US1810369A - Refining hydrocarbon oils - Google Patents

Description

June 16, 1931. A, Q PETERKIN, JR 1,810,369

REFINING HYDROCARBON OILS Filed Dec. 4, 1928 i Pw i Patented June 16, 1931 UNITED STATES PATENT OFFICE ALBERT G. PETERKIN, JR., BRYN MAWR, PENNSYLVANIA, ASSIGNOR T0 THE ATLANTIC REFINING COMPANY, OI' PHILADELPHIA, PENNSYLVANIA, A CORC- PORATION 0F PENNSYLVANIA minnie Himnocannonl oILs Application led December 4, 1928. Serial No. 323,690.

My invention relates to im 'rovements in refining hydrocarbon oils, Aan particularly to an improved' process for the removal of certain objectionable properties from petroleum distillates, either cracked or uncracked.

Some petroleum distinctes, 'especially those .from 'crude oils which have a high sulphur content, contain objectionable compounds, the greaterportion of which are be'- lieved to be mercaptans, which impart to the distillates'a disagreeable odor and prevent them from meeting'ce'rtain standard specifications, such, for example, as the requirement that they shall react sweet to the doctor test described in Technical Paper No. 323--B of the Bureau of Mines.

My invention contem lates the treatmen of such distillates as a ove described, and especially those containing sulphur in the form of mercaptans, 'to improve their odor and render them sweet to the doctor test.

In accordance with my invention petroleum distillates of an objectionable character as aforesaid are treated with a suitable re-l agent or refining agent of such character that it may be revivified,. or maintained in or brought to an active state, by bringing it into contact with a suitable element or material, as oxygen or oxygen-containing gas. Such refining agent, for example, may be cupri-c chloride, lead compounds, such as lead sulphide suspended in sodium hydroxide solution, mercuric chloride, or the like;A but it shall be understood that my invention is not to be limited to these particular refining agents, for any equivalent may be utilized.

Further, in accordance with my invention, oxygen is added to the portion of the gas which remains after the oxygen-'containing gas has been in Contact the refining agent, whereupon the gas is again circulated through the system to revivify the refining agent.

One of the advantages of my invention is the practical elimination of loss of distillate in the form of vapors. Such loss is one of the decidedly objectionable features of prior out of the system with the consequent loss of distillate carried off as' vapors by the gas.

In carrying out my process, a given amount of air or other suitable oxygen-containing gas is introduced into a system closed, insofar as the circulation of the air or gas is concerned, impure distillate is continuouslyv introduced into the system, and a refined distillate is continuously withdrawn therefrom. During' the passage of the distillate through the sys' tem .it is treated with a suitable reagent or refining agent, as for example, cupric chloride in aqueous solution. The refining agent is revivilied, maintained in-or brought to an active state either continuously or intermit tently by the oxygen content of the airor other suitable gas. When the oxygen content or a portion thereof has been expended in the revivication'or reactivation of the refining agent, the air or gas is reoxygenated or brought to a suitable oxygen content by the addition of oxygen thereto, `either in a portion of the system substantially free from the refining agent, or in that portion of the systemin which the gas is in 'direct contact with the refining agent. In this way portions of the gas original y introduced into the system may be used indefinitely as a carrying medium whereby oxygen is applied to the refining agent for the purpose of revivifying it. By such procedure there is eliminated the loss of distillate normally resultin when a stream of gas is continuously passe into and be used in processes contemplated by my invention.

Fig. 1 illustratesone of the systems or4 forms of apparatus for carrying out aprecess embodying my invention.

Fig. 2 illustrates a modified system or form of apparatus which may be utilized in carrying out azurther process comprehended by my invention.

Referrin to Fig. 1, the oil to.be treated is delivere through pipe 1 to the pump M,

which delivers it in a continuous stream and lat suitable pressure into the reaction chaine the pipe in a ueous solution, introduced into the cham r A through the pipe 5, and with an o n-containin introduced throu h xyge 4. In pasisthrough the chambgr, the oil, refining a nt and gas are intimately commingled so t at substantially com lete reaction is effected. From the reaction c amber A, the mixture is passed through the pi e 2 into thezsettling chamber B, whereupon t e oil and refinin agent separate into layers and the unuse or residual portion of the gas passes to the top of the chamber, The oil separates as the upper layer and is withdrawn from the chamber through the valve controlled pipe 3 and run into a storage tank or otherwise-suitably disposed of. The refining a ent, which due to its continuous contact with the oxygen-containing gas throu hout its passage through the reaction cham er, has been constantly maintained in an active condition, forms the lower layer in said chamber, and is withdrawn through the pipe 5, whereu on it is a ain passed by means 'of um into and trough the reaction chamger X, Where it is brought into contact with further portions of the untreated oil.

The gas which collects in the upper part of chamber B, is that portion of the gas introduced into the reaction chamber A which di'd not react with or was not used in maintaining the refining agent in an active state, and its oxygen content is therefore relatively low as com ared with that ofthe gas introduced into the c amber A. This gas is Withdrawn from the chamber B through pipe 4 and again circulated by pump P into chamber A. During its passage from chamber B to chamber A oxy en is added thereto through the valve cont-ro ed inlet pipe 6 to replace that used -in maintaining the refining agentiii an active condition during the previous passage of the gas through the chamber A.

It will thus be seen that a system is provided wherein a continuous stream of oil may be treated, using a given amount of refining agent and a given quantity of gas, each of which may be recirculated, said quantity of gas acting as a medium by which oxygen is carried into treating relation with the refining agent. Under ideal operating conditions there is introduced into the system only amounts of oxygen'sufficient to replace the oxygen used up or chemically reacting to revivify the refining agent.

A system somewhat analogous to the system just described is shown in Fig..2. In this system at least partial revivification of the refining agent is effected by bringing the spent refining agent into contact or treating relation with the oxygen-containing gas While isolated from the oil, as in a chamber substantially free from the oil or distillate undergoing treatment.

` Referring to Fig. 2, the untreated oil is pumped through pipe 11 by the pump N into the reaction chamber C. Refining agent is introduced into the chamber through the pipe 17 and in assing through the chamber the oil and re ing agent are intimately mixed so that complete reactionv therebetween may take place. .S nt or partially spent gas is also introduce through the pi e 1 into the reaction chamber along with t e refining agent, as will hereinafter appear.

The intimately commingled oil, refinin agent and gas pass from the chamber through the pipe 12 into the settling chamberD where separation of the oil and refining agent into layers is effected, the gas passing to and collecting in the upper portion of the chamber. The treated oil forming the upper liqu id la er is withdrawn from the system throng the `Valve controlled pipe 13 and the spent refining agent which forms the bottoni layer is withdrawn through the pipe 15 and passed by um S into and through the revivifying c am e1` E.

The spent or partially spent gas collecting in the to of chamber D is withdrawn through pipe 14 and by means of pump R is delivered at suitable pressure into chamber E. During the passage of the gas through the pipe 1.4, oxygen is added thereto through the valve controlled inlet 16 to replace the oxygen removed from the gas during its previous passage through the system.

In the chamber E, the refining agent which is in a more or less spent condition is brought into intimate contact with the oxygen-containing gas and is revivified or reactivated,

thereby using up greater or less amounts of 2 the oxygen content of the gas. The revivified refining agent along with 'thegas whose oxygen content has been reduced is passed from chamber E throughpipe 17 into reaction chamber C as previously stated, whereupon the cycle or series of steps in carrying out the continuous process is repeated.

The process as described in connection with Fig. 2 is of particular advantage in insuring that the refining agent entering the reaction chamber is restored to the proper strength after prior utilization. The reaction between the refining agent and the oil which effects purification of the latter is, in general, a more rapid reaction than that of revivifying the reagent. Therefore, although the urification and revivification may occur simultaneously in the reaction' chamber A, Fig. 1, due to insufficient time of contact to complete the revivification, the reagent may become progressively weaker in refining properties upon continued recir.

culation. This result is avoided by interposing the step of passage through the chamber E, Fig. 2, in which the reagent is restored to substantially its former strength.

Under some conditions it may be desirable to effect revivication entirely in.the chamber E and to recirculate the residual gas through the chamber C substantially free from oxygen. lSuch procedure has the advantages of the agitation in the reaction chamber C effected by the passage of gas therethrough, which results in insuring intimate contact between the liquids and efiicientutilization of the refining agent.

When, for example, lead compounds, such as lead sulphide suspended in sodium hydroxide or plumbite solution is used as a reiining agent to sweeten hydrocarbon oils containing objectionable sulphur compounds, it is customa'nry to add an auxiliary reagent, particularly elementary sulphur to the reacting mixture. In my process, such auxiliary reagent may be introduced into the system", either admixed with the untreated oil entering at l or 11, or through a specially provided inlet, such as valve controlled pipe 3b communicating with chamber B (Fig. l) In instances Where a refining agent is used which due to the nature of its reaction with other substances present, results in the formation and accumulation of undesirable material or materials within the` system, suitable means are provided, as for example, valvecontrolled pi e 3a communicating with chamber B (Fig. 1i), by which such materials may be Withdrawn from the system. he gas introduced through pipe 6 or pipe 16 is preferably substantially solely oxygen, or equivalent, as from a tank or reservoir thereof under pressure. If the oxygen or equivalent introduced is in mixture with other gas, there will accumulate in the system an excess of inertv or carrier gas whichV Willv have to be drawn ofi' Afrom the system, continuously or at intervals. It is to be understood that this invention is l not to be limited to specific details as set forth herein but is to be considered as covering the processes described and such obvious modiicat-ions as may suggest themselves to those skilled in the art.

In the appended claims the term sweetening agent is used for brevity to cover refining agents of the type which will react with a sour hydrocarbon "oil to svveeten it, and which after effecting sweetening may be reviviiied, maintained in or brought to an active state by contacting with oxygen. Exaln les of such agents have been given, but Wit out limiting the invention thereto, since 'equivalent agents are contemplated by this invention.

lIVhat I claim is:

l. A continuous closed cyclic process for vtreating sour hydrocarbon oil, which comprises passing the oil in a continuons stream through a treating zone, during such passage subjecting the oil to the actlon of a confined.

quantity of sweetening agent capable of rcactivation by free oxygen, maintaining the sweetenine agent active by contacting it with a confined quantity of gas containing free oxygen, and replacing the oxygen consumed in maintaining the sweetening agent active by adding free oxygen to said gas.

2. A continuous closed cyclic process for treating sour hydrocarbon oil, which comprises passing the oil in a continuous stream through a treating zonc, during such passage subjecting thc oil to the actionv of a coniined stream ofsweetening agent capable of reactivation by free oxygen, rccirculating said agentintoandoutofsaidzone,maintainingthe sweetening agent active by contacting it with a confined stream of gas containing free oxygen circulating into and out of contact therewith, and replacing oxygen consumed in maintaining the sweetening agent active by adding free oxygen to said gas.

3. A continuous closed cyclic process for treating sour hydrocarbon oil, which com,- prises passing the oil in a continuous stream through a treating zone, during such passage subjectino the oil to the action of a confined stream ot sweetening agent capable of reactivation by free oxygen, recirculating said agent into and out of said zone, maintaining the sweetening agent active by-contacting it With a coniined stream of gas containing free oxygen circulating into and out of contact therewith, and replacing oxygenv consumed `in maintaining the sweetening agent active by'adding free oxygen to said gas While the latter is out of contact with said agent.

4. vA continuous closed cyclic process for treating sour hydrocarbon oil, which comprises passing the oil in a continuous stream through a treating zone, during such passage subjecting the oil to the action of a sweetening agent passing in a continuous stream into said zone, said sweetening agent being ca-v pable of reactivation by free oxygen, passing a gas containing free oxygen in a continuous confined stream into said zone to malntam -`the sweetening agent active,| removing the oil, sweetening agent and gas from said zone and separating them, returning-the sweetening agent and gas to the treating zone, and adding oxygen to said gas.

5. A. continuous closed cyclic processv for treating sourhydrocarbon oil, which comprises passing the oil in a continuous stream through a treating zone, svveetening the oil during such passage by subjecting it to thel action of a confined quantity of sweetening agent said sweetemng agent belng capable of reactivation by free oxygen, passing in a continuous confined stream into said zone, passing a gas containing free oxygen in a continuous stream into said zone to maintain the sweetening agent active, removing the oil",

sweetening agent land gas from said zoney and separating them, supplying loxygen to said gas, thereafter intimately commingling the as and sweetening agentto reactivate the atter, and passin the commingled gas and sweetening agent 1nto the treating zone.

6. A continuous closed cyclic process for treating sour hydrocarbon oil, which comprises passing the oil in a continuous stream throug a treating zone, during such passage subjecting the 011 to the action of a confined uantit of cupric chloride solution, maintalning t e cupric chloride active by contacting it with a confined uantity of gas containing free oxygen, an replacing the oxygen consumed in maintaining the cupric ch oride active by adding free oxygen to said gas.

7. A continuous closed cyclic yprocess for treating sour hydrocarbon oil, which com-v prises passing the oil in a continuous stream through a treating zone, during such passage subjecting the oil to the action of a confined stream of cupric chloride solution recirculating into and out of said zone, maintaining the cupric chloride active by contacting it with a confined stream of gas containing free oxygen circulatin into and out of contact therewith, and rep acing oxygen consumed in maintaining the cupric chloride active by adding free oxygen to said gas while the latter is out of contact with said agent.

8. A continuous closed cyclic process for treating sour hydrocarbonv oilg-which comprises passing the oil in a continuous Stream through a treating zone, during such passage subjecting the oil to the action of a cuprlo chloride solution passing in a continuous stream intoesaid zone, passing a gas containing free oxygen in a continuous stream into said zone to maintain the cupric chloride active, removing the oil, cuprie chloride solution and gas from said zone and separating them, returning the cupric chloride and gas to the treating zone, and adding oxygen to said gas.

9. A continuous closed cyclic process for treating sour hydrocarbon oil, which comprises passing the oil in a continuous stream through a treating zone, sweetening the oil during such passage by subjecting it to the action of a confined quantity ofy cupric chloride solution passing in a continuous stream into said zone, passing a gas containing free oxygen in a continuous stream into said zone to maintain the cupric chloride active, re-

'moving the-oil, cupric chloride solution and gas from said zone and separating them, supplying oxygen to said gas, thereafter in- -timately commingling the gas and cupric chloride solution to activate the latter, and

passing the commingled gas and cupric chloride solution into the treating zone. ALBERT G. PETERKIN, JR.

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