manner the hot water may be supplied through the pipe 43 in the" form of low pressure, low temperature steam.

tacts with the steam a part of said water may instantly become vaporized and another portion of the water in the form'bf entrained pare ticles is admitted into the chamber with the steam. The temperature of the steam is reduced by contact with the water and enters the chamber in-a condition of wetness greater than that which it had prior to contact with the water. Where it is desired to supply steam directly to the interior of the chamber, without supplying it to the heating coils 66, the valves 53 and 54 may be closed and the valve 62 opened, to permit the steam to flow through the bypass line 6| to the connection 56 and pipe 51, directly into the interior of the tank I0.

Steam passed from a boiler into a tank at a subatmospheric pressure or partial vacuum will become super-heated and cause the temperature of the tank and contents to rise to a higher temperature than is desirable before a .sufiicient amount of moisture hasbeen admitted'in the form of steam. In order to counteract the superheating effect, water is admitted in the manner previously described, either into the troughs 42 or directly into the steam as it flows into the tank I0 through the mixing connection 5| and pipe 51. Thus the steam may be used either to supply heat alone through the heating coils 61, or to supply both heat and moisture through the short pipe 51. The by-pass line BI provides a more rapid means for admitting steam to the interior of the tank, where the particular process does not require water to be added at the mixing connection 5I.

- When the troughs42 are filled with water, in the manner stated, this water is vaporized by means of the steam coils 61 passing through the troughs. This water in the troughs, if not accumulated in a sufrlcient amount by condensation on the walls of the tank, may be added by means of the pipe 43. Water condensed'on the walls of the tank below the troughs 42 flows to the bottom of the tank, beneath the runway 34 or floor, where it is subjected to the heat of the steam coils 61 as they continue along the floor of the tank. This water is thus revaporized by the portion of the steam coils lying on the bottom of the tank.

After the treatment has been carried out for a sufficient length of time the steam and water are shut off and the valve 58 is opened-to admit air to the interior of the tank. After this is done the end closure I 6 is removed and the tobacco withdrawn from the tank. When this tobacco is removed it is completely impregnated with moisture and is in a soft and pliable condition. The use of the water in combination with the steam permits the moisture content of the prodsupplying a suitable casing uct to be increased more, in any given temperature rise, than would result'from condensation of steam alone with the same increase in temperature'of the product. The tobacco is then in a condition to be shaken and treated with conditioning or casing fluid. Optionally, this casing treatment may be performed within the tank by liquid through the pipe 89 and the nozzles 90.

The tobacco is then allowed to stand from eight to twenty-four hours, after which it is again placed in the tank i0 and subjected to an additional heat-treatment in a vacuum having. an absolute pressure beween 1 and 2 inches of mercury. The heat-treatment is performed with live steam admixed with water vapor for a period of thirty to sixty minutes, according to the particular type of tobacco under treatment.

The valve 58 is then again opened to admit air and destroy the vacuum, after which the end closure i6 is again removed and the tobacco withdrawn from the tank. The tobacco is then shaken out and is ready for stripping. This process thus eliminates the expensive sprinkling of dry bales by hand, and the long periods of allowing them to soak in order to distribute the moisture throughout the leaves. The process of this invention also eliminates the necessity of placing the tobacco in sweat-rooms for a period of two to six weeks after casing.

When the tobacco is cased in the tank itself, without removing the tobacco from the tank, the valve Si is opened to introduce the-casing liquid through the nozzles 90.. The cased tobacco is then sweated in the tank l0, and needs only to be shaken after its removal before it is ready for stripping. It is found that the best results are obtained when the tank is initially dry, hence, the troughs 42 and tank In are drained by means of the drain connections 16 and 13, previously described, before the process is started. The tank is preferably preheated to the maximum tem-" perature to be attained during the process before the material is loaded into it. It will be understood, of course, that the tank In is surrounded by an insulating layer in order to conserve heat. This insulating layer is of heat insulating material, similar to that used on boilers or hot water surge tanks, and is omitted from the drawings in order to simplify the disclosure.

It will be understood that the pressure within the tank during the carrying out of the process is sub-atmospheric. Even though the boiler supplying the steam may be operating at a pressure of 40 to pounds, the tobacco does not actually come into contact with the steam at that pressure, but only after the steam has expanded to the pressure existing within the tank. The steam in this manner becomes super-heated or moist by reason of condensed water vapor, which is desirable for certain kinds of tobacco. By the additiqn of water the steam becomes moist low-pressure steam, which isdesirable for imparting a maximum moistening effect to the tobacco.

It will be further understood that the degrees of vacuum mentioned herein are not critical, but' are chosen because they are values used in practice and represent degrees of vacuum be conveniently obtained while carrying out the process. The invention is not limited to the which can range of degrees of vacuum mentioned because it has been found that a vacuum less than that represented by one-half inch of mercury absolute pressure at the start of the process also gives good results.

The casing fluid mentioned herein is a'solution of certain substances desired to flavor the tobacco and to alter the texture or pliability of the leaf. The presence of the casing fluid also assists in the further alteration and conditioning of the tobacco during the subsequent sweating or heattreating process. Various casing mixtures are used by different manufacturers, and the composition thereof forms no part of the present invention. The procedure in casing is to apply the solution to the leaves of the tobacco as uniformly as possible, either by dipping or by spraying.

The refrigeration coils 19 come into use in treating a charge of tobacco which contains sufficient moisture and heat to prevent securing a sufllcient vacuum for causing good penetration. In this case the charge can be refrigerated before the air is withdrawn so that the refrigeration step can be carried out in the same inclosure. It is also understood that this refrigeration might be carried out in a separate inclosure.

It will be understood that I desire to comprehend within my invention such modifications as come within the scope of the claims and the invention.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a tobacco treatment process, the successive steps of subjecting the tobacco to a high vacuum, and supplying to the tobacco amixture of steam and water whereby the moisture content of the tobacco is increased.

2. In a tobacco treatment-process, the successive steps of subjecting the tobacco to.,a high vacuum and supplying to the tobacco while under vacuum steam mixed with an amount of water in excess of that necessary to de-superheat the steam at the sub atmospheric pressures prevailing.

3. The method of moistening organic products in bulk, which comprises subjecting the product in bulk to a very low pressure in an atmosphere of steam and introducing liquid water thereto under higher pressure and in an extremely fine state of division, whereby the moisture content and temperature of the organic product is markedly increased, the increase in moisture content being greater than the increase in moisture content resulting from the condensation of steam on the product where steam alone is used with the some increase in temperature of the product.

4'. In a process for treating organic products the successive steps of subjecting the product to a high vacuum, and supplying to the product a mixture of steam and water whereby the moisture content of the product is increased.

5. A process for treating tobacco comprising subjecting the tobacco to a high vacuum, supplying to t. J evacuated tobacco steam and finely divided water entrained therewith, whereby the absolute pressure on the tobacco is increased and moisture is added thereto, and maintaining the tobacco in contact with the added steam and water at substantially constant absolute pressure for an interval.

JESSE C. MCCORKHILL.

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