US1780977A

US1780977A - Process of and apparatus for steam distillation

Info

Publication number: US1780977A
Application number: US638175A
Authority: US
Inventors: Eugene H Leslie; Edwin M Baker
Original assignee: Individual
Current assignee: Individual
Priority date: 1923-05-11
Filing date: 1923-05-11
Publication date: 1930-11-11
Anticipated expiration: 1947-11-11

Description

Nov 11, 193Q. E.- H. LESLIE ET AL 77 PROCESS OF AND APPARATUS FOR STEAM DISTILLATION Filed May 11, 1923 pemtow 3.51 abtomaa J I Patented Nov. 11, 1930 UNITED STATES PATENT OFFICE EUGENE H. LESLIE AND EDWIN m. BAKER, E ANN ARBOR, MICHIGAN PROCESS OF AND APPARATUS. FOR STEAM DISTILLATION Application filed May 11, 1923. Serial No. 638,175.

vision of a process of and an apparatus for the steam distillation of solutions or mixtures, and the accomplishment of this object in a more eificient and economical manner than has heretofore been possible.

such a process to the distillation of petroleum oils or distillates and to recover various ffactions therefrom.

In the present application there are described an apparatus and a process that are in many respects similar to the apparatus and process described in our co-pending application, Serial No. 626,274, filed Mar. 20, 1923; and specific reference 'is made to said application for a description of the general manner in which liquids and vapors are treated, and for the general theory of operation.

Reference is also made to our co ending application, Serial No. 626,27 3, filed J. ar. 20, '1923, fora description of the operation of the vaporizer disclosed therein, which is in many respects similar to the vaporizer emtion.

The preferred embodiment of the present ging 2; andsaid fractionator is provided at the top with a vapor exit 3 leading to a re- .flux condenser 4, which may be operated I the vapors. away the uncondensed gases to a suitable absorber, and a reflux pipe 6 joins the bottom of the condenser to the top of the fractionator. The pipe6 serves to convey-the A, further object of the invention is'to apply ployed in the practice of the present invention; the figure of the drawing shows an ap-'- either as a partial or a total condenser or A pipe 5 is provided to lead condensed liquid to the top of the fractionator. A conduit 7 'having a number of conduits 8 branching therefrom to' the various sections of the fractionator, serves to conduct the hot liquid to the fractionator to be fractionated. Branch conduits8 are preferably provided for each section and a valve is placed in each conduit, so that the hot liquid may be conducted to any desired section of the fractionator, or to two or more sections 6 simultaneously. The fractionator is provided with any desired number of sections and the sections are provided with nipples 9 in order to permit liquid to descend from one section to the other, to permitvapors to ascend, and to cause liquid to accumulate onthe plates of the sections. Means are provided to withdraw this liquid from any section as desired; said means comprising a number of pipes'10, provided with valves and connected to the sections as shown and leading to suitable receivers. A suitable packing material 11 is placed within the sections for the purpose of providing a very large sur- 1 face of contact for the vapors and liquids, and this packing material may advantageously consist of ring or jackstone packings. Pro

vision may also be made for the removal of gases by suitably connected ipes.

, At the bottom of the fractlonator is shown 8 a pipe or conduit 12 that connects the fractionator to a vaporizer 13, which is operated to vaporize part of the liquid residue coming down the sections of the fractionator and passing through the conduit 12 into the vaporizer, A pipe-still 14'is connected to the vaporizer by means of

pipes

15 and 16, the former serving to conduct the liquid reslduum in the vaporizer to the still, and the latter serving to return it thereto-in a heated conditiqn. The ipe 16 may be provided with a pressure re ucing valve 17, and the pipe 15 has positioned 'in its circuit a pum 18 which operates to circulate the liqui The liquid delivered to the vaporizer strikes a bafile'19 from which the liquid spreads over a tower packing 20 and thence trickles downwardly through the' packing zone. A second packing 21 is provided above the f packing 20. A liquid exit 22 is connected to pose o the bottom of the vaporizer, and it is provided with a valve 23 operated by a suitable mechanism 24 that is controlled by a float 25 arranged as shown.

An open steam coil 26 is positioned in the lower portion of the vaporizer for the purinjecting steam into the liquid which collects therein.

The method of operation is as follows:

The oil, distillate, oriother liquid or mixture is pumped through suitable heat exchange devices iniwhich heat available in the residuum from the vaporizer, or from other source, is in part transferred to the incoming liquid. The latter then enters the manifold "or conduit 7 and is introduced into any previously selected section of the fractionato'r. The choice of the section into which the liquid is introduced depends on the nature and purpose of the distillation. If it is desired that the residuum from the still is to be free from the more volatil components of the liquid, but the distillate not entirely free from the less volatil components, the feed would be introduced into one of theupper sections of the fractionator. If it" is desired that the distillate contain only the volatil components of the liquid and that the residuum ;-need not be necessarily entirely free from the volatilcom onents, then the feed. would be introduce into. one of the lower sections of the fractionator. If both residuum and distillate mustbe sharply cut, the feed would be introduced into one of the sections near the middle of the fractionator. It will be evident that'the proper location of the feed section is in any case easily determined by trial.

In thefractionator, the process of change of composition ofdescending liquid and ascending vapor is similar to that described'in our co-pendingapplication, 'Serial No. 626,274, but it diifers in'this respect, that two liquids mix and descend that portion of the 'fractionator below the feed section, these liq-- uids being the feed liquid and the liquid run.-

ning down the column from the reflux condenser at the top thereof. Otherwise the changes and operations going on within the 'fractionator are substantially similar to those taking placein the fractionator of the above mentioned application.

The liquid flows from the bottom of the "fractionator through the conduit 12 into the vaporizer 13 where'it collects and is Withdrawn through the pipe 15 by means of the pump 18, and forced through the heater coils of the pipe-still 14, the pipe 16, and the valve 17. Upon discharge upon the distributing bathe-plate 19 it is spread over the surfaces of the packing 20, whereupon a portion of the liquid is vaporized. This vapor together with any that may have been formed in the" heating-coils of the still, ascends through the packing 21. During its passage throughthe .moved as the result of impingement on the surfaces of. the packing. The unvaporized liquid from the packing 20 together with downwardly flowing liquid from the fractionator collects in the bottom of the vaporizer 13. q

Steam is introduced into the vaporizer 13 under: the packing 20, and preferably through a perforated pipe 261located near the bottom of the vaporizer and Well beneath the surface of the liquid here collected.

Residual liquid is withdrawn from the bottom of the vaporizer through the pipe 22, and at arate controlled by the valve 23 actuated by the float 25 and mechanism 24 as indicated in the drawing.

introduction of the steam, flow upwardly throughthe

packing zones

20 and 21, where they mingle with the other vapors formed in and entering the vaporizer. The combined vapors pass through the conduit 12 to the fractionator for fractionation. The packing zones in the vaporizer also function in the fractionatingprocess in some measure in a manner similar to that of the packed sections of the fractionator proper.

The fractionated products and water are. removed either as vapors or as liquids from selected sections of the fractionator. If re.- .moved as vapors, condensers and coolersmay be provided, and if removed as liquids it is desirable to provide coolers. It is preferable to remove theproducts as liquids-since small piping may be used, and all condensing may bedone in the condenser 4. It is preferable to although if desired only a portion of the vapors may be condensed while the remainperform all the condensing in said condenser,

der is withdrawn. It is also preferable to remove the water as liquid water since in operating in this manner impurities and malodorous substances dissolved in the water are removed from the system.

Two important results are accomplished by the use of steam in distillation. First, the distillation can be conducted at a much lower temperature than if no steam is used, second, if the steam-distillation is conducted in such a manner that water as well as steam, is brought into'intimate contact with the liquids and vaof the products is usually improved as a result of the dissolving and extraction of malodorous substances by the liquid Water. The

,hydrolytic effect of the warm liquid water tice the beneficial results attainable by a comr bined steam-distillation and fractionation process more effective and eflicient than any used hitherto, and our apparatus provides a means for the practice of our process. It may .pors within the distillation system, the odor' or may not beessential to our process of steam-distillation that fractionation occurs of steam into the lower part of the vaporizer and prefer to introduce the steam at this point, it is obvious that similar results may be obtained by introducing either steam or liquid water into the vaporizer at some point other than the one indicated in the description of our preferred process, or into the pipe still, for in each of these cases advantage would be taken of the partial-pressure effect of the water vapor, and steam would be caused to ascend into the fractionator. Also, less favorable results can be obtained by the introduction of steam or liquid water into the fractionator.

Our invention is applicable to the treatment of various liquids, and it may advantageous- 1y apply to the re-running or steam distillat1o n of gasoline, to the reduction of kerosene to a desired flash point, to the reduction'of lubricating distillates to the desired viscosity, and to the distillation and fractionation. of petroleum oils, distillates, and products generally.

It is not essential to use a pipe-still, as other suitable heating means may be employed. A closed steam coil may also be positioned in the bottom of the vaporizer if so desired. 7

As many a parently widely different embodiments 0 our invention may be made without departing from the spirit thereof, it is understood that we do not limit ourselves to the embodiments described except as defined in the claims.

We claim:

1. A method of fractionating a petroleum oil comprising introducing it into a section of a fractionator, bringing ascending vapor column,- collecting liquidin the column sections, withdrawing a liquid product from any desired section, vaporizing part of the liquid residue leaving the lower end of the column, returning resultant vapors to the lower end of the column, introducing steam into the unvaporized liquid residue from the vaporization to produce further vapors for introduction into the lower end of the column, and then further heating and subjecting to flash-vaporization the final liquid residue remaining from the steam distillation and introducing the resultant vapors into the bottom of the column.

3. A 'fractionator for treating petroleum oils comprising a number of superimposed sections containing packing material, a va- 1.

porizer-having a vapor outlet connected to deliver vapor to the bottom of the fractionator and a liquid exit, packing zones between said outlet andexit, means for introducing steam into the bottom of the vaporizer, a heater for liquid, connected to receive liquid from the bottom of the vaporizer and to de liver heated liquid between the packing zones of the vaporizer, means forr'eturning condensed vapor at the top of the fractionator, means for permitting the descent of liquids and the ascent of vapors and for collecting liquid. in the sections, means for independently withdrawing liquids from one or more sections, anda conduit connected to one or more sections for delivering a liquid to the sections. '2 r In testimony that we claim the foregoing, we have hereunto set out hand.

' EUGENE H. LESLIE.

EDWIN M. BAKER.

into intimate contact with descending liquid the liquid flowing from the packing zones and introducing volatilized vapors forme thereby into the bottom of the fractionator.

2. The method of fractionating mineral oil which comprises introducing such oil into a fractionating column having packed sections and allowing it to flow downwardly therein in contact with ascending oil va ors, condens-' ing the vap leavin the top 0 the fractionating colufi.

and re g condensate to the