Clamping freeing agent, ultrahigh-density clamping freeing liquid, preparation method and application

Abstract

The invention provides an unfreezing agent, an ultra-high-density unfreezing solution and a preparation method and application thereof. The preparation method of the stuck freeing agent comprises the step of uniformly mixing the polyglycerol fatty acid ester, the stearic acid monoethanolamide, the isooctyl alcohol polyoxyethylene ether monophosphate and the hydrophilic polysaccharide alcohol according to the mass ratio of (1-3): (1-2): (10-11): (5-7) to obtain the stuck freeing agent. The preparation method of the jam freeing liquid comprises the following steps: sequentially adding calcium chloride and potassium chloride into water, and uniformly stirring to obtain a saline water phase; adding the jam freeing agent into the oil phase, and uniformly stirring to obtain an intermediate product; uniformly mixing the salt water phase and the intermediate product to obtain a water-in-oil emulsion; and adding a viscosity reducer and barite into the water-in-oil emulsion, and uniformly stirring to obtain the jam freeing liquid. The application comprises the application in drilling jam releasing operation. The prepared jam freeing liquid is simple in preparation process, high in jam freeing efficiency, high in settling stability and high in market popularization value.

Description

Technical Field

[0001] This invention relates to the field of oilfield drilling fluid technology, specifically to unblocking agents, ultra-high density unblocking fluids, their preparation methods, and applications. Background Technology

[0002] Stuck pipe is a common drilling accident, and improper handling can often lead to huge economic losses in drilling operations. Differential pressure stuck pipe is the most frequent and causes the greatest damage. Currently, methods for resolving differential pressure stuck pipe accidents are generally divided into mechanical / physical methods and chemical methods. Mechanical / physical methods typically employ techniques such as shock and explosive milling; the disadvantages of this method are its long processing time and high operating costs. Among chemical methods, acid soaking has a high success rate, but it is only suitable for wellbore stability and inactive oil and gas shows. In most cases, the soaking solution method within the chemical treatment approach is used.

[0003] The basic principle of chemical unsticking is to disrupt the internal structure of the drilling mud and enhance its lubrication, thereby transmitting pressure to the stuck interface. This weakens the adhesion and viscous forces between the drill string and the mud, disrupting the drill string-mud-cake force system and allowing the drill string to be released. In recent years, many types of unsticking fluids have been developed, including water-based, oil-based, and oil-in-water types. However, each of these unsticking fluids has its advantages and disadvantages, and all have certain limitations.

[0004] In the Bozi, Dabei, and Keping blocks of the Tarim Basin, there are situations with high formation pressure and extremely high drilling fluid density, especially in the Keping structure, where the highest actual drilling density reaches 2.58 g / cm³. 3 Due to its ultra-high density, the formation pressure coefficient varies significantly, making differential pressure sticking more likely during actual drilling. When sticking occurs, to balance formation pressure and ensure downhole safety, ultra-high density (≥2.3 g / cm³) is required. 3 (Under certain conditions, there is also a card-unlocking fluid with outstanding card-unlocking efficiency.) Summary of the Invention

[0005] The purpose of this invention is to address at least one of the aforementioned deficiencies in the prior art. For example, one objective of this invention is to provide a method for preparing a card unlocking agent; a second objective of this invention is to provide a card unlocking agent; a third objective of this invention is to provide a method for preparing an ultra-high density card unlocking solution; a fourth objective of this invention is to provide an ultra-high density card unlocking solution; and a fifth objective of this invention is to provide applications of the ultra-high density card unlocking solution.

[0006] To achieve the above objectives, the first aspect of the present invention provides a method for preparing an anti-card agent.

[0007] The method can comprise: uniformly mixing polyglyceryl fatty acid ester, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate and hydrophilic polysaccharide alcohol in a mass ratio of (1-3):(1-2):(10-11):(5-7) to obtain the de-caking agent.

[0008] Alternatively, the polyglyceryl fatty acid ester can comprise one or more of polyglyceryl-4 isostearate, tri-polyglyceryl di-oleate and polyglyceryl-3 di-isostearate.

[0009] Alternatively, the hydrophilic polysaccharide alcohol can comprise one or both of xylitol and sorbitol.

[0010] Alternatively, the uniform mixing can comprise: adding polyglyceryl fatty acid ester, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate and hydrophilic polysaccharide alcohol in a reaction kettle, performing first stirring; then heating and performing second stirring, stopping heating after uniform mixing, continuing stirring, and stopping stirring when the temperature is below 40℃.

[0011] Alternatively, the first stirring time can be 25-35 min; the second stirring time can be 40-1.5 h; and the heating temperature can be 50-80℃.

[0012] Alternatively, the stirring is electric stirring, and the stirring rate can be 50-60 r / min. Further, the motor power of the stirring can be 15 KW.

[0013] The second aspect of the application provides a de-caking agent.

[0014] The de-caking agent can be prepared by the method of the first aspect.

[0015] The third aspect of the application provides a preparation method of an ultra-high density de-caking liquid.

[0016] The method can comprise: adding calcium chloride and potassium chloride into water in sequence, stirring uniformly to obtain a brine phase; adding the de-caking agent prepared in the application into an oil phase, stirring uniformly to obtain an intermediate product; uniformly mixing the brine phase and the intermediate product to obtain a water-in-oil emulsion; adding a viscosity reducer and barite into the water-in-oil emulsion, stirring uniformly to obtain the de-caking liquid.

[0017] Alternatively, the mass ratio of the oil phase, the viscosity reducer, the water, the calcium chloride, the potassium chloride and the de-caking agent can be (70-95):(3-5):(5-30):(1-3):(0.5-2):(30-50).

[0018] Alternatively, the amount of the barite can be determined according to the density.

[0019] Optionally, the oil phase can include diesel oil or white oil.

[0020] Optionally, the viscosity reducer can include a polyamide compound.

[0021] Optionally, the stirring can be electric stirring. The stirring rate can be 50-60 r / min. Further, the motor power of the stirring can be 15 KW.

[0022] The fourth aspect of the present application provides a super-high density releasing agent.

[0023] The super-high density releasing agent can be prepared by the method of the third aspect described above.

[0024] The fifth aspect of the present application provides the application of the super-high density releasing agent.

[0025] The application can include that the releasing agent or the super-high density releasing agent can be applied in the releasing operation of drilling.

[0026] Compared with the prior art, the beneficial effects of the present application include at least one of the following:

[0027] (1) The present application adopts the "multi-salt water composite adjustment technology" and the "self-emulsifying technology", uses "calcium chloride + potassium chloride + hydrophilic polysaccharide alcohol" as the inner phase in the water phase, greatly reduces the activity of the inner phase, increases the osmotic pressure of the emulsion, and further promotes the penetration of the oil phase, thereby greatly improving the releasing efficiency.

[0028] (2) The present application adopts the multifunctional surfactant stearic acid monoethanolamide, which can be compounded with polyglycerol fatty acid ester to form a self-emulsifying surfactant, thereby improving the anti-settling effect of the system, reducing the use of organic soil and other lipophilic micro-nano colloidal particles, and avoiding the deposition and plugging of the oil phase penetration channel by organic soil and asphalt.

[0029] (3) The present application adopts a self-produced viscosity reducer, which reduces the viscosity and shear force of the high-density releasing agent, cooperates with stearic acid monoethanolamide, increases the dispersion of barite, improves the anti-settling effect of barite, and greatly improves the sedimentation stability of the releasing agent system.

[0030] (4) The releasing agent formed by compounding the self-emulsifying surfactant and the penetrant in the present application has simple formula, wide raw material sources, and low cost. The introduction of the self-emulsifying process greatly improves the emulsification efficiency, meets the actual situation of low shear action of the circulating tank in the field construction, and has strong market promotion value.

[0031] (5) The present application constructs a super-high density releasing agent system based on the releasing agent, which has the advantages of high density (2.3 g / cm3-2.6 g / cm3), outstanding releasing efficiency, and simple preparation process. Attached Figure Description

[0032] The above and other objects and / or features of the present invention will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0033] Figure 1 The preparation of 2.6 g / cm³ of conventional card release agent and the card release agent of the present invention (Example 1) is shown. 3 Comparison of the effects of anti-card solution on soaking mud cakes. Detailed Implementation

[0034] In the following sections, the unblocking agent, ultra-high density unblocking solution, preparation method, and application of the present invention will be described in detail with reference to exemplary embodiments.

[0035] Exemplary Example 1

[0036] This exemplary embodiment provides a method for preparing an unblocking agent.

[0037] The preparation method may include the following steps:

[0038] The unblocking agent is obtained by uniformly mixing polyglycerol fatty acid ester, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and hydrophilic polysaccharide alcohol in a mass ratio of A1:A2:A3:A4. Wherein, A1 = 1–3, for example 1.1, 1.5, 1.7, 1.9, 2, 2.5, 2.9, etc.; A2 = 1–2, for example 1.1, 1.5, 1.7, 1.9, etc.; A3 = 10–11, for example 10.1, 10.5, 10.8, 10.9, etc.; A4 = 5–7, for example 5.1, 5.5, 6, 6.5, 6.9, etc.

[0039] In this embodiment, the polyglycerol fatty acid ester may include one or more of polyglycerol-4 isostearate, polyglycerol dioleate, and polyglycerol-3 diisostearate.

[0040] The purpose of selecting polyglycerol fatty acid esters as the main self-emulsifying water-in-oil emulsifier is that they have outstanding wettability, dispersibility, emulsifying ability, low dynamic surface tension, and are completely biodegradable.

[0041] Stearic acid monoethanolamide was chosen as the main emulsifier, which can synergistically emulsify the free water in the mud cake with polyglycerol fatty acid esters; at the same time, stearic acid monoethanolamide also has the functions of dispersing, oil wetting and thickening, and can play a role in preventing barite from settling in the system.

[0042] The reason for choosing isooctanol polyoxyethylene ether monophosphate as a penetrant is that it is an alkali-resistant and fast penetrant, which can effectively avoid the failure of conventional penetrants when they come into contact with alkaline drilling fluids.

[0043] The hydrophilic polysaccharide alcohol includes one or both of xylitol and sorbitol.

[0044] Among them, hydrophilic polysaccharide alcohol plays a role in regulating the osmotic pressure of the emulsion in the aqueous phase. It can increase the osmotic pressure of the emulsion, thereby causing free water in the mud cake to move directionally to the aqueous phase of the emulsion, resulting in dehydration.

[0045] In this embodiment, the uniform mixing may include:

[0046] Polyglycerol fatty acid ester, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate and hydrophilic polysaccharide alcohol were added sequentially to the reaction vessel and stirred for the first time.

[0047] Then heat and stir a second time. Once the mixture is homogeneous, stop heating and continue stirring until the temperature drops below 40°C.

[0048] The first stirring time is 25 min to 35 min, such as 25 min, 26 min, 29 min, 30 min, 31 min and 35 min, etc., the purpose of which is to initially mix the raw materials evenly.

[0049] The second stirring time is 40 min to 1.5 h, such as 40 min, 41 min, 46 min, 50 min, 55 min, 1 h, 1.1 h and 1.5 h, etc.; the heating temperature is 50℃ to 80℃, such as 50℃, 51℃, 56℃, 60℃, 65℃, 72℃ and 80℃, etc.

[0050] The purpose of heating at 50–80°C is to promote the dissolution of the solid while reducing the risk.

[0051] In this embodiment, the stirring is an electric stirring machine with a motor power of 15KW and a stirring speed of 50-60r / min.

[0052] Exemplary Example 2

[0053] This exemplary embodiment provides a card unblocking agent.

[0054] The unblocking agent is obtained by mixing the raw materials shown in Table 1, by mass parts.

[0055] Table 1 Formulation of the Unblocking Agent of the Present Invention

[0056] Ingredients Proportion Polyglyceryl fatty acid ester 10-30 parts Stearic acid monoethanolamide 10-20 parts Isoceteth-20 100-110 parts Hydrophilic polysaccharide alcohol 50-70 parts

[0057] The functions of each raw material component in this invention are as follows:

[0058] Polyglycerol fatty acid esters: Commercially available, used as the main agent in self-emulsifying water-in-oil emulsifiers. They exhibit outstanding wetting, dispersing, and emulsifying properties, low dynamic surface tension, and are completely biodegradable. Further, polyglycerol fatty acid esters include one or more of polyglycerol-4 isostearate, polyglycerol dioleate, and polyglycerol-3 diisostearate.

[0059] Stearic acid monoethanolamide: Primarily used as an emulsifier. Synergistically with polyglycerol fatty acid esters, it emulsifies free water in the mud cake. Stearic acid monoethanolamide also has dispersing, oil-wetting, and thickening effects. It can prevent barite sedimentation in the system.

[0060] Isooctyl alcohol polyoxyethylene ether monophosphate: commercially available, CAS 68439-39-4, an alkali-resistant fast penetrant that effectively prevents conventional penetrants from failing when exposed to alkaline drilling fluids.

[0061] Hydrophilic polysaccharide alcohols: In the aqueous phase, they play a role in regulating the osmotic pressure of the emulsion, increasing the osmotic pressure of the emulsion, thereby causing free water in the cake to move directionally to the aqueous phase of the emulsion, thus resulting in dehydration. Further, hydrophilic polysaccharide alcohols include one or both of xylitol and sorbitol.

[0062] In this embodiment, the preparation method of the card unblocking agent includes:

[0063] (1) Add polyglycerol fatty acid ester, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate and hydrophilic polysaccharide alcohol in sequence in proportion to the reaction vessel and stir continuously (e.g., for 30 min).

[0064] (2) Heat to a certain temperature (e.g., 60°C) and stir (e.g., for 1 hour). After the sample is uniform, stop heating and continue stirring. When the temperature drops below 40°C, stop stirring and discharge the material, which is the unblocking agent of the present invention.

[0065] Exemplary Example 3

[0066] This exemplary embodiment provides a card unblocking agent.

[0067] The unblocking agent can be prepared by the method described in Exemplary Example 1 or 2.

[0068] Exemplary Example 4

[0069] This embodiment provides a method for preparing an ultra-high density card unlocking solution.

[0070] The method may include the following steps:

[0071] Add calcium chloride and potassium chloride to water in sequence, stir well, and a brine phase is obtained;

[0072] Add the unblocking agent described in Exemplary Example 2 to the oil phase, stir until homogeneous, and obtain an intermediate product;

[0073] The brine phase and intermediate product were mixed evenly to obtain a water-in-oil emulsion;

[0074] Add a viscosity reducer and barite to the water-in-oil emulsion and stir until homogeneous to obtain the unblocking solution.

[0075] In this embodiment, the mass ratio of the oil phase, viscosity reducer, water, calcium chloride, potassium chloride, and unblocking agent can be B1:B2:B3:B4:B5:B6. Wherein, B1 = 70–95, for example, 70, 72, 79, 80, 83, 90, 94, etc.; B2 = 3–5, for example, 3.1, 3.4, 3.6, 4, 4.3, 4.9, etc.; B3 = 5–30, for example, 5, 7, 10, 19, 23, 26, 29, etc.; B4 = 1–3, for example, 1.1, 1.6, 1.9, 2, 2.2, 2.9, etc.; B5 = 0.5–2, for example, 0.5, 0.8, 1.1, 1.4, 1.9, etc.; and B6 = 30–50, for example, 31, 34, 37, 40, 44, 49, etc.

[0076] In this embodiment, the purpose of adding calcium chloride and potassium chloride is to provide calcium and potassium ions in the drilling fluid, thereby increasing the mineralization.

[0077] The purpose of adding calcium chloride and potassium chloride in sequence is to add calcium chloride first, so that the exothermic effect of calcium chloride can be used to promote the dissolution of potassium chloride.

[0078] In this embodiment, the density of the barite can be 4.35 g / cm³. 3 The purpose is to act as a density regulator, and the amount used is determined according to the required density.

[0079] In this embodiment, the oil phase may include diesel or white oil. The purpose of the oil phase is to provide a lubricating oil phase that, with the help of a penetrant, quickly enters the space between the tubing and the mud cake or well wall, achieving a good lubricating effect and reducing the rubbing force between the drill string and the mud cake.

[0080] In this embodiment, the viscosity reducer may include a polyamide compound. The addition of the viscosity reducer mainly serves to reduce the viscosity of the unblocking solution, adjust the rheology of the unblocking solution, and help improve the sedimentation stability of the unblocking solution.

[0081] In this embodiment, all stirring is done by electric stirring, with a motor power of 15KW and a stirring speed of 50-60r / min.

[0082] Exemplary Example 5

[0083] This exemplary embodiment provides an ultra-high density card unlocking fluid.

[0084] The ultra-high density card-unlocking solution is prepared from the raw materials shown in Table 2, by weight. The card-unlocking agent is the card-unlocking agent described in Exemplary Example 2 or 3.

[0085] Table 2 Formula of the Card Unblocking Solution of the Present Invention

[0086]

[0087]

[0088] The amount of barite added is adjusted according to density requirements, with the maximum density adjustable to 2.60 g / cm³. 3 .

[0089] 0# diesel or 3# white oil: provides the oil phase, has a lubricating effect, and can quickly enter the tubing and mud cake or well wall with the help of penetrant, so as to achieve a good lubrication effect and reduce the friction between the drill string and the mud cake.

[0090] CQ-OTA (Polyamide Compound for Viscosity Reducing in Oil-Based Drilling Fluids): Produced by China Petroleum Sichuan Drilling Engineering Co., Ltd., it mainly reduces the viscosity of the unsticking fluid, adjusts the rheological properties of the unsticking fluid, and helps improve the settling stability of the unsticking fluid.

[0091] In this embodiment, the preparation method of the card unlocking solution may include:

[0092] (1) Add clean water to drilling fluid tank 1#, and while stirring, add calcium chloride and potassium chloride in sequence, and continue stirring (for example, for 45 minutes) to form a brine phase.

[0093] (2) Add diesel (or white oil) and a certain amount of unblocking agent to drilling fluid tank 2#, stir (for example, for 20 minutes), and use an air diaphragm pump to pump the salt in tank 1# into tank 2# while stirring continuously (for example, for 1 hour). At the same time, turn on the weight pump to circulate and shear to form an oil-in-water emulsion.

[0094] (3) Turn on the weight pump to circulate the emulsion in tank #2. While adding barite, add viscosity reducer (CQ-OTA) to tank #2. After the required density is reached, continue stirring (e.g., for 1 hour) to obtain the required unblocking solution.

[0095] Furthermore, the stirring process in the preparation method is carried out by electric stirring, with a motor power of 15KW and a stirring speed of 50-60rpm.

[0096] Exemplary Example 6

[0097] This exemplary embodiment provides an ultra-high density card unlocking fluid.

[0098] The card-unblocking solution is prepared by the method described in Exemplary Example 4 or 5 above.

[0099] Exemplary Example 7

[0100] This exemplary embodiment provides the application of card release agents or ultra-high density card release solutions.

[0101] The application may include use in drilling unsticking operations.

[0102] To better understand the exemplary embodiments described above, further explanation is provided below with specific examples.

[0103] Example 1 (standard formulation, diesel fuel, density 2.3, emulsifier 1)

[0104] In a reactor, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 20:15:105:60, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0105] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.3 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0106] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 50rpm.

[0107] Example 2 (standard formulation, diesel fuel, density 2.3, polyglycerol fatty acid ester 2)

[0108] In a reaction vessel, triglyceride dioleate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:65, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0109] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.3 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0110] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 60rpm.

[0111] Example 3 (Emulsifier 3, density 2.3)

[0112] In a reaction vessel, polyglycerol-3 diisostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 12:23:105:67, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0113] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.3 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0114] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 55rpm.

[0115] Example 4 (white oil, density 2.3)

[0116] In a reaction vessel, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:55, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0117] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 70 parts of No. 3 white oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.3 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0118] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 60rpm.

[0119] Example 5 (Polysaccharide alcohol 2, density 2.3)

[0120] In a reactor, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:65, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, the heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, the stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0121] In drilling fluid tank #1, add 30 parts by weight of clean water. While stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride sequentially, and continue stirring for 45 minutes to form a brine phase. In drilling fluid tank #2, add 70 parts of #0 diesel oil and 35 parts of unblocking agent, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. Simultaneously, start the weight pump for circulation shearing. Start the weight pump to circulate the emulsion in tank #2. While adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2, and weight it to a density of 2.3 g / cm³. 3 Then, continue stirring for 1 hour to obtain the desired solution.

[0122] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 50rpm.

[0123] Example 6 (diesel, density 2.4)

[0124] In a reaction vessel, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:55, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0125] Add 20 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 2 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 80 parts of #0 diesel oil and 40 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 4 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.4 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0126] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 50rpm.

[0127] Example 7 (diesel, density 2.5)

[0128] In a reactor, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:50, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, the heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, the stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0129] In drilling fluid tank #1, add 10 parts by weight of clean water. While stirring, add 2 parts of calcium chloride and 1 part of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. In drilling fluid tank #2, add 90 parts of #0 diesel oil and 45 parts of unblocking agent, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2. While adding barite, add 5 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.5 g / cm3, continue stirring for 1 hour to obtain the desired unblocking solution.

[0130] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 60rpm.

[0131] Example 8 (diesel, density 2.6)

[0132] In a reactor, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:50, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, the heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, the stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0133] Add 5 parts by weight of water to drilling fluid tank #1, and while stirring, add 1 part of calcium chloride and 0.5 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 95 parts of #0 diesel oil and 50 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 6 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.6 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0134] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 55rpm.

[0135] Comparative Example 1 (The adhesive ingredient does not contain polysaccharide alcohol)

[0136] In a reactor, 15 parts of polyglycerol-4 isostearate, 20 parts of stearic acid monoethanolamide, and 105 parts of isooctanol polyoxyethylene ether monophosphate were added sequentially in a mass ratio of 15:20:105, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, the heating was stopped, and the stirring was continued until the temperature dropped to 40°C. The mixture was then discharged to obtain the unblocking agent.

[0137] In drilling fluid tank #1, add 30 parts by weight of clean water. While stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride sequentially, and continue stirring for 45 minutes to form a brine phase. In drilling fluid tank #2, add 70 parts of #0 diesel oil and 35 parts of unblocking agent, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. Simultaneously, start the weight pump for circulation shearing. Start the weight pump to circulate the emulsion in tank #2. While adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2, and weight it to a density of 2.3 g / cm³. 3 Then, continue stirring for 1 hour to obtain the desired solution.

[0138] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 50rpm.

[0139] Comparative Example 2 (The solution used to remove the card contained only calcium chloride)

[0140] In a reactor, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:60, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, the heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, the stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0141] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. While adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2, and add weight until the density is 2.3 g / cm3. Continue stirring for 1 hour to obtain the desired unblocking solution.

[0142] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 60rpm.

[0143] Comparative Example 3 (The unblocking agent and emulsifier were replaced with SP-80)

[0144] SP-80, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially to a reactor at a mass ratio of 35:105:60, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, the heating was stopped, and the stirring was continued until the temperature dropped to 40°C. Then the stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0145] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.3 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0146] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 55rpm.

[0147] Comparative Example 4 (The only unblocking agent was stearic acid monoethanolamide)

[0148] Stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially to a reaction vessel at a mass ratio of 115:20:65, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogeneous, the heating was stopped, and the stirring was continued until the temperature dropped to 40°C. Then, the stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0149] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion in tank #2, and while adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2. After adding weight to a density of 2.3 g / cm3, continue stirring for 1 hour to obtain the required unblocking solution.

[0150] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 50rpm.

[0151] Comparative Example 5 (The solution used to unblock the card contained only potassium chloride)

[0152] In a reaction vessel, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:65, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0153] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 2 parts of potassium chloride and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. While adding barite, add 3 parts of viscosity reducer (CQ-OTA) to tank #2, and add weight until the density is 2.3 g / cm3. Continue stirring for 1 hour to obtain the desired unblocking solution.

[0154] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 60rpm.

[0155] Comparative Example 6 (Unblocking solution without viscosity reducer)

[0156] In a reaction vessel, polyglycerol-4 isostearate, stearic acid monoethanolamide, isooctanol polyoxyethylene ether monophosphate, and xylitol were added sequentially in a mass ratio of 15:20:105:60, and the mixture was stirred continuously for 30 minutes. The mixture was heated to 60°C and stirred for 1 hour. After the sample was homogenized, heating was stopped, and stirring was continued until the temperature dropped to 40°C. Then, stirring was stopped, and the mixture was discharged to obtain the unblocking agent.

[0157] Add 30 parts by weight of clean water to drilling fluid tank #1, and while stirring, add 3 parts of calcium chloride and 2 parts of potassium chloride in sequence, and continue stirring for 45 minutes to form a brine phase. Add 70 parts of #0 diesel oil and 35 parts of unblocking agent to drilling fluid tank #2, and stir for 20 minutes. While stirring, use an air diaphragm pump to pump the salt from tank #1 into tank #2, and continue stirring for 1 hour. At the same time, start the weight pump to circulate and shear the emulsion in tank #2. Start the weight pump to circulate the emulsion, add barite, and add weight until the density is 2.3 g / cm3. Continue stirring for 1 hour to obtain the required unblocking solution.

[0158] The stirring process is carried out using electric stirring, with a motor power of 15KW and a stirring speed of 55rpm.

[0159] Comparative Examples 7-8 are unlocking solutions formulated with commercially available unlocking agents.

[0160] Experimental Example

[0161] 1. Rheological properties and stability (demulsification voltage, sedimentation stability) evaluation

[0162] Following the preparation methods of the above embodiments and comparative examples, the prepared unblocking fluid was stirred at high speed for 1 hour, heated to 40°C, and its rheological properties were measured according to the method specified in GB / T 16783.1-2014 Petroleum and Natural Gas Industry Drilling Fluid Field Testing Part 1: Water-based Drilling Fluids. After the test, the unblocking fluid was transferred to an aging vessel and kept at a constant temperature of 100°C for 10 hours. Then, it was taken out and the density difference and electrical stability were measured. The electrical stability test method was carried out according to the method specified in GB / T 16783.1-2014 Petroleum and Natural Gas Industry Drilling Fluid Field Testing Part 2: Oil-based Drilling Fluids.

[0163] 2. Card unlocking performance evaluation

[0164] Prepare the corresponding unsticking fluid according to the methods of the examples and comparative examples. Take the prepared unsticking fluid and determine the unsticking time according to the evaluation procedure for unsticking agents for drilling fluids in SY / T6093-94.

[0165] 3. Analysis of on-site application effects

[0166] Results Discussion

[0167] 1. Indoor evaluation effect

[0168] Table 3 Comparison of drilling fluid performance between examples and comparative examples

[0169]

[0170] The effects of rheological demulsification voltage, density difference, and indoor card release time in different embodiments and comparative examples show that the card release agent and card release solution prepared in the embodiments of the present invention can be analyzed as follows:

[0171] (1) From Example 1-Example 2 and Comparative Example 7-Comparative Example 8 and Appendix Figure 1 It can be seen that the card-unlocking solution formulated with the card-unlocking agent of this invention has a much better card-unlocking effect than the card-unlocking solution formulated with commercially available card-unlocking agents, demonstrating the outstanding card-unlocking efficiency, emulsification stability, and better sedimentation stability and rheological properties of the product of this invention.

[0172] (2) As can be seen from the comparison between Examples 1-3 and Example 4, the unblocking agent of the present invention is applicable not only to diesel-based systems but also to white oil-based systems.

[0173] (3) As can be seen from the comparison of Examples 1 and 6-8, and the comparison with Comparative Examples 7 and 8, the highest density of the card-unlocking agent and card-unlocking liquid system of the present invention can reach 2.6 g / cm³. 3 Even under ultra-high density conditions, it still exhibits outstanding card-unblocking efficiency.

[0174] (4) As can be seen from the comparison between Example 1 and Comparative Example 1, the addition of hydrophilic polysaccharide alcohol helps to improve the de-carding efficiency of the de-carding solution system. The analysis is that the hydrophilic polysaccharide alcohol in the de-carding agent dissolves into the aqueous phase during emulsification, which increases the osmotic pressure of the emulsion, thereby making it easier for free water in the mud cake to enter the inner phase and dehydrate during de-carding.

[0175] (5) The comparison between Example 1 and Comparative Examples 2 and 5 shows that the deactivation effect of using calcium chloride or potassium chloride alone as the internal phase salt is not as good as that of using both in combination. This indicates that the combined use of calcium chloride and potassium chloride not only reduces the internal phase activity, but also has a synergistic effect.

[0176] (6) Comparisons of Examples 1-3 and Comparative Examples 3 and 4 show that the unblocking agent formulated with polyglycerol fatty acid ester and stearic acid monoethanolamide has a synergistic effect on improving the unblocking efficiency, which is significantly better than conventional emulsifiers (SP-80). Furthermore, the density difference between the upper and lower layers indicates that polyglycerol fatty acid ester and stearic acid monoethanolamide help disperse barite in the system, thus improving the sedimentation stability of the entire system. The demulsification voltage shows that the emulsifier used in the examples has a significantly higher emulsification efficiency than the conventional SP-80.

[0177] (7) As can be seen from the comparison between Example 1 and Comparative Example 6, the addition of viscosity reducer can significantly reduce the viscosity of the system, resulting in better rheological properties of the entire example unblocking fluid system, which is more conducive to slurry pumping. At the same time, the density difference between the upper and lower parts shows that the addition of viscosity reducer also significantly helps to improve the settling stability of the entire example unblocking fluid.

[0178] 2. On-site application effect

[0179] Table 4 Example 1: Field application effects of the card release agent and the card release solution prepared with the agent.

[0180]

[0181]

[0182] Although the present invention has been described above in conjunction with exemplary embodiments and accompanying drawings, those skilled in the art should understand that various modifications can be made to the above embodiments without departing from the spirit and scope of the claims.

Claims

1. A method for preparing a card unlocking agent, characterized in that, The preparation method includes: The unblocking agent is obtained by mixing polyglycerol fatty acid ester, stearic acid monoethanolamide, isooctyl alcohol polyoxyethylene ether monophosphate and hydrophilic polysaccharide alcohol in a mass ratio of (1-3):(1-2):(10-11):(5-7).

2. The method for preparing the card unblocking agent according to claim 1, characterized in that, The polyglycerol fatty acid esters include one or more of polyglycerol-4 isostearate, polyglycerol dioleate, and polyglycerol-3 diisostearate.

3. The method for preparing the card unblocking agent according to claim 1, characterized in that, The hydrophilic polysaccharide alcohol includes one or both of xylitol and sorbitol.

4. The method for preparing the card unblocking agent according to claim 1, characterized in that, The uniform mixing includes: Polyglycerol fatty acid ester, stearic acid monoethanolamide, isooctyl alcohol polyoxyethylene ether monophosphate and hydrophilic polysaccharide alcohol were added to the reaction vessel and stirred for the first time. Then heat and stir a second time. Once the mixture is homogeneous, stop heating and continue stirring until the temperature drops below 40°C.

5. The method for preparing the card unblocking agent according to claim 4, characterized in that, The first stirring time is 25 min to 35 min; the second stirring time is 40 min to 1.5 h; and the heating temperature is 50℃ to 80℃.

6. A card release agent, characterized in that, The unblocking agent can be prepared by the method described in any one of claims 1-5.

7. A method for preparing an ultra-high density card unlocking solution, characterized in that, The method includes: Add calcium chloride and potassium chloride to water in sequence, stir well, and a brine phase is obtained; Add the unblocking agent according to claim 6 to the oil phase, stir evenly, and obtain the intermediate product; The brine phase and intermediate product were mixed evenly to obtain a water-in-oil emulsion; Add a viscosity reducer and barite to the water-in-oil emulsion and stir until homogeneous to obtain the unblocking solution.

8. The method for preparing the ultra-high density card unlocking solution according to claim 7, characterized in that, The mass ratio of the oil phase, viscosity reducer, water, calcium chloride, potassium chloride and unblocking agent is (70-95):(3-5):(5-30):(1-3):(0.5-2):(30-50).

9. The method for preparing the ultra-high density card unlocking solution according to claim 7, characterized in that, The amount of barite used is determined according to the required density.

10. The method for preparing the ultra-high density card unlocking solution according to claim 7, characterized in that, The oil phase includes diesel or white oil.

11. The method for preparing the ultra-high density card unlocking solution according to claim 7, characterized in that, The viscosity reducer includes polyamide compounds.

12. The method for preparing the ultra-high density card unlocking solution according to claim 7, characterized in that, All stirring during the preparation process is done by electric stirring at a speed of 50–60 r / min.

13. A high-density card unlocking solution, characterized in that, The card-unblocking solution is prepared by the method described in any one of claims 7-12.

14. The application of the unsticking agent of claim 6 or the ultra-high density unsticking fluid of claim 13 in drilling unsticking operations.

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