JPH06126104A - Demulsiying agent for electric demineralization - Google Patents

Abstract

PURPOSE:To provide a demulsifing agent to be used in electric demineralization of crude oil to efficiently remove water and impurities emulsified and dispersed in crude petroleum. CONSTITUTION:The demulsifying agent consist of, as a main component, a compound prepared by adding propylene oxide and ethylene oxide to a methyl benzyl compound, which is a condensate of an alkylphenol and formaldehyde, and then esterifying with an alkenylsuccinic acid and if necessary, a polyoxyalkylene, alkyl phenyl ether, alkylbenzenesulfonic acid salts, alkylnaphthalenesulfonic acid salts, etc. As a result, an electric demineralization apparatus whose function is not sufficiently pursued in a conventional way is operated practically efficiently by using the demulsifying agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a demulsifier for desalting crude oil, and more particularly to an aqueous solution of an inorganic salt existing in crude oil in the electric desalting step of crude oil which is carried out prior to the oil refining atmospheric distillation step. The present invention relates to a demulsifier for electrical desalination that enables effective removal of

[0002]

2. Description of the Related Art Generally, crude oil sent to refineries contains sodium chloride, which is caused by mixing formation water produced with oil in the oil production process in the oil field and seawater which is residual ballast water of tankers. Inorganic salts such as magnesium chloride and calcium chloride and mud are mixed. These are contained in crude oil in a crystalline state or as a precipitate, or are dissolved in water droplets in crude oil as an aqueous solution to be in a stable state.

When crude oil is supplied to a distillation apparatus as it is without removing inorganic salt from such crude oil, the salt is hydrolyzed to generate hydrochloric acid, so that a distillation column, a heat exchanger, a heater and piping are provided. Cause corrosion. In addition, it also causes scales and deposits to cause fouling, which causes an increase in differential pressure and also acts as a catalyst poison. As a result, in any case, adverse effects such as shortening of the operating period of the device and deterioration of product quality occur.

In order to solve these problems, it is necessary to separate water and impurities emulsified and dispersed in crude oil from crude oil. Therefore, conventionally, 2 to 20p for crude oil
After adding pm of a crude oil desalting demulsifier and adding 3 to 10% by weight of water to form a W / O type emulsion, an electric field is applied by an electric desalting device (Desalter) to separate oil and water. , The impurities are transferred to the aqueous phase and separated and removed. Conventionally, as the demulsifiers used here, for example, oxyalkylated phenol resins, carboxylic acids and polyalkylene glycols disclosed in JP-A-53-137883 and JP-A-51-53503. And polyesters, copolymers of ethylene oxide and propylene oxide, and mixtures thereof.

[0005]

In recent years, the necessity of treating heavy crude oil has increased, and accordingly, RFC for producing gasoline and middle distillates by decomposing heavy oil such as bottom oil of a distillation column.
The number of refineries installing disassembling devices such as C is increasing. However, when these heavy crude oils and heavy oils are desalted by an electric desalination unit, dewatering emulsifiers for crude oil desalination that have been conventionally used have poor oil-water separation and cause turbidity in the water layer, or treated crude oils. There is a problem that the salt content in the product exceeds the standard value.

[0006]

Means for Solving the Problems As a result of intensive studies to overcome the above-mentioned drawbacks of the prior art, the present inventors have found that a substance having a very limited specific chemical structure exhibits remarkable effects. The present invention has been completed. An object of the present invention is to provide a crude oil desalination aid having a good water recovery rate and a good desalination rate with a small addition amount by using an electric desalination apparatus together with heavy crude oil.

The addition amount of the electric desalination aid of the present invention is 20 to 500 pp with respect to crude oil when the electric desalination device is not used.
Although it is about m, when used in combination, the effect is exhibited with an extremely small addition amount of about 0.5 to 20 ppm.

The mechanism of action of the electrical desalination aid of the present invention is not always clear, but it is considered as follows. That is, the crude oil emulsion is a W / O type, and the naphthenic acid in the crude oil
Asphaltene, resin substances, etc. act as emulsifiers,
The interface between water droplets and oil forms a stable elasticity. The crude oil desalting aid acts on this elastic membrane to change its interfacial rheological properties, synergize with the action of the electric field, promote the destruction of the interfacial membrane, facilitate the coalescence of water droplets, facilitate aggregation, and separate oil and water. Will be interpreted as.

[0009]

INDUSTRIAL APPLICABILITY As described above, in the desalination treatment of heavy crude oil and heavy oil according to the present invention, the electric desalination technology, which has not been substantially used sufficiently, can be substantially treated by the aid of the present invention. For the first time, it was possible to make it an effective technology.

[0010]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. 1: Crude oil used in the test AH 33.3%, AM 37.5, KF 29.2%,
BS & W 1.5%, water content 0.5%, salt content 89ppm

2. Test method and conditions Procedure conditions 1. Collect crude oil Mix the crude oil container on a shaker for 10 minutes. ↓ Collect 75 ml of crude oil into a 100 ml centrifuge tube. Addition of chemicals Addition with 10% diluted solution ↓ 3. Crude oil / drug mixture Hand shaking 50 times ↓ 4. Preheat 90 ℃ x 20 minutes ↓ 5. Uniformization of crude oil Hand shaking 50 times ↓ 6. Injection of wash water Tests 1, 2: 3.0 ml, Test 3: 3.1 ml ↓ 7. Mixing crude oil / wash water Hand shaking 200 times ↓ 8. Voltage application treatment 2000V x 2 minutes (90 ° C) ↓ 9. Standing (90 ° C) 5, 15, 30, 45 minutes Measure the amount of separated water after standing, ↓ Calculate dehydration rate 10. Analysis Salinity in desalted crude oil

FIG. 1 shows an apparatus in which the test of the present invention has been conducted, which shows the same performance as that of an actual electric desalination apparatus in a refinery.

Table 1 shows the results when 5 ppm of various demulsifiers were added. Demulsifiers differ in the type of compound, molecular weight, number of moles of ethylene oxide added, and the like.

[0014]

* 1: The molecular weight of the condensate calculated by excluding the polyoxyalkylene chain from the chemical structure * 2: ◎ Very good (completely divided into two layers) ○ Good (completely divided into two layers) There is some turbidity in the water layer) △ Somewhat bad (emulsion layer is observed between oil layer and water layer) × Poor (thick emulsion layer exists between oil layer and water layer) * 3: Polyoxyethylene Dodecenyl succinic acid monoester of α-methylbenzylated nonylphenyl ether formalin condensate * 4: polyoxyethylene-polyoxypropylene dodecenylsuccinic acid monoester of α-methylbenzylated nonylphenyl ether formalin condensate * 5: ethylene oxide Propylene oxide copolymer * 6: Polyalkylene glycol carboxylic acid ester * 7: Polyester Oxyethylene - polyoxypropylene phenol formaldehyde condensate * 8: polyoxyethylene nonylphenol-formaldehyde condensate

[0016]

Examples 2 to 5 Similar tests to those of Example 1 were carried out using the desalting agents shown in Table-1, and the results are shown in Table-2.

[0017]

[Comparative Examples 1 to 8] Similarly, tests using desalting agents C, D, E, and F and comparative tests without adding desalting agents were conducted, and the results are shown in Table 1 together with Examples.

[0018]

[Brief description of drawings]

FIG. 1 is a sectional view of an electric desalination test apparatus used in Examples. 1: High voltage generator 2: Electrode 3: Glass container 4: Constant temperature bath 5: Temperature indicator

[0019]

[Figure 1]

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[Procedure amendment]

[Submission date] November 10, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an electric desalination apparatus used in Examples.

[Explanation of reference numerals] 1: High-voltage generator, 2: Electrode, 3: Glass container, 4: Constant temperature bath, 5: Temperature indicator

Claims (1)

[Claims] 1. Compounds A and B represented by the following general formula:
C, D, E, and F are A: B: C: D: E: F = 10 to 1
00:00 to 9: 0 to 9: 0 to 90: 0 to 9: 0
Desalting demulsifier for crude oil, which is contained in a ratio of 90. -Compound A A compound in which an alkylene oxide adduct of a formalin condensate of an alkylphenol is styrenated and then esterified with an alkenylsuccinic anhydride. [Chemical 1] However, in the formula, EO is --CH ₂ --CH ₂ --O-- and PO is-
CH ₂ --CH (CH ₃ ) O--, R ₁ is an alkyl group having 5 to 20 carbon atoms (average 9), k is 2 to 20 (average 10), and n is 2
.About.20 (10 on average) are shown. ASA is Where k is 2 to 20 average 10, n is 2 to 20 average 10, p is 0 to 5 average 2, and a and b are 0 or 1 (however, a + b is 1 or more). -Compound B Polyoxyalkylene polyglycol. HO (EO) b (PO) a (EO) bH a is 15 or more, and b is 20 to 9 in the ratio of EO chains in the product.
A polyalkylene polyglycol having a numerical value of 0%.・ Compound C Polyglycol ester a and b are the same as compound B.・ Compound D Alkylphenol / formaldehyde polycondensation alkylene oxide adduct [Chemical Formula 2] However, in the formula, a is 2 to 15 and EO is --CH ₂ --CH ₂ --O.
-, R ₁ is an alkyl group having up to 14 carbon atoms, and n is 1 to 1
3 or more are shown respectively. Compound E Alkylphenol / formaldehyde / alkanolamine polycondensation alkylene oxide adduct [Chemical Formula 3] (A) (B) R ₁ is an alkyl group having 4 to 12 carbon atoms, R ₂ is --CH ₂ --C
H ₂ --O-- or --CH ₂ --CH (CH ₃ ) O--
The condensation molar ratio of A and B is 1: 1 to 10: 1, and the ratio of EO is 10 to 60% of the product. Alkylimidazoline salts of any of the compounds of formula A A B [Chemical 5] However, R is an alkyl group having 10 to 30 carbon atoms, and n is 1 to 3
Is a positive number, R'is an alkyl group having 3 to 10 carbon atoms, and m is 1
4 is a positive number, R "is an alkyl group having 1 to 10 carbon atoms, and M is-.
Indicating H or -CH ₂ CH ₂ NH ₂ or -CH ₂ CH ₂ OH, respectively.