DE2734364A1 - METHOD OF MANUFACTURING A HYDROPHILIC XANTHOMONIC COLLOID FOR USE IN DISPLACEMENT OR. SHIFTING OF OIL FROM PARTIALLY EXHAUSTED STORAGE - Google Patents

Description

Pfizer Inc.
235 East 42nd Street, New York, NY 1OO17, USA

Process for the preparation of a hydrophilic Xanthomonas colloid for use in the displacement or displacement of oil from partially depleted deposits

The invention relates to a method for producing a a fermentation broth containing Xanthomonas colloid, which are suitable for the production of solutions for mobility control or control of mobility, as they are at used in oil extraction.

There are extensive reports that focus on the production of hydrophilic colloids by aerobic propagation of bacteria of the species Xanthomonas in aqueous nutrient media. The earliest work in this area was in the Northern Regional Research Laboratory of The United States Department

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of Agriculture "in Peoria, Illinois, USA and they are described in US Pat. No. 3,000,790. Modified fermentation processes are in the US patents 3 020 206, 3 391 060, 3 427 226, 3 4-33 708, 3,271,267, 3,251,749, 3,281,329, 3,455,786, 3,565,763, 3,594,280, and 3,391,061.

The hydrophilic colloid (xanthan gum) produced by Xanthomonas campestris is a polysaccharide, which contains mannose, glucose, glucuronic acid, O-acetyl residues and acetal-linked pyruvic acid in a molar ratio of 2: 2: 1: 1: 0.5. This gum or resin and its derivatives have found widespread use in the food field and in engineering. Of special Interest is the increasing focus on the use of xanthan gum in the displacement of oil from partial exhausted supply stores.

Typically, oil is obtained from underground reservoirs by means of a series of sequential operations won. A new well generally delivers a limited amount of oil as a result of the release of the oil internal pressure in the borehole. When this pressure is exhausted it becomes necessary to use more amounts of the oil mechanical equipment to pump. However, these measures only gain about 25% of what is stored in the deposit Total oil. Much of the oil is still trapped within the pores of the formation. Another increase extraction can then be achieved by means of what is known as "secondary extraction". With a method of extraction a water flush by pumping water into a borehole or a series of boreholes, a displacement or moving part of the trapped oil

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the porous rock or the porous formation and that Collecting the displaced oil from the surrounding boreholes carried out. However, a water rinse always leaves high about 55 to 60% of the available oil is trapped in the formation. The explanation for this phenomenon is that water has a very low viscosity in comparison to crude oil and has a tendency to follow the path of least resistance, so that it passes through the oil permeates and leaves large pockets untouched. In addition, surface forces in the formation tend to be that to bind oil and to prevent its displacement or displacement.

A number of operations have been used in recent years to extract additional quantities of oil from these reservoirs Developed through the use of mobility regulating solutions that allow the oil to be displaced through Increases in viscosity or permeability of the displacement fluid increased. Of interest are improved ones Recovery processes that use a polymer rinse apply a polysaccharide or polyacrylamide to increase the viscosity of the displacement fluid. Variations this process include the use of surfactants and co-surfactants for Release of the oil from the rock formation. With polyacrylamides have such disadvantages as a loss of viscosity in saline solutions and a strong sensitivity to it Exposed shear forces. Since, as described in the literature, xanthan gum is insensitive to salts (i.e. does not precipitate or lose viscosity under normal conditions), is stable to shear forces Xanthan gum is heat stable and is stable in viscosity over a wide pH range

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a good means of displacement. In addition, this gum or resin is poor on the elements of the porous Absorbs rock formations and gives advantageous viscosities for improved oil recovery (5 to 90 cP units at a shear rate of 1.32 seconds) at low concentrations (100 to 3000 ppm).

The use of solutions of xanthan gum or derivatives of xanthan gum for oil production is described in US Patents 3,243,000, 3,198,268, 3,532,166, 3,305,016, 3,251,417, 3,319,606, 3,319,715, 3,373,810, 3,434,542 and 3,729,460 described. In US Pat. No. 3,305,016 it is proposed that that aqueous solutions containing the heteropolysaccharide Contained in sufficient quantity to increase viscosity, as a thickener in the manufacture of viscous water flushing solutions can be used. The polysaccharide can be prepared, separated and purified and then added will. Alternatively, according to this reference, the entire culture - after adding a bactericide, e.g. B. from Formaldehyde, to kill the bacteria, to which water for rinsing or flooding is added.

In U.S. Patent 3,000,790, growing a Xanthomonas bacterium in a well ventilated medium containing commercial glucose and an organic source of nitrogen, Contains dipotassium phosphate and suitable trace elements. The most commonly used source of organic Nitrogen are the soluble components from distillation systems. The use of this organic nitrogen source brings a substantial amount of insolubles into the fermentation broth.

Those disclosed in U.S. Patents 3,000,790, 3,391,060, and U.S. Patents 3,000,790; other previously specified fermentation processes described working methods ultimately result in fermentation broths,

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which too substantial amounts of insoluble material, even after dilution with water, for injection into oil-containing or oil-carrying subterranean formations included in order to achieve the required and desired control of the agility for the oil shift. That particulate material and in certain cases the Xanthomonas cells in such a whole broth would be very soon clog the oil-containing or oil-carrying formation at the point of injection and therefore render the borehole unusable make and prevent any further oil extraction. In addition, the same problem would arise with reconstituted resp. reapplied xanthan gum which has precipitated and separated from these fermentation broths occur. The inclination These fermentation broths for clogging can be added by filtration through filters made of diatomaceous earth Removal of the Xanthomonas cells and particulate and colloidal material can be avoided. However, are such additional filter stages are expensive and technically complex and contribute considerably to the overall cost factors for improved oil recovery. In US Pat. No. 3,853,771, the clogging problem of whole fermentation broths is addressed by a process dissolved for the dissolution or dispersion of cell-like microorganisms, this bringing them into contact Materials with an aqueous solution comprising at least one for dispersing the outer wall layers of the microorganism cells effective surfactant, at least one chelating agent for dispersing the internal Wall layers of the microorganism cells and at least one alkali metal hydroxide, which is used to promote these dispersing effects is effective contains.

In the US-Pa tent writing 4- 010 071 is a process for clarification of fermentation broths and other aqueous suspensions which xanthan gum and

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containing suspended solids, described by treatment with a minor amount of a protease enzyme. The injectability of aqueous solutions which contain xanthan gum and have been clarified in this way is at improved oil well flooding operations compared to solutions not treated in this way. However overcomes this treatment does not address the clogging problems as a result of the presence of inorganic or insoluble non-proteinaceous organic materials present in the fermentation medium or during the course of the Fermentation were formed.

The objective of the process of US Pat. No. 3,391,060 is to produce a polysaccharide product of substantial purity without Use of costly cutting operations to gain. Here, a xanthan gum is made from a Xanthomonas fermentation broth of high quality, high viscosity, light color and high purity. According to this Patent specification simplifies the extraction and cumbersome cleaning procedures are avoided by the organic Source of nitrogen in the fermentation broth by an inorganic source of nitrogen, e.g. B. ammonium nitrate, is replaced. However, the fermentation process described here is because of the long reaction times required and the low yields of biopolymer obtained are not economical.

US Pat. No. 2,867,279 discloses a method of improving the permeability of mobility control solutions by adding certain hydroxy substituted ones Carboxylic acids such as malic acid, tartaric acid, citric acid, Gluconic acid, lactic acid and salicylic acid are described.

The object of the invention is an economical and technically simple process for the production of a Xanthomonas colloid

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containing fermentation broth, which is suitable for the production of solutions used in oil extraction for mobility control.

The method according to the invention serves to solve this problem, which comprises the aerobic fermentation of a Xanthomonas organism in an aqueous nutrient medium, its Ingredients a carbohydrate, a nitrogen source, an acid for the Krebs cycle, chelated calcium, manganese ions

/( i.e. trace elements) and iron ions / include. The total broth formed provides the solutions for mobility control with about 100 to 3000 ppm Xanthomonas colloid, being free of insoluble material with a particle size greater than about 3 microns are.

The invention is explained in more detail below.

According to the invention it is possible for the first time to produce a Xanthomonas fermentation broth in a practical process, those without treatment or clarification mobility control solutions for use in oil production with a Use concentration of about 100 to 3000 ppm Xanthomonas colloid supplies, these solutions being essentially free are of insoluble material with a particle size greater than about 3 microns. According to the invention, the entire Fermentation broth can be used directly as a motility control solution as such, if the amount of colloid formed during fermentation is within the desired application concentration range. Alternatively, the broth can be diluted with water or a water solution such as saline can be used to degrade the content of colloid added to the desired range

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will. Additives for modifying the properties of the solutions for mobility control can additionally can be used in the whole broths and uncleared broths of the invention, respectively.

It has been found that oil in kernels from oil fields in general can be effectively obtained by xanthan gum if it is achieved that the polysaccharide solution a "Millipore filter test" at the application concentration, as described below. Typical pore sizes of millipore filters that are used for this Test used are 0.45 to 3 »0 microns.

In addition to filterability through Millipores, tests are carried out on cores as described by W. B. Gogarty in Mobility Control with Polymer Solutions, Paper (SPE 1566B) presented at the 41st Annual Fall Meeting of Society of Engineers in Dallas, Texas, USA from April 2-5 10. 1966.

A new feature of the fermentation broths according to the invention, which makes them significantly different from the previous ones The difference between the described Xanthomonas fermentation broths and preparations is the lack of a need for expensive ones and time consuming filtration and clarification. Key factors in making this possible are the following:

1. All nutrient ingredients are essentially water soluble or become essentially during the course soluble in water after fermentation or before injection;

2. An absolute asepsis becomes during the course of the fermentation maintained, and preferably a bactericide at the end of the. Added fermentation;

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3. hard water with high concentrations of calcium ions • is preferably not used to prepare the fermentation media. Low levels of calcium ions (less than about 100 mg / 1, preferably less than about 60 mg / 1) can by adding an ohelating agent how to be sequestered or intercepted by ethylenediaminetetraacetic acid or preferably citric acid;

4. Levels of manganese ions can be controlled to prevent seed crystal formation and insoluble precipitation Avoid calcium and phosphate salts (about 0.75 to 60 ppm, preferably 1.5 to 24 ppm;

5. The amounts of trace iron are controlled so that

the formation of seed crystals and the precipitation of insoluble calcium phosphate salts is avoided.

The addition of the following ingredients to promote rapid cell growth is essential for the method according to the invention and to increase the xanthan yield during the preparation of the desired mobility control solutions, which contain essentially no insoluble material having a particle size above about 3 »0 microns:

1. Chelated calcium - about 1 to 200 ppm, preferably about 40 to 60 ppm;

2. Trace iron - about 0.25 to 20 ppm, preferably 0.5 to 8 ppm;

3. Acid for the Krebs cycle - about 0.1 to 10 g / l, preferably about 1 g / l.

The trace amounts of manganese and iron (II) ions are added in the form of salts such as MnSO ₄ .H ₃ O, MnCl ₂ , FeSO ₄ .7H ₃ O and.

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The acid for the Krebs cycle is an assimilable acid, which is derived from citric acid, oxaloacetic acid, 1-malic acid, fumaric acid, succinic acid and oxalosuccinic acid is selected from the existing group. cis-aconitic acid is a Krebs cycle acid which is not useful in the method of the invention. The preferred acid is citric acid because of its additional effectiveness as a sequestering agent for calcium ions. Citric acid can be added to the fermentation medium at a concentration of about 0.5 to 2 g / l, preferably about 1 g / l will.

In carrying out the invention, a suitable fermentation medium is inoculated with an organism of the species Xanthomonas. The inoculation medium can be YM broth (Difco) or a medium containing raw glucose (Cerelose), sodium and potassium phosphates, magnesium sulfate, and any of a variety of organic sources of nitrogen such as an enzymatic breakdown product of soybeans (Soy Peptone Type T, Humko-Sheffield Chemical Co.) or an enzymatic breakdown product of casein (NZ-Amine YT, Humko-Sheffield Chemical Co.). After the aerobic propagation for about 30 hours at 28 ^° C., a portion is transferred to a fermentation device for inoculation in the second stage.

A suitable carbohydrate is present in the nutrient medium at a concentration of from about 1 to about 5 percent by weight. Suitable Carbohydrates include e.g. E.g .: glucose, sucrose, maltose, fructose, lactose, processed, inverted beet molasses, Invert sugar, filtered, diluted high quality starch hydrolysates or mixtures of these carbohydrates. The preferred Carbohydrates are glucose, maltose, fructose, filtered starch hydrolysates or mixtures thereof.

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Inorganic nitrogen is present in the nutrient medium at a concentration of from about 0.02 to about 0.35% by weight and is preferred from 0.07 to 0.25 weight percent. Inorganic nitrate is the preferred source of nitrogen; Ammonium nitrate in an amount of about 1 g / l, sodium nitrate in an amount of about 2 g / l or potassium nitrate in an amount of about 2.4 g / l can be used. The preferred source of nitrogen in this medium as well as in the production medium is inorganic in nature. However, organic nitrogen sources can also be used despite the formation of large Xanthomonaε cells, provided that the main requirement of the practical freedom from insoluble materials with a particle size above about 3 microns is maintained.

Magnesium in the form of MgSO ^ .7HpO or Epsom salts, 0.1 to 1.0 g / l, is added along with trace amounts of manganese and iron ions. A chelating agent such as ethylenediaminetetraacetic acid or preferably citric acid, which also acts as a growth-promoting acid in the Krebs cycle, and sequestering agents for any calcium present are added.

Sufficient amounts of mono- and dipotassium phosphates are added to buffer the medium to about pH = 5-9 to 8.5 and preferably 6.0 to 7-5. After the aerobic propagation for about 20 to 40 hours at 24 to 34 ^° C. and preferably 28 to 30 ^° C., a portion is transferred to a fermentation device which contains the production medium.

The composition of the production medium is that of the medium for vaccination in the second stage similar except that sodium phosphates are preferred over potassium phosphates because of their lower cost

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can be used and that a small amount of calcium in the form of a salt such as calcium chloride or calcium nitrate or oxide, e.g. B. lime, is added to increase the xanthan yield. The amount of calcium added depends on the amount of calcium that is needed in the preparation of the medium the water used, the nitrogen source used, and the type and strain of Xanthomonas organism used away. When using sodium nitrate or potassium nitrate instead of ammonium nitrate there is less calcium required (approximately 27 ppm). Deionized water, distilled water, or less than about 20 ppm calcium or other water containing cations which can be precipitated by phosphate can also be used to make up the medium will. Calcium ions can be added in a desired concentration. The role of calcium ions in promoting While xanthan gum production is essential, the process of the present invention involves preventing precipitation of excess calcium ions and other cations as insoluble phosphate salts are critical. This will, if desired, by adding a chelating agent such as ethylenediaminetetraacetic acid or another suitable compound known per se in the art at a concentration from about 1 to 20 millimolar, and preferably from 2 to 8 millimolar.

The pH of the fermentation medium is very important for suitable growth of the Xanthomonas bacteria. Of the preferred range is about 6.0 to 7 »5 · the control the pH within this range can be adjusted through the use of a buffer compound such as disodium acid phosphate can be achieved. Ethylenediaminetetraacetic acid or other suitable chelating agent is also used in the buffer solution used for pH adjustment

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is added to the precipitation of calcium ions, which introduced into the water used to prepare the medium were considered to prevent insoluble calcium salts. The pH is preferably adjusted during the fermentation cycle controlled by addition of sodium or potassium hydroxide solution, this having the additional benefits of reducing the Broth viscosity without affecting the xanthan yield and eliminating the need to chelate the Has buffer solution.

To achieve rapid fermentation, it is essential to have the right amount of oxygen for the growing bacterial culture available. The fermentation medium is aerated to deliver sufficient oxygen to a Sulfite oxidation value increases within the range of about 1.5 to about 3-5 millimoles of oxygen per liter per minute obtain. A description of the determination of the sulfite oxidation value is given in Industrial Engineering Chemistry J56 (1936), P. 504 given. The sulfite oxidation value is a measure of the rate of oxygen uptake in the fermentation device under the conditions of agitation and the Ventilation.

The fermentation is allowed to proceed at a temperature of about 30 ^° C. until the broth has a xanthan concentration of at least about 100 ppm and preferably at least about 1.0% and particularly preferably at least about 1.4 % , ie 30 to 96 hours . The broth viscosities are typically at least about 4,000 cP units, and preferably about 7,000 cP units.

It is desirable to protect the microorganism cells by adding a bactericide such as formaldehyde, glutaraldehyde, phenol or a substituted phenol such as cresol or

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Hydroxybenzene or a polyhalogenated phenol such as from Corexit (Exxon Corporation) or any other preservative known in the art kill. The preferred bactericide or preservative is formaldehyde at one concentration from about 200 to 10,000 ppm, preferably from about 1000 to 3000 ppm, being added to the finished fermentation broth or can be added during storage.

The method of the invention works well on many of the different types of Xanthomonas bacteria. Typical examples of species include: Xanthomonas phaseoli, Xanthomonas malvacearum, Xanthomonas carotae, Xanthomonas begoniae, Xanthomonas incanae and Xanthomonas vesicatoria. The preferred species is Xanthomonas campestris.

The Millipore Filterability Test is an experimental test that measures the flow rate through a Millipore filter (0.45 to 3.0 µm pore size) as a function of a volume under a constant pressure of 2.81 atmospheres. The filter ratio is the ratio of the time to the Collect the fourth 250 ml of the mobility control solution at the time to collect the first 250 ml of the solution Mobility control. A filter ratio of 1.0 indicates that the solution shows no tendency to clog. An acceptable one Mobility control solution has a filter ratio of 1 to 3 (0.45 to 3 / i millipore filter), preferably <1.7

The desired filter ratio and millipore filter size for testing a specific mobility control solution depend on the permeability or permeability of the subterranean layer of the oil field at which such oil displacement is planned from.

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The mobility control solutions prepared from the total fermentation broths according to the invention have filter ratios which are suitable for use on most oil fields. Where underground layers are highly impermeable, mobility control solutions with lower filter ratios must be used. In such circumstances, the whole broths of the present invention, or unclarified broths, preferably contain virtually no insoluble material having a particle size above about 0.65 μm. This can be achieved simply by storing the finished fermentation broth in the presence of about 200 to 10,000 ppm formaldehyde for a period of about 3 to 4 days. This aging process causes the Xanthomonas cells to shrink so that their smallest dimensions are 0.65 μm. not exceed. Xanthomonas cells are rod-shaped and typically the longer dimension of the cells is greater than 0.65 µm while the smaller dimension of the cells is about 0.4 to 1.0 µm. The storage temperature is not critical and can range from 0 ^° C. to 135 ^° C. and preferably from 20 ^° C. to 45 ^° C. A practical expedient is to store at room temperature for a sufficient period of time that microscopic examination shows that the smaller dimension of the Xanthomonas cells is no greater than 0.65 µm (3 to 4 days).

The following values show the influence of the ingredients of the medium on the filter ratios of the solutions for Mobility controls made from aged fermentation broths:

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I. ) FeSO ₄ .7H ₂ O
(mg / 1) CaCl ₂ .2H ₂ O
(K / l) Lemons
acid
(k / 1) % Xanthan gum Filter ⁺⁺ I. N O Tabel Nitrogen source content of ingredients ⁺ 10 0.1 1.0 relationship
(0.8 µm
Pore size) MnSO .. 7H _O (
4 C.
(mg / 1) 10 0.1 1.0 1.76 1.29 NaNO, (2 g / l) 31
^5-15 5 0.1 1.0 1.90 1.53 31 10 0.1 0.0 1.86 31 10 0.2 1.0 1.79 > 3 * 31 10 0.0 1.0 1.79 > 3 31 10 0.2 1.0 0.90 2.22 NH ₄ NO, (1 g / l) 51 10 0.2 1.0 1, * 7 ⁴ * 15 5 0.2 1.0 V, 96 1.93 31 10 0.2 0.0 1.90 1.84 31 10 0.3 1.0 1.57 \ 5 31 10 0.0 1.0 2.08 > 3 31 10 0.1 1.0 1.17 2.09 KNO, (2.4 g / L) 51
⁵ 15 10 0.1 1.0 1.72 1.54 31 5 0.1 1.0 1.77 1.72 31 10 0.1 0.0 1.80 1.33 31 10 0.2 1.0 1.27 1.54 31 10 0.0 1.0 1.93 > 3 0.81 > 3

+ All media were made up with distilled water and, in addition to the stated ingredients, contained D-glucose «27 g / l; D-fructose ■ 3 g / l; NaH ₂ PO _{4 .H 2} 0 >> 0.70 g / 1; Na ₂ HPO ₄ = 3.3 * g / l + 2.445 g / l, added after 17 h

++ All broths diluted to about 750 ppm xanthan gum.

to

co -P-CO CJ)

Table II

Nitrogen source

Ingredients of the medium

% Xanthan gum

Filter ratio

Fernamine IV

Liquid fractions from distillate equipment (Distillers' Solubles)

enzymatic breakdown product of casein, 2 g / l (NZ Amine YT)

enzymatic breakdown product of soybeans, 2 g / l (NZ Soy)

U.S. Patent 3,391,060

US-FS 3,000,790

Example II Example II

0.8

0.99 0.89

> 3 (0.80 µm)> 3 (0)

> 3

> 3

As an alternative to the aging process, an alkali metal hydroxide such as sodium or potassium hydroxide can be added to the finished fermentation broth in a concentration of 0.1 to 2.0% w / v and preferably 0.5% w / v together with an alkali metal salt such as sodium or potassium chloride or sulfate in a concentration of 0 to 5 w / v. -% and preferably 1.0 w / v. -% are added. The preferred salt is sodium chloride. The broth is heated ^{to a temperature of 55 to 121 °} C. and preferably 85 to 95 ^° C. under an oxygen-free atmosphere (e.g. nitrogen). The heating time is not critical and can be extended to several hours. A practical length of time is 1 to 30 minutes, and preferably about 10 minutes. The broth is cooled to room temperature and adjusted to pH 3 to 12 and preferably 7 with an acid such as hydrochloric acid. This alkaline heat treatment hydrolyzes the bacterial cells without affecting the xanthan gum content. Deacetylation of the xanthan occurs during this process and the deacetylated product is very suitable for use in oil production.

The suitably aged or alkaline heat-treated fermentation broth is generally mixed with water or saline to a xanthan gum concentration of about 400 to 1000 ppm diluted for use in improved oil recovery. Optionally, a surfactant can be used to increase be added to the oil production. Typical surfactants include the various Petroleum sulfonates known to those skilled in the art of oil production are known per se.

It should be noted that there may be conditions and factors conducive to the transport of large volumes

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Make fermentation broths impractical or costly for injection into oil-bearing reservoirs. For such purposes it will supplied a special composition. To the previously described, alkaline-heat-treated broth is added Sufficient water-miscible solvents such as methanol, ethanol, acetone, t-butyl alcohol or isopropanol Amount added to precipitate the xanthan gum, which is separated by centrifugation or filtration and dried will. The preferred water-miscible solvent is isopropanol at a concentration of 20 to 75 w / w% and preferably about 38% w / w. The reattachment or reconstitution with water or saline to a xanthan gum concentration of 100 to 3000 ppm provides a Composition for improved oil recovery in terms of performance with a diluted total fermentation broth is comparable. During the process of re-dissolution it is essential to have sufficient Provide shear to provide adequate dispersion of the polysaccharide and the formation of lumps to prevent.

The test procedures are explained in more detail below:

Millipore filterability test

1000 ml of a 750 ppm xanthan gum solution in 500 ppm salt solution (10: 1 - NaCl: CaCl ₂ ) were prepared as follows: In a mixer of the Waring type, which was equipped with a variable resistor, sufficient broth (based on the xanthan gum Content) entered to provide 0.75 6 xanthan gum solids. It was diluted to 1: 6 with saline. This mixture was sheared as follows:

40 % performance / 2 minutes 60% performance / 2 minutes 80% performance / 2 minutes.

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Xanthan was diluted to 750 ppm in the mixer and sheared at 40 % power for 2 minutes. This solution was also used to determine the viscosity.

An experimental set-up was used which comprises measurements of the flow rate through a disk of a millipore filter (47 mm, 0.45-3 »O µm pore size) as a function of the Volume under a constant pressure of 2.81 atm. A storage container was used that was more than 1000 ml could grasp.

The storage container was filled with 1 l of the xanthan gum solution (750 ppm) filled. The pressure was adjusted to 2.81 atmospheres. The valve was opened and it started recording the volume of filtrate and the time (seconds) started.

Filter ratio =

Time to collect the fourth 250 ml of the

Solution

Time to collect the first 250 ml of the solution

Determination of viscosity

The viscosity was measured with a synchro-electric Brookfield viscometer, Model LVT measured using a UL adapter. The measurement was carried out at 25 ° C. and 6 and 12 rpm.

The viscosity was measured in centipoise units (cP units)

specified.

Determination on xanthan

Highly purified xanthan gum contains about 18.4 % glucuronic acid. Glucuronic acid in xanthan compositions is in the absence of formaldehyde and without borate at 100 ⁰ C after

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Method of Knutson and Jeanes, Anal. Biochem., 24 (1968), P. 470 and 482.

% Xanthan = ^% & lucoronic acid χ 100

The invention is illustrated in more detail by means of the following examples.

example 1

Cells of Xanthomonas campestris from a YM agar slant culture were transferred to 300 ml of a YM broth, which were contained in a 2.8-1 Fernbach bottle, and shaken ^{at 28 ° C. on a rotary shaker for about 31 hours.} A portion of 25 ml was transferred to a 2.8-1 Fernbach bottle containing 500 ml of a mesium with the following composition:

Component g / 1

separately 10.1. in the autoclave

Glucose-Fructose (Isosweet 100, Com Products)

raw glucose (cerelose) SehanSelt ²⁵ > ⁷

NH ₄ NO ₃ * 1.0

MgSO ₄ .7H ₂ O 0.10

MnSO ₄ .H ₂ O 0.03

FeSO ₄ .TH ₂ O 0.01

anhydrous citric acid 1.0

K ₂ HPO ₄ 4.1

KH ₂ PO ₄ 0.69

The raw glucose (Cerelose) and the glucose-fructose (Isosweet) were dissolved in distilled water and placed in an autoclave treated. The rest of the ingredients were combined, adjusted to pH 6.4 and autoclaved. the

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Separately autoclaved materials were then combined.

After shaking at 28 ^° C. for about 33 hours, a portion of 200 ml was transferred to a mechanically stirred 4-liter fermenter which contained 2 liters of the following medium:

component

raw glucose (cerelose) glucose-fructose (Isosweet 100,

separately 25.7. in the car

10.1

Com Products) J {£ j} _elt

0.10

J NH ₄ NO ₃ 1.0

₄₂

MnSO ₄ .H ₂ O 0.03

FeSO ₄ .7H ₂ O 0.01

anhydrous citric acid 1.0

CaCl ₂ .2H ₂ O 0.20

Na ₂ HPO ₄ 3.34-

NaH ₂ PO ₄ 0.70

The sugars dissolved in 300 ml of water were autoclaved separately. The remainder of the ingredients, dissolved in 1700 ml of water, were autoclaved and the two solutions were then combined. The ventilation was carried out at such a rate that 1.5 to 3-5 millimoles of oxygen per liter per minute were delivered. The fermentation was carried out at 30 ^° C. for 48 hours, the pH of the medium being kept between 5.9 and 7.5 during this period by adding sodium phosphate buffer which had been made up with tap water. Furthermore, ethylenediaminetetraacetic acid was added to the sodium phosphate buffer to prevent the precipitation of calcium phosphate salts. At the end of the fermentation it amounted to

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the viscosity of the broth> 7800 cP units (at 6.27 ^{seconds "1} shear rate) and the xanthan yield was> 1.5%.

One mobility control solution had a filter ratio of <1.7 (3.0 µm millipore filter).

One from the total fermentation broth aged for 4 days The solution prepared for mobility control had a filter ratio of «1.7 (0.65yum millipore filter).

Example 2

The procedure of Example 1 was repeated, except that the

the following fermentation media were used:

Components p / 1

raw glucose (cerelose) pH - 7.0 10.0 (NH ₄ ^ PO ₄ 2.0 KH ₂ PO ₄ 1.0 MgSO ₄ .7H ₂ O ^ separated 0.5 enzymatically degraded casein lim car
slave (NZ-Amine YT) ) treated 11.0 Imj> fmedium (2nd stage) Components K / l D-glucose 27.0 D-fructose 3.0 NH ₄ NO ₅ 1.0 MgSO ₄ .7H ₂ O pH - 6.4 0.10 MnSO ₄ .H ₂ O 0.03 FeSO ... 7H _o 0 0.01 anhydrous citric acid 1.0 K ₂ HPO ₄ 4.1 KH ₂ PO ₄ 0.69

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Production medium

Components I separated im
? Autoclaves
J treated 27.0
3.0 D-glucose
F-glucose 1.0 anhydrous citric acid 1.0 NH ₄ NO ₃ 0.10 MgSO ₄ .7H ₂ O 0.03 MnS O ₄ . H ₂ O 0.01 FeSO .. .7H ₀ O 0.20 CaCl ₂ .2H ₂ O pH - 6.4 3.34
0.70 Na ₂ HPO ₄
NaH ₂ PO ₄

The fermentation was carried out according to Example 1 with comparable results, but with the exception that the pH was adjusted with sodium hydroxide solution without the simultaneous addition of ethylenediaminetetraacetic acid.

Example 3

Large scale fermentation was carried out in the following manner

carried out:

Components r / 1

raw glucose (cerelose) 10.0

(NH ₄ ) ^ PO ₄ 2.0

KH ₂ PO ₄ 1.0

MgSO ₄ .7H ₂ O 0.5

enzymatically degraded casein pH - 7.0 11.0 (NZ-Amine YT)

The medium was in 500 ml portions in two 2.8-1 Fernbach bottles entered. After the treatment in the autoclave (sterilization) and cooling, the bottles were filled with cells

709886/0792

as

inoculated by Xanthomonas campestris. After shaking for 30 hours at 28 ^° C., the two bottles were combined and used to inoculate a fermentation device of 757 l, which contained the following components in 379 l of medium:

ImDfmedium_ (2 _r _stufe)

Components Quantity (kg)

raw glucose (cerelose) 4.54

0.907

₂₄ 0.454

Epsom salt 0.227

enzymatically degraded casein 4.99

(NZ-Amine YT)

pH - 7.0

The fermentation medium was fed with a mechanical guide stirred and aerated so that 1.5 to 3.5 millimoles of oxygen were delivered per liter per minute. Sodium hydroxide solution was added at intervals to bring the pH up 6.0 to 7.5 hold. It became soy for control excessive foaming added. After about 48 hours of fermentation, the volume needed to deliver a 5 v / v% inoculum was sufficient, transferred to a fermentation device 7570 1, the 3028 1 medium with the following Composition included:

£ 3 _S tuf ^e )

Ingredients quantity

NH ₄ NO ₅ (50% solution) K ₂ HPO ₄ KH ₂ PO ₄ Epsom salt

MnSO ₄ .H ₂ O

709886/0792

5.0 1 12.5 kg 21.5 kg 306 β 94

- 26 -

Components

PeSO ₄ .7H ₂ O

raw glucose (cerelose)

Glucose-Fructose (Isosweet 100)

anhydrous citric acid

lot

30th , 5 G Ί separated 79 kg Lim auto Slave
) treated 31 ,8th kg 3, 06 kg pH - 7.0

After fermentation under the conditions described above For about 31 hours, a sufficient volume to deliver a 10% v / v inoculum was transferred to a fermentation device of 7570 1, which 4540 1 of the following Medium contained:

Production medium

Components

raw glucose (cerelose)

Glucose-Fructose (Isosweet 100)

NH ₄ NO ₅ (50% solution) slaked lime (Ca (OH) ₂ ) anhydrous citric acid amount

Na ₂ HPO ₄
NaH ₂ PO ₄
Epsom salt
MnSO ₄ .H ₂ O
FeSO ... 7H ₀ O

(MgSO,

separated
►in the car
slave
treated 134.6
53 kg
kg 7.57 1 0.33 kg 4.54 kg 15.2 kg 3.18 kg 0.454 kg 0.141 kg 0.0454 kg pH - 7.0

709886/0792

Claims (14)

Claims 1. Method of making a Xanthomonas colloid containing fermentation broth, which are used for the preparation of solutions for mobility control, as used in the oil extraction are used, is characterized in that a Xanthomonas organism in an aqueous nutrient medium, its constituents Carbohydrate, a source of nitrogen, about 0.1 to 10 g / l Acid assimilable in the Krebs cycle, approx. 1 to 200 ppm chelated calcium, approx. 0.25 to 20 ppm iron and trace elements are as long as aerobically fermenting is carried out until at least about 100 ppm colloid is present in the broth, whereby the total broth formed. Solutions for mobility control with about 100 to 3000 ppm Xanthomonas colloid content which is virtually free of insoluble material having a particle size greater than about 3 microns are. 2. The method according to claim 1, characterized in that a chelating agent during fermentation in a Amount of about 2 to 20 millimolar is added, and that the chelating agent is ethylenediaminetetraacetic acid is. 3. The method according to claim 1, characterized in that the acid for the Krebs cycle is citric acid, and that the concentration of citric acid in the nutrient medium is about 0.5 to 2 g / l. 4. The method according to claim 1, characterized in that a preservative is added to the broth after fermentation is added in an amount of about 200 to 10,000 ppm and that the preservative is formaldehyde. 709886/0792 OWGiNAL INSPECTED 5 · Procedure according to. Claim 1, characterized in that the nitrogen source ammonium nitrate, or sodium nitrate Is potassium nitrate. 6. The method according to claim 1, characterized in that the aqueous nutrient medium is prepared using water which contains less than 20 ppm calcium and other phosphate precipitable cations. 7 · Method of making a Xanthomonas colloid containing fermentation broth, which is used in the production of solutions for mobility used in oil extraction control is suitable, characterized in that a) a Xanthomonas organism in an aqueous nutrient medium, Its components are a carbohydrate, a nitrogen source, about 0.1 to 10 g / l of one in the Krebs cycle assimilable acid, about 1 to 200 ppm chelated calcium, about 0.25 to 20 ppm iron and trace elements include as long as fermentation is carried out until there is at least 100 ppm colloid in the broth, and b) the broth is stored for 3 to 4 days, creating a a hydrophilic colloid-containing fermentation broth is obtained which is substantially free of insoluble Is material whose particle size is greater than 0.65 μπα. 8. A fermentation broth containing a hydrophilic colloid, prepared by the method according to claim 7 9. Use of the fermentation broth according to claim 8 in the production of crude oil from an oil-containing or oil-bearing, underground formation. 10. Process for the extraction of crude oil from an oil containing or oil-bearing, subterranean formation, with a solution containing a hydrophilic colloid for mobility control injected into the formation, thereby 709886/0792 characterized in that a solution for mobility control is injected into the formation, which one after the fermentation broth obtained by the method according to claim 1. 11. Process for the production of crude oil from an oil containing or oil leading underground formation, wherein a solution containing a hydrophilic colloid for Mobility control is injected into the formation, characterized in that a solution is injected into the formation is injected for mobility control, which contains a fermentation broth obtained by the method according to claim 7. 12. A process for the preparation of a fermentation broth containing a hydrophilic colloid, which is used in the extraction of oil from an oil-bearing underground Formation by injecting a mobility control solution containing this broth into the formation is suitable, characterized in that a) a Xanthomonas organism with aerobic propagation in an aqueous nutrient medium, the components of which are a carbohydrate, a nitrogen source, about 0.1 to 10 g per liter of an acid for the Krebs cycle, about 1 to 200 ppm chelated calcium, about 0.25 to 20 ppm iron and trace elements comprise, as long as fermentation is carried out, until at least 100 ppm colloid in of the broth, and b) the broth with an alkali metal hydroxide in a concentration of 0.1 to 2.0 w / v. -% and an alkali metal salt in a concentration of 0 to 5 w / v% is brought into contact, is heated for 1 to 30 minutes to about 55 ⁰ C to 121 ⁰ C under a substantially oxygen-free atmosphere and optionally is neutralized. 709886/0792 13 A fermentation broth containing a hydrophilic colloid, produced by the method of claim 12. 14. Process for the production of a hydrophilic colloid, that for use in the extraction of oil from an oil-bearing subterranean formation by injection a solution containing this hydrophilic colloid is suitable for controlling mobility in this formation, characterized in that a) with aerobic propagation, a Xanthomonas organism in an aqueous nutrient medium, its constituents Carbohydrate, a source of nitrogen, about 0.1 to 10 g / l an acid for the Krebs cycle, about 1 to 200 ppm chelated calcium, about 0.25 to 20 ppm iron and Include trace elements as long as fermentation takes place until there is at least 100 ppm colloid in the broth, and b) the broth is contacted with an alkali metal hydroxide in a concentration of 0.1 to 2.0 w / v% and an alkali metal salt in a concentration of 0 to 5 w / v% for 1 to 30 years minutes heated to about 55 ° C to 121 ⁰ C under a substantially oxygen-free atmosphere and is optionally neutralized, and c) sufficient water-miscible solvent is added to cause precipitation of the hydrophilic colloid and that the precipitated hydrophilic colloid is separated therefrom. 15 · mass in the form of a hydrophilic colloid, obtained after Method according to claim 14. 709886/0792