DocketNumber: No. 6213
Citation Numbers: 106 F.2d 644, 36 U.S.P.Q. (BNA) 42, 1937 U.S. App. LEXIS 2445
Judges: Biggs, Buffington
Filed Date: 12/21/1937
Status: Precedential
Modified Date: 10/18/2024
Sur Second Rehearing.
Following rehearing and decision in this case, another petition for rehearing was
In our previous opinion we emphasized the fact that the Lewis patent showed a means for returning the lighter hydrocarbons to the main column from the auxiliary fractionating towers. We therefore attached importance to a feature of the Lewis process which was not an essential to its operation. Though Lewis shows means for returning the vapors of the low boiling components to the main fractionating column, such means are rarely made use of in the Lewis process. We deem it necessary, therefore, to consider the Lewis patent again in the light of the prior art. We will discuss five of the patents alleged by the appellee to be pertinent upon the issue of anticipation.
Patent No. 1,676,232, issued to Weisberg July 3, 1928, on an application filed November 29, 1921, discloses a system for the “fractional condensation of mixed vapors.” Weisberg displays a fractionating tower or column so arranged that all of the vapors enter at the bottom of the column and pass up through plates spaced at intervals through the tower. Caps arranged at each plate force the upflowing vapors through the liquid formed by condensation at each plate. The overflow passes down from plate to plate through connecting pipes. Weisberg shows two side stream draw-offs, a vapor outlet running from the top of the column as a means of withdrawing the lighter hydrocarbons and a condensate outlet at the bottom of the column for removing the bottoms to storage. Weisberg makes no provision for stripping any of the fractions taken out of the tower. We find in the patent however reference to the principle of reflux, though not in the terms expressed by Lewis. Weisberg refers to an arrangement of tower “sections”, so that the mixed vapors and the condensate “flow through them in series but in counter-current direction to each other, thus bringing the heavier condensate and mixed vapors into heat interchanging relationship.”
We have attached the drawing accompanying the patent to the appendix to this opinion.
Two patents issued to Peterkin and others are alleged by the appellee to constitute part of the anticipation of Lewis contained in the prior art. Patent No. 1,709,874 was issued April 23, 1929 on an application filed June 4, 1925. A method for the distillation of oils is disclosed. Draw-off lines are shown running from a fractionating column. Intermediate fractions are to be run to coolers and thence to storage. A pipe is connected with the bottom of the column and a chest delivers superheated steam into its bottom section. This arrangement strips the heavy ends, but there is no provision made for stripping the intermediate fractions. The vapor inlet pipe is shown between the second and third bubble plates at a position almost identical with that shown by Lewis. The Peterkin patent is designed for the primary purpose of obtaining distillation while avoiding cracking. Peterkin makes reference to steam stripping of the lower ends within the tower for he states, “The unvaporized oil flows downwardly in the tower C, while in intimate contact with the upwardly flowing steam, accumulating at the lower end thereof as bottoms, with resultant vaporization of lower boiling point components, and imparting to the bottoms a higher flash test. The bottoms are continuously or at suitable intervals drawn off through the cooler F to the storage tank S.” The principle of reflux is not referred to. Peterkin sought to combine the function of the steam stripper for the bottom fraction with the withdrawal of intermediate fractions from the tower, but he seeks to do nothing more.
A copy of the drawing accompanying the patent is contained in the appendix.
A second patent for oil distillation was granted to Peterkin and his collaborators on April 23, 1929, upon an application filed April 14, 1926. Since Lewis’ filing date is earlier, this patent cannot be considered as part of the prior art.
Patent No. 1,614,689 was issued to Primrose January 18, 1927, on an application filed April 7, 1921. This patent is for an “improvement in processes for distilling crude oils.” Oil vapors are run through “a tower or like device where the volatile vapors are separated from the remaining oil or residuum, and are then passed through a series of air cooled condensers, the temperature of each being controlled by the amount of air passing through it, so as to condense out the heaviest hydrocarbon vapor, the remaining vapor being passed to the next succeeding air cooled condenser and so on through the series.” Nothing thus far hints of any stripping process. Primrose provides, however, in a later passage of the patent for the conveyance of superheated steam to the
The drawing accompanying the Primrose patent is attached to the appendix.
In Patent No. 1,868,466 issued to Leslie and Baker the appellee claims that there exists an almost word for word anticipation of Lewis. This patent issued July 19, 1932 upon an application filed June 29, 1925. We have appended a copy of one of the drawings accompanying the patent to this opinion. Leslie and Baker state in their specification :
“This invention relates to distilling processes and apparatus; and it relates more particularly to processes of and apparatus for distilling petroleum to produce therefrom one or more distillates of closely controlled composition, together with a residuum substantially free of components properly characterizing the distillate or distillates sought.
“A principal object of the invention is to provide a simple, effective, and economical method for the continuous distillation of petroleum or other liquid of mixed composition for production of distillates of the character above mentioned. A further object of the invention is to provide apparatus whereby the foregoing object may be achieved while at the same time utilizing to a large extent previously installed refinery equipment, such as batteries of stills, by associating with such equipment suitable fractionating apparatus, thus providing a complete apparatus system appropriate for practicing the invention at the lowest cost consistent with the accomplishment of the desired result.”
As to the actual operation of their process Leslie and Baker state:
“The vapors from each still are introduced into a suitable rectifying or fractionating system at suitable points. In the installation illustrated in Fig. 1, this rectifying or fractionating system consists of a single fractionating column, indicated generally at C, having an appropriate number of bubblercap sections which may be of any usual or-suitable design. It is not essential that the rectifying column be of the bubbler-cap type, the essential point being that the apparatus be' of such character as to afford full opportunity for countercurrently contacting upwardly flowing vapors with downwardly flowing liquid under conditions ensuring an approximation to equilibrium conditions at all points in the rectifying system. Such conditions can be realized in certain other forms of columns, such as packed columns, for example. In general, the distillation vapors from the several stills of the battery should be introduced into the fractionating column at such respective points that the vapors introduced at any one of said points will be, as nearly as is practically possible, in equilibrium with the vapor and liquid within the column at that point when the entire battery of stills and the column are functioning smoothly and properly in the regular course of operation. «* * *
“At 34 is indicated a small exhausting column into which liquid from the bottom of the main fractionating column C may be run. The use of this exhausting column is optional and is dependent upon the nature of the product that it is desired to obtain from the bottom of the column. Ordinarily, the apparatus may be so run that the liquid from the bottom of the column contains a negligible proportion of gasoline, say less than one to three percent. If it were desired to produce from the bottom of the column a liquid product containing no gasoline and possibly not even a lighter part
“Where the exhausting column 34 is not employed, or at least operates on less than all of the liquid leaving the bottom of the column C, liquid leaves the bottom of said column C through pipe 36 which delivers it to cooler 37. In the present example this liquid may be assumed to be a gas-oil fraction. If the kerosene can not be included either in the gasoline or in the gas-oil fraction, it must be withdrawn at some intermediate point along the column. In the present instance, the kerosene fraction is withdrawn through pipe 38 and header 18a from that section of the column C indicated at 39. This kerosene fraction is delivered into an exhausting column 40 which contains a heating coil 41 in its base. The vapors leave the column 40 through pipe 42 and pass into condenser 43 where condensate is formed and refluxes through pipe 44 back to the top of the exhausting column 40; while the uncondensed vapors are delivered through pipe 45 to vapor-manifold 46 from which they can be directed into any desired section of the fractionating column C. In this way, liquids of various compositions can be removed from the column C through suitably located draw-off lines, 38, 38a, 38b, 38c, and any one of the liquids so removed may be treated in an exhausting column as desired. That is, if it be found that from no section of the column can a liquid of exactly the desired composition be withdrawn directly, this procedure can be adapted to obtain a liquid of the composition desired. A liquid can be withdrawn from some one section of the column C that is of such composition that its higher boiling portion is satisfactory. The volatile end of this liquid can then be removed in an exhausting column and the vapor so formed returned to the column C at the point where it is most nearly in equilibrium when the column is operating normally.
“If desired, that portion of the auxiliary exhausting column 40 above the feed section into which liquid is delivered through pipe 38 may be omitted. The sections above this feed section perform a rectifying function, and in some instances would be unnecessary beca,use it would be immaterial whether a portion of the heavier components in the liquid fed in through pipe 38 was or not vaporized and returned to the main column C. If the upper sections of column 40 were omitted as suggested, it would mean that the liquid fed to the top of the exhausting column through pipe 38 would function as the reflux, the arrangement in this case being similar to,that shown for the other exhausting column 34.”
Claims 1 and 2 of this patent are for apparatus. Claim 3 is for the process, as follows ;
“3. The process of distilling liquids of mixed composition which comprises passing such a liquid serially through a plurality of suitably heated distilling chambers, con-ducting evolved vapors from all of said distilling chambers into a unitary rectifying system, condensing rectified vapors leaving said rectifying system, providing a rectifying counterflow of liquid in contact with said vapors in said rectifying system by refluxing at least a part of the condensate from said rectified vapors to said rectifying system at a point adjacent where said rectified vapors leave said system while avoiding introduction of counterflow liquid, as such, elsewhere into said system, the evolved vapors from each of said distilling chambers being introduced into that part of said rectifying system where they will be respectively substantially, in equilibrium with the vapor and liquid in said system, removing from said rectifying system an intermediate fraction of an approximately desired composition, exhausting said fraction of its more volatile portion to obtain a product of an exactly predetermined composition, returning said more volatile portion to the rectifying system at such point as to be in substantial equilibrium with the liquid and vapor in said system, and withdrawing a desired distillation product from a point in the combined rectifying and condensing system.”
The claims of the Lewis patent in issue are set out in a foot note to our previous
•The problem in respect to anticipation is the following. Leslie and Baker have put the elements of the Lewis process upon the pages of their patent. The principle of reflux is referred to; the exhausting col.umns or steam strippers are present. Leslie and Baker refer to the very ends which Lewis attains. Apparatus is displayed and a method of operating that apparatus to the stated ends is disclosed. It is all set forth; but will the process work as it is disclosed ? If so, anticipation is clearly shown.
We state as our opinion that the Leslie and Baker process and apparatus will not give the results which Lewis demonstrably has obtained, viz., hydrocarbon fractions sharply cut at their upper ends. The Leslie and Baker apparatus and process does not disclose a workable system which will give the results claimed for it. The reasons for this conclusion are as follows. In Figure I of the patent, the figure used by the patentees to display the working of their apparatus and process, -Leslie and Baker -show a series of stills, four in number, hooked tándem, ■ which pass their contents into the fractionating column at various points intermediate the top and bottom. As has been stated, the draw-off lines run from the side of the- fractionating column at points intermediate its top and bottom. The side streams are run to exhausting columns and thence to storage. But the insurmountable difficulty which lies in the way of obtaining sharply cut fractions free of heavy ends in the Leslie and Baker process lies in the position of the vapor-intalce pipes leading into the column from the four stills. Two of these are above the midsection of the column; one, that leading from Still I, comes into the column near its top. Since hydrocarbon vapors come from Still I into the fractionating column at a point not distant from its top, the reflux must contain heavy ends. That portion of the reflux which is not withdrawn to the side steam stripper 40 remains in the tower but cannot move in effective counter-flow contact with the vapors coming into the tower in the earlier stages of the fractionating process, as, for example, from Still IV. The Vapors from the four stills cannot come into effective contact with one another or with the reflux, for they are fed into the tower at different levels. Inevitably, the side stream to the stripper 40 must be contaminated with the heavier hydrocarbon vapors.
The appellee points out that Leslie and Baker state that the contents of the side stream in respect feo “its higher boiling portion is satisfactory”, but there is no evidence to support this statement of the patentees. That the appellee realizes the existence of the difficulty we have referred to is apparent from its argument, for the appellee states, "Manifestly Leslie could have run all of the vapors from his stills I, II, III, and IV, into a common pipe, such as that designated at II in the Weisberg patent, and introduced them all into the bottom of the rectifying column, ás Weisberg does, and as Peterkin passes all of the vapors from the separating chamber into the bottom of his rectifying section.” Leslie and Baker could have shown this but they did not show it.
Moreover, Leslie and Baker admit that the intake into the column from Still I must contain a proportion of the higher boiling constituents of the petroleum. These must move downward with resulting contamination to the upflowing hydrocarbons and the side stream. Indeed Leslie and Baker state that if the intermediate fractions are to be free of heavy ends, they must be withdrawn as vapors and not as liquids. It is' our conclusion that the result of the operation of the Leslie and Baker process and apparatus cannot produce the products claimed for it. We conclude, therefore, Leslie and Baker cannot be deemed to anticipate Lewis.
We have set forth the drawing accompanying the Lewis patent in the appendix. In' Lewis the vaporized petroleum enters the fractionating column between the second
Lewis combines the principle of reflux with the effective use of side stream draw-offs further treated when withdrawn from the main column by the auxiliary fractionating towers as part of a continuous system. The side streams, sharply cut at their upper ends, are gotten out of the tower and given further treatment while the fractionating process continues within the main column. While withdrawing side streams, Lewis continues the balance of the reflux ■down through the column. The side streams withdrawn are raised effectively in flash point by the auxiliary fractionating columns which serve as open steam strippers. The result is one which the art had sought, but which had not been achieved prior to Lewis. 'The great commercial success of the Lewis -process cannot be doubted.
The individual tools of the art used by Lewis are old. He has combined them, however, to reach a useful and, in a limited sense, a new result. The employment of the principle of reflux and of auxiliary steam strippers placed outside the fractionating column but not connected therewith to achieve desired fractions of hydrocarbons, was old, but this had not been accomplished in a continuous process with the -auxiliary fractionating towers connected to the main column. So much is new. The essential point which Lewis grasped was the necessity of putting the vaporized hydrocarbons from the still into the fractionating column at such a point that the in-coming vapors with their heavy ends would not contaminate the side streams in conjunction with the cutting of the side streams io the desired flash point by auxiliary fractionating towers or strippers. Weisberg .and Peterkin seem to have grasped it likewise.
That Lewis has shown mechanical ingenuity in adding the auxiliary steam strippers is not open to doubt, but has he display-ed inventive genius ? This is the crux -of the case at bar in view of the fact that no exact anticipation is displayed in the prior art. His disclosures seem the re.sult of a regular development of the art of fractionating hydrocarbons, he adding an -.ingenius and commercially valuable step. But, in the light of the development of the prior art, we cannot conclude that the end which Lewis achieved was the result of that incandescent and illuminating instant in which the mind grasps a hitherto undisclosed principle and with it achieves a new result whether by new tools or old. Lewis must be held not to have displayed inventive genius.
We therefore reverse our former conclusions and hold that the claims sub judice are invalid for want of invention.
Accordingly, the decree of the court below is affirmed.
DICKINSON, District Judge, participated in this decision.