Patented May 23, 1939 2,159,312

UNITED STATES PATENT OFFICE 2,159,312 PROCESS FOR BREAKING OL-N-WATER, TYPE PETROLEUM EMULSIONS Carles M. Blair, Jr., Webster Groves, Mo., assign or to fhe Tret-O-Lite Company, Webster Groves, Mc., a corporation of Missouri No orawing. Application December 13, 1937, Serial No. 179,471 1. Claims. (CI. 196-4) This invention relates to the treatment of a tive colioid or equivalent thereof. To this extent, certain peculiar kind of naturally occurring crude although not necessarily due to this factor alone, oil emulsion and has for its main object to provide these particular or peculiar oil field emulsions, a practicable process for separating the water ianiely, the naturally occurring oil-in-water ... and oil contained in said peculiar emulsion. emulsions having a significant proportion of dis 5 The vast majority of petroleum emulsions are of persed phase and a substantially complete absence the Water-in-oil type and comprise fine droplets Of a protective colloid or equivalent substance of naturally occurring waters or brines dispersed appear to be substantially a new type of emulsion in a more or less permanent state throughout the that requires a new method of treatment, in 10. oil, which constitutes the continuous phase of the order to separate them economically and rapidly O emulsion. They are obtained from producing into their component parts, and thus permit the wells and from the botton of oil storage tanks, recovery of dry or merchantable oil, and are commonly referred to as "cut oil', 'roily It is to be emphasized that the external phase oil', 'emulsified oil', and 'bottom settlings'. The o: continuous phase of these peculiar naturally 5 preSent invention is not concerned with the treat CCCurring petroleum emulsions consists of water 5 ment of such conventional water-in-oil type pe or a relatively dilute brine that apparently does troleum emulsions. not froth, that apparently has a normal surface In certain oil fields, there are produced crude tension, and which on evaporation, does not ap oil emulsions which, instead of being of the pear to yield a Substance having the character 20 Water-in-oil type, are of the oil-in-water type, istic properties of hydrophile protective colloids 20 and comprise fine droplets of naturally occurring or common emulsifying agents for the oil-in-water petroleum oil dispersed in a more or less perma type of emulsion. nent State throughout the water or relatively The copending application of Charles M. Blair, dilute brine, which constitutes the continuous Jr. and Charles Clinton Rogers, Jr., Serial No. phase of the emulsion. As far as I am aware, 179,472, filed December 13, 1937, discloses that 25 the expressions “cut oil', 'roily oil', etc. com these unusual emulsions may be separated into monly used to designate conventional water-in their component parts of oil and water by treat oil emulsions, are not used to designate or refer illent with a minimal concentration of a multi to the peculiar oil-in-Water petroleum emulsions poiar, substantially un-ionized hydrophile colloid. 30 which my improved process is capable of Success I have discovered that these unique emulsions 30 fully treating to recover the oil contained in having these peculiar characteristics can be Sae. treated more rapidly and at a lower temperature Although such peculiar emulsions are recog and with the separation of Somewhat clearer oil nized technically as being of the oil-in-water and water phases, if they are treated with a mix 35 type, their physical-chemical constitution is only ture containing a multipolar, Substantially un 35 partially understood. It is recognized that one ionized hydrophile colloid of the kind hereinafter may have emulsions of the oil-in-water type in described, and an electrolyte of the kind herein which the dispersed phase is present to the ex after described. tent of a few tenths of 1%, or less, in which the Effective hydrophile colloids which may be used stability of the emulsion appears to be predicated in the mixture employed as the treating agent or 40 On factors other than the presence of a sig dealsifying agent of my process, are those which nificant amount of a conventional emulsifier; give rise only to very small electrical effects when that is, factors such as particle size, electric adsorbed at interfaces. In general, they are charge, etc. It is also known that emulsions of either the weakly ionized, amphioteric, or un the oil-in-water type may exist in which the ionized hydrophile colloids, and are further char 45 - dispersed phase represents a significant propor acterized by the fact that they contain a multi tion of the total emulsion; for instance, from 3% plicity of polar groups, such as -COOH,-COOR, to 5% of the emulsion, up to 60% to 70%, or R-O-R, -OH, -NH2, -NRH, NR2 -CO-NH-, etc., even more, provided that there is a protective where R is a univalent organic radical. It 50 colloid or conventional emulsifying agent present. may happen that all the polar groups which are 50 However, as far as I am aware, technologists have present in a hydrophile colloid are of the same not been confronted with a type of oil-in-Water kind, or they may be of substantially different emulsion in which there was dispersed a signifi kinds, or they may be of several varieties which cant portion of the oily phase in What appears to are generally related to each other. Such hydro SS be a substantially complete absence of a protec phile colloids are characterized by the fact that 55 2 2,159,312 the polar groups are not segregated at a particu loid of the kind previously described are: NaCl, lar point but are distributed more or leSS uni KC, HCl, H2SO4, HNO3, CaCl2, MgCl2, Ca(NO3)2, formly throughout the molecule, so that their FeCl3, Th(NO3)4, Ce(SO4)2, Mg(NO3)2, MgSO4, Solution or sol contains a body having what ap Al2(SO4)3, AlCl3, FeSO4, Fe(NO3)3, methylene pears to be a more or less uniformly hydrated Sur blue, fuchsin, many other basic dyes, perlargon face, although the chemical structure of the idin chloride, cetyl pyridinium bromide, toluidine molecule indicates that the hydrated Zones must hydrochloride, diphenyl guanidine hydrochlo be interrupted or alternated by non-hydrated ride, benzyl pyridinium chloride, many other Zones or groups of non-polar or hydrophobe char Water Soluble Salts of strong or relatively strong O acter. organic bases of moderately high molecular 0 This feature of distributed hydration along weight, etc. Because of their low cost and with the concomitant property of distributed availability, salts of alkaline earth metals and hydrophobe characteristics, distinguishes these of iron, such as CaCl2, MgCl2, MgSO4, BaCl2, and materials from other hydrophile colloids such as FeSO4, are usually employed. 5 soaps, the molecules of which are considered as The ratio of the hydrophile colloids to elec being made up of one definitely polar hydrated trolyte which should be added to a given emul 15 end, and one definitely non-polar, non-hydrated sion to give the optimum results, will depend end. Inasmuch as these hydrophile colloids Con Somewhat upon the emulsion, the hydrophile tain more than one polar group, they may be colloid, and the electrolyte employed. Some referred to as 'multipolar' and may be defined as times optimum results are obtained when ten 20 the multipolar, substantially un-ionized type of times as much hydrophila colloid is used as elec hydrophile colloid. The expression “substantial trolyte. In other cases, best results are obtained ly un-ionized' as herein used is intended to in when only one-tenth or one-twentieth or even clude the previously described hydrophile colloids one-hundredth as much hydrophile Colloid as 2 5 which give rise to minimal electrical effects. electrolyte is used. When the hydrophile colloid 25 The colloidal dispersions of these hydrophile used is glue and when the electrolyte used is colloids are relatively non-sensitive to electro CaCl2, it has been found that the mixture con lytes, and they often form gels or very viscous, taining one part of glue to four parts of CaCl2 aqueous dispersions. Materials such as Soaps, is effective on a number of emulsions. For the 30 highly ionized dyes, and other relatively strong treatment of any particular emulsion, the proper 30 coiloidal electrolytes, high molecular weight or proportions of hydrophile colloid and electrolyte ganic sulfates and Sulfonates, are not included to employ may be determined by a few simple in this classification. Examples of materials tests. Taking glue and calcium chloride as an having the properties which make them suitable example of a mixture to be tested, the test may for use as a demulsifying agent for breaking the be made as follows: 35. peculiar oil-in-water type emulsion previously Prepare five different solutions in water, all described are: glue, gelatin, casein, starch, albu containing the same total percentage Weight of min, tannin, dextrin, methyl cellulose, Water Sol material, but with one solution containing ten uble ethyl cellulose, Prosopis juliflord exudate, times as much glue as calcium chloride, another 40 gun arabic, many other water dispersible guns, containing five times as much glue as Calcium water dispersible urea-aldehyde resins, etc. In chloride, another containing equal Weights of 40, some instances, a mixture of two or more of Such glue and calcium chloride, one containing five materials or colloids may be more effective than times as much calcium, chloride as glue, and an one alone. It is recognized that Some of these other containing ten times as much calcium 45 products, such as starch, glue, or the like, pro chloride as glue. These stock Solutions may be duce degradation products which are similar in kept satisfactorily by the addition of a Small 45 colloidal nature to their parent material. Obvi ously, such degradation products could be used amount of the proper preservative. Then add with equal effectiveness. In order to designate 100 mls, of the emulsion, on which these mix only the desired type of hydrophile colloid and tures are to be tested, to each of 25 six-ounce 50 bottles. Take one of the stock Solutions and 50 to exclude the unsuitable type, I will refer to the add sufficient of this solution to one of the type employed as being Substantially un-ionized. emulsion samples to give a concentration of one The expression “substantially un-ionized' is part of the colloid-electrolyte mixture to about meant to include the type which is un-ionized 100,000 parts of emulsion. To other samples of 55 or weakly ionized or amphoteric. emulsion, add increasing amounts of this stock 55. Electrolytes which have been found to be the solution, so as to have bottles containing a ratio most effective when used with the hydrophile of colloid-electrolyte mixture of one part to 50,- colloids described above are those containing 000 parts of emulsion, one part to 25,000 parts highly charged or relatively highly adsorbable of emulsion, one part to 10,000 parts of emul 60 cations, and may be either inorganic or organic sion, and one part to 5,000 parts of emulsion. 60 compounds. In some cases, compounds contain Add amounts of each of the other stock Solutions ing cations such as Na-- or H--, bearing only to Samples of emulsion in the same imanner to one charge, when added to the emulsion de give the same ratios of colloid-electrolyte mix scribed, along with a hydrophile colloid, have ture to emulsion. After this has been done, 65 been found to give faster and cleaner separation shake all of the bottles for about two or three 65 of phases than can be obtained with a hydro minutes and allow to Stand. It will be found phile colloid alone. However, among inorganic that one or two of the bottles containing a par electrolytes, it has been found that compounds ticular One of the Stock Solutions will show a containing divalent, trivalent, tetra Valent or quicker and cleaner separation of phases. Fur 70 higher valence cations, usually are the most ef ther tests should then be made in a similar man 70 fective. Organic compounds containing a large ner, using this particular stock solution and highly adsorbable cation, usually are quite effec other freshly made stock solutions containing tive in this mixture, regardless of valence. ratios of hydrophile colloid to electrolyte which Examples of electrolytes which I have found to vary closely on either side of this one. By this 75 be suitable for admixture with a hydrophile col elimination, it will be possible to select a ratio 75 2,159,812 3 giving the optimum separation and also to Select oil-in-water type crude petroleum emulsions that the proper concentration in which this material are substantially free from usual emulsifying should be added to the emulsion. The proper agents and in which the dispersed phase repre ratio of hydrophile colloid to electrolyte in other Sents a significant proportion of the total emul mixtures containing ingredients different from Sion, characterized by Subjecting the emulsion to these may be determined in the same manner. the action of a demulsifier comprising (a) a mul The mixture that constitutes the preferred re ti-polar, Substantially un-ionized colloid of dis agent or demulsifying agent of my process may tributed hydrophilic character, and (b) an elec be made as follows: In a container, place 45 trolyte derived from a polyvalent metal; and 0 pounds of glue or commercial gelatin, and 91 characterized by the fact that the ratios of (a) to 0 pounds of Water. Warm this container and stir (b) are within the range of 10 to 1 and 1 to 100, the contents until a homogeneous mixture is the said demulsifier being used in a ratio of less obtained. In another container place 213 pounds than One part of demulsifier to 1,000 parts of of CaCl2.2H2O and 193 pounds of water, and stir emulsion. 5 until the CaCl2.2H2O has gone completely into 5. A process for breaking naturally occurring 5 solution. Then pour the glue or commercial oil-in-water type crude petroleum emulsions that gelatin Solution prepared in the first container are substantially free from usual emulsifying into the calcium chloride solution and stir until a agents and in which the dispersed phase repre homogeneous mixture is obtained. Then add Sents a significant proportion of the total emul 20 five pounds of methyl salicylate or five pounds of Sion, characterized by subjecting the emulsion to 28 a concentrated zinc chioride solution which acts the action of a demulsifier comprising (a) a mull as a preservative. Any compatible coloring mat ti-polar, Substantially un-ionized colloid of dis ter or odorant may be added, if desired. In Sonne tributed hydrophilic character, and (b) an elec cases, alcohol, ether, or other inert organic liquids trolyte derived from an alkaline earth metal; and 25 may be added to lower the viscosity and improve characterized by the fact that ratios of (a) to (b) 25 the physical properties of the material. are within the range of 10 to 1 and 1 to 100, the In using the above described reagent to treat Said demulsifier being used in a ratio of less than or break the peculiar oil-in-water type emulsion one part of demulsifier to 1,000 parts of emulsion. previously described, the reagent is added to the 6. A process for breaking naturally occurring 30 emulsion to be treated in the same manner and oil-in-Water type crude petroleum emulsions that 30 by the procedure commonly employed in processes are substantially free from usual emulsifying in which demulsifying agents are used for treat agents and in which the dispersed phase repre ment of conventional oil field emulsions. It Sents a significant proportion of the total emul Should be added in approximately the amount sion, characterized by subjecting the emulsion to 35 required as determined by the test given above, the action of a demulsifier comprising (a) a mul 35 but in general a reasonable excess over this ti-polar, Substantially un-ionized carbohydrate amount is not objectionable in any way other type colloid of distributed hydrophilic character, than that the cost of treating the emulsion is and (b) an electrolyte derived from an alkaline thereby increased. earth metal; and characterized by the fact that 40 Having thus described my invention, what I ratios of (a) to (b) are within the range of 10 to 40 claim as new and desire to Secure by Letters Pat 1 and 1 to 100, the Said demulsifier being used in ent is: a ratio of less than one part of demulsifier to 1. A process for breaking naturally occurring 1,000 parts of emulsion. oil-in-water type crude petroleum emulsions that 7. A process for breaking naturally occurring 45 are Substantially free from usual ennulsifying oil-in-Water type crude petroleum emulsions that 45 agents and in which the dispersed phase repre are substantially free from usual emulsifying sents a significant proportion of the total emul agents and in which the dispersed phase repre sion, characterized by subjecting the emulsion to Sents a Significant proportion of the total emul the action of a demulsifier comprising (a) a multi Sion, characterized by Suibjecting the emulsion to 50 polar, substantially un-ionized colloid of distrib the action of a demulsifier comprising (a) a mull 50 uted hydrophilic character, and (b) an electro ti-polar substantially un-ionized, naturally oc lyte; and characterized by the fact that ratios of Curring gum type colloid of distributed hydro (d) to (b) are within the range of 10 to 1 and 1 philic character, and (b) an electrolyte derived to 100, the said demulsifier being used in a ratio from an alkaline earth metal; and characterized 55 of less than one part of demulsifier to 1,000 parts by the fact that ratios of (a) to (b) are Within 55 of emulsion. the range of 10 to 1 and 1 to 100, the said demul 2. A process of the kind described in claim 1, in sifier being used in a ratio of less than one part which the minimum amount of demulsifier re of demulsifier to 1,000 parts of emulsion. quired to effect the separation of the component 8. A process for breaking naturally occurring 60 parts of the emulsion, is added to the emulsion. oil-in-water type crude petroleum emulsions that 60 3. A process for breaking naturally occurring are substantially free from usual emulsifying oil-in-water type crude petroleum emulsions agents and in which the dispersed phase repre that are substantially free from usual emulsify sents a Significant proportion of the total emull ing agents and in which the dispersed phase rep sion, characterized by subjecting the emulsion to 65 resents a significant proportion of the total emul the action of a demulsifier comprising (a) a mull 65 sion, characterized by subjecting the emulsion to ti-polar, substantially un-ionized, protein type the action of a demulsifier comprising (a) a mud colloid of distributed hydrophilic character, and ti-polar, substantially un-ionized colloid of dis (b) an electrolyte derived from an alkaline earth tributed hydrophilic character, and (b) an in metal; and characterized by the fact that ratios 70 organic electrolyte; and characterized by the fact of (a) to (b) are within the range of 10 to 1 and 70 that ratios of (a) to (b) are within the range of 1 to 100, the said demulsifier being used in a ratio 10 to 1 and 1 to 100, the said demulsifier being of less than one part of demulsifier to 1,000 parts used in a ratio of less than one part of demulsifier of emulsion. to 1,000 parts of emulsion. 9. A process for breaking naturally occurring 75 4. A process for breaking naturally occurring oil-in-water type crude petroleum emulsions that 75 4. 2,159,812 are Substantially free from usual emulsifying (b) calcium chloride; and characterized by the agents and in which the dispersed phase repre fact that ratios of (a) to (b) are within the range sents a significant proportion of the total emul of 10 to 1 and i to 10, the said demulsifier being sion, characterized by subjecting the emulsion to used in a ratio of less than one part of demulsifier the action of a demulsifier comprising (d) a mul to 1,000 parts of emulsion. ti-polar, Substantially un-ionized, protein type 11. A process for breaking naturally occurring colloid of distributed hydrophilic character, and oil-in-water type crude petroleum emulsions that (b) calcium chloride; and characterized by the are substantially free from usual emulsifying fact that ratios of (a) to (b) are within the range agents and in which the dispersed phase repre 0 of 10 to 1 and 1 to 100, the said demulsifier being Sents a significant proportion of the total emul 0 used in a ratio of less than one part of demulsifier sion, characterized by subjecting the emulsion to to 1,000 parts of emulsion. the action of a demulsifier comprising (d) glue 10. A process for breaking naturally occurring and (b) calcium chloride; and characterized by oil-in-water type crude petroleum emulsions that the fact that ratios of (a) to (b) are within the 15 are substantially free from usual emulsifying range of 10 to 1 and 1 to 10, to which has been 5 agents and in which the dispersed phase repre added an appreciable amount of a suitable pre Sents a Significant proportion of the total emull servative, the said demulsifier being used in a sion, characterized by subjecting the emulsion to ratio of less than one part of demulsifier to 1,000 the action of a demulsifier comprising (d) a mu parts of emulsion. 20 ti-polar, Substantially un-ionized, protein type CHARLES M. BLAIR, JR. 20 colloid of distributed hydrophilic character, and CERTIFICATE OF CORRECTION. Patent No. 2,159,312. May 25, 1959. CHARLES M. BLAIR, JR. It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page l, sec ond column, line l8, in the formula, after "NR" and before -CO-NH- in sert a comma; line 5), for the word "generally" read generically; page 2, first column, line 39, for "juliflord" read uliflora; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office. Signed and sealed this lith day of July, A. D. 1939.

Henry Wan Arsdale (Seal) Acting Commissioner of Patents. CERTIFICATE OF CORRECTION. Patent No. 2,159,312. May 23, 1939. CHARLES M. BLAIR, JR. It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page l, sec Ond column line 218, in the formula, after "NR." and before -CO-NH- in sert a comma; line 5), for the word "generally" read generically; page 2, first column, line 39, for "juliflord" read juliflora; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office. Signed and sealed this lith day of July, A. D. 1939.

Henry Wan Arsdale (Seal) Acting Commissioner of Patents.