An oil-based drill cuttings environmentally friendly treatment agent, its preparation method and application

Abstract

The present invention discloses an oil-based drill cuttings environmental protection treatment agent, a preparation method and application thereof, and belongs to the field of environmental protection treatment of petroleum drilling. The oil-based drill cuttings environmental protection treatment agent of the present invention comprises: 10 to 40 parts of n-hexane, 10 to 40 parts of cyclohexane, 10 to 40 parts of isohexane, 0 to 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone. The preparation method of the present invention comprises: preparing each raw material by volume, mixing them evenly, and obtaining the product. The method for desorbing organic pollutants from oil-containing drill cuttings by the oil-based drill cuttings environmental protection treatment agent of the present invention comprises: taking oil-based drill cuttings, adding the oil-based drill cuttings environmental protection treatment agent, leaching under stirring conditions, and then solid-liquid separation, drying the solid phase, and obtaining drill cuttings desorbed of organic pollutants. The oil-based drill cuttings environmental protection treatment agent of the present invention can be used for diesel-based drill cuttings and white oil-based oil-containing drill cuttings, has good safety, can effectively attach various organic pollutants on oil-containing drill cuttings, and has a high recovery rate.

Description

Technical Field

[0001] The invention belongs to the field of environmental protection treatment of petroleum drilling, and particularly relates to an oil-based drill cuttings environmental protection treatment agent, a preparation method and application thereof. Background Art

[0002] Oil-based drilling fluids are primarily composed of base oil, water, organic clay, and oil-soluble chemical treatment agents. The base oil is typically diesel or white oil. Oil-based muds are resistant to high temperatures and salt-calcium corrosion, contribute to wellbore stability, provide excellent lubricity, and minimize damage to oil and gas formations. They are widely used on various drilling platforms. The use of oil-based drilling fluids generates significant amounts of oily drill cuttings and waste during the drilling process. Both these wastes undergo a series of treatments to ensure they meet environmental standards before being discharged or recycled.

[0003] In the prior art, leaching agents are generally used to desorb oil-containing drill cuttings, separating the oil and other organic matter attached to the cuttings. For example, patent CN105969418A discloses a method for treating diesel-based drill cuttings using solvent extraction, specifically a method for treating shale gas diesel-based drilling fluid cuttings. The solvent used to treat shale gas diesel-based drill cuttings contains the following components, by weight: 20-40 parts n-hexane, 20-40 parts acetone, 20-40 parts methyl ethyl ketone, 10 parts ethyl acetate, and 10 parts ethanol. This solvent can achieve a crude oil recovery rate of approximately 99.7% for diesel-based drill cuttings. The optimal extraction conditions are: a solvent-to-mud ratio (volume ml: mass g) of 3:1, an extraction temperature of 45°C, a stirring speed of 500 rpm, an extraction time of 20 minutes, and a water-wash-three-stage cross-current extraction technique. After extraction, the recovery rate of the extractant can reach about 98.5%. The formulated extractant has the advantages of good effect, high recovery rate of crude oil, high recovery rate of the extractant itself, simple process, clean and pollution-free, and cost-saving. However, this leaching agent can only be used for diesel-based drilling fluid cuttings.

[0004] Patent CN108273843 A discloses a leaching agent for oil-containing drill cuttings and oil-containing drilling waste and its use method. The leaching agent comprises 80-100 parts by volume of polyoxymethylene dimethyl ether, 0-20 parts by volume of methyl tert-butyl ether, and 0-20 parts by volume of petroleum ether. The leaching agent is used as follows: the oil-containing drill cuttings and / or oil-containing drilling waste are mixed with the leaching agent in a blender; the mixture is stirred at a certain shear rate for a certain period of time to leach the oil-containing drill cuttings and / or oil-containing drilling waste; the mixture is allowed to stand for natural sedimentation of the solid phase, followed by solid-liquid separation and drying to obtain deoiled oil-containing drill cuttings and / or oil-containing drilling waste. Using this leaching agent, the treated solid phase contains ≤2.0% oil, and the recovery rate of the oil phase and separation system is ≥80%, providing technical support for the large-scale use of oil-based drilling fluids, as well as for environmental management and resource utilization. However, this leaching agent is only suitable for treating diesel-based oil-containing drill cuttings.

[0005] The applicant's prior application, CN113046111A, discloses a leaching agent for diesel-based and / or white oil-based oil-containing drill cuttings, as well as its preparation and use. The leaching agent comprises the following components by volume: 80-95 parts of a chlorinated hydrocarbon, 1-20 parts of isopropyl myristate, and 1-20 parts of a polysiloxane. The leaching agent is non-flammable, highly safe, and well-compatible. It effectively removes various organic pollutants from oil-containing drill cuttings and exhibits good biodegradability.

[0006] Oil-based drilling fluids and leaching agents have high economic value and are generally reused. However, a leaching agent that can simultaneously leached diesel-based and white oil-based oil-containing drill cuttings and effectively recycle them has not yet been reported. Therefore, providing a leaching agent that can be used for both diesel-based and white oil-based oil-containing drill cuttings and effectively recycle them has become an urgent problem for those skilled in the art. Summary of the Invention

[0007] One of the purposes of the present invention is to provide an environmentally friendly oil-based drill cuttings treatment agent that can be used for diesel-based drill cuttings and white oil-based oil-containing drill cuttings. It has good safety, can effectively remove various organic pollutants on the oil-containing drill cuttings, and has a high recovery rate.

[0008] The second object of the present invention is to provide a method for preparing the oil-based drill cuttings environmentally friendly treatment agent.

[0009] The third object of the present invention is to provide the application of the oil-based drill cuttings environmental protection treatment agent as an oil-based drill cuttings leaching agent.

[0010] A fourth object of the present invention is to provide a method for desorbing organic pollutants from oil-containing drill cuttings using the oil-based drill cuttings environmental treatment agent.

[0011] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0012] The present invention provides an oil-based drill cuttings environmental protection treatment agent, which comprises the following components in parts by volume: 10-40 parts of n-hexane, 10-40 parts of cyclohexane, 10-40 parts of isohexane, 0-20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0013] In some embodiments of the present invention, the following components are included in parts by volume: 25-30 parts of n-hexane, 25-30 parts of cyclohexane, 15-25 parts of isohexane, 10-20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0014] In some embodiments of the present invention, the following components are included in parts by volume: 30 parts of n-hexane, 30 parts of cyclohexane, 15 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0015] In some embodiments of the present invention, the following components are included in parts by volume: 25 parts of n-hexane, 25 parts of cyclohexane, 25 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0016] The preparation method of the oil-based drill cuttings environmental protection treatment agent provided by the present invention comprises the following steps:

[0017] Prepare the raw materials by volume and mix them evenly.

[0018] The oil-based drill cuttings environmental protection treatment agent provided by the present invention is used as an oil-based drill cuttings leaching agent.

[0019] In some embodiments of the present invention, the oil-based drill cuttings include diesel-based drill cuttings and / or white oil-based drill cuttings.

[0020] The method for desorbing organic pollutants from oil-containing drill cuttings using the oil-based drill cuttings environmental protection treatment agent provided by the present invention comprises the following steps:

[0021] Take oil-based drill cuttings, add oil-based drill cuttings environmental protection treatment agent, leaching under stirring conditions, and then separate the solid and liquid. After the solid phase is dried, the drill cuttings treated with organic pollutants are obtained;

[0022] Preferably, 2-8 parts by volume of an oil-based drill cuttings environmental protection treatment agent is added to 1 part by mass of oil drill cuttings for leaching;

[0023] Preferably, the leaching is carried out at room temperature;

[0024] Preferably, the leaching time is 0.5-8 hours.

[0025] Some embodiments of the present invention further include a step of recovering the oil-based drill cuttings environmental protection treatment agent.

[0026] In some embodiments of the present invention, the recovery step includes: sequentially distilling and stripping the liquid portion after solid-liquid separation, combining the distillation and stripping components, condensing, and separating the aqueous phase to obtain the recovered treatment agent.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The invention is scientifically designed and ingeniously conceived. The oil-based drill cuttings environmentally friendly treatment agent of the invention can be used for diesel-based drill cuttings and white oil-containing drill cuttings, has good safety, can effectively remove various organic pollutants on the oil-containing drill cuttings, and has a high recovery rate. DETAILED DESCRIPTION

[0029] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer are used. Where the manufacturer of the reagents or instruments is not specified, all are conventional products that can be purchased commercially.

[0030] An oil-based drill cuttings environmentally friendly treatment agent comprises the following components in parts by volume: 10-40 parts of n-hexane, 10-40 parts of cyclohexane, 10-40 parts of isohexane, 0-20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0031] Preferably, the oil-based drill cuttings environmental protection treatment agent comprises the following components in parts by volume: 25-30 parts of n-hexane, 25-30 parts of cyclohexane, 15-25 parts of isohexane, 10-20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0032] Preferably, the oil-based drill cuttings environmental protection treatment agent comprises the following components in parts by volume: 30 parts of n-hexane, 30 parts of cyclohexane, 15 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0033] Preferably, the oil-based drill cuttings environmental protection treatment agent comprises the following components in parts by volume: 25 parts of n-hexane, 25 parts of cyclohexane, 25 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0034] A method for preparing an oil-based drill cuttings environmentally friendly treatment agent comprises the following steps:

[0035] Prepare the raw materials by volume and mix them evenly.

[0036] Preferably, it is used as an oil-based drill cuttings leaching agent.

[0037] Preferably, the oil-based drill cuttings include diesel-based drill cuttings and / or white oil-based drill cuttings.

[0038] A method for desorbing organic pollutants from oil-containing drill cuttings using an oil-based drill cuttings environmental treatment agent comprises the following steps:

[0039] Take oil-based drill cuttings, add oil-based drill cuttings environmental protection treatment agent, leaching under stirring conditions, and then separate the solid and liquid. After the solid phase is dried, the drill cuttings treated with organic pollutants are obtained;

[0040] Preferably, 2-8 parts by volume of an oil-based drill cuttings environmental protection treatment agent is added to 1 part by mass of oil drill cuttings for leaching;

[0041] Preferably, the leaching is carried out at room temperature;

[0042] Preferably, the leaching time is 0.5-8 hours.

[0043] Preferably, the method further comprises a step of recovering the oil-based drill cuttings environmentally friendly treatment agent.

[0044] Preferably, the recovery step comprises: sequentially distilling and stripping the liquid portion after solid-liquid separation, combining the distillation and stripping components, condensing, and separating the aqueous phase to obtain the recovered treatment agent.

[0045] Unless otherwise specified, the parts described in the embodiments of the present invention are parts by volume.

[0046] Example 1

[0047] This embodiment discloses a method for preparing an oil-based drill cuttings environmental protection treatment agent of the present invention. In this embodiment, the raw material composition of the oil-based drill cuttings environmental protection treatment agent is:

[0048] 30 parts of n-hexane, 30 parts of cyclohexane, 15 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0049] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0050] Example 2

[0051] This embodiment discloses a method for preparing an oil-based drill cuttings environmental protection treatment agent of the present invention. In this embodiment, the raw material composition of the oil-based drill cuttings environmental protection treatment agent is:

[0052] 25 parts of n-hexane, 25 parts of cyclohexane, 25 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0053] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0054] Example 3

[0055] This embodiment discloses a method for preparing an oil-based drill cuttings environmental protection treatment agent of the present invention. In this embodiment, the raw material composition of the oil-based drill cuttings environmental protection treatment agent is:

[0056] 10 parts of n-hexane, 30 parts of cyclohexane, 10 parts of isohexane, 10 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0057] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0058] Example 4

[0059] This embodiment discloses a method for preparing an oil-based drill cuttings environmental protection treatment agent of the present invention. In this embodiment, the raw material composition of the oil-based drill cuttings environmental protection treatment agent is:

[0060] 30 parts of n-hexane, 40 parts of cyclohexane, 40 parts of isohexane, and 5 parts of N-methylpyrrolidone.

[0061] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0062] Example 5

[0063] This embodiment discloses a method for preparing an oil-based drill cuttings environmental protection treatment agent of the present invention. In this embodiment, the raw material composition of the oil-based drill cuttings environmental protection treatment agent is:

[0064] 40 parts of n-hexane, 10 parts of cyclohexane, 30 parts of isohexane, 10 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0065] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0066] Comparative Example 1

[0067] Compared with Example 1, this comparative example replaces all cyclohexane and isohexane with n-hexane, and its raw material composition is specifically as follows:

[0068] 75 parts of n-hexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0069] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0070] Comparative Example 2

[0071] Compared with Example 1, this comparative example replaces all isohexane with cyclohexane, and its raw material composition is specifically as follows:

[0072] 30 parts of n-hexane, 45 parts of cyclohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0073] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0074] Comparative Example 3

[0075] Compared with Example 1, this comparative example replaces all cyclohexane with isohexane, and its raw material composition is specifically as follows:

[0076] 30 parts of n-hexane, 45 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0077] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0078] Comparative Example 4

[0079] Compared with Example 1, this comparative example does not contain N-methylpyrrolidone, and its raw material composition is specifically as follows:

[0080] 30 parts of n-hexane, 30 parts of cyclohexane, 15 parts of isohexane, and 20 parts of polydimethylsiloxane.

[0081] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0082] Comparative Example 5

[0083] Compared with Example 1, the amount of polydimethylsiloxane used in this comparative example is 30 parts, and its raw material composition is specifically as follows:

[0084] 30 parts of n-hexane, 30 parts of cyclohexane, 15 parts of isohexane, 30 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

[0085] The preparation method is as follows: prepare various raw materials according to volume, mix them evenly, and then obtain the product.

[0086] Test Example 1

[0087] The oil-based drill cuttings environmental protection treatment agents of Examples 1-5 and Comparative Examples 1-5, and the leaching agent No. 1 in Example 1 of CN113046111A were used to investigate the deoiling effects on diesel-based oil-containing drill cuttings and white oil-based oil-containing drill cuttings. Specifically:

[0088] Take 1 part by mass of oil-containing drill cuttings, add 6 parts by volume of leaching agent, mix, and leaching at room temperature with low shear rate stirring at 500 rpm for 2 hours. After stirring and leaching, centrifuge to separate the solid and liquid phases, and dry the solid phase at 105°C to obtain deoiled oil-containing drill cuttings. When mass is expressed in g, volume is expressed in ml.

[0089] The liquid portion after solid-liquid separation is sequentially subjected to distillation and stripping under the same conditions, the distillation and stripping components are combined, condensed, and the aqueous phase is separated to obtain a recovered treatment agent.

[0090] The results are shown in the following table:

[0091] Table 1

[0092]

[0093] As can be seen from the above table, the oil-based drill cuttings environmentally friendly treatment agent of the present invention has a good deoiling effect not only on diesel-based oil-containing drill cuttings, but also on white oil-based oil-containing drill cuttings; and the recovery rate of the leaching agent is high.

[0094] Although the leaching agent of CN113046111A has a good deoiling effect on both diesel-based oil-containing drill cuttings and white oil-based oil-containing drill cuttings, the recovery rate of the leaching agent is not high.

[0095] The oil-based drill cuttings environmentally friendly treatment agents of Comparative Examples 1 to 5 have lower deoiling effects on diesel-based oil-containing drill cuttings and white oil-based oil-containing drill cuttings than the present invention, and the recovery rate of the leaching agent is not high.

[0096] Test Example 2

[0097] This test example used the environmentally friendly oil-based drill cuttings treatment agent from Example 1 to investigate the conditions for desorbing organic pollutants from oil-containing drill cuttings. The specific method involved adding varying volumes of the leaching agent to one part of the oil-containing drill cuttings, mixing, and stirring at a low shear rate of 500 rpm at room temperature for leaching. After the stirring leaching, the solid and liquid phases were separated by centrifugation, and the solid phase was dried at 105°C to obtain the deoiled oil-containing drill cuttings. Where mass is expressed in g, volume is expressed in ml.

[0098] Table 2

[0099]

[0100] It can be seen from the above table that when the immersion time increases from 0.5 to 8 hours, the oil removal rate increases, but after more than 8 hours, the oil removal rate no longer increases with time.

[0101] When the amount of the leaching agent is 2-8 parts by volume, the oil removal rate increases with the increase of the amount of the leaching agent. However, when the amount of the leaching agent is greater than 8 parts by volume, the oil removal rate no longer increases with the increase of the amount of the leaching agent.

[0102] Finally, it should be noted that the above embodiments are merely preferred embodiments of the present invention and are intended to illustrate the technical solutions of the present invention, not to limit the present invention, and certainly not to limit the scope of the present invention. Any modifications or improvements that are insubstantial to the main design concept and spirit of the present invention, provided that the technical problems they solve are consistent with the present invention, shall be included within the scope of protection of the present invention. Furthermore, any direct or indirect application of the technical solutions of the present invention to other related technical fields shall also be included within the scope of protection of the present invention.

Claims

1. An application of an oil-based drill cuttings environmental protection treatment agent, characterized in that: The oil-based drill cuttings environmental protection treatment agent is used as an oil-based drill cuttings leaching agent, and the oil-based drill cuttings environmental protection treatment agent is composed of the following components in parts by volume: 10-40 parts of n-hexane, 10-40 parts of cyclohexane, 10-40 parts of isohexane, 10-20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

2. The use of an oil-based drill cuttings environmental treatment agent according to claim 1, characterized in that: The oil-based drill cuttings environmental protection treatment agent is composed of the following components in parts by volume: 25-30 parts of n-hexane, 25-30 parts of cyclohexane, 15-25 parts of isohexane, 10-20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

3. The use of an oil-based drill cuttings environmental treatment agent according to claim 1 or 2, characterized in that: The oil-based drill cuttings environmental protection treatment agent is composed of the following components in parts by volume: 30 parts of n-hexane, 30 parts of cyclohexane, 15 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

4. The use of an oil-based drill cuttings environmental treatment agent according to claim 1 or 2, characterized in that: The oil-based drill cuttings environmental protection treatment agent is composed of the following components in parts by volume: 25 parts of n-hexane, 25 parts of cyclohexane, 25 parts of isohexane, 20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone.

5. The use of an oil-based drill cuttings environmental treatment agent according to claim 1, characterized in that: The oil-based drill cuttings include diesel-based drill cuttings and / or white oil-based drill cuttings.

6. A method for desorbing organic pollutants from oil-based drill cuttings using an oil-based drill cuttings environmental treatment agent, characterized in that: The oil-based drill cuttings environmental protection treatment agent is composed of the following components by volume: 10-40 parts of n-hexane, 10-40 parts of cyclohexane, 10-40 parts of isohexane, 10-20 parts of polydimethylsiloxane, and 5 parts of N-methylpyrrolidone. The method comprises the following steps: taking oil-based drill cuttings, adding the oil-based drill cuttings environmental protection treatment agent, leaching at room temperature with stirring, then separating the solid and liquid, and drying the solid phase to obtain drill cuttings free of organic pollutants; and adding 2-8 ml of the oil-based drill cuttings environmental protection treatment agent to 1 gram of the oil-based drill cuttings.

7. The method for desorbing organic pollutants from oil-based drill cuttings using an environmentally friendly oil-based drill cuttings treatment agent according to claim 6, characterized in that: The leaching time is 0.5-8 hours.

8. The method for desorbing organic pollutants from oil-based drill cuttings using an environmentally friendly oil-based drill cuttings treatment agent according to claim 6, characterized in that: The method also includes a step of recycling an oil-based drill cuttings environmentally friendly treatment agent.

Images