High-temperature-resistant salt-resistant anti-collapse filtrate reducer for drilling fluid and preparation method of high-temperature-resistant salt-resistant anti-collapse filtrate reducer

Abstract

The invention discloses a high-temperature-resistant salt-resistant anti-collapse filtrate reducer for a drilling fluid and a preparation method of the High-temperature-resistant salt-resistant anti-collapse filtrate reducer. The key point of the technical scheme is that the high-temperature-resistant salt-resistant anti-collapse filtrate reducer for the drilling fluid is mainly prepared from the following raw materials in parts by weight: 20-35 parts of starch, 0.5-5 parts of caustic soda, 20-40 parts of acrylamide, 5-15 parts of sodium 2-acrylamide-2-methallyl sulfonate, 5-15 parts of diethyl diallyl ammonium chloride, 5-15 parts of sodium pyrosulfite, 5-15 parts of paraformaldehyde and 0.5-5 parts of ammonium persulfate. The invention further discloses a preparation method and a using method of the high-temperature-resistant salt-resistant anti-collapse filtrate reducer for the drilling fluid. The product filtrate reducer obtained by the preparation method has relatively high high-temperature resistance and salt resistance and good anti-collapse performance, can be used for greatly lowering the filtrate loss while being added into the drilling fluid, and capable of forming a firm, thin and compact mud cake, so that an oil-gas reservoir is not polluted by the drilling fluid to achieve effects of protecting the oil-gas reservoir.

Description

technical field [0001] The invention relates to a fluid loss reducer and a preparation method thereof, belonging to the technical field of oilfield chemical drilling fluid treatment agents, in particular to a high temperature, salt, anti-slump, anti-slump and fluid loss reducer for drilling fluid and a preparation method thereof. Background technique [0002] With the continuous development of oil and gas exploration and development, with the increasing difficulty of drilling, drilling fluids are also facing more and more difficulties. Under the test of complex conditions, the strata in the mud shale section are extremely easy to absorb water and peel off, causing collapse and block loss. Drilling fluid treatment agents are prone to chemical changes such as degradation and cross-linking under high temperature operations. The performance of drilling fluid will change after being eroded and polluted. The rheological properties are poor, the solid phase content is high, and the...

AI Technical Summary

Problems solved by technology

Since the 1970s, with the development of the "three sulfonate" drilling fluid system, sulfonated phenolic resin has been used as the most commonly used drilling fluid fluid loss control agent. This product has stable performance and has been produced on a large scale. However, the salt resistance Poor, large dosage, easy to produce a lot of air bubbles when used in high temperature deep wells

The patent with the publication number CN102533231A discloses a fluid loss reducer for ultra-high temperature drilling, which consists of 15-25 parts by weight of phenol, 30-40 parts by weight of formaldehyde, 6-10 parts by weight of sodium pyrosulfite, and 10-15 parts by weight of sodium sulfite , 15-20 parts by weight of water, 0.5-1 parts by weight of sodium hydroxide and 6-10 parts by weight of silicic acid to prepare the fluid loss control agent, the fluid loss control agent prepared by this method has an unsatisfactory suppression and anti-slump effect, and is resistant to salt , Calcium deficiency

The patent with publication number CN10173580A discloses a preparation method of high temperature and salt resistant drilling fluid fluid loss reducer, by dissolving vinyl monomer in water, adding initiator and aluminum citrate, and mixing at 40-100°C React for 1-4 hours to get the fluid loss control agent for drilling fluid. The fluid loss control agent for drilling fluid prepared by this method will undergo chemical degradation after high temperature and long-term application. The performance is not stable enough, and the anti-slump ability is insufficient. difficulty

The patent whose publication number is CN101851491A discloses a preparation method of fluid loss control agent for drilling fluid, which comprises 30-35 parts by weight of potassium humate, 20-30 parts by weight of etherified starch, and 10-15 parts by weight of hydroxyethyl cellulose element, 5-10 parts by weight of polyacrylamide and 5-10 parts by weight of water-soluble silicone oil, at a temperature of 120 ° C, a pressure of 0.8-1.2 MPa, and a constant temperature of 8-10 hours to obtain a semi-finished product, and then dried and crushed to add 5-10 The fluid loss reducer is prepared by compounding sulfonated asphalt in parts by weight. This method is complicated in process and high in energy consumption, and is not suitable for large-scale industrial production. Moreover, the compounded sulfonated asphalt will cause the drilling fluid to have a high fluorescence level, which will affect mud logging.