US1684489A

US1684489A - Counterflow treatment of petroleum oils

Info

Publication number: US1684489A
Application number: US681472A
Authority: US
Inventors: Ralph A Halloran
Original assignee: Standard Oil Company of California
Current assignee: Standard Oil Company of California
Priority date: 1923-12-10
Filing date: 1923-12-10
Publication date: 1928-09-18
Anticipated expiration: 1945-09-18

Description

sept. 18, 192s. f1,6s4,489 f R. A. HALLORAN COUNTERFLOW TREATMENT OF PETROLEUM OILS FRESH ou.

:Wannsee mlm @wa/www sept. 1s, 192s. l 1,684,489

R. A. HALLORAN COUNTERFLOW TREATMENT OF PETROLEUM OILS Filed Deo. 19, 192,5 2- Sheets-Sheet 2 Patented Sept. 18, 1,928.

l l 1,684,489 )PATENT OFFICE.

j RALPH A. vHALLoRAN, or BERKELEY, CALIFORNIA, AssIGN'oR, BY IEsNE ASSIGN- MENTS, To STANDARD oIL COMPANY or CALIFORNIA, or sAN ERANcIsco; CALI- IoRNIAA CORPORATION or DELAWARE..

COUNTERFLOW TREATMENT 0]? PETROLEUM.' OILS.`

Application led- December 19, 1923. Serial No. 681,472.

This invention relates to a process of treating petroleum oils and refers particularly to the method of application vof gacid, alkali water and Washes of various sorts such as are employed during the manufacture of gasoline, lamp oils and other products frompetroleum oils.

As heretofore practiced, the treatment of petroleum oils with different reagents has been attended with considerable inefficiency inutilizing'that degree of strength in the reagents which is available for use in treating the oil. This is due to the fact -that as commonly applied, thereagent acts firstupo-n the most easily attacked ingredients of'the oil, which ingredients are removed upon the first contact of the oil with the reagent, and as the oil becomes progressively harder to treat, the reagent in contact with the oil becomes correspondingly weaker. As a result, a condition is soon reachedein which the reagent, While not entirely exhausted With reference to the .fresh oil, has no more potential strength With reference to the oil with which it is in Contact. If the oil, When this condition is reached, has not been acted upon to the desired degree, it must then be brought in contact with a fresh supply of the reagent.'

Various methods have been employed to secure the desired efficiency in the utilization of the strength of the reagent applied to the oil. The-se have included improvements in mechanical mixing and air agitation devices for batch treating, as Well as the use of nozzles and sprays for introducing the chemicals. Methods have also been devised for the continuous treatment of oil with chemicals. In these methods the chemical has been introduced continuously into a flowing stream of oil, or vice versa, so that 'both oil and chemical flow together through a treating vessel or through such mixing devices as small oriices,ballled pipes or mechanical mixers.

In both batch and continuous How methods as hereto-fore practiced the ingredients of the oil most easily acted upon are removed upon the first contacttof the oil Withthe fresh chemical. As the action continues, the oil becomes progressively harder to treat but at the same time must of necessity be acted upon by a Ychemical which has grown correspondinglv weaker. As a result. of this a condition is soon reached in which the chemical, while not entirely exhausted with reference` lto fresher oil, has-no more potential st-ren th with .reference to the oil With-Which it as b een 1n contact. If the oil, when this condition iis reached, has not been acted upon to the desired degree of completeness, it must then be brought in contact with a fresh 'supply of chemical which involves an additional labor cost together with complications which accompany additional applications ofthe chemical.

From the foregoing, it is evident that in the treatment of petroleum oils with reagents as heretofore practiced, all of the strength which is available in the chemical is not utilized and the spent chemical must contain considerable potential strength relative to the fresh oils or oils less completely treated, and considerably more of the reagents must be applied to the oil than should be necessary if the strength of the 'chemical could be properly utilized.

In my co-pending application, Serial No. 663,160, iled Sept. 17th, 1923, I have set forth a method whereby there is obtained a more complete utilization of the. strength of the reagents employed in the treatment of petroleum oils than has heretofore been employed. The method as therein described providesv that the reagents be applied -\to the oil in such a Way that it will flow continuously in a direction opposite or counter to the direction of the flow of the oil receiving treatment, thereby bringing fresh or less exhausted reagent continuously in contact With the most fully treated oil, or, vice versa, bringing the progressively exhaustincr reagent in contact with the progressively fresher oil to be. treated, all as more fully set-forth in the applica-tion referred to'above.

In the straight counterflow method as heretofore set forth in this co-pending application, the reagent is introduced at the top of a treating vessel in the form of a spray and descends as such to the bottom of the treater or to theaccumulated mass of spent reagent and reaction products -at the bottom of the treate'r. This deseension of the reagent'in finely divided form takes place against a rising current of oil. It will thus be noted that at any point inthe treating vessel in Which` the counter current action is taking place, the

ratio of partially exhausted reagent passing a given point to the oil undergoing treatment passing that point is approximately the same as the ratio of new reagent to the new oil introduced into the ,treaten Practically the only thing that will make these two ratios diil'er from eachother is the amount by which the volume of the oil is decreased by,having been acted upon by -the reagent and the amount by which the volume of the rea ent is changed by the reaction products w lch are formed. l- I I have discovered that by increasing'4 the amount of the partially spent reagent llowing counter to the oil at different points throughout the treating vessel so that at these points the ratio of reagent or partially spent reagent flowing counter to the oil undergoing' treatment is increased by a material amount over and above the ratio` of the new reagent to new oil being introduced into the counterflow treater a marked improvement in the quality of oil produced by the straight counterlow method is effected and a better utilizaion of the potential strength residing in the reagent obtained.

I have also discovered a method of increa's ing the'reaction between the reagent and oil in a counterflow treatment by withdrawing.

part of the'reactin mixture from the vessel and by mechanical y commingling andV agitating the same and then returning the mixture to the vessel, and by such comminglin of the reagent and oil the quality ofthe oi produced is improved while still effecting a counterflow treatment.

My invention will be better understood by reference to the attached drawings which are given for illustrative purposes' onl it being understood thatthe increasing of t e concentration of the reagentlwithin the oil undergoing counterflowtreatment to such an extent that the ratio of the reagent flowing counterto the oil being acted upon within the treater is materially increased over and above the ratio of reagent to oil being introduced into the treater is not limited to the particular` manner of accomplishing as herein set forth.

In the drawings, Figure 1 re resents a single counterfiow -tl'eater in whic there is carried out a two-step phase of my process of increasing the percentage of reacting reagent withinthe treater to a point inexcess of the percentage of new reagent being added to the oil. Y

Figure 2 represents a modilication'showing how the dierent steps can be carried out using individual counterflow treaters for each step. In addition, Figure 2 shows a threekali, water, etc.,) used for treating the same, it rises through thevessel A in a directionopposite or counter to the descending reagent which is conveyed b means ofthe pump 7 from a supply vesse 6 through pipe 8 and spray or spreading device 9 in to the top of the I ffents, which results from .the treatveyed from the treater .into pipe 10 and dis- [charged into the sewer or other suitable place for disposal. The level 12 of this sludged v material is controlled by the'valve 11, located in the draw-off pipe .1

13 represents'a gauge for determining the location of the sludge'level 12. l

14 and 14 represent partitions in the treating vessel A, dividing it into compartments AWA2 and A3. The sludge formed in compartment A1, together with the spenty reagent, will accumulate on the bottom 14, of compartment A1. Likewise' there will be an accumu-v lation of sludge and spent reagent on the bot-' tom 14'; of compartment A2. Through the Abottom or partition 14 there'extend downpipes 1 6. When the sludge accumulation on the partition or bottom 14 becomes Vsuilicient to cause the sludge level to rise to the top of d these down-pipes 16, it will overfiow into thesev down-pipes and descend through into compartment A2. Delectors 18 are arranged underneath these down-pipes, in order to scatter or break up into small particles this descending sludge.

15 represents a pipe forming a passage-way for the rising oil to flow from compartment- A2 into A1. This risingoil is scattered and broken up into small particles by 'means-of the deflector 17. .Likewise inthe bottom or partition 14', there are similar `down-pipes 16 anda passage-way 15. Deflectors 18 are located below pipes 16 and a deflector 17 is located above passageway 15',

19 and 19 represent centrifugal pumps which take suctions through pipes 22 and 22 on compartments A, and A2, respectively from polnts near the upper ends thereof.

20 and 20 represent lpes which lead from compartments A, an A2 respectively, at points near the bottom of these compartments and join the suction lines-22 and 22 respectively to form

suction lines

23 and 23 for the centrifugal umps- 19 and 19 respectively. The points rom which the

pipe

20 and 20 lead from compartments A, and'A2 are 1ocated below the sludge levels which are formed in these compartments so that a portion ofthe accumulated sludge and spent reagent may be drawn through

suction lines

20 and 20 respectively, and joined with the liquids which are drawn throughsuction lines 22 and 22' respectively. Valves 21 and 21', located in the lines 2() and 20', respectively, provide means for lcontrolling the quantities of sludge which are drawn into the pumps 19 and 19', respectively. The mixture of sludgefrom the bottom of each compartment A1 and A2 and the liquid drawn from the upper portions of thesesame compartn i ments is discharged by the pumps 19 and 19' treatment, whlch ratlo 1s` 1n excess of the lthrough the discharge lines 24 and 24' and through the spray nozzles and 25', respectively, into the upper portions of compartments A1 andl A2', respectively.

Itrwill thus be seen that by drawing a part of the accumulation of partially spent reagent which forms in`the bottom of compartments A1 and A2 into the suction lines of the centrifugal pumps and causing this partially spent reagent to join with the mixture of` oil and fresher reagent from the tops of these compartments there is `an addition of reacting reagent to the mixture of oil and reagent andthat the 'percentage of reacting reagent 'in the oil is thereby materially increased. f The amount by which this percentage maybe increased iscontrolled by a regulation of the

valves

21 and 21 located in the sludge suction lines. A material increase in thecontact of 'the reacting reagent with the oil is thus obtained, because there is a much greater proportionof reacting chemical to make contact Y There is also the added advantage of securing a more intimate' contact between the oil and the reagent because ofthe agitation which takes place in the centrifugal pumps. By'discharging the mixture with its increased content of reacting reagent from` the discharge spray lines located in the tops of the respective compartments, it is also seen that in those portions of the vessel in which the oil and reagent are contacting during their lcounterflow 'movements, there is an increased percentage of reacting reagent, or in other words, the ratio of reagent flowing counter to the oil where the treating or reaction is taking place is raised materially above the ratio of entering reagent to entering oil.

It will be noted that if the valve I21 in sludge suction line 20 is entirely closed so that all of the liquid fed to the pump 19 passes through the one line 22, the mixture then dis-d charged through line25 would have the same rat-io of reagent to oil as inthe intake line 22 or as elsewhere in the compartment. This ratio would be approximately equal to the. ratio of entering reagentto entering oil and there would be only the addition to a straight 'counterfiowl treatment of thegfeature of mechanical mixing.- The feature of mechan ical mixing 1n such a process 1sa valuable feature of thls inventlon which I desire to cover both with and without the increase of the ratio of reagent to reacting oil. To illustrate more clearly how my process .in the lines 20 and 20' agent, flowing counter, to the oil undergoing ratio of entering reagent toentering oil.

Furthermore, I am able to control this increase in the percentage of reacting reagent by introducing the accumulated sludge and partially spent reagent into the suction line of the circulating pump in controlled quantities. When this, increase in the ratio of reagent to oil is obtained, a marked improvement in the quality of treated oil over that obtained by the simple 'or straight counterflow process is effected. Moreover in addition tothe benefit obtained in the treatment Within the vvessel A the commin'gling of the mixtures drawn in the lines 22 and,22' with the reagent drawn espectively, permits such mixtures during thgir passage through lines 23 and 23', pumps 9 and 19' and lines 24 and 24' to be thoroughly treated by the increase of the ratio .of reagent to oil therein above the ratio of entering reagent to entering oil.- y It will be apparent that the treating vessel may be divided into any desired number of compartments .and the number of such circulating phases as described above increased to any desired number. It will also be apparent that the reagent need (not be introduced' into the top .of the treater, as shown in the drawing. It may, for example, be introduced at av point'in either the suction or discharge lines. of the circulating pump of vthe first or uppercompartment. By arranging a number of such treating vessels in series it will be apparent that a treating plant can be arranged that will providefor the continuous treatment of an oil with a number of different reagents, such for example as a preliminary lye or alkali treatment. an acid treat-ment, a neutralizing step, and the necessary water washings. My process is not limite'd'therefore to the action of a single reagent. v In'the modified apparatus vshown i'n Figure .2 in which the different phases of my process counter current treatment. When employingv the apparatus in Figure 2 the oil to be treated is drawn from an oil storage tank 30 through a line 31 by a pump 32 and enters the vessel B at a point near the lower end thereof, preferably being` discharged from a distributor or spraying device 33. The oil rises ing device 33 hence fiowing upwardly through the treater and out through the final discharge line 34". 'The treating reagent is drawn from the tank 36 and forced through a line 37 by a pump 38 into the upperend of `the treating vessel D being discharged into the vessel from a spraying or distributing device 39 into the uprising oil therein. The

' the line 41.

' a spray or distributing device 39.

reagent fed into the treater D passes down through the uprising oil and accumulatesat the lower end of the vessel where lit is maintained .at a substantially fixed level 40. From the lower end of the treater the reagent is drawn through a line 41 by means of a` pump 42 and forced through the line 43 into the upper end of the vesselC entering throriglh e reagent likewise passes through the vessel C to the lower end where it is maintained at a level Such as indicated by 40 and is continuously withdrawn through the line 41 by the pump 42 and forced through the line 43" into the upper end of the vessel B entering through the spray device 39. Similarly the reagent passing into the vessel B descends `against the uprising oil to the bottom of the vessel being maintained at a suitable level 40 and continuously withdrawn through 44 indicates a number of level gauges, one of which is supplied to each vessel for indicating the sludge level maintained therein.

The -lower ends of the treating vessels `B, C and D are respectively provided with

lines

45, 45 and 45 controlled by

valves

46, 46 and 46 respectively by means of which part of the reagent collecting in the bottom thereof may be drawn by the pumps, such as 42, 42 or 42 respectively, and forced upwardly through the

lines

43, 43 or 43 respectively,

`and discharged into the upper end of the respective treaters B, C and D `so as to increase the ratio of reacting reagentto oil maintained in the respective treaters.

The llines 4^5 and 45'. may introduce the reagent back into the treaters through the same lines and pumps as the reagent first entering the treaters or separate pumps and lines may be'supplied for such purposes.

'47, 47 and 47 indica-te lines connected to the uper ends of the vessels D, C, and B respectively, by means of which part pf the y mixture of reagent and oil present 1n the respective vessels may be drawn from the vessels and commingled preferably with the reagent to be recirculated, and as in the treaters B and C, the mixture may further be commingled with the reagent as it first enters the said vessels. It is thus seen that by the apparatus described in Fig. 2 a three step or phase coun,- ter flow process embodying thisv invention may be practiced.v

While the embodiments of the process herein described are well suited for the purposes of this invention, it is not intended to limit the invention to the details of the processes herein set forth for the purpose of illustrating the preferred examples of the invention, but various modifications may be made with out departing from the spirit of the invention. f

This invention is of the scope set forth in the appended claims.

I claim:

1. A process of treating petroleum oil with a reagent of substantially greater densityl than the oil and essentially immiscible therecontinuously into the same treating vessel and the spent reagent and resulting sludge to iow simultaneously out of the* vessel, caus' ing reagent within the vessel to ow in a direction opposite or counter to that of the flowing oil, accumulating within a portion of the treater partially spent reagent, 'and circulating to and from a region in which the flow of chemical and'oil is counter current a portion of this accumulation of partially spent reagent, together with such a portion rof the oil being acted upon that the ratio of reacting chemical to oil being acted upon in a portion of the treating apparatus is in excess of the ratio of entering chemical to entering oil.

2. A process o'f treatin peteroleum oil with a reagent of substantlally greater density than the oil andl essentially immiscible therewith which includes contacting a pro?` gressively exhausting reagent with a progressively fresher or less-treated o-il, simultan'eously contacting the same oil as it'becomes progressively more treated with a propressively stronger reagent, the reagent Howing in a. direction opposed to the flow of oil, simultaneously accumulating a; portion of the llo resulting partially spent reagent, and conv tacting such a quantlty of this accumulated partially spent reagent 'with a mixture of progressively exhausting reagent) and proflow of the oil in that part of the vessel becomes in excess of the ratio of the quantity of `new reagent to new oil.

3. A process of treating petroleum/'oil with a reagent of substantially greater density.

than the oil and essentially immiscible therewith which includes owing fresh oil continuously'into a treating vessel and continuously flowing treated oil out of the vessel,

simultaneously causing fresh reagent to flow continuously into the same treating vessel and the spent. reagent and resulting sludge to .ing oil, and simultaneously maintaining such a percentage`of reacting reagent flowing counter to the oil that the ratio of the current of eraeting reagent to the current of oil being acted upon, is in excess of the ratio of entering reagent to entering oil.

4. A process of treatinv petroleum oil with .a reagent of substantillly greater density than the oil and essentially immiscible therewith which includes passing fresh oil into a treating Vessel and continuously passing treated oil out of thevessel7 passing fresh reagent into the vessel and continuously-passing the spent reagent out of the Vessel in such manner that atleast a part of the reagent passes counter to the oil, repassing a part of t-he reagent through a part of the vessel countereurrent to the flow of oil therein, and forming a mixture of reagent and oil while flowing in opposite directions in the treating apparatus in which mixture the ratio of reagent to oil is in excess of the ratio between the fresh entering reagent and entering oil.

5. Aprocess of treating petroleum oil with Aa reagent of substantially greater density than the oil and essentially immiscible therewith which includes continuously passing fresh oil into a treating vessel and continuously passing treated oil out of the treating Vessel, continuously passing fresh reagent into the vessel and continuously passing spent reagent out of the vessel so as to flow counter to the oil, withdrawing from thevessel a mixture of reagent-and oil in which mixture the ratio of reagent to oil is in excess of the ratio of entering reagent to entering oil, and commingling and returning the mixture lt-o the vessel.

6. A process of treating petroleum oil with a reagent non-miscible therewith, vwhich 'includes bringing the oil and reagent into contactwith each other in a treating path inwhich theoil enters the endl of the path adjacent-the point at which the reagent is withdrawn from the path and in which the reagent enters the path adjacent the point the ,oil' is withdrawn therefrom, withdrawing from the path a mixture of the oil and reagent and commingling the same and returning the same to the path, separating atleast part of the reagent from the oil in one por.- tion of the path, and recirculating part of said reagent again through a portion of the path to thereby enrich the proportion of reagent to oil passing through such lportion of the` path. y

7. A processof treating petroleum o il with a reagent non-miscible therewith, which comprises continuously bringing streams `of oil.,

and reagent into contact with each other in a treating'path in which the oil enters the path adjacent the point at which the reagent is discharged from the path and in which the reagent enters the path at a point adjacent where the oil is discharged from the path, removing admixtures of oil and reagent at a plurality of points in the treating path, commingling said mixtures, and returning 4the same to the path, and separating part of the reagent from the mixtures in the pathl l and recirculating said separated reagent through a portion of the path so that the ratio of reagent to oil passino' through that 'portion of the path is increase 8.' A continuous process of treating petroleum oils Aand with a liquid reagent substantially immiseible therewith comprising continuously supplying fresh oil into a treating vessel and continuously removing-treated oil from such treating Vessel, simultaneously continuously supplying fresh reagents to the treating Vessel so as to cause the reagents to flow in a direction opposed to the flow of oil being treated, accumulating partially spent reagent within a portion of said treater and circulating said aceumulatedpartially spent reagent counterurrent to the oil being treated so as to maintain a larger ratio of reagent to oil within said treater thanthe ratio of fresh reagent and oil supplied to. said treater and removing spent reagent.

Signed at Richmond, Calif., this 11th day of December, 1923.v

' RALPH A. HALLORAN.