US2938838A - Apparatus for the distillation of liquid material - Google Patents

Description

y 1960' M. BALLESTRA 2,938,838

APPARATUS FOR THE DISTILLATION OF LIQUID MATERIAL Filed Jan. 24, 1955 56 APPARATUS FOR THE DISTILLATION OF LIQUID MATERIAL The present invention relates to processes for continuous steam distillation of one or more materials and to devices for effecting these processes. The invention is useful, for instance, for deodorization of oils, steam refining of oils and fats of low acidity, and neutralization of oils and fats.

One of the features of the present invention is to spray the material to be treated with a fine and regular mist. Accordingly, the material to be treated is sprayed with steam under a vacuum so as to assure that every particle of the material to be treated is in contact with the steam and is homogeneously treated.

States Patent A further feature of the present invention is to provide while the operating conditions of temperature and pressure are by far less severe than those conditions necessary in conventional distillation plants.

The present invention relates to the distillation of a liquid material by means of a distillation apparatus which 4 comprises means for premixing the material witha heated gas, then the premixture of the heated material and heated gas is supplied to a two-fluid nozzle opening to a distillation chamber, means being provided to supply additional heated gas to the nozzle to draw out the prernixture from the nozzle, and the interior of the distillation chamber is then exposed to a vacuum so that the interiorof the chamber is maintained at a relatively low temperature while the steam distillation of the liquid material proceeds therein.

Further, the deaeratlon is effected while the liquid material is at ambient temperature prior to the premixing thereof with steam, thereby to avoid oxidation and consequent damage to the liquid material. Accordingly, when deaeration is effected, this ensures that all air'or free oxygen will be removed from the liquid material prior to the heating thereof.

It is another feature of the present invention to provide an apparatus in which the amount of steam and material to be treated are re ulated independently in order to govern continuously the exact amount of steam with respect to the quantity of the material to be treated, so as to obtain an efiicient performance.

' Another feature of the present invention is to provide means for continuous feeding of the material to a plant through acontrol device or flow rate regulator. The material is then submitted to a deaeration under vacuum, thus avoiding any alteration of the material due to the presence of air during the heating period.

Another feature of the present invention provides means for subjecting the material to the heat of a material previously treated and distilled or to theheat of-a material treated and not distilled, or to both, thus allow ing utilization either of the heat of condensation of the steam distilled material or of the heat of the undistilled 2,933,838 Patented May 31, 1960 ice material for heating the supply material and resultingin a high saving ofsteam. v I

' Another feature of the invention is to cool the material, which has been treated and either distilled or undistilled, suddenly :ina barometric column with a jacketed discharge tube.

The product of the steam distillation is collected b Way of a barometric column, and heat is transferred from the distilled product to the liquid material to be distilled during passage through said column to preheat the liquid material following the deaeration thereof and prior to the premixing of the liquid material with steam. The combination of the use of a barometric column for dis charge of the distilled product and the preheating of the liquid material after the deaeration thereof ensures that the entire portion of the operation conducted at high temperature will be in the absence of air or free oxygen thereby to prevent oxidation of the liquid material.

It is stilla further feature of the present invention to provide a continuous discharge of the distilled or undistilled material through the barometric column, without the necessity of employing discharge pumps. This results in the advantage of discharging the material at a temperature' as low as it is desired.

Yet another feature of the present invention is to discharge the material, either undistilled or steam distilled,

through a jacketed barometric tube wherein either the distilled or the undistilled material flows in the jacket, so that the barometric column also performs the function of a heat exchanger.

Another feature of this invention is to make provisions for avoiding the formation of foam by means of very fine spraying. The foam formation is avoided even in materials which. are very viscous, thus eliminating the detrimental. elfects which result from the presence of foam in the conventional steam distillation appaartus'.

Additionally, a feature of the present invention is to provide different means of heating based upon the material to be treated and to its heat responsiveness in order to supply the necessary temperature and distillation calories, i.e. heating of the material, superheating of the steam and heating the sprayed material by radiation with the possibility of using, in the various cases, systems which are more convenient. Another feature of the present invention is to provide a special condensing apparatus in order to obtain, Where it is desired for the mixture of materials to be distilled, a fractional condensation of the various components, thus obtaining a separation by condensation in this case, every single condenser is fitted with a device for discharging the condensate, which device is, in the preferred form, a barometric column with a jacketed discharge tube.

Another feature of the present invention is toprovide a trap between the low pressure zone of an atomisation chamber and an opening for the outlet of the vapor of the material, in order to catch the entrained and undistilled droplets. Y

Another feature of this invention is to provide improved means for controlling the amount of material, means for controlling the flow of steam, and means of controlling the heat for radiation in a heater, allowing therefore the application of the plant to awide range of processes. I It is a further feature of this invention, in its application to' the deodorisation of oils, to efiect the deodo'ri: zation in the heat rational way, maintaining the oilsat a high temperature only for a very short period, thus avoid ing'absolutely any possibility of alteration'of theoiljs It as further object of this invention, i ;n;i'ts application to the steam refining of oils and fats, to 'slibinift'h'c Figure 2 illustrates a slight modification of the struc- V ture of Figure -1. r

Referring now to Fig. 1, the apparatus comprises a supply tank 1 containing for the material to be treated, into which dips a pipe 70 which is connected to a proportioning device 2 and to a vacuum deaerator 3; from the deaerator a pipe'7 leads to a heat exchanger 4 into which enters a heating fluid through line 5 and which is discharged through line 6; as indicated by a dotted line, duct 7 may be interrupted at A and coupled to pipe 8 connected at 39 with jacket 12 between tubes 13 and 14 (to be further described); the upper opening 40 of this jacket is then connected through pipe 9 to duct 7 which leads to the heat exchanger 4. Further it must be noted that pipes 8 and 9 may be also joined respectively with ducts and 11 connected at 51 and 52 to the jacket between tubes 15 and 16 (to be further described).

v I The nozzle 19 is fed through means of pipe 67, preferably fitted with a flow regulating device (not shown), with the steam coming from a superheater 29, into which the heating medium enters from 30 and from which the medium is discharged at 31. The medium is fed with the other fluid is superheated steam. In the upper part of chamber 21 is a trap 23 for recovering droplets. entrained by the steam without being distilled. Where there are more haflles 22, each has smaller dimensions from the top to the bottom of chamber 21. The lower part of chamber 21 is provided with a jacket 24 where a perforated pipe 25 is located, through which is fed steam coming through duct 27 and a regulating device 28 from the same or from another superheater 29, heated with steam arriving through a pipe, a flow meter and a regulating valve.

The open bottom of vessel 21 is connected with pipe 13 which has its lower end in a collecting tank 36 and the barometric column comprises the pipe 13 jacketed within a pipe 14; jacket 12 between the two pipes is divided into two parts by wall 38, i.e., the upper part being connected through 39 and 40 to the pipes 8 and 9 and the lower part being connected through 41 and 42to a source of refrigerating fluid, such as water.

- In its upper part, chamber 21 is connected, through pipe 43, to a condensation unit 44 (on more similar units) fitted with a jacket 45 where refrigerating fluid enters at .46 and is discharged at 47. The bottom of chamber 44 is connected to pipe 15 which has the same elements 16, 48, 49, 50, 51, 52, 53, 54 corresponding to the elements 14, 38, 41, 42, 39, 40, 36, 37 of the barometric column of chamber 21.

The upper part of chamber 44 is connected through pipe .55 to' a condenser 56, fitted with a barometric column 57 which terminates in a tank 58; 59 is a vacuum pump connected to the condenser 56 through the duct 60; a pipe 61 connects deaerator 3 and regulator 2 to the vacuum line.

The operation of the plant is as follows:

The material to be treated is sucked via the pipe 70 through regulator 2 owing to the vacuum produced by jump, is deaerated in deaerator 3 and fed continuously from the same and runs along jacket 24.

through pipe 7 to heat exchanger 4 from which, through regulating device 18and duct 17, it comes to nozzle 19; the steam flowing through valve 34, control 33 and superheater 29, is fed through pipe 67 to spraying nozzle :19. The heater 20 may be heated with steam, but may also be heated by other means The material being thus completely deaerated and properly heated, is sprayed into chamber 21 by vacuum and under high temperature conditions.

Owing to the temperature, vacuum and the fine atomization realized, an instant, perfect and complete steam distillation is obtained from one or more components of the material (in accordance with the characteristics of said components and with the regulation of the operation). V

The latent heat of distillation may be furnished either as heat given to the mass to be treated through heat exchanger 4, or as heat given by the superheating of the steam, or through heater 20 Where the heat is produced in a convenient manner, such as by radiating heat through a transparent tube to which pass the mixed components, or by means of infrared rays, or otherwise.

According to the use of the plant, the heating may be limited to one or two of the systems and, for some materials, which in conventional plants must be heated, it

is possible to eliminate completely the supplementary heating.

The portion of the treated material which does not distill in chamber 21 falls into the truncated cone-shaped bottom of chamberv2l where it is possible to subject it to another rinse with superheated steam, coming through the valve 76, control 35, superheater 29, conduit 27, the control device 28; said superheated steam circulates along a perforated conduit 25, is sprayed -While the portion of the material which is not distilled falls from the truncated cone of chamber 21 to the truncated cone external to jacket 24, it is subjected to the superheated steam current coming from perforated tube 25. These steam inlets also have the function of preheating the plant when it is desirable to avoid. the heating ofthe apparatus with a jacket.

The portion of the material which is not distilled falls through the pipe 13 which acts in its lower part as a water condenser and is discharged completely refrigerated at atmospheric pressure.

From what has been stated above, it will be apparent that the process of the invention comprises premixing a liquid material such as oil or a'fat in liquid form (a fatty acid) and distributing the mixture via a nozzle by means of an additional gas into a distillation chamber which is under a vacuum. Steam is the preferred gas and preferably the liquid material is deaerated before it is processed. Other specific features of the process have been noted above.

When the material to be treated and coming from deaerator 3 is passed through duct 8, in the upper part ofthe jacket 12 and/or through duct 10 in the corresponding jacket between pipes 15 and 16, barometric pipe 13 and/or 15 act also as heat exchangers. The material to be treated is thus heated by means of the heat of the material already treated. 1

The discharge of the material from the apparatus is thus efiected continuously .by means of a barometric column of a height corresponding to the specific weight of the lighter material which must be treated in the plant. 7

' .Theparticles of material to be treated undistilled and entrained by the steam are retained by trap 23 and directed to the bottom of the vessel; again the undistilled particles wlnch may hang. on the interior wall of vessel 21 will be dropped through pipe 13 by means of bafiies22. .The vapors of the material to be treated, which have passed through trap 23 mixed with steam, flow along pipe 43 towards the condenser to condenser units 44, where, according to the type of condenser, they are condensed in one or more fractions; the steam arrives at condenser 56 coupled to vacuum pump 59; the water is collected in tank 58.

It must be particularly noted that, when the material to be treated is very viscous, the formation of foam and the inconvenience brought about by foam are avoided due to the atomization.

Generally, there is the great advantage of eliminating the inconveniences deriving from long exposure of the material to elevated temperatures.

When the material to be distilled is the main or the total part of the material to be treated, it is necessary to provide a great quantity of calories as distillation heat.

Particularly, but not exclusively, it may be useful in this case to apply the modification illustrated in Fig. 2, where the material to be treated, coming from heat exchanger 4 and the superheated steam coming from superheater 29 are conveyed in a mixer 62, for example of the Venturi type, and then to a further superheater 63 fed from 64 with a heating fluid which is discharged through 65 and is then introduced into chamber 21 (see Fig. 1).

It must be also noted that in certain applications, it may be useful, as illustrated in Fig. 2, that the nozzle be disposed in 66, i.e. at the upper part of chamber 21.

Particularly, the process and the plant may be adapted for a great variety of operations only by means of the control of the amount of material which passes through regulator 2, and the control of the amount of steam used, acting on the various regulating devices 34, 76, 18, 28, and on the passing of the material through ducts 7 or ducts 8, 9 and/or 10, 11.

The structures described to illustrate the present invention are subject to many modifications and additions as for example:

Giving to the barometric column a development other than vertical, when it is necessary to increase the heat exchange surface, providing that the height difference between the bottom of chamber 21 and the free suflace level of the discharge tank of the colmn is not altered.

Efiecting the extraction of the product with other known means, such as, for example, with parallel drip Changing the means of vacuum production,

Using different types of condensers for steam,

Using more condenser units in order to obtain a fractional distillation.

Moreover, the plant may be used, to great advantage, for the concentration and deodorization of foaming materials, such as products which may give materials having the characteristic of generating, during use, a foam, detergent and emulsifying action. These and other modifications and applications must be considered as included in the fundamental scope of the invention as defined in the following claims.

What I claim is:

1. Distilling apparatus comprising a source of liquid material for distillation, a steam source, a distillation chamber, means creating a sub-atmospheric pressure in said chamber, a first conduit connecting said material source with said distillation chamber, a nozzle on said first conduit at the end thereof which is in the distillation chamber, a second conduit coupling said steam source to said first conduit intermediate said material source and distillation chamber for mixing the material with 6 steam, and a third conduit connecting said steam source with said first conduit at said nozzle for drawing the material through said nozzle whereby the liquid material is atomized with a large amount of mechanical and thermal energy.

2. Distilling apparatus as claimed in claim 1 comprising means for deaerating the material interposed between said material source and said first conduit.

3. Distilling apparatus as claimed in claim 2 comprising a receptacle for the distilled product and a heat transfer means including a barometric column coupling said distillation chamber to said receptacle for conveying the distilled product to said receptacle, said heat transfer means further including a jacket around said column in heat transfer relationship with the latter and interposed between sections of said first conduit so that the distilled product is cooled and the material to be distilled is preheated by heat exchange within said heat transfer means.

4. Distilling apparatus as claimed in claim 1, comprising a heater in said distillation chamber adjacent said nozzlef or further heating the atomized material,

5. Distilling apparatus as claimed in claim 4 comprising gutters at the sides of the distillation chamber directing condensate forming on the inside surface of the latter toward the center of the chamber, and a trap in said distillation chamber, said trap recovering material entrained by the steam without being distilled, a condensation unit coupled to said distillation chamber, a second receptacle for the distilled product, and a second heat transfer means coupling said condensation unit and said second receptacle and interposed between sections of said first conduit for transferring heat from the distilled product received from said condensation unit to the material to be distilled for preheating the latter.

6. Distilling apparatus as in claim 5; wherein said second heat transferring means includes a barometric column depending from said condensation unit into said second receptacle to carry the condensed distilled product to the latter, and a jacket around the last mentioned barometric column in heat transfer relationship with the latter, the last mentioned jacket being interposed between said sections of the first conduit in parallel with the first mentioned jacket to also receive material to be distilled. 1

References Cited in the file of this patent UNITED STATES PATENTS 1,372,477 Bodman Mar. 22, 1921 1,648,856 McEwen Nov. 8, 1927 2,179,833 Sondermann Nov. 14, 1939 2,202,007 Ittner May 28, 1940 2,261,939 Morlock Nov. 11, 1941 2,403,608 Payne et al. July 9, 1946 2,447,746 Ferris et al. Apr. 24, 1948 2,451,668 Egger et al. Oct. 19, 1948 2,500,194 McConnell et a1 Mar. 14, 1950 2,521,766 White et al Sept. 12, 1950 2,575,051 Egger et al Nov. 13, 1951 2,577,632 Roetheli Dec. 4, 1951 2,621,197 Thurman Dec. 9, 1952 2,625,505 Cross Jan. 13, 1953 2,647,862 Whitney Aug. 4, 1953 2,656,308 Pettyjohn Oct. 20, 1953 2,682,499 Thurman June 29, 1954 2,695,868 Brucke Nov. 30, 1954 2,695,869 Sondermann Nov. 30, 1954 2,702,268 Egger et al. Feb. 15, 1955

Claims (1)

1. DISTILLING APPARATUS COMPRISING A SOURCE OF LIQUID MATERIAL FOR DISTILLATION, A STEAM SOURCE, A DISTILLATION CHAMBER, MEANS CREATING A SUB-ATMOSPHERIC PRESSURE IN SAID CHAMBER, A FIRST CONDUIT CONNECTING SAID MATERIAL SOURCE WITH SAID DISTILLATION CHAMBER, A NOZZLE ON SAID FIRST CONDUIT AT THE END THEREOF WHICH IS IN THE DISTILLATION CHAMBER, A SECOND CONDUIT COUPLING SAID STEAM SOURCE TO SAID FIRST CONDUIT INTERMEDIATE SAID MATERIAL SOURCE AND DISTILLATION CHAMBER FOR MIXING THE MATERIAL WITH STEAM, AND A THIRD CONDUIT CONNECTING SAID STEAM SOURCE WITH SAID FIRST CONDUIT AT SAID NOZZLE FOR DRAWING THE MATERIAL THROUGH SAID NOZZLE WHEREBY THE LIQUID MATERIAL IS ATOMIZED WITH A LARGE AMOUNT OF MECHANICAL AND THERMAL ENERGY.

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