CN-122011256-A - Carbon dioxide pollution resistant filtrate reducer for water-based drilling fluid and preparation method thereof

CN122011256ACN 122011256 ACN122011256 ACN 122011256ACN-122011256-A

Abstract

The invention discloses a carbon dioxide pollution resistant filtrate reducer for water-based drilling fluid and a preparation method thereof, and belongs to the technical field of filtrate reducers for water-based drilling fluid. The filtrate reducer is prepared by sequentially dissolving (1-5) (3-8) (1-5) (0-4) (1-6) monomer N' N-dimethylacrylamide, sodium p-styrenesulfonate, dimethyl diallyl ammonium chloride, N-vinyl pyrrolidone and 2-acrylamide-2-methylpropanesulfonic acid in a solvent, adding an alkali solution to adjust pH, heating, adding an initiator, drying and crushing to obtain the filtrate reducer, wherein the filtrate reducer has stronger competitive adsorption capacity with carbonate and bicarbonate, can improve the performance of drilling fluid, improve the threshold of carbon dioxide accommodation, reduce the risk of uncontrolled filtration performance of the drilling fluid after carbon dioxide pollution, and is suitable for improving the formula of the filtrate reducer for water-based drilling fluid.

Inventors

XU JUNYANG
Xi Yongzheng
FU HAIXIA
XIONG YAPING
Yuan Zongling
HUANG JIAN
SUN JINFENG
WANG XIANZHOU
HE HAONAN
LI HONGMING
XIA JINGGANG
PU LIANGCHUN
SONG YANLI
CAO JIANFENG

Assignees

中国石油集团渤海钻探工程有限公司
中国石油天然气集团有限公司

Dates

Publication Date: 20260512
Application Date: 20241111

Claims (9)

1. The anti-carbon dioxide pollution filtrate reducer for the water-based drilling fluid is characterized in that the raw materials for preparing the effective components comprise a solution I, an alkali solution and an initiator; The solute in the solution I comprises monomer N' N-dimethylacrylamide, sodium p-styrenesulfonate, dimethyl diallyl ammonium chloride, N-vinyl pyrrolidone and 2-acrylamide-2-methylpropanesulfonic acid with the molar ratio of 5 (3-8) (1-5) (0-4) (1-6).
2. The carbon dioxide pollution resistant filtrate reducer for water-based drilling fluids according to claim 1, wherein the alkaline solution is sodium hydroxide solution.
3. The carbon dioxide pollution resistant filtrate reducer for water-based drilling fluids according to claim 2, wherein the initiator is added under stirring at 70-80 ℃.
4. The carbon dioxide pollution resistant fluid loss additive for water based drilling fluids according to claim 3 wherein the initiator is a 1:1 molar ratio of ammonium persulfate to sodium bisulfite mixture.
5. A method for preparing the carbon dioxide pollution resistant filtrate reducer for water-based drilling fluids according to any one of claims 1 to 4, comprising the following steps in sequence: s1, sequentially adding monomer N' N-dimethylacrylamide, sodium p-styrenesulfonate, dimethyl diallyl ammonium chloride, N-vinyl pyrrolidone and 2-acrylamide-2-methylpropanesulfonic acid with a molar ratio of 5 (3-8), 1-5, 0-4 and 1-6 into water, and completely dissolving to obtain a solution I; S2, adding the alkali solution into the solution I, adjusting the pH value and supplementing water to obtain a solution II; S3, heating the solution II, adding an initiator under the stirring condition, and reacting for 1.5-3 hours to obtain a solution IV; s4, drying and crushing the solution IV to obtain the carbon dioxide pollution resistant filtrate reducer.
6. The method for preparing the carbon dioxide pollution resistant filtrate reducer for the water-based drilling fluid, as claimed in claim 5, wherein the pH is adjusted to 5-6.
7. The method of claim 6 wherein the total mass of the water added in the step S2 is 20% -30% of the total mass of the solution II when water is supplemented.
8. The method for preparing the anti-carbon dioxide pollution filtrate reducer for the water-based drilling fluid, which is characterized by firstly adding ammonium persulfate in the initiator into a solution II to obtain a solution III, and then taking sodium bisulphite dissolved in deionized water, and uniformly dripping the sodium bisulphite into the solution III to obtain a solution IV.
9. The method for preparing the carbon dioxide pollution resistant filtrate reducer for the water-based drilling fluid, which is disclosed in any one of claims 6-8, is characterized in that the drying process is carried out at 60-100 ℃.

Description

Carbon dioxide pollution resistant filtrate reducer for water-based drilling fluid and preparation method thereof Technical Field The invention belongs to the technical field of filtrate reducers for water-based drilling fluids, relates to a preparation method of a filtrate reducer for resisting carbon dioxide pollution, and in particular relates to a filtrate reducer for resisting carbon dioxide pollution for water-based drilling fluids and a preparation method thereof. Background With the continuous deep development of oil and gas exploration, the problem of carbon dioxide pollution in the drilling process is increasingly prominent, and the carbon dioxide affects the function of a filtrate reducer for drilling fluid. Because the filtrate reducer has stronger surface activity, can adsorb on clay granule, and the conversion product (such as carbonate and bicarbonate) of carbon dioxide also easily adsorbs on clay granule surface, with filtrate reducer competitive adsorption site to influence the clay granule and to the effective absorption of filtrate reducer, lead to clay granule surface hydration membrane attenuation, flocculation degree increases, causes well drilling liquid flow change and filtrate reducer performance out of control, and corresponding can cause to draw off and hang card, pump pressure increase, open the pump difficulty, face the risk that the wall of a well collapses when serious, make well drilling work be difficult to go on smoothly. Currently, solutions to the problem of carbon dioxide contamination of drilling fluids include prevention of carbon dioxide contamination and post-contamination treatment. The prevention measures comprise using a brine drilling fluid system and a pressure balancing method, wherein the brine slurry adopted by the brine drilling fluid system has stronger pollution resistance, but has higher cost and difficult performance control in the use process, and when the pressure balancing method is used, if a gas measurement value is pressed down, the gas reservoir cannot be found. The most commonly used carbon dioxide pollution post-treatment method is to supplement calcium ions to form precipitates with carbonate, but the method has a great influence on the performance of drilling fluid. In addition, improving the threshold value of carbon dioxide accommodation is one of effective methods for solving the problem that the drilling fluid is polluted by carbon dioxide, for example, chinese patent application CN114292632A discloses a carbon dioxide complexing agent for the drilling fluid and a preparation method and application thereof, but the mass fraction of carbon dioxide which can be complexed is only 0.25%, and the carbon dioxide complexing agent has a single function, so that the cost of the drilling fluid is increased when the drilling fluid is used. Disclosure of Invention In order to solve the defects in the prior art, the invention aims to provide the carbon dioxide pollution resistant filtrate reducer for the water-based drilling fluid, and a novel amphoteric polymer with strong adsorption is prepared by introducing a large side group, a cationic monomer, a rigid structure and a sulfonic group, so that the charge attraction of a bentonite layer with negative charge is improved, the bentonite layer is more competitive with bicarbonate when clay particles are adsorbed, the threshold value of the drilling fluid for carbon dioxide accommodation is improved, and the problem that the filtrate loss performance of the drilling fluid is out of control after carbon dioxide pollution is solved. The invention also aims to provide a preparation method of the carbon dioxide pollution-resistant filtrate reducer for the water-based drilling fluid. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The filtrate reducer for water-base drilling fluid comprises solution I, alkali solution and initiator; as a limitation of the present invention, The solute in the solution I comprises monomer N' N-dimethylacrylamide, sodium p-styrenesulfonate, dimethyl diallyl ammonium chloride, N-vinyl pyrrolidone and 2-acrylamide-2-methylpropanesulfonic acid with the molar ratio of 5 (3-8) (1-5) (0-4) (1-6). Further, N' N-dimethylacrylamide, sodium p-styrenesulfonate, dimethyl diallyl ammonium chloride, N-vinyl pyrrolidone, 2-acrylamide-2-methylpropanesulfonic acid=5, (6-7): (2-3): (1-2): (4-5). As a further definition of the invention, the alkaline solution is sodium hydroxide solution. As still further defined in the present invention, the initiator is added under stirring at 70 ℃ to 80 ℃. As a further definition of the invention, the initiator is a mixture of ammonium persulfate and sodium bisulfite in a molar ratio of 1:1. The invention also provides a preparation method of the carbon dioxide pollution resistant filtrate reducer for the water-based drilling fluid, which comprises the following steps in sequence: S1, sequentially adding monom