JP2001162107A - Oil separating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the moisture content in an oil layer and to make effective use of sludge by separating efficiently the moisture content in the sludge staying on the bottom of a crude oil tank. SOLUTION: This oil separating agent contains, as principal components, a nonion surfactant A having 8-15 HLB value and an alkylene oxide adduct B of an alcohol containing 10-80 mass % oxyethylene group and having 1,000-20,000 weight average molecular weight or B and a quaternary ammonium compound C having at least one of 8-24C alkyl and alkenyl groups.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil / water separating agent for separating an emulsion of oil and water into oil and water, thereby reducing the water content in the oil and effectively utilizing the oil.

[0002]

2. Description of the Related Art Crude oil is emulsified by asphaltene or the like contained in crude oil during transportation or storage due to water contamination or dew condensation, and is deposited on the bottom of a crude oil tank to form so-called sludge. Become.

For this reason, the crude oil tank is required to be inspected once every 7 to 10 years. At that time, it is necessary to completely discharge the sludge. The cost and the difficulty of the operation are problems, and a processing method that does not cost much is desired.

[0004] On the other hand, such sludge often accounts for 10% or more of crude oil, and the moisture contained therein may be 10% or more of bottom sludge. Therefore, it is necessary to remove water in the sludge as much as possible and reuse it as a crude oil component.

[0005] That is, if the oil content is high, when used as a fuel or the like, combustion calories are reduced, water causes problems such as corrosion of pipes and tanks, and oil-water separation efficiency in a crude oil refining process is reduced. Therefore, it is considered that the content of water in the crude oil is desirably 0.5% or less.

In view of the above, as a sludge treatment method, a special cleaning liquid is forcibly dispersed in crude oil in a tank while stirring with a jet nozzle into sludge deposited on the bottom of the tank, and treated together with crude oil. Alternatively, a method has been proposed in which crude oil is ejected from a jet nozzle after removing crude oil in a tank to break sludge and flow out to the outside.In each of these methods, sludge is diluted with crude oil. And does not reduce the water content in the sludge.

On the other hand, if the water content in the sludge can be reduced by a chemical method before the above-mentioned processing methods such as stirring and washing by a machine, the mechanical processing cost can be reduced and the crude oil can be effectively used. Can be measured.

As such a method, there has been proposed a method in which sludge is heated or diluted with a small amount of crude oil or mineral oil to lower the viscosity, and then separated by adding a demulsifier. In this case, as the demulsifier, an alkylene oxide adduct of alkylphenol, a formaldehyde condensate of an alkylene oxide adduct of alkylphenol, a block copolymer of an ethylene oxide group / propylene oxide group containing an alkyl group, a dialkyl sulfosuccinate, a polyoxyethylene sorbitol fatty acid ester,
Many surfactants have been proposed and are still being used, such as polyoxyalkylene glycerol fatty acid esters.

[0009] Specifically, JP-A-3-229682 proposes that a polyoxyethylene nonylphenol formaldehyde condensate or a polyoxyethylene / polyoxypropylene block copolymer is effective as a demulsifier. Also, JP-A-8-2
No. 3,1984, proposes a method of using a crude oil treating agent having a water number of 2 to 10 with an alkylene oxide adduct of a formalin condensate of an alkylphenol, but none of them has a sufficient oil-water separation effect.
Further improvement and development was desired.

[0010] The present invention has been made in view of the above circumstances, and an oil / water separating agent for efficiently separating an emulsion of oil and water into oil and water to reduce the water content in the oil and to make effective use as an oil. The purpose is to provide.

[0011]

Means for Solving the Problems and Embodiments of the Invention The present inventors have made intensive studies to achieve the above object, and as a result, (A) a nonionic surfactant having an HLB of 8 to 15; B) containing 10 to 80% by mass of oxyethylene groups,
And an oil / water separator mainly containing an alkylene oxide adduct of an alcohol having a weight average molecular weight of 1,000 to 20,000, or (C) an alkylene oxide adduct of the alcohol of component (B) and (C) an alkyl having 8 to 24 carbon atoms. And a quaternary ammonium compound having at least one alkenyl group, the oil-water separator has a high oil-water separation rate and can greatly reduce the water content in the oil by the action of these components. The present invention has been found to reduce the cost and the difficulty of the operation, and to be able to effectively use the crude oil.

Accordingly, the present invention firstly provides (A) HLB
Contains, as main components, a nonionic surfactant having a molecular weight of 8 to 15, and (B) an alkylene oxide adduct of an alcohol containing 10 to 80% by mass of oxyethylene groups and having a weight average molecular weight of 1,000 to 20,000. Second, (B) an oxyethylene group having 10
-80% by mass, and the weight average molecular weight is 1000-2.
An oil-water separator comprising, as main components, an alkylene oxide adduct of an alcohol of 0000 and (C) a quaternary ammonium compound having at least one alkyl or alkenyl group having 8 to 24 carbon atoms. I will provide a.

Hereinafter, the present invention will be described in more detail.
The oil-water separation agent according to the first invention of the present invention comprises (A) a nonionic surfactant having an HLB of 8 to 15, (B) an oxyethylene group of 10 to 80% by mass, and a weight average molecular weight of 1
And 2,000 to 20,000 alcohol alkylene oxide adduct.

Here, the nonionic surfactant of the component (A) has an HLB of 8 to 15, preferably an HLB.
Is 10-14. If the HLB is out of the above range, no fluidization occurs and no separation between the oil phase and the aqueous phase occurs.

[0015] Such nonionic surfactants include:
For example, ethylene oxide adduct of dodecyl ether,
Nonylphenol ethylene oxide adduct, polyoxyalkylene alkyl ether, polyoxyalkylene alkyl phenol ether, polyoxyalkylene alkyl fatty acid ester, polyoxyalkylene allyl phenol ether, polyoxyalkylene sorbitan fatty acid ester, polyoxyalkylene alkylamine, sorbitan fatty acid ester, Polyoxyalkylene and the like can be mentioned, and one of these can be used alone or in combination of two or more.

The oxyethylene group of the component (B) is 10
-80% by mass, and the weight average molecular weight is 1000-2.
The alkylene oxide adduct of the alcohol 0000 is obtained by adding an alkylene oxide group to a monohydric or polyhydric alcohol (for example, propylene glycol, glycerin, diglycerin, arabitol, sorbitol, erythritol, butanol, stearyl alcohol, lauryl alcohol, etc.). The alkylene oxide group includes an oxyethylene group and an oxypropylene group, and particularly, the oxyethylene group is 10 to 10 in the total molecular weight.
It is necessary to be 80% by mass, preferably 20 to
50% by mass. If the number of oxyethylene groups is too large, the hydrophilicity is too large to be adsorbed on the oil, and the aggregation of the oil by the oil-water separating agent is inhibited. On the other hand, if the amount is too small, the hydrophobicity is too large, so that the oil / water separating agent itself aggregates, and the oil aggregation effect is not exhibited.

The weight average molecular weight of the alkylene oxide adduct of alcohol of component (B) is from 1,000 to 2,000.
0, especially 750 to 10,000. If the weight average molecular weight is too small, the aggregation effect will be low, while if it is too large, the solubility in water will be poor and the effect cannot be exhibited.

Examples of the alkylene oxide adduct of alcohol as the component (B) include, for example, ethylene oxide propylene oxide block copolymer of propylene glycol, ethylene oxide propylene oxide block copolymer of glycerin or diglycerin, and arabitol or sorbitol. Examples include an ethylene oxide propylene oxide block copolymer.

The amounts of the components (A) and (B) added are
Component (A) is 100 to 1 with respect to 100 parts by mass of crude oil sludge.
200 ppm, component (B) is 20 to 500 ppm, and the ratio of component (A) / component (B) is 1 by weight.
-5, preferably 1-3. If the addition amount of the component (A) is too large, the oil-water separation ability may decrease because it acts as an emulsifier. On the other hand, if the addition amount of the component (B) is too large, it works as a dispersant and the oil-water separation ability may be reduced. May decrease. The ratio of the component (A) to the component (B) differs depending on the properties of the sludge. However, when the component (B) is more than the component (A), the dispersing effect of the component (B) becomes stronger, and oil-water separation is performed. The effect may not be exhibited.

Next, the oil / water separating agent according to the second invention of the present invention comprises (B) an alkylene oxide adduct of an alcohol containing 10 to 80% by mass of oxyethylene groups and having a weight average molecular weight of 1,000 to 20,000. And (C) a quaternary ammonium compound having at least one alkyl group or alkenyl group having 8 to 24 carbon atoms.

Here, as the component (B), the same one as in the first invention can be used.

The quaternary ammonium compound having at least one alkyl or alkenyl group having 8 to 24 carbon atoms of the component (C) includes those represented by the following general formula (1).

Embedded image [In the formula, at least one of R ¹ , R ² , R ³ , and R ⁴ is an alkyl group or alkenyl group having 8 to 24 carbon atoms, and the rest is an alkyl group having 1 to 3 carbon atoms, or − (R
⁵ O) _n H (wherein, R ⁵ is an alkylene group having 2 to 4 carbon atoms;
n is 1-10. ) Indicates, X ^- represents a counter anion such as a halide ion. ]

In the above formula (1), R ¹ , R ² , R ³ and R ⁴ are
At least one of them is a linear or branched alkyl or alkenyl group having 8 to 24, preferably 12 to 18 carbon atoms, and a part of the alkyl or alkenyl group is substituted with a hydroxyl group. And the alkyl group and the alkenyl group may be a mixed alkyl group or a mixed alkenyl group. If the carbon number is less than 8, the oil-water separation effect is poor, while if it exceeds 24, the solubility and dispersibility in the oil-water emulsion are poor.

The above R ¹ , R ² , R ³ , and R ^{4 have} 8 to 8 carbon atoms.
Remainder other than alkyl or alkenyl group 24, an alkyl group (e.g. methyl, ethyl) having 1 to 3 carbon atoms or - shows the (R ⁵ O) _n H.

In the formula-(R ⁵ O) _n H, R ⁵ has 2 to 4 carbon atoms.
And examples thereof include an ethylene group, a propylene group, and an isopropylene group. n is 1-10.

[0026] X ^- represents fluorine ion, a chlorine ion, a halide ion such as a bromine ion, a sulfate ion, a phosphate ion, a counter anion such as acetate ion.

Examples of such quaternary ammonium compounds include dicocoalkyldimethylammonium chloride, dioleyldimethylammonium chloride, cocoalkyltrimethylammonium chloride, lauryltrimethylammonium chloride, di (polyoxyethylene) monococoalkylmonomethylammonium chloride. And the like.

In the oil-water separating agent according to the second invention of the present invention, the amounts of the components (C) and (B) are 100
20 to 500 ppm of the component (B) based on parts by mass,
The component (C) is 100 to 700 ppm, and the component (C)
The ratio of component / (B) is 1 to 5, preferably 1 to 3, by weight. If the added amount of the component (B) is too large, it acts as a dispersant, and the oil-water separation ability may be reduced. On the other hand, if the added amount of the component (C) is too large, the charge of the sludge becomes excessive and the oil-water separation ability is reduced. May decrease. Also,
When the component (B) is more than the component (C), the dispersing effect of the component (B) becomes strong, and the oil-water separation effect may not be exhibited.

In the present invention, (A),
In addition to the oil-water separating agent containing the component (B) as a main component and the oil-water separating agent containing the components (B) and (C) of the second invention as a main component, the components (A), (B), and (C) An oil / water separating agent containing a component as a main component can also be suitably used. In this case, the added amount of the components (A) to (C) is
Component (A) is 100 to 1200 pp with respect to 0 parts by mass.
m, component (B) is 20 to 500 ppm, component (C) is 1
It is 00 to 700 ppm.

The oil / water separating agent of the present invention may contain, in addition to the above components (A) to (C), other additives such as various antioxidants, combustion improvers, antiknock agents, pour point depressants. Can be used in combination, and other surfactants can be used in combination as long as the performance of the oil-water separation agent of the present invention is not impaired.

The oil-water separation agent of the present invention is obtained by
Alternatively, it can be added by dissolving it in various solvents, but it is effective to add it in a solvent solution dissolved in the solvent. As such a solvent, an aromatic mineral oil, a petroleum solvent or a mixture thereof is used. The addition amount of these solvents is 500 to 5000 ppm, preferably 1000 ppm, based on crude oil sludge.
３3000 ppm.

Using the oil-water separating agent of the present invention, sludge retained at the bottom of a crude oil tank can be treated and regenerated as follows.

In the method for treating and regenerating sludge, the sludge retained at the bottom of the crude oil tank is heated to about 50 to 60 ° C., a predetermined amount of the oil / water separating agent of the present invention is added, and the mixture is stirred well and thoroughly. To the sludge evenly. Thereafter, the sludge is allowed to stand at 50 to 60 ° C. and separated into oil and water. After confirming the water content in the oil layer, the oil layer within the standard is recycled.

The oil / water separating agent of the present invention can be applied to an oil / water mixed liquid generated when pumping oil from an oil well or a hydrous sludge generated when a crude oil tank is washed.

[0035]

According to the oil-water separating agent of the present invention, the water in the sludge retained at the bottom of the crude oil tank can be efficiently separated to significantly reduce the water in the oil layer.
Sludge can be effectively used.

[0036]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[Examples 1 and 2] Crude oil sludge (moisture 10
%) As a sample, and 70 ml of the sample heated to 55 ° C.
Take it in a cylinder with a scale of 0 ml, and use the following (A),
The component (B) was added in the amount shown in Table 1, stirred at 1200 rpm for 1 minute, mixed, and allowed to stand in a 55 ° C constant temperature bath for 24 hours. Component (A): Ethylene oxide adduct of dodecyl ether (HLB = 13.0) Component (B): Ethylene oxide propylene oxide block copolymer of propylene glycol (30% of EO in total molecule, molecular weight of PO) : 3250)

The oil-water separation rate of the obtained sample and the water content in the separated oil layer were measured. Table 1 shows the results. The water content in the crude oil emulsion was determined by a distillation method according to JIS K2275. Oil / water separation rate The oil / water separation rate was calculated by the following equation from the amount of water separated and the amount of water in the emulsion measured in advance according to JIS K2275.

(Equation 1)

Examples 3 and 4 The oil-water separation rate and the water content in the separated oil layer were measured in the same manner as in Example 1 except that the following components (A) and (B) were used. Table 1 shows the results. Component (A): Nonylphenol ethylene oxide adduct (HLB = 13.3) Component (B): Propylene glycol ethylene oxide Propylene oxide block copolymer (Ratio of EO in total molecule: 50%, molecular weight of PO: 2250)

Examples 5 and 6 The oil / water separation rate and the water content in the separated oil layer were measured in the same manner as in Example 1 except that the following components (B) and (C) were used. Table 1 shows the results. Component (B): propylene glycol ethylene oxide propylene oxide block copolymer (proportion of EO in total molecule: 30%, molecular weight of PO: 3250) Component (C): dioleyl dimethyl ammonium chloride (R ¹ and R ²⁾ : Oleyl)

Examples 7 and 8 The oil-water separation rate and the water content in the separated oil layer were measured in the same manner as in Example 1 except that the following components (B) and (C) were used. Table 1 shows the results. Component (B): ethylene oxide propylene oxide block copolymer of propylene glycol (proportion of EO in total molecule: 50%, molecular weight of PO: 2250) Component (C): dicocoalkyldimethylammonium chloride (R ¹ and R ² : Palm alkyl)

[Comparative Example] The following No. 1-8
Example 1 was repeated except that the oil-water separator was used in the amount shown in Table 2.
The oil-water separation rate was measured in the same manner as in the above. Table 2 shows the results.

No. 1: Ethylene oxide adduct of nonylphenol (HLB = 10) 2: Ethylene oxide adduct of nonylphenol (HLB = 13) No. 3: Ethylene oxide adduct of nonylphenol formalin condensate (HLB = 10) No. 4: Ethylene oxide adduct of formalin condensate of nonylphenol (HLB = 13) 5: Propylene glycol ethylene oxide propylene oxide block copolymer (E in total molecule)
O ratio: 10%, PO molecular weight: 3850) 6: Ethylene oxide propylene oxide block copolymer of propylene glycol (E in the total molecule)
O ratio: 10%, PO molecular weight: 3250) 7: Dioleyldimethylammonium chloride (R ₁ , R ₂ = oleyl) 8: Ethylene oxide propylene oxide block copolymer of propylene glycol (E in the total molecule)
O ratio: 30%, PO molecular weight: 3250)

[0044]

[Table 1] * Aromatic solvents: Exxon Solvesso

[0045]

[Table 2] From the results of Tables 1 and 2, the oil-water separators of Examples 1 to 8 exhibited excellent oil-water separation rates as compared with Comparative Examples (Nos. 1 to 8) in which the components (A) to (C) were added alone. It is recognized that it has excellent oil-water separation effect.

Claims (2)

[Claims] 1. A nonionic surfactant having an HLB of 8 to 15 and (B) an oxyethylene group of 10 to 80% by mass.
An oil-water separating agent comprising, as a main component, an alkylene oxide adduct of an alcohol having a weight average molecular weight of 1,000 to 20,000. (B) an oxyethylene group content of 10 to 80% by mass and a weight average molecular weight of 1,000 to 20,000
An alkylene oxide adduct of an alcohol,
(C) A quaternary ammonium compound having at least one alkyl group or alkenyl group having 8 to 24 carbon atoms, and a quaternary ammonium compound as a main component.