阅读说明：本技术 钻井液用环保型低荧光封堵剂及其制备方法 (Environment-friendly low-fluorescence plugging agent for drilling fluid and preparation method thereof ) 是由 邓建辉 郑少楠 张俊芳 于 2018-08-23 设计创作，主要内容包括：本发明涉及钻井液用添加剂的技术领域,特别是涉及一种钻井液用环保型荧光封堵剂及其制备方法,该封堵剂荧光强度低,高温下封堵性能良好、更加环保,兼有沥青类产品优良的封堵防塌性能和油层保护作用；该封堵剂由以下组分制备得到,以重量份数计,所述组分包括：丙烯酸35～45份、烧碱20～25份、聚乙二醇2～6份、N,N’-亚甲基双丙烯酰胺0.5～1.5份、淀粉30～50份、轻质CaCO3 10～16份、短棉纤维10～15份,水50～100份,过硫酸铵0.01～0.1份。(The invention relates to the technical field of additives for drilling fluid, in particular to an environment-friendly fluorescent plugging agent for drilling fluid and a preparation method thereof, wherein the plugging agent has low fluorescence intensity, good plugging performance at high temperature, more environmental protection, and excellent plugging anti-collapse performance and oil layer protection function of asphalt products; the blocking agent is prepared from the following components in parts by weight: 35-45 parts of acrylic acid, 20-25 parts of caustic soda, 2-6 parts of polyethylene glycol, 0.5-1.5 parts of N, N' -methylene bisacrylamide, 30-50 parts of starch, 310-16 parts of light CaCO, 10-15 parts of short cotton fiber, 50-100 parts of water and 0.01-0.1 part of ammonium persulfate.)

1. The environment-friendly low-fluorescence plugging agent for drilling fluid is characterized by being prepared from the following components in parts by weight: 35-45 parts of acrylic acid, 20-25 parts of caustic soda, 2-6 parts of polyethylene glycol, 0.5-1.5 parts of N, N' -methylene bisacrylamide, 30-50 parts of starch, 310-16 parts of light CaCO, 10-15 parts of short cotton fiber, 50-100 parts of water and 0.01-0.1 part of ammonium persulfate.

2. The environment-friendly low-fluorescence plugging agent for drilling fluid according to claim 1, wherein the polyethylene glycol is PEG-2000.

3. The environment-friendly low-fluorescence plugging agent for drilling fluid according to claim 2, characterized in that the manufacturing method is as follows:

adding 50-100 parts of water into a reaction kettle, adding 20-25 parts of caustic soda, stirring for dissolving, cooling to below 40 ℃, adding 35-45 parts of acrylic acid while stirring, cooling to below 40 ℃, adding 0.5-1.5 parts of N, N' -methylene bisacrylamide, stirring for dissolving, adding 2-6 parts of polyethylene glycol, heating to 50-60 ℃, adding 30-50 parts of starch, 310-16 parts of light CaCO and 10-15 parts of short cotton fiber, stirring for 30 minutes, keeping the temperature at 50-60 ℃, adding 0.01-0.1 part of ammonium persulfate, reacting for 1.5 hours, discharging, drying and crushing to obtain the product.

4. The preparation method of the environment-friendly low-fluorescence plugging agent for drilling fluid according to claim 3, wherein the stirring speed is 40-50 r/min.

5. The preparation method of the environment-friendly low-fluorescence plugging agent for drilling fluid as claimed in claim 4, wherein the particle size of the product is 80 mesh, and the passing rate of the product is not less than 90%.

Technical Field

The invention relates to the technical field of additives for drilling fluid, in particular to an environment-friendly fluorescent plugging agent for drilling fluid and a preparation method thereof.

Background

As is well known, although asphalt, paraffin, and polyalcohol plugging agents have been developed in the prior art of drilling fluids, and have good plugging effects under certain conditions, the asphalt has high fluorescence level, and is only practical in production wells in low environmental protection requirement areas, the paraffin and polyalcohol are easy to bubble, and the viscosity of the drilling fluid is easy to greatly increase, and meanwhile, after the bottom temperature of the well exceeds the melting point of the product, the plugging effect is lost, and the requirement of anti-collapse drilling fluid cannot be met.

Disclosure of Invention

The invention aims to solve the first technical problem of providing the environment-friendly low-fluorescence plugging agent for the drilling fluid, which has low fluorescence intensity, good plugging performance at high temperature and more environment protection.

The invention relates to an environment-friendly low-fluorescence plugging agent for drilling fluid, which is prepared from the following components in parts by weight: 35-45 parts of acrylic acid, 20-25 parts of caustic soda, 2-6 parts of polyethylene glycol, 0.5-1.5 parts of N, N' -methylene bisacrylamide, 30-50 parts of starch, 310-16 parts of light CaCO, 10-15 parts of short cotton fiber, 50-100 parts of water and 0.01-0.1 part of ammonium persulfate.

The environment-friendly low-fluorescence plugging agent for the drilling fluid is characterized in that the polyethylene glycol is PEG-2000.

The second technical problem to be solved by the invention is to provide a preparation method of the environment-friendly low-fluorescence plugging agent for drilling fluid, which comprises the following steps:

adding 50-100 parts of water into a reaction kettle, adding 20-25 parts of caustic soda, stirring for dissolving, cooling to below 40 ℃, adding 35-45 parts of acrylic acid while stirring, cooling to below 40 ℃, adding 0.5-1.5 parts of N, N' -methylene bisacrylamide, stirring for dissolving, adding 2-6 parts of polyethylene glycol, heating to 50-60 ℃, adding 30-50 parts of starch, 310-16 parts of light CaCO and 10-15 parts of short cotton fiber, stirring for 30 minutes, keeping the temperature at 50-60 ℃, adding 0.01-0.1 part of ammonium persulfate, reacting for 1.5 hours, discharging, drying and crushing to obtain the product.

The preparation method of the environment-friendly low-fluorescence plugging agent for the drilling fluid has the advantage that the stirring speed is 40-50 r/min.

According to the preparation method of the environment-friendly low-fluorescence plugging agent for the drilling fluid, the particle size of the product is 80 meshes, and the passing rate of the product is more than or equal to 90%.

Compared with the prior art, the invention has the beneficial effects that: the product of the invention is powdery, the raw materials are easy to obtain, and the cost is greatly reduced; the fluorescent material has a low fluorescence level, and cannot interfere with geological logging; the toxicity is low, and the biological degradation can be realized, thereby being beneficial to protecting the environment; the plugging and anti-collapse agent has excellent plugging and anti-collapse performance, is suitable for various complex stratums, and has good compatibility, low dosage and obvious effect; the drilling fluid can be used while drilling in the using process, and has small influence on the rheological property and the pH value of the drilling fluid; in addition, the product has good lubricating property and fluid loss reduction property, and the oil-gas reservoir can be protected by the degradable property of the product.

Detailed Description

The invention aims to solve the first technical problem of providing the environment-friendly low-fluorescence plugging agent for the drilling fluid, which has low fluorescence intensity, good plugging performance at high temperature and more environment protection.

The invention relates to an environment-friendly low-fluorescence plugging agent for drilling fluid, which is prepared from the following components in parts by weight: 35-45 parts of acrylic acid, 20-25 parts of caustic soda, 2-6 parts of polyethylene glycol, 0.5-1.5 parts of N, N' -methylene bisacrylamide, 30-50 parts of starch, 310-16 parts of light CaCO, 10-15 parts of short cotton fiber, 50-100 parts of water and 0.01-0.1 part of ammonium persulfate.

The environment-friendly low-fluorescence plugging agent for the drilling fluid is prepared by using PEG-2000 as polyethylene glycol.

The second technical problem to be solved by the invention is to provide a preparation method of the environment-friendly low-fluorescence plugging agent for drilling fluid, which comprises the following steps:

adding 50-100 parts of water into a reaction kettle, adding 20-25 parts of caustic soda, stirring for dissolving, cooling to below 40 ℃, adding 35-45 parts of acrylic acid while stirring, cooling to below 40 ℃, adding 0.5-1.5 parts of N, N' -methylene bisacrylamide, stirring for dissolving, adding 2-6 parts of polyethylene glycol, heating to 50-60 ℃, adding 30-50 parts of starch, 310-16 parts of light CaCO and 10-15 parts of short cotton fiber, stirring for 30 minutes, keeping the temperature at 50-60 ℃, adding 0.01-0.1 part of ammonium persulfate, reacting for 1.5 hours, discharging, drying and crushing to obtain the product.

The preparation method of the environment-friendly low-fluorescence plugging agent for the drilling fluid has the advantage that the stirring speed is 40-50 r/min.

According to the preparation method of the environment-friendly low-fluorescence plugging agent for the drilling fluid, the particle size of the product is 80 meshes, and the passing rate of the product is more than or equal to 90%.

The product of the invention is obtained by creative work of an inventor, the inventor carries out cross-linking polymerization on acrylic acid, caustic soda, starch, N' -methylene bisacrylamide, starch and the like, and simultaneously introduces cotton fiber and calcium carbonate, so that the product can form deformable toughness particles to block microcracks of a stratum and pore gaps of a permeable stratum, and meanwhile, the cotton fiber can be mutually matched and connected into a net structure to prevent drilling fluid from permeating into the deep part of the stratum; and the cotton fiber can improve the compactness, the stretchability, the toughness and the adhesive force of a well wall of the mud cake under the action of pressure, so that the product has stronger capabilities of plugging cracks, stabilizing the rheological property of slurry and improving the quality of the mud cake. Meanwhile, as the raw materials of the product are mainly acrylic acid, caustic soda, calcium carbonate, fiber and the like, the product has a lower fluorescence level, is biodegradable and is beneficial to environmental protection; the product has excellent plugging and anti-collapse performance of asphalt products and oil layer protection function.

The following examples are given to further illustrate the embodiments of the present invention. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.