CA1119794A

CA1119794A - Method and installation for flooding petroleum wells and oil-sands

Info

Publication number: CA1119794A
Application number: CA000321267A
Authority: CA
Inventors: Fritz Wagner; Peter Rapp; Hans Bock; Walter Lindorfer; Walther Schulz; Wilhelm Gebetsberger
Original assignee: Helmholtz Zentrum fuer Infektionsforschung HZI GmbH; Wintershall AG
Current assignee: Helmholtz Zentrum fuer Infektionsforschung HZI GmbH; Wintershall AG
Priority date: 1978-02-11
Filing date: 1979-02-12
Publication date: 1982-03-16
Also published as: DE2805823A1; RO85902A; RO85902B; BR7900826A; AT365738B; FR2422715A1; NL7900992A; DE2805823C3; NL171736B; NL171736C; SU1105125A3; FR2422715B1; DE2805823B2; AR225608A1; ATA53479A

Abstract

Abstract of the Disclosure The invention relates to a method of flooding petroleum wells and oil sands using a non-ionic surface active agent in water as the flooding medium. In a gasified bio-reactor there are produced glycolipids from a culture of micro-organisms using hydrocarbons and added nutrients under specified conditions. The formed glycolipids are separated from the cellular mass and the aqueous phase, with the formed glycolipids dispersed therein, is used as flooding medium or as an ingredient of the flooding medium.

Description

The present invention relates to a process for recovery of oil frQm oil wells and oil sands and an apparatus for carrying out that process.
Our copending Canadian Patent Application Serial No. 288,721, filed February 12, 1979, describes a method for flooding petroleum wells using non-ionic, aqueous dispersions of surface active agents which are forced as floodingagents into wells, without any pre-flushing liquid. These surface active agents are glycolipids of specific structures which are obtained by means of micro-organisms. Some of the glycolipids contain a disaccharide portion which consistsof trehalose, cellobiose, mal-tose, isomaltose. The disaccharide portion may bear aIkyl substituents Rl to R3 which may be unbranched, branchea, saturated, unsat-urated, hydroxylated. Other non-ionic, surface active agents may be added in order to stabilize the aqueous dispersion. The dispersions can be produced with the oil-well water, for example. The concentration of the surface active agent should be between 0~01 and 5 g/l.
Canadian Patent Application Serial No. 288,721 also describes glyco-lipids in ~hich a monosaccharide portion consists of glucose, fructose, mannose,galactose. me monosaccharide portion may bear as substituents aIkyl groups R
and R5 which may also ke unbranched, branched, saturated, unsaturated, hydroxy-lated.
~urther, Canadian Patent Application Serial No. 288,721 de~cribes ~ glycolipids in which an oligosacchari~e part consists of amylopectin, amylose, .: cellulose, dextran, chitin~ yeast glucan~ pullulan or glycogen. m e oligo-saccharide portion may bear as substituents alkyl groups Rl and. R3 which may also be unbranched, branched~ saturated, unsaturated, hydroxylated.
; me method of the above-mentioned patent application has the advantage that the surface active substances introduced into the well with the aqueous dispersion produce no precipitation prodwts created by reaction with any aIkaline-':

earth and iron ions in the well, so that they do not lead to blockages in the well. Further, the viscosity of the flooding agent is not increased by these surface active substances, so that excessive injec~ion pressure is unnecessary.
The present invention uses, for flooding petroleum hydrocarbons out of oil wells and oil sands, dispersions of non-ionic, surface active glycolipids, preferably produced by using mixtures of hydrocarbons as the source of carbon-feed for the glycolipid-producing micro-organism.
According to one aspect of the present invention, there is provided ., a process for the recovery of oil from an oil well or oil sands, which process comprises (1) growing a culkure of a micro-organism in an aqueous medium and under aerobic conditions, with the addition of hydrocarbons as an organic sourceof carbon, inorganic nutrients and air or oxygen-enriched air, at a temperature between 20 and 50C and at a constant pH value between 3 and 9, the concentration of hydrocarbons in the aqueous medium being from 1 to 35% by volume, to produce a glycolipid; (2) separating the glycolipid from the mass of micro-organism by ~ thermal, pH or osmotic shock or by extraction with a homopolar organic solvent ;~ followed by solvent evaporation and (3) flooding the oil well or oil sands with the separated glycolipid as flooding agent or as a component in a flooding agentin the recovery of oil from the oil well or oil sands.
According to another aspect of the invention there is provided an ` apparatus for use in preparing a solution or dispersion of glycolipid for use in oil extraction comprising in sequence a first vessel which may act as a first . .
bio-reactor for semi-continuous or continuous aerobic growth of a submerged cul-ture of a micro-organism, a second vessel which may act as a first separator forseparating unused carbon-feed source from the culture solution or as a separatorto separate cellular mass rom a liquid phase of the culture solution, a third vessel which may act as a second bio-reactor in which a thermal, pH or osmotic .r~ .
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shock can be imparted to the culture solution or as an extractor for solvent extraction of glycolipid from the cellular mass and a Eourth vessel which may act as a second separator for separating the cellular mass from the liquid pha æ
of the culture solution or as a vaporizer to remove solvent from the glycolipid solution.
The method according to the invention is carried out in two stages.
In the first stage, glycolipids are produced initially by micro-organisms under specific parameters in a se~i-continuous or continuous process; in the second stage, these are separated fram the cellular mass by thermal-, pH- or os~otic-shock or by means of homopolar organic solvents.
Thus the ~ethod according to the invention involves producing glyco-lipids biologically by using mixtures of alkanes as carbon-feed source for the micro-organism, and of using the glycolipids to improve the yield of oil from wells and oil sands.
The invention is based upon Canadian Patent ApplicRtion Serial No 288,721 which descrikes the prior art used to ~ncrease the yield of petroleum by - floodtng the well, According to this application, it is proposed to use micro emulsions with surfactant or co-surfactant means for the secondary recovery of petroleum, , The aqueous dispersion used in the method according to Canadian Patent `~ Application Serial No. 288,721 is a non-ionic surface active substance which pro-duces no precipitat;~on in the well. Since the non~ionic surface active glyco-lipid does not affect the viscosity of the flooding agent, excessive injection pressures are unnecessary.
In one preferred em~odDment of the present invention the water and the crude oil from the well æ e separated in a separator~ Some of the crude oil is ; passed to the bio-reactor in the ~irst stage, into which are also introduced ' `
~'` ' hydrocarbons, preferably, n-alkanes, a nutrient-salt solution, water which may be from the oil well, and air or o~ygen-enriched air, while waste air is removed.
The phase mix is introduced into a separator where the unused residual oil is separated, after which the said phase mix passes to a second-stage bio-reactor where, as described by way of example, the thermal-, pH- or osmotic-shock, for obtaining a higher concentration of glycolipids, is carried out. In the follow-ing separator, the oil-free culture suspension is separated into the cellular mass, which is removed and may possibly be wholly or partially recycled to the ; growing submerged culture, and the aqueous phase containing the glycolipid. me latter is converted into a stable dispersion, in an agitator-mixer, by means of dissolving and/or dispersing agents, and is metered into the flooding water or is introduced directly into the flooding drill-hole.
As a modification of this e~odiment, the cellular mass is separated in a separator, fro~ the aqueous phase and the residual oil, after which the cellular mass is removed in an extractor, with fresh or recycled extraction a~ents. A crude e~tract is obtained in an evaporator and is similarly dispersed in a mixer.
ln one aspect of the invent~on the micro-organism used is of the species nocardia rhodocrous, which yields a glycolipid of form~lla I

OH

O=C - ¢H-CH-(CH2) -CH3 OH

fH2(CH2)m CH3 fH2-O-C-cH-$H-(cH2)n-cH3 H~ H ~ - (CH2)m-CH3 L H OH
O

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wherein m i5 an integer from 8 to 9 and n is an integer from 18 to 20. The hydrocarbon feed can be either a mixture of C12 to Clg n-alkanes or crude oil from the oil well or oil sands.
In another aspect of the invention the micro-organism used is of the species mycobacterium phlei, which yields a glycolipid of formula II

OH
o=C - cH-cEl-(cH2)n-cH=cH-(cH2)n-cEl3 CH2 (CH2)m~CH3 CH2-0-C-CH-CH- (CEI2) ~I=CH

~ ~H H~ (CH2)m-CH3 CEI3 HO~/ lo\~H
H OH - . O_~

wherein-m is an integer ~.rom 2Q t~ 22 and n is an ~nteger ~rom 14 to 17. The hydrocarhon feed can be e~ther a ~ixture of C8 to C23 n-a~kanes or cxude oil from the oil well or o~l sands.
When the hylrocarkon feed is crude oi1 from the oil ~ell or oil sands, it IS preferred that it IS fed to tHe micro-or~anism at a concentration by vol-ume in ~atex of from 5 to 35%. The water may be well water or fresh water~
When the hydrocar~on feed i~s a Cg to C2g alkane ~t is preferred. that the concen-tration is fxom 5 to 25% by v~lume.
m e culturing of the micro-organism can be carried out se~mi-continuously or continu~usly and with or without agitation~ In a preferred embodiment the process is carried out continuously and the contents of the first stage pass ' - 5 _ ..... . . .

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through the first stage reactor at a flow rate of 0,1 to 0.7 vol/vol/hr and th~-ough the second stage reactor.
The glycolipid is separated from the culture mass either by extraction with a hcmopolar oxganic solvent, for example n-hexane, or by means of thermal, pH
or osmotic shock. If thermal shock is used, it is preferred that the first stage is carried out at a temperature between 25 and 45C and that the thermal shock in the second stage is carried out at a temperature between 35 and 75C. If osmotic shock is used it is preerred that in the second stage from 50 to 2Q0% by volume of a solution of either well water or fresh water containing at least 10% by weight of salt is added. If pH shock is used it is preferred that in the first stage of pH between 4 and 8 is used and in the second stage ffhe pH is adjusted to between 8 and 10.
In addttion to hydrocarbons nutrients are fed to the micro-organism, suitably containing ammonium salts, nitrate salts or urea salts as sources of nit-rogen. Inorganic salts, yeast extract and meat extract can also be added.
Pir or oxygen-enriched air, preferably having an oxygen content between 20 and 60% by volume is supplied to the f~rst and second stage reactors. A suit-able aeration rate i`s frcm 0.1 to 2.0 v~l/vol/min and a rate of from 0.5 to 1 5 vol/vol/min is preferred.

The apparatus for the execution of the method of the invention is also s~own in Figures 1 and 2. Examples 1 to 4 describ~ the execution of the me-thod.
EXample 5 deals WIt~ the production of a stable disperslon. Examples 6 and 7 cover the technical advance achieved by tHe ~mproved yield of petroleum.
E~ample 1 - In the first stage of the process, a bio-reactor, e~u~pped with a tur~
blne agitator, is filled with 10 1 ~l=litres) of nutrient solution of the follow-4~2 P4 15 g, K112PO4 5 g, K2HPO4.3H2O 10 g, Na2HPO 2H O 5 g MgS04.7H20 1 g, KCl 1 g dissolved in 10 1 of flooding water and con-taining 900 g of crude oil .
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and 200 g of an n-alkane mi~ture of a chain length between C8 and C24. This is inoculated with an inoculum consisting of 100 ml of a nocardia rhodochrous sp.
culture, and is grown at 30C, at an aeration rate of 0,5 V/Y/m~ and 400 r.p.m.
During its growth, the submerged culture is automatically adjusted to a pH value of 7,0, in a pH control station, by the addition o:E a 12% by volume ammonia solution. After 26 h, a change is made to continuous processing, by metering-in the nutrient medium at a flow rate of 0,4 l/h. At the same time, the culture suspension from this bio-reactor is passed, at the same rate of flow, to a ; separator for the removal of unused crude oil, the culture suspension separated from the residual oil being pumped continuously into the second bio-reactor.
; In the second stage of the process, the second bio-reactor operates at a constant working volume of 20 1, at a temperature of 60C, to produce thermal shock, at an aeration rate of 0,2 Vol./VOL./min., a r.p.m. of 600, and at a pH value of 7,0 automatically adjusted by the addition of a 12% by volume ammonia solution. The cellular mass is removed by centrifuging from the culture ; suspension flowing continuously at a rate of 4 l/h, and the aqueous phase, which contains glycolipides, of the composition given in Example 4, at a concentration of 600 mg/l, is used directly for the produc~.ion of a stable aqueous suspension which is added to the flooding water.
: 20 E~
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In the first stage of the process, a 340 l bio-reactor, equipped with a Kaplan turbine and a cylindrical guide, is filled with 200 l of nutrient solution of the following composition: urea 400 g, KH PO 200 g, K HPO .3H O
400 g, Na2HPO4. 2H20 200 g, KCl 100 g, MgSO4. 7H2O 40 g, dissolved in 200 l of flooding water and 2 kg of n-alkane mixture of a chain length between C12 and Clg. This is inoculated with an inoculum consisting of a nocardia rhodocrous sp. culture, and is grown at 30C, an aeration rate of 0,5 V/V/m, and an r.p.m.

~, ' ', of 1200. During growth, the submerged culture is automaticall~ held at a pH
value of 7.0, by means of a pH control s~ation, by the addition of a 25% by volume ammonia solution. After 26 h a change is made to continuous processing by adding the nutrient medium at a flow rate of 0,3 l/h. At t~e same time, the culture suspension from this bio-reactor is passed, at the same rate of flow, directly into a loop reactor equipped with a binary jet nozzle and operating at a constant working volume of 600 1.
In the second stage of the process, the bio-reactor is operated at ;
30C, an air-flow of 18 m3/h, a rotational frequency of 320/h, and with a pH
` 10 value of 9,5 kept constant, with a pH control station, by the addition of a 25% `
by volume ammonia solution, thus initiating pH shock. The cellular mass is separated, by continuous centrifuging, from the culture suspension which flows continuously at a rate of 60 l/h. The aqueous phase, which contains glycolipidesof the composition given in Example 4, at a concentration of 650 mg/l, is used -~
; direc~ly to produce a stable aqueous suspension, and is added to the flooding water.
7 Example 3.
In the first stage of the process, a 340 l bio-reactor, equipped with a Kaplan turbine and a cylindrical guide, is filled with 200 1 of nutrient solution of the following composition: urea 400 g~

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KH2PO4 200 g, K2HPO4-3H2O 400 g, Na2HPO4.2H2O 200 g, KCl 100 g, MgSO4.7H2O

40 g, yeast extract 20 g, dissolved in 200 1 of fresh water and 4 kg of n- -alkane mixture with a chain length of C8 to C24. This is inoculated with 10 1 of an inoculum consisting of a mycobacterium phlei culture, and is grown at 37 C, an aeration rate of llO V/V/m, and an r.p.m. of 1200. During growth, the submerged culture is automatically adjusted to a pH value of 6,8 with a pH control station, by the addition of a 25% by volume ammonia solution.
After 20 h, 160 1 of the submerged culture are pumped into a second bio-reactor having a working volume of 500 1 and equipped with a ~urbine agitator. Growth is continued in the second stage of the process for lO h under the same condi-tions as in the first stage. Therea:Eter, 200 1 of (oil) well-water, having a salt content of 10% by weight, are added, and intensive stirring is continued for another 4 h.
The addition of salty well-water produces osmotic shock, and the glycolipides are released from the cellular mass into the culture solution.
After the said cellular mass has been separated, the culture filtrate contains 124,8 g of glycolipides having the following structures:

i) OH
O=C - C~H-cH-~cH2)l7-cH=cH-~cH2)l7 3 O [I 2)21 O OH
CH2 3 fH2-O-C-ICH-CH-(CH2)17-CH=~CH
I ~I 2)21 ~1CH2)17 H~ - ~1 H ~ -O ~H 3 3 H ~ HO ~ _H~
H OH H OH
O

Yield: 74,88 g = 60%, related to total liquides.

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O=C - C,H-CH-(CH2)16-CH=CH-CH ~CH2)1~ 3 (I 2 23 0 OH
CH2 3 CH2-0-C-C,H-)}1 (CH2)16 CH-CH3 H~--O~H H~o H3 ~CH3)14 HO ~ H0 ~ ~
H OH - O ~ -Yield: 49,92 g = 40%, related to total lipides.
The mixture of these glycolipides from structures 1 and 2 is used directl~ to produce a stable aqueous dispersion which is added to the flood-ing water.
` After 160 1 of the submerged culture have been removed from the ;~ first-stage bio-reactor, the remaining 40 1 of submerged culture are mi~ed with 160 1 of nutrient-salt solution. This is grown for ;
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~:, 20 h under the condi~ions in stage 1, and glycolipidescontinue to be obtained semi-continuously in the same way. ' Example 4.
In the first stage of the process, a 14 1 bio-reactor, equipped with a Kaplan turbine and a cylindrical guide, is filled with 10 1 of nutrient solu-tion of the following composition: (NH4)2HP04 15 g, KH2P04 5 g, K2HP04.3H20 10 g, Na2HPO4.2H2O 5 g, MgSO4.7H2O 1 g, KCl 1 g, dissolved in 10 1 of flooding - water and with 100 g of n-alkane mixture having a chain length of C12 to C19.
This is sterili~ed at 121C and, after cooling to 30C, is inoculated with an inoculum consisting of 100 ml of a nocardia rhodocrous sp.. and this is grown at 30 C, with an aeration rate of 0,5 V/V/m and an r.p.m. of 1200. During growth, a pH value of 7,0 is maintained in the submerged culture automatically, by means of a pH control station, by adding a 12% ammonia solution. ~rowth comes to an end after 26 hours.
Thereafter, the resulting cellular mass, corresponding to 85 g of ` dry mass, is separated from the aqueous culture solution in a continuous centri-fuge running at 15000 g (? r.p.m.~. In order to isolate the glycolipides, the ~
cellular mass containing them is thrice ex~racted, in the second stage of the ~`
process, each time with 500 ml of n-hexane~ at 20C, the combined n-hexane extract is concentrated in vacuo, and this crude extract is adsorbed in a sili-cagel col D having a 200 ml capacity. Tlle remaining 15 g of n-alkane mixture is washed with 250 ml of chloroform, after which the glycolipides are washed ; with 200 ml of acetone. The eluate is then concentrated in vacuo and the glycoplipides, still contaminated with a yellow pigment, are cleaned by rechrom-atography with chloroform/
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:' ' ~' :' ` , acetone elutriating agents, in a 2 : 1 vol/vol ratio, and acetone.
This produces 7,2 g of glycolipides of the following structures I:
1~ OH
O=C - CH-CH-~CH 3 -CH
O (CH2)9 o OH

2 CH2-0-c-c~H-)H-(cH2)2l 3 H~ ~1 ~1~ O\H 3 HO~ ~ HO~

The yield amounts ~o 2,88 g = 40%, related to total glycolipides.
2) IOH
O=C CH-CH- ~CH2) 18-CH3 CH cH2-O- OH
7H2 3 ¦ (I 2311 ~
H'H~ O~H H~ O~H 3 HO~ LHO\~j~
I H OH O
The yield amounts to 2,16 g = 30%, related to total glycolipides.

3) OH
O=~C - CH-CH-(CH2)20 CH3 ~ ~l 2 9 0 OH
~ 7H2 3 CH2-0-C-c,H-cH-(cH2)20 3 11~0~l H~ O HC 3 HO~H~ HO\~
H OH o H OH I
, The yield amounts to 2,16 g = 30%, related to total gl~colipides.

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The aqueous dispersions are obtained in practice from the crude extract from the n-hexane extraction, and are added to the flooding water.
Example 5 .
50 mg of glycolipide, obtained in the crude extract process des-cribed in Example 4, are added to 1 litre of nutrient-salt solution and are treated ultrasonically ~25 kH) for 30 minutes with simultaneous stirring.
- Ihis produces a milky-looking dispersion which undergoes no change even after ~ Gi// r~e~ r ~~ lengthy standing. As compared with crude oil from the Duste-Valendis.w41~, the said dispersion has an interfacial tension of about 5 mN/m which remains constant for more than 100 h. The dispersion thus tested is used as a flood-ing agent to impro~e the yield of oil in the flooding test according to Ex-ample 6.
; Example 6 A flooding core of Bentheim sandstone, 5,2 cm is diameter and 27 cm in length, has a 19,4% porosity and a pore volume of 110 ml. Its permeability to water is 1600 millidarcys. The said core is impregnated with 98,9 ml of eS~ V~ 1~
crude oil from the Duste-Valendis ~ viscosity at 40C = 26,3 mPa s) and 11,1 ml of salt water ~viscosity at 40C = 0,9 mPa s) containing ~8 g/l of CaC12, 9,6 g/l o~ MgC12 and 102 g/l of NaCl; this produces an initial oil satusation of 89.9~.

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" "' ' ' ~ ' ' ' ' ' At a temperature of 40 C, the core is flushed with 1143 ml of salt water. This produces 40,9 ml of oil, corresponding to an initial oil content of 41,4%. The oil saturation now amounts to only 52,7%. Thereafter, the dispersion produced according to Example 5 is flushed with 749 ml of the dispersion produced according to Example 5, which produces a further 18,9 ml of ; oil. The yield has thus increased to 60,5%, while the oil saturation of the ; core has decreased to 35,5%. ~lushing with 1440 ml of salt water after dis-persion produces a further 10,5 ml of oil, and this increases the overall yield ; to 71,1%; the residual oil saturation in the core thereafter amounts to only 26%. Flooding with the dispersion therefore produces another 29m4 ml of 51%
from the oil in the core.
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24 mg of the aqueous phase ~40 ml) containing glycolipide, obtained according to Example 1, are added to 960 ml of nu~rient-salt solution and this is treated ultrasonically (25 kH) for 30 minutes with simultaneous stirring.
This produces a milky dispersion which under~oes no change, even after lengthy standing. This dispersion is ~ed to flush a rock core made of Bentheim sand-stone which is 5,2 cm in diameter, 27 cm in length, has 19,1% porosity and a pore volume of 108 ml. Permeability to water is 1700 millidarcys. The core is impregnated with 98,9 ml of crude oil from the Duste-Valendis oil reservoir (viscosity at 40C = 40 mPa s) and 9,1 ml of salt water (viscosity at 40~ = 0,9 mPa s) containing 28 g/l of CaC12, 9,6 g/l of MgC12 and 102 g/l NaCl; this pro-duces an initial oil saturation of 91,6%. At a temperature of 40C, the core is flushed with 1264 ml of salt water, whereby 44,5 ml of oil are recovered, ' '`.',' ' , .. . . . ,, ~, , `

.; ' corresponding to a yield of 45%. The oil saturation now amounts to only 50.4%.
~lushing is then carried out with 750 ~1 of the dispersion, which produces a furtHer 22 ml of oil. m is increases the yield of oil to 67.2%, and the residual oil saturation is reduced to 30%. After re-flushing with 1120 ml of salt water, only another 0.2 ml of oil are recovered and the residual oil saturation is re-duced to 29.8%. The additional yie~d from the glycolipid ~ispersion amounts to 22.2 ml or 41% of the residual oil still in the core.
~ m e present invention enables glycolipids to specific structures to be : produced by biological synthesis using aIkane mixtures as the source of carbon and energy, whilst maintainin~ specific parameters and optimizing -the process.
The glycolipid mixtures may tHen be concentrated and either ~etered into the :~ flooding water in the form of aqueous dispersic)n or used directly. FurtHer, as a result of tHe discovery that glycolipid may be separated frc~ the cellular mass by the use of thermal, pH or osmotic shock or by solvent extraction followed by evaporation, glycolipid may be used in econc~ic concentrations as flooding agent.
Still another advantage is that crude oil from the well or oil sands being flood-ed may be used as the source of carbon and energy in the production of the glyco-lipid flood~ng agent.
A further advantage of the method and apparatus of the invention is 2a that the separated cellular mass may be partly recycled, which results in savings, particularl~7 of nutrient salts. Still another advant~ge is that it is possible i to use, for the osmotic-shock process in the second stage, (oil) well water having a salt content of at least 10%.
. The methcd according to the in~7ention makes it possible to use the dispersion containing gl~7colipids during secondary and tert~ary extraction of petroleum from wells or oil sands, by flooding with water, for the purpose of increaslng the yield of petroleum.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

l. A process for the recovery of oil from an oil well or oil sands, which process comprises (1) growing a culture of a micro-organism in an aqueous medium and under aerobic conditions, with the addition of hydrocarbons as an organic source of carbon, inorganic nutrients and air or oxygen-enriched air, at a temperature between 20 and 50°C and at a constant pH value between 3 and 9, the concentration of hydrocarbons in the aqueous medium being from l to 35% by volume, to produce a glycolipid (2) separating the glycolipid from the mass of micro-organism by thermal, pH or osmotic shock or by extraction with a homopolar organic solvent followed by solvent evaporation, and (3) flooding the oil well or oil sands with the separated glycolipid as a flooding agent or as a component in a flooding agent in the recovery of oil from the oil well or oil sands.
2. A process according to claim l wherein the cellular mass which is separated from the aqueous dispersion is wholly or partly recycled to the growing submerged culture.
3. A process according to claim 1 wherein a glycolipid having a struc-ture according fo formula I, wherein m = 8 to 10 and n = 18 to 20:

is produced by the use of a micro-organism of the species nocardia rhodocrous, the hydrocarbon feed being either a mixture of C12 to C19 n-alkanes or crude oil product from the petroleum well or oil sands.
4. A process according to claim 1 wherein a glycolipid having a structure according to the following formula II, wherein m = 20 to 22 and n = 14 to 17:

is produced by the use of the micro-organism mycobacterium phlei, the hydrocarbon feed being either a mixture of C8 to C23 alkanes or crude oil product from petroleum wells or oil sands.
5. A process according to claim 2 or 3, wherein the hydrocarbon feed is a mixture of crude oil and water from the oil well or oil sands, the crude oil constituting between 5 and 35% by volume of the mixture.
6. A process according to claim 1, 3 or 4 wherein the hydro-carbon feed is a crude oil having an n-alkane content of between 5 and 25% by volume and a chain length of between C8 and C24.
7. A process according to claim 1, 3 or 4 wherein the hydro-carbon feed is a mixture of n-alkanes having a chain length of between C8 and C24 and a concentration of between 0.5 and 5% by volume in water.
8. A process according to claim 1 or 2 wherein the glyco-lipid is extracted from the cellular mass with a homopolar organic solvent which is then separated from the glycolipid.
9. A process according to claim 1, 3 or 4 wherein the glyco-lipid is extracted from the cellular mass with a homopolar organic solvent which is then separated from the glycolipid and re-used for the further separation of glycolipid from cellular mass of micro-organism.
10. A process according to claim 3 or 4 wherein glycolipids of formula I or II are produced in two stages, the first stage being carried out at a flow rate of 0.1 to 0.7 Vol/Vol/h, and the second stage at a flow rate of 0.02 to 0.3 Vol/Vol/h.
11. A process according to claim 1, 3 or 4 wherein growth of the micro-organism in the first stage is carried out at a temper-ature of between 25 and 45°C, and in the second stage a thermal shock is carried out at a temperature between 35 and 70°C.
12. A process according to claim 1, 3 or 4 wherein, in the second stage, between 50 and 200% by volume of oil well water or fresh water, having a minimum salt content of 10% by weight, is added in order to produce osmotic shock.
13. A process according to claim 1, 3 or 4 wherein the first stage is operated at a pH value of between 4 and 8, while in the second stage pH shock is carried out at a pH value between 8 and 10.
14. A process according to claim 1 wherein there is fed to the first stage an aqueous nutrient solution which contains ammonium salts, nitrate salts or urea as the source of nitrogen,
15. A process according to claim 14 wherein the aqueous nutrient solution also contains yeast extract or meat extract, re-quired for growth of, and product-formation in, the cellular mass of the micro-organism.
16. A process according to claim 1, 3 or 4 wherein air, or oxygen-enriched air, having an oxygen content of between 20 and 60 by volume, is supplied at an aeration rate of between 0.1 and 2.0 Vol/Vol/min, to the first or second state.
17. A process according to claim 1, 2 or 3 wherein air, or oxygen-enrich-ed air, having an oxygen content of between 20 and 60% by volume, is supplied at an aeration rate of between 0.5 and 1.5 Vol/Vol/min, to the first or second stage.
18. A process according to claim 1, 3 or 4 wherein one or more dispersing agents are added to the aqueous dispersion of glycolipids for stabilization pur-poses.
19. A method according to claim 1, 3 or 4 wherein before being metered into the flooding water, the aqueous dispersion of glycolipids is stabilized by intensive stirring or by ultrasonic treatment.
20. An apparatus for use in preparing a solution of dispersion of glyco-lipid for use in oil extraction comprising in sequence a first vessel which is a first bio-reactor for semi-continuous or continuous aerobic growth of a sub-merged culture of a micro-organism, a second vessel which is a first separator for separating unused carbon-feed source from the culture solution or as a sep-arator to separate cellular mass from a liquid phase of the culture solution, a third vessel which is a second bio-reactor in which a thermal, pH or osmotic shock can be imparted to the culture solution or as an extractor for solvent ex-traction of glycolipid from the cellular mass and a fourth vessel which is a second separator for separating the cellular mass from the liquid phase of the culture solution or as a vaporizer to remove solvent from the glycolipid solu-tion.
21. An apparatus for use in preparing a solution or dispersion of glycolipids for use in oil extraction comprising in sequence a first bio-reactor for the semi-continuous or continuous aerobic growth of a submerged culture of a micro-organism, including means for supply of crude oil from a production drill-hole, means for supply of nutrient salts, means for supply of (oil) well-water, and for air or oxygen-enriched air, means connecting the first bio-reactor to a first separator for separating unused substances from the culture solution, a second bio-reactor connected to the first separator and containing a heat-exchanger and having addition-al supply means for lye, (oil) well water or a salt solution, a second separator, connected to the second bio-reactor, for separat-ing the cellular mass from the liquid phase of the culture solution and a mixer which contains a stirrer mechanism and is provided with discharge means fox the resulting glycolipid solution or dis-persion.
22. The apparatus of claim 20 wherein the first vessel is a first bio-reactor for semi-continuous or continuous aerobic growth of a submerged culture of a micro-organism, the second vessel is a first separator for separating unused carbon-feed source from the culture solution, the third vessel is a second bio-reactor for im-parting a thermal, pH or osmotic shock to the culture solution and the fourth vessel is a second separator for separating the cellular mass from the glycolipid-containing liquid phase of the culture solution.
23. The apparatus of claim 20 wherein the first vessel is a bio-reactor for semi-continuous or continuous aerobic growth of a submerged culture of a micro-organism, the second vessel is a separator for separating cellular masss from a liquid phase of the culture solution, the third vessel is an extractor for solvent extraction of glycolipld from the cellular mass and the fourth vessel is a vaporizer for removing solvent from the glycolipid solution.
24. The apparatus of claim 22 or 23 wherein the fourth vessel is connected to a mixer to produce a glycolipid solution or dis-persion.
25. The apparatus of claim 22 or 23 wherein the first vessel is preceded by a further separator to separate crude oil, for use as carbon-feed source for the culture, from a crude oil-water mixture obtained from a secondary oil recovery.
26. The apparatus of claim 22 wherein the fourth vessel is also connected to the first vessel to permit recycling of separated cellular mass.
27. The apparatus of claim 23 wherein the third vessel is also connected to the first vessel to permit recycling of separated cellular mass.