Background
Drilling fluids are well-drilled "blood" and are of great importance in oil exploration and development. With the increase of well depth, the drilling fluid can generate the phenomena of high-temperature thickening, thickening reduction, poor solid phase increase, water loss increase, solidification and the like. The ultra-high temperature technology of drilling fluid above 200 ℃ is a worldwide difficult problem, and the main treating agent is monopolized by a plurality of foreign petroleum companies for a long time. The prior domestic ultra-high temperature drilling fluid has the following difficulties: (1) The high temperature resistance stability of the drilling fluid is poor, and the temperature of the trisulfonic drilling fluid system can be 160 ℃ to 190 ℃; (2) high formation pressure and more pressure systems; (3) The geological condition is complex, the open hole section of the ultra-deep well is long, the well wall instability is serious, and the drilling fluid treating agent and the drilling fluid technology resistant to the temperature of more than 200 ℃ are required to be researched.
The existing drilling aids mainly have a single effect, and when a plurality of drilling fluid aids are added simultaneously, side effects of mutual influence can occur among the aids. Particularly, the lubricant, the defoamer, the asphalt anti-collapse plugging agent and the anti-balling agent containing the active agent are different in the active agent used by different products, and the active agent is different in groups, temperature resistance and addition amount when the active agent is used, so that the effect of the product is greatly reduced and sometimes obvious adverse effects such as emulsification thickening, foaming, demulsification and the like can occur when the active agent is added into a well.
At present, the multifunctional auxiliary agent for the drilling fluid mainly combines the viscosity effect and the water loss reducing effect. Products with anti-collapse plugging performance, lubricating performance, inhibiting performance and filtrate reducing performance are mainly realized by virtue of single effects of different products. The anti-collapse plugging products mainly comprise asphalt, the lubricants mainly comprise oil-based and water-based liquid lubricants and solid lubricants, the surface tension of the lubricants is changed through an active agent, the inhibition performance is mainly that the inhibition performance of drilling fluid is improved through cationic products, and the filtrate reducer mainly comprises the filtrate loss of the whole drilling fluid. Many anti-collapse plugging agent asphalts are formulated with a certain amount of active agent in order to allow adequate dispersion of the asphalt in the drilling fluid, and the types of emulsifiers vary from manufacturer to manufacturer. Many oil-based lubricants incorporate an amount of active agent into the lubricant in order to provide better lubrication of the product. When the products are added into the drilling fluid at the same time, the phenomena of demulsification, foaming, thickening and the like of different types of emulsifying agents occur, and more drilling fluid auxiliary agents are needed to be added for performance adjustment in order to adjust the performance of the drilling fluid. Along with the increase of the well temperature, when the auxiliary agents of different drilling fluids of different functions of different manufacturers jointly act on the same drilling fluid under the condition of no comprehensive and long-time reaction test, the auxiliary agents can also generate side effects, so that the inferior solid phase is increased, and the performance of the drilling fluid is reduced. Therefore, a drilling fluid auxiliary agent with multiple effects is needed, has multiple effects of high temperature resistance, collapse prevention, blocking lubrication, fluid loss reduction and the like, can replace lubricants, inhibitors and the like which are used in the drilling fluid in a small amount and are easy to cause side effects, and improves the collapse prevention blocking performance and the fluid loss reduction performance of the drilling fluid.
Disclosure of Invention
The invention provides a multifunctional auxiliary agent for drilling fluid, which overcomes the defects of the prior art, and can effectively solve the problems that the existing drilling auxiliary agent has single action and is easy to cause side effects.
One of the technical schemes of the invention is realized by the following measures: the multifunctional auxiliary agent for the drilling fluid comprises the following raw materials in parts by mass: 30 to 60 parts of base oil, 2 to 10 parts of suspending agent, 10 to 20 parts of active agent, 30 to 50 parts of asphalt, 5 to 20 parts of acidulant and 5 to 20 parts of neutralizing agent.
The following are further optimizations and/or improvements to one of the above-described inventive solutions:
The base oil is mineral oil with flash point not less than 100 ℃.
The base oil is one or more of waste lubricating oil, waste heat conducting oil and waste white oil.
The suspending agent is one or two of superfine dispersion synthetic fibers of 500 meshes to 1000 meshes and superfine resin fibers of 300 meshes to 800 meshes.
The active agent is one or more of span 80, OP-10, methyl oleate and sodium dodecyl benzene sulfonate.
The asphalt is one or more of solid high-temperature asphalt, natural mineral asphalt, coal asphalt and petroleum asphalt.
The acidulant is one or more of sulfamic acid, propanesulfonic acid, dilute nitric acid and stearic acid.
The neutralizing agent is sodium hydroxide or potassium hydroxide.
The multifunctional auxiliary agent for the drilling fluid is prepared by the following steps:
firstly, adding required amount of base oil and asphalt into a reaction container, heating to 90-100 ℃, and stirring and mixing uniformly to obtain a first mixed solution;
secondly, adding a required amount of acidulant into the first mixed solution, and stirring and reacting for 2 to 4 hours at the temperature of 90 to 100 ℃ to obtain a second mixed solution;
Thirdly, cooling the reaction kettle to 60-70 ℃, adding a neutralizing agent into the second mixed solution to neutralize the pH value to 9-10, and uniformly stirring to obtain a third mixed solution;
and fourthly, adding a suspending agent and an active agent into the third mixed solution, stirring and reacting for 1 to 4 hours at a constant temperature under the condition of 50 to 60 ℃ to obtain a uniform suspension, and cooling to the normal temperature to obtain the multifunctional auxiliary agent for the drilling fluid.
The second technical scheme of the invention is realized by the following measures: a preparation method of a multifunctional auxiliary agent for drilling fluid comprises the following steps:
firstly, adding required amount of base oil and asphalt into a reaction container, heating to 90-100 ℃, and stirring and mixing uniformly to obtain a first mixed solution;
secondly, adding a required amount of acidulant into the first mixed solution, and stirring and reacting for 2 to 4 hours at the temperature of 90 to 100 ℃ to obtain a second mixed solution;
Thirdly, cooling the reaction kettle to 60-70 ℃, adding a neutralizing agent into the second mixed solution to neutralize the pH value to 9-10, and uniformly stirring to obtain a third mixed solution;
and fourthly, adding a suspending agent and an active agent into the third mixed solution, stirring and reacting for 1 to 4 hours at a constant temperature under the condition of 50 to 60 ℃ to obtain a uniform suspension, and cooling to the normal temperature to obtain the multifunctional auxiliary agent for the drilling fluid.
The following is a further optimization and/or improvement of the second technical scheme of the invention:
The stirring rate in the first step, the second step and the third step is 300 rpm, and the stirring rate in the fourth step is 200 rpm.
The multifunctional auxiliary agent for the drilling fluid has no strict requirement on the drilling fluid system, compared with the prior drilling fluid system materials, the types of the base oil and the active agent in the raw materials can be reduced by 1 to 3, the lubricity of the performance of the oil-based drilling fluid system is improved, the asphalt materials in the raw materials can be used for increasing the collapse prevention and blocking performance of the drilling fluid, the acidification reaction and the neutralization reaction in the drilling fluid can be used for improving the high-temperature high-pressure fluid loss reduction rate of the drilling fluid, the poor solid phase dispersion can be obviously inhibited in practical application, the mud cake adhesion coefficient of the water-based or oil-based drilling fluid can be reduced, the collapse and the stuck drilling of the well wall can be prevented, the fluidity of the drilling fluid can be improved, the annulus flow resistance can be reduced, and the portability of the drilling fluid and the inhibition of drill cuttings can be improved. Meanwhile, the multifunctional auxiliary agent for the drilling fluid can replace and reduce the addition of functional materials in the drilling fluid, and reduce the production cost.
Detailed Description
The present invention is not limited by the following examples, and specific embodiments can be determined according to the technical scheme and practical situations of the present invention. The various chemical reagents and chemical supplies mentioned in the invention are all commonly known and used in the prior art unless specified otherwise; the percentages in the invention are mass percentages unless specified otherwise; the room temperature and the room temperature in the present invention generally refer to temperatures ranging from 15 ℃ to 25 ℃, and are generally defined as 25 ℃.
The invention is further described below with reference to examples:
Example 1: the multifunctional auxiliary agent for the drilling fluid comprises the following raw materials in parts by mass: 30 to 60 parts of base oil, 2 to 10 parts of suspending agent, 10 to 20 parts of active agent, 30 to 50 parts of asphalt, 5 to 20 parts of acidulant and 5 to 20 parts of neutralizing agent.
Example 2: as optimization of the embodiment, the multifunctional auxiliary agent for the drilling fluid comprises the following raw materials in parts by mass: 30 parts or 60 parts of base oil, 2 parts or 10 parts of suspending agent, 10 parts or 20 parts of active agent, 30 parts or 50 parts of asphalt, 5 parts or 20 parts of acidulant and 5 parts or 20 parts of neutralizing agent.
Example 3: as an optimization of the above embodiment, the base oil is one or more of waste lubricating oil, waste heat transfer oil, and waste white oil. Wherein, the waste lubricating oil can be waste hydraulic oil, waste gear oil, waste gasoline engine oil and waste diesel engine oil. The waste heat transfer oil may be used heat transfer oil which has been replaced.
Example 4: as an optimization of the above embodiment, the suspending agent is one or both of 500 mesh to 1000 mesh ultra-fine dispersion type synthetic fibers and 300 mesh to 800 mesh ultra-fine resin fibers.
Example 5: as an optimization of the above examples, the active agent is one or more of span 80, OP-10, methyl oleate and sodium dodecyl benzene sulfonate.
Example 6: as an optimization of the above embodiment, the asphalt is one or more of solid high temperature asphalt, natural mineral asphalt, coal asphalt, and petroleum asphalt.
Example 7: as an optimization of the above examples, the acidulant is one or more of sulfamic acid, propanesulfonic acid, dilute nitric acid and stearic acid. In practical application, acidulants with different water contents can be selected according to requirements, and solid acid or anhydrous acidulants can be adopted when zero water content products are needed.
Example 8: as an optimization of the above examples, the neutralizing agent is sodium hydroxide or potassium hydroxide.
Example 9: the preparation method of the multifunctional auxiliary agent for the drilling fluid comprises the following steps:
firstly, adding required amount of base oil and asphalt into a reaction container, heating to 90-100 ℃, and stirring and mixing uniformly to obtain a first mixed solution;
secondly, adding a required amount of acidulant into the first mixed solution, and stirring and reacting for 2 to 4 hours at the temperature of 90 to 100 ℃ to obtain a second mixed solution;
Thirdly, cooling the reaction kettle to 60-70 ℃, adding a neutralizing agent into the second mixed solution to neutralize the pH value to 9-10, and uniformly stirring to obtain a third mixed solution;
and fourthly, adding a suspending agent and an active agent into the third mixed solution, stirring and reacting for 1 to 4 hours at a constant temperature under the condition of 50 to 60 ℃ to obtain a uniform suspension, and cooling to the normal temperature to obtain the multifunctional auxiliary agent for the drilling fluid.
Example 10: as an optimization of the above example 9, the stirring rate in the first, second and third steps was 300 rpm, and the stirring rate in the fourth step was 200 rpm.
The invention utilizes mineral oil and asphalt to produce multifunctional auxiliary agent for drilling fluid, adds asphalt into mineral oil, and makes acidification reaction under the action of acidifying agent and heating, then adds the mixed liquor obtained after neutralization reaction of neutralizing agent, finally adds suspending agent and active agent into the mixed liquor to form stable high-solid-phase low-residue stable suspension so as to obtain the multifunctional auxiliary agent for drilling fluid. The multifunctional liquid auxiliary agent for the drilling fluid has multiple functions of high temperature resistance, strong inhibition, collapse prevention and blocking resistance, lubricity and fluid loss reduction. Wherein, the mineral oil can adopt recovered waste oil products, thereby realizing the recycling of wastes.
Example 11: the preparation method of the multifunctional auxiliary agent for the drilling fluid comprises the following steps:
Firstly, adding 50 parts of waste lubricating oil (the flash point is more than or equal to 150 ℃) and 40 parts of solid high-temperature asphalt (the softening point is more than or equal to 180 ℃) into a reaction kettle; heating to 95 ℃, stirring at constant temperature, dispersing and dissolving for 0.5 hour until the mixture is uniformly mixed to obtain a first mixed solution; secondly, adding 5 parts of sulfamic acid and 15 parts of 5% nitric acid aqueous solution (v/v) into the first mixed solution, and stirring and reacting for 2 hours to complete acidification to obtain a second mixed solution; thirdly, cooling the reaction kettle to 60-70 ℃, adding 5 parts of 35% potassium hydroxide aqueous solution into the second mixed solution, and adjusting the pH value to 9-10, wherein the process is controlled within 1 hour, so as to obtain a third mixed solution; and a fourth step of adding 6 parts of superfine resin fibers with the particle size of 300 meshes and 5 parts of methyl oleate into the third mixed solution. Stirring at a constant temperature of 50-60 ℃ for reaction for 3 hours, adding 5 parts of span 80 into a reaction kettle, and fully stirring at a constant temperature for reaction for 1 hour to fully combine residual water molecules; cooling to normal temperature to obtain the multifunctional auxiliary agent for drilling fluid. Wherein the stirring rate in the first step, the second step and the third step is 300 rpm, and the stirring rate in the fourth step is 200 rpm.
The multifunctional auxiliary agent for the drilling fluid, which is obtained by the embodiment, is mainly applied to an ultra-deep well drilling fluid system, can resist high temperature up to 240 ℃, and can replace the use of anti-collapse plugging agents, lubricants, filtrate reducers and defoamers in the ultra-deep well drilling fluid. In the embodiment, the waste lubricating oil is used as the base oil, and the characteristics of high flash point, high temperature resistance and difficult esterification and high temperature decomposition of the waste lubricating oil are utilized; the solid high-temperature asphalt has the characteristic of high softening point, and has the advantage of good anti-collapse plugging effect in an ultra-deep well drilling fluid system; the addition of the active agent enables free water in the whole finished suspension to be fully combined with the reacted mixed liquid, and improves the stability of the multifunctional auxiliary agent for drilling fluid.
Example 12: the preparation method of the multifunctional auxiliary agent for the drilling fluid comprises the following steps:
Firstly, adding 50 parts of waste non-fluorescent white oil and 40 parts of petroleum asphalt into a reaction kettle, heating to 90 ℃, stirring at constant temperature, dispersing and dissolving for 0.5 hour until the mixture is uniformly mixed to obtain a first mixed solution; secondly, adding 5 parts of propane sulfonic acid and 10 parts of 5% nitric acid aqueous solution (v/v) into a reaction kettle, and stirring and reacting for 2 hours to complete acidification to obtain a second mixed solution; thirdly, cooling the reaction kettle to 60-70 ℃, adding 5 parts of 35% potassium hydroxide aqueous solution into the reaction kettle, and adjusting the pH value to 9-10, wherein the process is controlled within 1 hour, so as to obtain a third mixed solution; and fourthly, adding 6 parts of superfine resin fibers with the particle size of 300 meshes and 10 parts of span 80 into the third mixed solution, stirring at a constant temperature of 50-60 ℃ for reaction for 2 hours, and cooling to the normal temperature to obtain the multifunctional auxiliary agent for the drilling fluid. Wherein the stirring rate in the first step, the second step and the third step is 300 rpm, and the stirring rate in the fourth step is 200 rpm.
The multifunctional auxiliary agent for the drilling fluid, which is obtained by the embodiment, is mainly applied to a key exploratory well drilling fluid system, has the characteristic of low fluorescence, and can replace the use of anti-collapse plugging agents, lubricants, filtrate reducers and defoamers in the drilling fluid. White oil is selected as base oil and petroleum asphalt is added, so that the well logging operation can be smoothly carried out in the well drilling process, and the difficulty in the well logging operation is prevented from being increased by adding other types of asphalt products.
Example 13: the preparation method of the multifunctional auxiliary agent for the drilling fluid comprises the following steps:
Firstly, adding 40 parts of waste heat-conducting oil and 30 parts of natural mineral asphalt into a reaction kettle, heating to 95 ℃, stirring at constant temperature, dispersing and dissolving for 0.5 hour until the materials are uniformly mixed to obtain a first mixed solution; secondly, adding 5 parts of sulfamic acid and 15 parts of 5% nitric acid aqueous solution (v/v) into the first mixed solution, and stirring and reacting for 2 hours to complete acidification to obtain a second mixed solution; thirdly, cooling the reaction kettle to 65 ℃, adding 10 parts of 20% sodium hydroxide aqueous solution into the second mixed solution, and adjusting the pH value to 9-10 to obtain a third mixed solution; and fourthly, adding 6 parts of ultra-fine dispersion synthetic polyester fibers with the particle size of 500 meshes and 15 parts of OP-10 into the third mixed solution, stirring and reacting for 3 hours at a constant temperature under the condition of 50-60 ℃, and cooling to the normal temperature to obtain the multifunctional auxiliary agent for the drilling fluid. Wherein the stirring rate in the first step, the second step and the third step is 300rpm, and the stirring rate in the fourth step is 200 rpm.
The multifunctional auxiliary agent for the drilling fluid, which is obtained by the embodiment, is mainly applied to a common drilling fluid system, has relatively low preparation cost, can resist the temperature to 200 ℃, and can replace anti-collapse plugging agents, lubricants, filtrate reducers and defoamers in the drilling fluid. In practical application, the cost of the drilling fluid system formula can be reduced by 10 ten thousand to 30 ten thousand RMB per well.
Performance tests of the multifunctional auxiliary agents for drilling fluids prepared in examples 11 to 13 are shown in table 1. As can be seen from Table 1, the multifunctional auxiliary agent for drilling fluid has the temperature resistance of more than 200 ℃, the lubrication coefficient reduction rate higher than the industry standard requirement (65%), the high-temperature high-pressure reduction rate not less than 28.0%, the solid phase content higher than 30%, the burning residue lower than 5.0%, the R3 reading value measured by a six-speed rotary viscometer after maintenance at 200 ℃ not less than 3, and the core expansion reduction rate higher than 90.0%. In addition, the multifunctional auxiliary agent for the drilling fluid can not be coagulated at the temperature of 20 ℃ below zero, can still keep good fluidity, and can be added into water-based or oil-based drilling fluid to have good compatibility with the drilling fluid.
The well slurry (anti-180 ℃ potassium-calcium-based polysulfonate drilling fluid system) of the original Sankancertain well drilling fluid in the northwest China is selected for practical application test. The well slurry of the drilling fluid has the conditions of foaming, increased filtration loss and poor stability of the drilling fluid at 180 ℃. 3.0% and 5.0% of the multifunctional auxiliary agent for drilling fluid prepared in example 11 are respectively added into the drilling fluid slurry, and test results are shown in table 2 (AV, PV, YP, FL, kf, HTHP in table 2 are apparent viscosity, plastic viscosity, dynamic shear force, medium-pressure water loss, friction coefficient and high-temperature high-pressure water loss of the drilling fluid respectively). As can be seen from Table 2, after the multifunctional auxiliary agent for drilling fluid is added, the water loss of the drilling fluid and the well slurry is obviously reduced, the dynamic shear force is obviously increased, and the friction coefficient is also obviously reduced.
In summary, the multifunctional auxiliary agent for the drilling fluid provided by the invention overcomes the defect of single efficacy of the auxiliary agent for the drilling fluid in China at present, has the effects of high temperature resistance, collapse prevention, plugging lubrication, filtration reduction and the like, can reduce or avoid using less lubricant, inhibitor and other additives which are easy to cause side effects in the drilling fluid, improves the collapse prevention and plugging performance and filtration reduction performance of the drilling fluid, can effectively reduce the generation of poor solid phase in the circulation process of the drilling fluid, and reduces the production cost.
The technical characteristics form the embodiment of the invention, have stronger adaptability and implementation effect, and can increase or decrease unnecessary technical characteristics according to actual needs so as to meet the requirements of different situations.