CN111647397B

CN111647397B - Acid sludge recycling method and oil displacement surfactant

Info

Publication number: CN111647397B
Application number: CN202010383652.3A
Authority: CN
Inventors: 关丹; 栾和鑫; 阙庭丽; 陈权生; 唐文洁; 云庆庆; 帕提古丽·麦麦提; 焦秋菊
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2020-05-08
Filing date: 2020-05-08
Publication date: 2023-02-10
Anticipated expiration: 2040-05-08
Also published as: CN111647397A

Abstract

The invention provides a recycling method of acid sludge and an oil displacement surfactant. The recycling method comprises the following steps: carrying out sulfonation reaction on the acid sludge and heavy alkylbenzene to obtain heavy alkylbenzene sulfonic acid; neutralizing heavy alkylbenzene sulfonic acid to obtain heavy alkylbenzene sulfonate; and mixing the heavy alkylbenzene sulfonate with KPS to obtain the oil-displacing surfactant. The acid sludge and the heavy alkylbenzene are subjected to addition reaction to sulfonate the heavy alkylbenzene to obtain heavy alkylbenzene sulfonic acid; then the heavy alkylbenzene sulfonic acid is neutralized to obtain heavy alkylbenzene sulfonate, and then the heavy alkylbenzene sulfonate is compounded with the existing KPS to obtain the novel oil-displacing surfactant. The recycling method realizes more thorough utilization of acid sludge, realizes harmless recycling of wastes, and eliminates the outdated method of burning and burying which pollutes the environment.

Description

Acid sludge recycling method and oil displacement surfactant

Technical Field

The invention relates to the field of tertiary oil recovery of oil fields, in particular to a recycling method of acid sludge and an oil displacement surfactant.

Background

The acid sludge is acid sludge produced in the sulfuric acid refining process for producing petroleum sulfonate and petroleum product in alkylation in oil refinery, and is inorganic sulfuric acid, organic sulfonic acid and other matter. Wherein, sulfonation is an important process for preparing alkyl sulfonate, and sulfur trioxide is widely applied to the sulfonation process of petroleum sulfonate, and a large amount of acid sludge is generated after sulfonation due to strong activity of sulfur trioxide. The acid sludge contains unreacted acid substances such as sulfuric acid and the like, and harmful substances such as compounds, sulfonated substances, sulfides, nitrides and the like, and if the acid sludge is not properly treated, the acid sludge directly or indirectly pollutes the environment by taking the atmosphere, water or soil as a medium.

In the prior art, acid sludge is treated mainly by common modes such as incineration, burying, sodium hydroxide neutralization and the like, and the common modes can cause atmosphere, soil and water pollution. The preparation of ammonium sulfate by the reaction of acid sludge and ammonia water has no economic benefit due to high production cost. The literature reports that the acid sludge is used for producing the road asphalt. The acid sludge and powdered rock phosphate are reacted to produce phosphate fertilizer containing calcium dihydrogen phosphate, calcium phosphate, etc. but the air pollution is still caused during the process of producing phosphate fertilizer. There are also reports on the use of acid sludge as a retarder water reducer and air entraining agent for concrete.

In view of obvious harm of acid sludge to the environment, the harmless utilization of the acid sludge needs to be carried out urgently, but no relevant report exists in the prior art on how to effectively and harmlessly recycle the acid sludge.

Disclosure of Invention

The invention mainly aims to provide a recycling method of acid sludge and an oil-displacing surfactant, so as to solve the problem that the acid sludge treatment method in the prior art is harmful to the environment.

In order to achieve the above object, according to an aspect of the present invention, there is provided a recycling method of acid sludge, the recycling method including: carrying out sulfonation reaction on the acid sludge and heavy alkylbenzene to obtain heavy alkylbenzene sulfonic acid; neutralizing the heavy alkylbenzene sulfonic acid to obtain heavy alkylbenzene sulfonate; and mixing the heavy alkylbenzene sulfonate with KPS to obtain the oil-displacing surfactant.

Further, in the sulfonation reaction, the mass ratio of acid sludge to heavy alkyl benzene is (3); preferably, the temperature of the sulfonation reaction is 70 to 80 ℃, and the reaction time is 6 to 8h.

Further, neutralizing heavy alkylbenzene sulfonic acid to obtain heavy alkylbenzene sulfonate comprises: adding alkali into heavy alkyl benzene sulfonic acid to neutralize until the pH value is 8~9, and obtaining a neutralized product; and (4) sequentially extracting and dehydrating the neutralized product to obtain the heavy alkylbenzene sulfonate.

Further, the neutralization products are sequentially extracted by any one of the following extracting agents: petroleum ether, diethyl ether, acetone, cyclohexane, ethyl acetate or hexane to obtain extract; the extract is subjected to azeotropic dehydration by adopting any one of the following entrainers to obtain the heavy alkylbenzene sulfonate: toluene, xylene, isobutanol, chlorohydrin, pyridine or formic acid.

Further, the extraction temperature of the extractant is 60 to 90 ℃.

Further, the heavy alkylbenzene is a mixture of olefin and aromatic hydrocarbon structures obtained after oligomerization of propylene, and has a carbon chain branching structure, and the length of the carbon chain is more than 22 and less than 33.

Further, after azeotropic dehydration and before obtaining the heavy alkylbenzene sulfonate, the recycling method further comprises: the product after azeotropic dehydration is extracted with ethanol, propanol, acetone or isopropanol.

Further, mixing the heavy alkylbenzene sulfonate with KPS according to the mass ratio of 1 to 1.

In order to achieve the above object, according to a second aspect of the present invention, there is provided a flooding surfactant prepared by any one of the above recycling methods.

According to a third aspect of the present invention, there is provided a binary oil-displacing surfactant comprising a polymer and an oil-displacing surfactant prepared by any of the above recycling methods.

By applying the technical scheme of the invention, the heavy alkylbenzene sulfonic acid is obtained by carrying out sulfonation reaction on the acid sludge and the heavy alkylbenzene, a good anionic surfactant is prepared after neutralization, the surfactant and petroleum sulfonate form a new oil displacement surfactant, and the surfactant and the polymer surfactant are compounded to obtain a good interfacial tension effect. The invention realizes the harmless reutilization of acid sludge, and converts the acid sludge into a good binary composite flooding system for oil displacement. The method has simple and feasible process, low requirement on equipment, no discharge of three wastes in the treatment process, complete accordance with the requirement of environmental protection and good social and economic benefits.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a graph showing the results of interfacial tension measurements of binary flooding surfactants according to examples 1 to 3 of the present invention;

fig. 2 is a graph showing the results of viscosity measurements of a flooding system of the binary flooding surfactant according to examples 1 to 3 of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

Heavy alkylbenzene: the heavy alkylbenzene is a mixture of olefin and aromatic hydrocarbon structures obtained after oligomerization of propylene, and is called heavy alkylbenzene with a carbon chain branched structure, wherein the carbon chain length is more than 22 and less than 33.

In an exemplary embodiment of the present application, there is provided a new method for recycling acid sludge, the method comprising: carrying out sulfonation reaction on the acid sludge and heavy alkylbenzene to obtain heavy alkylbenzene sulfonic acid, and neutralizing the heavy alkylbenzene sulfonic acid to obtain heavy alkylbenzene sulfonate; and mixing the heavy alkylbenzene sulfonic acid with KPS to obtain the oil displacement surfactant.

The acid sludge recycling method realizes the sulfonation of the heavy alkylbenzene by the addition reaction of the acid sludge and the heavy alkylbenzene to obtain the heavy alkylbenzene sulfonic acid; then the heavy alkylbenzene sulfonic acid is neutralized to obtain heavy alkylbenzene sulfonate, and then the heavy alkylbenzene sulfonate is compounded with the existing KPS to obtain the novel oil-displacing surfactant. The recycling method realizes more thorough utilization of acid sludge, realizes harmless recycling of wastes, and eliminates the outdated method of burning and burying which pollutes the environment.

The heavy alkylbenzene in the application is a mixture of olefin and aromatic hydrocarbon structures obtained after oligomerization of ethylene and propylene, and has a carbon chain branching structure, and the length of the carbon chain is more than 22 and less than 33.

In the recycling method, the reaction ratio of the acid sludge and the heavy alkylbenzene can be reasonably adjusted according to the content of the sulfuric acid. In a preferred embodiment of the present application, in the addition reaction, the mass ratio of acid sludge to heavy alkyl benzene is 3. Preferably, the temperature of the sulfonation reaction is 70 to 80 ℃, and the reaction time is 6 to 8h.

In a preferred embodiment, the heavy alkylbenzene sulfonic acid is neutralized to provide a heavy alkylbenzene sulfonate comprising: adding alkali into heavy alkyl benzene sulfonic acid to neutralize until the pH value is 8~9, and obtaining a neutralized product; and (4) sequentially extracting and dehydrating the neutralized product to obtain the heavy alkylbenzene sulfonate.

The product after sulfonation reaction is neutralized by adding alkali, and the pH value after neutralization is preferably controlled within the range of 8~9, so that the pH value of the acid residue reaction mixed liquid after neutralization by the alkali is slightly alkaline, and the synergistic effect of the heavy alkylbenzene sulfonate serving as a surfactant and other surfactants is facilitated. In a preferred embodiment of the present application, the pH after neutralization is 9. Preferably, the extractant for extracting the neutralized product is selected from petroleum ether, diethyl ether, cyclohexane, ethyl acetate or hexane; preferably, the temperature of extraction is 60 to 90 ℃. The above-mentioned extractant is selected in consideration of extraction effect and price. The extraction temperature is controlled to be 60-90 ℃, so that the effective substances can be extracted to the maximum extent by considering the higher extraction temperature, and the beneficial effect of the maximum yield of the effective substances is achieved in the temperature range.

The extraction step is to extract the effective components in the reactant to the maximum extent. In order to further improve the purity of the product, in another preferred embodiment, the neutralized product is extracted sequentially with any one of the following extracting agents: petroleum ether, diethyl ether, acetone, cyclohexane, ethyl acetate or hexane to obtain extract; the extract is subjected to azeotropic dehydration by adopting any one of the following entrainers to obtain the heavy alkylbenzene sulfonate: toluene, xylene, isobutanol, chlorohydrin, pyridine or formic acid. Further azeotropic dehydration is carried out through toluene and the like to obtain a final purified product, which is beneficial to calculating the content of the effective components.

In order to further increase the purity of the heavy alkylbenzene sulfonate, in a preferred embodiment of the present application, the recycling method further comprises, after azeotropic dehydration and before obtaining the heavy alkylbenzene sulfonate: the product after azeotropic dehydration is extracted with ethanol, propanol, acetone or isopropanol.

In view of the relatively poor emulsifying property of the heavy alkyl sulfonic acid obtained by recycling, in a preferred embodiment of the present application, the oil displacing surfactant is obtained by mixing the heavy alkyl benzene sulfonic acid with KPS in a mass ratio of 1 to 1. The heavy alkylbenzene sulfonic acid obtained by the acid residue sulfonation reaction is compounded with the existing KPS surfactant, so that the emulsifying property can be improved, and the interfacial tension can be reduced, thereby obtaining the surfactant with excellent performance by compounding.

In a second exemplary embodiment of the present application, a flooding surfactant is provided, which is prepared by any one of the above recycling methods, and has an interfacial tension of 2.96 × 10 ^-3 mN/m。

In a third exemplary embodiment of the present application, a binary oil-displacing surfactant is provided, which includes a polymer and any one of the oil-displacing surfactants prepared by the above recycling methods. The surface tension of the obtained binary flooding system surfactant is 2.96 multiplied by 10 according to the source or the batch of acid sludge ^-3 mN/m ~6.13×10 ^-3 mN/m. After being mixed with the polymer, the oil displacement system viscosity can be increased, and the oil displacement efficiency can reach more than 20 percent. The good performance of the novel surfactant was demonstrated.

The advantageous effects of the present application will be further described with reference to specific examples.

Example 1

1. The reaction of acid sludge and heavy alkylbenzene comprises the following steps:

(1) 30g of acid sludge is accurately weighed and added into a beaker, 1L of distilled water is added and stirred.

(2) Mixing the acid sludge in the step (1) with heavy alkylbenzene according to the mass ratio of 3:2, heating and stirring at the temperature of 70 ℃ for reaction for 8 hours.

(3) Waiting until the sample in step (2) was well mixed and neutralized to pH =9 with 30% NaOH solution.

(4) To the solution in step (3) was slowly added 100mL of petroleum ether at a temperature of 60 ℃ to 90 ℃ for extraction, and the solution was partitioned into an upper layer and a lower layer.

(5) And (4) adding 100g of toluene into the lower layer in the step (4), performing azeotropic dehydration, and drying at 95 ℃ to constant weight to obtain 26.35g of earthy yellow solid.

(6) And (5) extracting the reactant in the step (5) by using a 50% ethanol solution to obtain a crude oil-displacing surfactant.

(7) And (3) mixing the crude product in the step (6) with petroleum sulfonate according to a mass ratio of 1:1 to obtain the novel surfactant for oil displacement.

(8) The interfacial tension of the surfactant in the step (7) can reach 2.96 multiplied by 10 through SY/T5370-2018 standard detection ^-3 mN/m, which is mixed with a polymer (in this embodiment, the polymer 1 is partially hydrolyzed polyacrylamide, or may be replaced with another polymer, for example, the polymer 2 is an AM/AHPE copolymer with a comb-shaped molecular structure and an ultrahigh relative molecular mass, the polymer 3 is a core-shell associated polymer HBPAM provided by the petroleum university in southwest, and the polymer 4 is a sixteen-arm star-shaped polycaprolactone polymer, where the average molecular weights of the four polymers are 2500 ten thousand), so that the viscosity of the flooding system can be increased, and the flooding efficiency can reach more than 20%. Exhibit the good properties of the novel surfactants.

2. Sample detection

The interfacial tension is shown in FIG. 1 and the viscosity is shown in FIG. 2. Wherein the interfacial tension is measured according to SY/T5370-2018 standard, and the viscosity is measured according to Q/SY 119-2014. The oil displacement efficiency is shown in table 1.

Example 2

The procedure of example 1 was followed except that the test acid sludge sample (batch 2) was different. The interfacial tension of the KPS novel binary composite flooding is measured to be 3.42 multiplied by 10 ^-3 mN/m, can increase the viscosity of an oil displacement system after being mixed with the polymer, and the oil displacement efficiency reaches more than 20 percent. The results are shown in FIG. 1, FIG. 2, table 1.

Example 3

The procedure of example 1 was followed except that the acid sludge sample to be tested (batch 3) was different. The interfacial tension of the KPS novel binary composite flooding is 4.9 multiplied by 10-3 mN/m, the viscosity of an oil displacement system can be increased after the KPS novel binary composite flooding is mixed with a polymer, and the oil displacement efficiency can reach more than 20 percent. The results are shown in FIG. 1, FIG. 2, table 1.

Table 1:

example 4

The only difference from example 1 is that the pH was changed to 8.

Example 5

The only difference from example 1 is that the pH was changed to 7.

Example 6

The only difference from example 1 is that the extractant for neutralizing the product was changed to acetone.

Example 7

The only difference from example 1 is that the heavy alkylbenzene is octadecylnaphthalene.

Example 8

The only difference from example 1 is that the azeotropically dehydrated toluene was changed to xylene.

Example 9

The only difference from example 1 is that the acid sludge to heavy alkylbenzene mass ratio is 3:4.

Example 10

The only difference from example 1 is that the acid sludge to heavy alkylbenzene mass ratio is 3:5.

Example 11

The only difference from example 1 is that the temperature at which the neutralized product is extracted is 60 ℃.

Example 12

The only difference from example 1 is that the extraction temperature of the neutralized acid sludge is 90 ℃.

Example 13

The only difference from example 1 is that the extraction temperature of the neutralized acid sludge is 95 ℃.

Example 14

The only difference from example 1 is that the crude product from step (6) is mixed with KPS in a mass ratio of 1:1.

Example 15

The only difference from example 1 is that the crude product from step (6) is mixed with KPS in a mass ratio of 1:5.

Example 16

The only difference from example 1 is that the crude product in step (6) is mixed with KPS in a mass ratio of 1.5.

And (3) detection:

the surfactants prepared in the above embodiments are all compounded with the polymer 1 to form a binary oil-displacing surfactant, the interfacial tension and the oil recovery rate of which are detected, and the detection results are shown in table 2.

Table 2:

example 17

The novel surfactant prepared in example 1 was mixed with 3 different polymers (polymer 2 was an AM/AHPE copolymer with ultra-high relative molecular mass of comb-shaped molecular structure, polymer 3 was a core-shell associative polymer HBPAM, polymer 4 was a sixteen-arm star-shaped polycaprolactone polymer, where the average molecular weight of the 3 polymers was 2500 ten thousand) to form a binary oil-displacing surfactant at a ratio of 0.5. And (4) detecting the performance of the formed binary oil-displacing surfactant according to SY/T6576-2016. The results of the measurements are shown in the following table.

Table 3:

the following conclusions were drawn from the above examples: after reasonable treatment, the acid sludge forms a novel surfactant which forms a binary oil displacement system with good oil displacement effect together with a polymer, and the interfacial tension of the binary oil displacement system can reach ultra-low (10) ^-3 mN/m), the recovery efficiency can be improved by more than 20.00 percent.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects: the method has the advantages that after acid sludge is treated, a surfactant crude product is obtained, and after the surfactant crude product is compounded with petroleum sulfonate, a novel surfactant with excellent interfacial activity and high oil displacement efficiency is successfully obtained.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A recycling method of acid sludge is characterized by comprising the following steps:

carrying out sulfonation reaction on the acid sludge and heavy alkylbenzene to obtain heavy alkylbenzene sulfonic acid;

neutralizing the heavy alkylbenzene sulfonic acid to obtain heavy alkylbenzene sulfonate;

mixing the heavy alkylbenzene sulfonate with KPS to obtain an oil displacement surfactant;

in the sulfonation reaction, the mass ratio of the acid sludge to the heavy alkylbenzene is 3 to 1-3;

the temperature of the sulfonation reaction is 70 to 80 ℃, and the reaction time is 6 to 8h;

neutralizing the heavy alkylbenzene sulfonic acid to obtain the heavy alkylbenzene sulfonate comprising:

adding alkali into the heavy alkyl benzene sulfonic acid to neutralize until the pH value is 8~9, and obtaining a neutralized product;

sequentially extracting and dehydrating the neutralized product to obtain the heavy alkylbenzene sulfonate;

and sequentially extracting the neutralized products by adopting any one of the following extracting agents: petroleum ether, diethyl ether, acetone, cyclohexane, ethyl acetate or hexane to obtain extract;

carrying out azeotropic dehydration on the extract by using any one of the following entrainers to obtain the heavy alkylbenzene sulfonate: toluene, xylene, isobutanol, chlorohydrin, pyridine or formic acid;

the extraction temperature of the extractant is 60 to 90 ℃;

the heavy alkylbenzene is a mixture of olefin and aromatic hydrocarbon structures obtained after oligomerization of propylene, and has a carbon chain branching structure, and the length of the carbon chain is more than 22 and less than 33;

after azeotropic dehydration and before obtaining the heavy alkylbenzene sulfonate, the recycling method further comprises:

extracting the product after azeotropic dehydration with ethanol, propanol, acetone or isopropanol;

mixing the heavy alkylbenzene sulfonate with KPS according to the mass ratio of 1 to 1.

2. An oil-displacing surfactant, characterized in that the oil-displacing surfactant is prepared by the recycling method of claim 1.

3. A binary oil-displacing surfactant, characterized in that the binary oil-displacing surfactant comprises a polymer and the oil-displacing surfactant prepared by the recycling method of claim 1.