阅读说明：本技术 一种油气勘探钻井废弃水基钻井液调配工艺 (Blending process of waste water-based drilling fluid for oil and gas exploration drilling ) 是由 张坤 周华安 陈立荣 罗宇峰 邓宇 蒋学彬 李辉 于 2020-03-23 设计创作，主要内容包括：本发明公开了一种油气勘探钻井废弃水基钻井液调配工艺,其包括对废弃水基钻井液进行处理的步骤和改造胶液制备步骤；以质量百分比计,在清水中加入0.5～2%腐殖酸钾KHm、0.2%NaOH、0.2%CaO、0.5～1.0%两性离子聚合物降粘剂CJ5-1、0.5～1%封堵润滑剂DHD、1～2%磺化酚醛树脂SMP-1和1～3%KCl,其余为清水；然后将制备好的改造胶液与处理后的废弃水基钻井液按照20～30：80～70进行混合,完成对废弃水基钻井液的调配。采用本工艺方法,使得废弃钻井液具有良好的流变性、较高的润滑性、较好的稳定性,较强的抗温、抗膏盐、抗盐水污染能力,并且易于维护处理。(The invention discloses a blending process of waste water-based drilling fluid for oil-gas exploration drilling, which comprises the steps of treating the waste water-based drilling fluid and preparing modified glue solution; according to the mass percentage, 0.5-2% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5-1.0% of zwitterionic polymer viscosity reducer CJ5-1, 0.5-1% of blocking lubricant DHD, 1-2% of sulfonated phenolic resin SMP-1 and 1-3% of KCl are added into clear water, and the balance is clear water; then mixing the prepared modified glue solution with the treated waste water-based drilling fluid according to the weight ratio of 20-30: 80-70, and finishing the blending of the waste water-based drilling fluid. By adopting the process method, the waste drilling fluid has good rheological property, higher lubricity, better stability, stronger temperature resistance, paste salt resistance and saline water pollution resistance, and is easy to maintain and treat.)

1. A blending process of waste water-based drilling fluid for oil and gas exploration drilling is characterized by comprising a step of treating the waste water-based drilling fluid and a step of preparing modified glue solution; the waste water-based drilling fluid is treated by controlling the solid content and the sand content in the waste water-based drilling fluid; the preparation steps of the modified glue solution are as follows: according to the mass percentage, 0.5-2% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5-1.0% of zwitterionic polymer viscosity reducer CJ5-1, 0.5-1% of blocking lubricant DHD, 1-2% of sulfonated phenolic resin SMP-1 and 1-3% of KCl are added into clear water, and the balance is clear water; then mixing the prepared modified glue solution with the treated waste water-based drilling fluid according to the weight ratio of 20-30: 80-70, and finishing the blending of the waste water-based drilling fluid.

2. The blending process of the waste water-based drilling fluid for oil and gas exploration drilling according to claim 1, wherein the blending process comprises the following steps: the waste water-based drilling fluid is treated by a vibrating screen, a sand remover, a mud remover and a centrifuge, the solid content in the waste drilling fluid is controlled within a drilling design range, and the sand content is controlled to be below 0.5%.

3. The blending process of the waste water-based drilling fluid for oil and gas exploration drilling according to claim 1, wherein the blending process comprises the following steps: the preparation steps of the modified glue solution are as follows: according to the mass percentage, 1.5 percent of potassium humate KHm, 0.2 percent of NaOH, 0.2 percent of CaO, 1 percent of zwitterionic polymer viscosity reducer CJ5-1, 1 percent of blocking lubricant DHD, 1 percent of sulfonated phenolic resin SMP-1 and 2 percent of KCl are added into clear water; the balance being clear water.

4. The blending process of the waste water-based drilling fluid for oil and gas exploration drilling according to claim 1, wherein the blending process comprises the following steps: the preparation steps of the modified glue solution are as follows: according to the mass percentage, 0.5 percent of potassium humate KHm, 0.2 percent of NaOH, 0.2 percent of CaO, 0.5 percent of zwitterionic polymer viscosity reducer CJ5-1, 0.5 percent of blocking lubricant DHD, 1 percent of sulfonated phenolic resin SMP-1 and 1 percent of KCl are added into clear water; the balance being clear water.

5. The blending process of the waste water-based drilling fluid for oil and gas exploration drilling according to claim 1, wherein the blending process comprises the following steps: the preparation steps of the modified glue solution are as follows: according to the mass percentage, 1% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5% of zwitterionic polymer viscosity reducer CJ5-1, 0.5% of blocking lubricant DHD, 1% of sulfonated phenolic resin SMP-1 and 2% of KCl are added into clear water; the balance being clear water.

6. The blending process of the waste water-based drilling fluid for oil and gas exploration drilling according to claim 1, wherein the blending process comprises the following steps: the preparation steps of the modified glue solution are as follows: according to the mass percentage, 2% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5% of zwitterionic polymer viscosity reducer CJ5-1, 1% of blocking lubricant DHD, 2% of sulfonated phenolic resin SMP-1 and 3% of KCl are added into clear water; the balance being clear water.

Technical Field

The invention relates to the technical field of petroleum and natural gas drilling, in particular to a blending process of waste water-based drilling fluid for oil and gas exploration drilling.

Background

As blood in the process of drilling petroleum and natural gas, the drilling fluid is indispensable for ensuring the normal operation of the drilling fluid, and can play roles in balancing the formation pressure, carrying and suspending drill cuttings, cleaning the well bottom, protecting the well wall, cooling and lubricating a drilling tool, transmitting power and the like. In order to ensure the exertion of the functions, various organic and inorganic drilling fluid treating agents are generally added into the drilling fluid, such as lignite, sulfonated tannin, carboxymethyl cellulose, potassium polyacrylate, partially hydrolyzed polyacrylamide, zwitterionic polymer, sulfonated phenolic resin, sulfomethyl derivative of humic acid, sulfonated or emulsified asphalt and the like, oil, alkali, surfactant, diluent and the like, so that the performance of the modified sulfonated phenolic resin is high and stable, the normal and safe operation of drilling operation is ensured, in particular, the geological structure of the conventional well exploration area of the southwest oil and gas field is complex, the drilled well is deep and is about 4500m on average, in order to ensure safe and rapid drilling, a high-performance drilling fluid system is required to be used, and the performance of the drilling fluid system is required to be high-quality and stable, furthermore, a plurality of different treating agents are usually added for maintenance, and the finally formed drilling fluid components have complex properties and high configuration cost, and generally reach 1000 yuan/m per square.³Left and right. But in the drilling process of oil and natural gas, a large amount of waste drilling fluid is generated, and 1 well of less southwest oil and gas fields is 200-300 m³And many up to 1000m³On the left and right sides, mainly after the drilling operation is finished, most of the wastes remained on the operation site are waste drilling fluid, and due to the field operation characteristics of petroleum drilling, all the wastes in the construction site are almost completely discharged and accumulated in a waste drilling fluid storage pit or a storage tank, so that the harmful components in the drilling wastes are complicated, and finally, the multiphase suspended waste drilling fluid consisting of clay, weighting materials, various chemical treatment agents, sewage, dirty oil, drill cuttings and the like is formed.

The waste drilling fluid is generally alkaline, the pH value is between 8.5 and 12, some waste drilling fluids can reach more than 13, the waste drilling fluid is generally viscous fluid or semi-fluid in appearance, has the characteristics of fine particles, small grading difference, high viscosity, high water content (the water content is about 80 to 90 percent), difficulty in dehydration and the like, is slow in natural drying process, and easily forms the waste drilling fluid again after the dried materials are wetted by water, so that long-term adverse effects can be generated on the physical properties of soil at a discharge point and nearby zones. The solid phase content of the waste drilling fluid is high, the waste drilling fluid mainly comprises bentonite, an organic polymer treating agent, clay, a weighting material, rock debris, silt, surface soil and the like carried by sewage flowing through the ground, the particle size of solid phase particles is generally between 0.01 and 0.3 mu m, namely more than 95 percent of particles pass through a 200-mesh sieve.

If the waste drilling fluid is recycled, in order to meet the requirement of drilling operation, the waste drilling fluid needs to be modified, so that the modified drilling fluid meets the following requirements: good rheological properties to meet the need for cuttings carry and shaft bottom cleaning in deviated and even horizontal sections; the high lubricity is used for reducing the friction resistance of tripping the drill bit, and the occurrence of underground accidents and complications is avoided; better stability, temperature resistance, paste and salt resistance, saline pollution resistance and easy maintenance and treatment; the strong water loss wall-building property stabilizes the well wall, prevents the well wall from collapsing due to the water sensitivity of the well wall, and ensures the underground safety.

If Chinese patent document with publication number CN106477758A and publication date of 2017, 3 and 8 discloses a shale gas fracturing flow-back fluid treatment and recycling method, firstly, first-stage air flotation treatment is carried out on water-based fracturing flow-back fluid; after the first-stage air flotation, adding a cationic polymer into the effluent and then performing second-stage air flotation treatment; adding alkaline substances into the effluent after the secondary air flotation, and after full reaction, removing most of high-valence metal ions through microfiltration filtration; and (4) neutralizing to adjust the pH to 6-9 to obtain the final product water-blending liquid. The flowback liquid treated by the method has the COD removal rate of more than 75 percent, the oil removal rate of more than 90 percent, the turbidity of less than 0.1NTU and the removal rate of high-valence metal ions of more than 70 percent, and the obtained water distribution liquid can meet the requirements of preparing water-based fracturing fluid.

The recycling treatment of the existing fracturing flowback fluid represented by the patent documents mainly focuses on controlling metal ions in the fracturing flowback fluid to reach the standard, and then adding a certain proportion of resistance reducing agent to form the standard flowback fluid which is finally injected into the underground. However, the technical problems of poor rheological property, poor lubricity and stability, weak temperature resistance, paste salt resistance and saline water pollution resistance, insufficient water loss wall building property and the like of the existing waste drilling fluid are still not well solved.

Disclosure of Invention

The invention aims at overcoming the defects and shortcomings of the prior art and providing a blending process of waste water-based drilling fluid for oil and gas exploration drilling, and by adopting the process method, the waste drilling fluid has good rheological property, higher lubricity, better stability, stronger temperature resistance, paste and salt resistance and saline pollution resistance, and is easy to maintain and treat; the strong water loss wall-building property stabilizes the well wall, prevents the well wall from collapsing due to the water sensitivity of the well wall, and ensures the underground safety.

The invention is realized by adopting the following technical scheme:

a blending process of waste water-based drilling fluid for oil and gas exploration drilling is characterized by comprising a step of treating the waste water-based drilling fluid and a step of preparing modified glue solution; the waste water-based drilling fluid is treated by controlling the solid content and the sand content in the waste water-based drilling fluid; the preparation steps of the modified glue solution are as follows: according to the mass percentage, 0.5-2% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5-1.0% of zwitterionic polymer viscosity reducer CJ5-1, 0.5-1% of blocking lubricant DHD, 1-2% of sulfonated phenolic resin SMP-1 and 1-3% of KCl are added into clear water, and the balance is clear water; then mixing the prepared modified glue solution with the treated waste water-based drilling fluid according to the weight ratio of 20-30: 80-70, and finishing the blending of the waste water-based drilling fluid.

The waste water-based drilling fluid is treated by a vibrating screen, a sand remover, a mud remover and a centrifuge, the solid content in the waste drilling fluid is controlled within a drilling design range, and the sand content is controlled to be below 0.5%.

The preparation steps of the modified glue solution are as follows: according to the mass percentage, 1.5 percent of potassium humate KHm, 0.2 percent of NaOH, 0.2 percent of CaO, 1 percent of zwitterionic polymer viscosity reducer CJ5-1, 1 percent of blocking lubricant DHD, 1 percent of sulfonated phenolic resin SMP-1 and 2 percent of KCl are added into clear water; the balance being clear water.

The preparation steps of the modified glue solution are as follows: according to the mass percentage, 0.5 percent of potassium humate KHm, 0.2 percent of NaOH, 0.2 percent of CaO, 0.5 percent of zwitterionic polymer viscosity reducer CJ5-1, 0.5 percent of blocking lubricant DHD, 1 percent of sulfonated phenolic resin SMP-1 and 1 percent of KCl are added into clear water; the balance being clear water.

The preparation steps of the modified glue solution are as follows: according to the mass percentage, 1% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5% of zwitterionic polymer viscosity reducer CJ5-1, 0.5% of blocking lubricant DHD, 1% of sulfonated phenolic resin SMP-1, 2% of KCl and the balance of clear water are added into the clear water.

The preparation steps of the modified glue solution are as follows: according to the mass percentage, 2% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5% of zwitterionic polymer viscosity reducer CJ5-1, 1% of blocking lubricant DHD, 2% of sulfonated phenolic resin SMP-1 and 3% of KCl are added into clear water; the balance being clear water.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention adopts a specific preparation method that firstly the solid phase content and the sand content in the waste water-based drilling fluid are controlled, then the modified glue solution is prepared, and particularly the modified glue solution adopts a method that 0.5-2% of potassium humate KHm, 0.2% of NaOH, 0.2% of CaO, 0.5-1.0% of zwitterionic polymer viscosity reducer CJ5-1, 0.5-1% of blocking lubricant DHD, 1-2% of sulfonated phenolic resin SMP-1 and 1-3% of KCl and the balance of clear water are added into clear water according to the mass percentage, then the waste water-based drilling fluid is mixed with the modified glue solution, and the blending of the waste water-based drilling fluid is completed, and the example verification of the embodiment 7 proves that: the modified drilling fluid meets the following requirements: good rheological properties to meet the need for cuttings carry and shaft bottom cleaning in deviated and even horizontal sections; the high lubricity is used for reducing the friction resistance of tripping the drill bit, and the occurrence of underground accidents and complications is avoided; better stability, temperature resistance, paste and salt resistance, saline pollution resistance and easy maintenance and treatment; the strong water loss wall-building property stabilizes the well wall, prevents the well wall from collapsing due to the water sensitivity of the well wall, and ensures the underground safety.

2. In the invention, the prepared modified glue solution and the treated waste water-based drilling fluid are mixed according to the ratio of 20: 80, and the blending of the waste water-based drilling fluid is completed, and the verification of the example 7 shows that the modified drilling fluid is particularly suitable for adjusting the performance of medium-deep wells, and the modified drilling fluid meets the drilling requirements, has good calcium and salt pollution resistance, and has a guiding effect on the recycling of the waste drilling fluid on site.

3. In the invention, the prepared modified glue solution and the treated waste water-based drilling fluid are mixed according to the ratio of 30: 70, and the blending of the waste water-based drilling fluid is completed, and the verification of the example of the embodiment 7 shows that the modified drilling fluid slurry is particularly suitable for the performance adjustment of deep wells, and the modified drilling fluid slurry meets the drilling requirements, has good calcium and salt pollution resistance, and has a guiding effect on the recycling of the waste drilling fluid on site.

4. The waste water-based drilling fluid is treated by a vibrating screen, a sand remover, a mud remover and a centrifuge, the solid content in the waste drilling fluid is controlled within a drilling design range, and the sand content is controlled to be below 0.5%. Thus, the waste water-based drilling fluid is treated to have the best performance.

5. In the invention, the preparation steps of the modified glue solution are as follows: according to the mass percentage, 1.5 percent of potassium humate KHm, 0.2 percent of NaOH, 0.2 percent of CaO, 1 percent of zwitterionic polymer viscosity reducer CJ5-1, 1 percent of blocking lubricant DHD, 1 percent of sulfonated phenolic resin SMP-1 and 2 percent of KCl are added into clear water; the balance being clear water. The specific values are selected, and the examples in example 7 are used for verification, so that the performances of the modified glue solution are best.

Detailed Description