DD229136A1 - METHOD FOR THE TREATMENT AND DESALINATION OF PETROLEUM - Google Patents

Abstract

The invention relates to a process for the chemical dewatering and desalination of Erdoelen with demulsifiers based on oligomeric a-methylstyriol. The object of the invention is to find suitable demulsifiers for the desorption and desalination of Erdoelen and high Effektivitaet, which greatly reduce the water and salt content of the oil and reach a high speed of Entwaesserung and desalination. This is achieved by using oligomeric α-methylstyrene diol or polyglycol ether of the oligomeric α-methylstyrene diols as demulsifiers.

Description

Title of the invention

Process for drainage and desalination of crude oil

Field of application of the invention

The invention relates to a process for dewatering and desalting petroleum with the aid of nonionic surfactants.

Characteristic of the known technical solutions

In the extraction of oil from underground deposits petroleum emulsions are predominantly brought to light. Petroleum emulsions are intimate mixtures of immiscible liquids such as petroleum and water. The water is distributed in the finest droplets in Eohöl and the emulsion by the also contained therein "natural" emulsifiers which accumulate in the interface, so stabilized that the two phases can not be separated by a simple settling process in an economically acceptable manner. «2 -

For splitting of such emulsions, use is made in the art in addition to simple heating to about 80 ⁰ O and skidding or applying electrical stress fields in recent times, surface-active compounds, so-called splitters, which are added to the stationary or flowing the emulsion in small amounts.

Among the variety of substances already proposed for this purpose, the following compound types have found their way into practice, among others. Alkyl sulfates and alkylaryl sulfonates and petroleum sulfonates in the form of amine salts. Furthermore, addition products of the Bthylenoxids were to suitable compounds with active hydrogen, such as. B. Alkylphenols, eicinus oil, fatty acids, fatty alcohol and aldehyde resins (N, Schonfeldt, surface active addition products of the Ithylenoxids, Wiss. Verlagsges MBH Stuttgart 1959 p 275), block polymers of propylene oxide and ethylene oxide, as obtained by addition of ethylene oxide to polypropylene glycols ( US Pat. No. 2,674,619 and DE-AS 1 018 179).

The aforementioned splitters have more or less severe defects and meet the desired requirements only partially. Either the total separation is poor and the Salzaustrag moderate in spontaneous initial cleavage or the splitting process is indeed slow in good salt and water separation. Sometimes their use is specifically bound to a few oils.

Object of the invention

The object of the invention is to effectively improve the cleavage of petroleum emulsions by new demulsifiers or to provide demulsifiers which are suitable for splitting the most diverse types of petroleum with high efficiency, d. H. the water and salt content

of crude oil and cause dehydration and desalination at high speed.

Explanation of the essence of the invention

- The technical problem of the invention

The invention has for its object to develop a process for dewatering and desalination of petroleum by the use of nonionic surfactants according to the object of the invention.

Features of the invention

The object is achieved in that oligomeric <* - methylstyrene or polyglycol ethers of the oligomeric <* -methylstyrenediol of the following formula as demulsifiers

CHO

- - CH-CH ₂ - - CH-CH ₂ -O- [C ₂ H ₄ Oj -H

be used, wherein a: O to 15 ethylene oxide units and b: O to 6, preferably 2 to 4 oC. Mean methylstyrene units and the oC methylstyrene having a functionality between 1 and 2, preferably between 1.5 and 2.

It has surprisingly been found that oligomeric o-methylstyroldiol or oxyalkylated oligomeric styrene diols exceed such demulsifiers in their effectiveness, which have hitherto been used in practice with good results, such as Dissolvan 44-11 or the demulsifier R 11.

-Main the advantage of oxyalkylated oligomers oi -Methylstyroldiolen consists in the rapid separation of petroleum emulsions in oil and aqueous phase, the increased degree of cleavage and low salt content of the Bestwassersowie demulsified oil compared to treatment with the known demulsifiers.

The proposed demulsifiers are prepared by the addition of ethylene oxide to oligomeric red methyl styrene diol obtained via anionic polymerization of <* -methylstyrene followed by hydrolysis of the alcoholate.

It is surprising that such compounds, which have significantly lower molecular weights compared to the conventional block copolymers of polypropylene glycol and polyethylene glycol units, show better effectiveness. Obviously, the lower molecular weight and the fact that the hydrophobic and hydrophilic groups in the molecule are very severe, the surprising reason why the compounds diffuse very quickly to the interface and therefore can develop their full effectiveness very quickly in that even oligomeric α-methylstyrene diol which is not reacted with ethylene oxide also possesses the interface-active properties necessary for good effectiveness as demulsifier for drainage and desalting of petroleum.

However, the addition of ethylene oxide further improves the efficiency of drainage and desalination of petroleum. Even beyond the proposed range of oxyethylation, these compounds still have the ability to be effective in the dewatering and desalting of petroleum, but this effectiveness weakens with increasing degree of oxyethylation.

A further advantage of the invention is that the demulsifiers according to the invention can be applied to a wide variety of crude oil types, as is the case, for example, for Devonian and Carbonic petroleum oils.

The proposed demulsifiers are predominantly 81-soluble compounds, which have the advantage that they do not entail environmental problems due to the wastewater load. Their presence in petroleum does not adversely affect further processing. On the contrary, in subsequent Auswaschprozessen during further processing, their effectiveness is still useful.

The invention will be explained in more detail in the following embodiments.

embodiments Example 1:

The demulsifying ability of the proposed reagents was determined on re-emulsified petroleum emulsions with petroleum from the deposit Reinkenhagen (GDR). 70.7 g of the petroleum (water content less than 0.5 %) were heated with stirring in a 150 ml beaker in a thermostat at 60 ⁰ C. Then, 20 ml of warmed distilled water was added at 60 ⁰ O and mixed for 5 minutes with the oil. 4.5 minutes after the addition of water, the demulsifier is added as a 2% solution in toluene. After stirring, 50 ml of petroleum emulsion are placed in a measuring cylinder heated to 60 ⁰ O in a water bath, this sealed with a stopper and left for 2 hours at 60 ⁰ C in a water bath. The amount of water removed in the graduated cylinder is determined after 2 hours and calculated as a percentage of the total amount of water added.

  - 6 -

The following demulsifiers were used as 2% solutions in toluene in concentrations of 20, 40, 100 and 200 ppm (calculated on 100 % active substance) and tested s

1. polyglycol ethers of the oligomeric <& -Methylstyroldiols (Compound S 1), prepared from 1 mole of oligomeric oO-Methylstyroldiol and 15.7 Mpl ethylene oxide with following physical-chemical characteristic data: hydroxyl value (mg KOH / g) 73 1310 molecular weight Cloud point (1% in water) 40 ⁰ G refractive index at 50 ⁰ G 1.5143

2. Demulsifier R 11 from Japan

3. Dissolvan 441 from the FRG

The results obtained are shown in the following table. '

proces consumption separated amount of water (%) Demulgatoz E 11 : Dissolvan 4411 temperature ( ⁰ G) on reagent (ppm) 3 1 0 0 60 0 0 84.7 81.7 20 80.2 78.8 79.6 40 95.3 83.7 83.4 100 97.3 79.8 88.5 200 90.3

Example 2s

However, as Example 1, was left in the water bath with the difference that the oil heated in the thermostat at 40 ⁰ G, heated to 40 ⁰ g of distilled water were added and, after mixing with oil 2 hours at 40 ⁰ G. There were the following demulsifiers as

ο ο co

2% solutions in toluene in concentrations of 20, 40, 100 and 200 ppm (calculated on 100 % active substance) used and tested.

1. Oligomeric tXr-methylstyrenediol (substance S 2) with the following physicochemical characteristics: hydroxyl number (mg KOH / g) 140 molecular weight 680 functionality 1.7

2. Polyglycol ether of the oligomeric ^ -methylstyrenediol (Substance 1) prepared from 1 mol of oligomer o-methylstyrenediol (Substance S 2) and 15.7 mol of ethylene oxide with the physical-chemical characteristics given in Example 1.

3. Polyglycol ether of the oligomeric ^ -methylstyrenediol (Substance S 3) prepared from 1 mol of oligomeric o-methylstyrenediol (Substance S 2) and 10.7 mol of ethylene oxide having the following characteristics: hydroxyl number (mg KOH / g) 91.4

Refractive index at 50 ⁰ C 1.5566

Molecular weight 1049.5

4. Demulgarian Dissolan 441

5. Demulsifier R 11

Results are included in the following labeile #

proces consumption tungstem on reagent temperature (Ppm) ( ⁰ ) 40 20 40 100 200

separated amount of water (%)

S 1 S 2 S3 demulga- dissolving

gate R 11 van

4411

42.3 56.9 47.8 71.8 13.5

71.5 59.2 74.6 67.3 75.1

84.2 72.5 81.5 72.4 68.6

86 78.8 89 80.5 41.6

Example 3:

As in Example 2, but the amount of water separated is determined after 10, 30, 60 and 120 minutes. The following demulsifiers were used as 2% solutions in toluene in concentrations of 40 and 100 ppm (calculated on 100 % active substance) and tested

1. Polyglycol ethers of oligomeric-Cr-methyl-styrene-diol (substance S 1) prepared from 1 mol of oligomeric X.sub.x-methylstyrenediol (substance S.sub.2) and 15.7 mol of ethylene oxide having the characteristics given in example 1.

2. Polyglycol ethers of the oligomeric X-methylstyrenediol (Substance S 3), prepared from 1 mol of oliogerem sc-methylstyrenediol (Substance S 2) and 10.7 mol

Ethylene oxide with the characteristics given in Example 2.

3. Demulsifier Dissolvan 441

The results are included in the following table.

proces consumption settling secluded (%) amount of water tungstem to Eeagenz Time S 2 temperature (Ppm) (Min) S 1 Dissolvan ( ⁰ ) 0 4411 40 40 10 0 67.8 24 30 63.6 74.5 54.2 60 71.4 74.5 63.6 120 71.4 0 75.1 100 10 0 81.4 29.7 30 84.3 81.4 48.2 60 84.3 81.4 64.8 120 84.3 68.6

Example 4;

To determine the EestSalzgehaltes in demulsified petroleum oils were examined 24 hours after their treatment with the substances S 1, S 2, S3, demulsifier R 11 and Bissolvan 4411. For this purpose, 50 ml of petroleum were mixed with 40 ml of benzene and 100 ml of boiling water, 10 min. shaken and the aqueous phase separated in a separating funnel. The extraction with water was repeated three more times and combined the resulting aqueous fractions in a Maßkolben. Thereafter, 100 ml of this aqueous extract were titrated with 0.1 η mercury nitrate solution against diphenylcarbacid until the reaction to Blom and the amount of salt calculated as sodium chloride. Results are listed in the following table.

Used demulsifier Bestsalzgehalt after at a concentration 24 hours in mg / 1 of 40 ppm

Demulsifier E 11 321

Dissolvan 4411 335

S 1 193

S 2 386

S 3 287

- 10 -

Claims (1)

Inventions Process for the dewatering and desalting of petroleum emulsions by cleavage of the emulsions with nonionic emulsifiers, characterized in that oligomeric α-methylstyrene diol or polyglycol ethers of the oligomeric α-methylstyrene diol of the following formula ## STR4 ## are used as demulsifiers OH -O-OH-CH ₀ 4- OH-CH, a ι 2 CH CH Κ- " be used, where a = O to 15 Bthylenoxideinheiten and b = O to 6, preferably 2 to 4 ·, mean units and the d. - ^ ilethylstyroldiol a functionality between 1 and 2, preferably between 1.5 and 2, owns.