A drilling fluid viscosity reducer

Abstract

The invention discloses a novel efficient drilling fluid viscosity reducer. The novel efficient drilling fluid viscosity reducer is prepared by weighing and uniformly mixing the following raw materials by weight percent: 60-75% of copolymer, 10-20% of organosilicon potassium humate and 15-25% of A agent; the A agent is composed of the following components in parts by weight: 27-36 parts of low molecular weight polyacrylamide, 50-70 parts of sulfonated lignite, 3-8 parts of silane coupling agent, 2-5 parts of sodium hexametaphosphate, 1.5-3.2 parts of polyaspartic acid, 7-12 parts of acrylic acid and 7-12 parts of sodium allysulfonate. A net structure formed by a main body polymer and clay particles can be effectively broken up by the efficient drilling fluid viscosity reducer disclosed by the invention, the clay particles are enveloped due to intermolecular conclusion while the rheology of the drilling fluid is regulated and controlled; and therefore, the inhibiting ability o the system is not weakened but even enhanced, the solid phase content in the system is maintained, the shear dilution feature is good, and the Casson parameter is easy to control and regulate.

Description

technical field [0001] The invention relates to the field of raw materials for oil well drilling, in particular to a drilling fluid viscosity reducer. Background technique [0002] With the increase of world energy demand and the development of drilling technology, the number of deep wells and ultra-deep wells in my country is also increasing. During drilling, the deeper the wellbore, the higher the temperature inside the wellbore. Due to the automatic dispersion of clay particles in drilling fluid under high temperature conditions, the particle concentration increases and the specific surface area increases. The problem of high temperature thickening of drilling fluid becomes more and more prominent. The viscosity reducer is one of the indispensable drilling fluid treatment agents in the drilling process, and it plays a very important role in adjusting the rheology of the drilling fluid. [0003] As early as the end of the 1930s, people began to use inorganic phosphate to...

AI Technical Summary

Problems solved by technology

Afterwards, research mainly focused on anionic polymer viscosity reducers based on maleic anhydride (MA), sodium allylsulfonate (AS) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and zwitterionic polymer viscosity reducers with cationic groups, but the research is relatively small, especially in recent years, the research work in this area has almost stagnated, and the examples of successful application in the field are even rarer, and there is a lack of applicable Viscosity reducer under special conditions (such as ultra-high temperature, high density, etc.), which puts forward a new topic for the research of viscosity reducer