Preparation method of tackifier for drilling fluid

Abstract

The invention discloses a preparation method of a tackifier for a drilling fluid. The method comprises the following steps of: adding 71 kg of acrylamide and 700 kg of water into a polymerizing kettle, preparing a 20 percent acrylamide aqueous solution, adding 0.1 kg of initiator after a certain period of time, and reacting at constant temperature for a certain period of time to obtain gel polyacrylamide; taking the gel polyacrylamide out, pelletizing, and preparing into 2 percent polyacrylamide aqueous solution; adjusting the pH of a system to 11 with a sodium hydroxide solution, adding 85 kg of formaldehyde and 100 kg of sodium bisulfite aqueous solution, and reacting with stirring for a certain period of time to obtain sulfomethylated polyacrylamide gel; precipitating and separating reactants with 95 percent ethanol, and recycling and distilling an ethanol aqueous solution for circular use; and taking a precipitated polymer, removing ethanol, drying in vacuum and crushing to obtain a product. The tackifier has large tackifying and flow pattern adjusting capabilities, and can be used for keeping the viscosity of the drilling fluid under severe conditions such as high temperature, high salinity, high calcium-magnesium ions and the like.

Description

technical field [0001] The invention relates to a preparation method of a viscosifier for drilling fluid. Background technique [0002] In oil drilling, due to the increase of well depth, the bottom of the well is under high temperature and high pressure conditions, the drilling section is long and there are large sections of open holes, and many complex formations must be drilled, so the operating conditions are much harsher than ordinary wells, so Higher requirements are also placed on the performance of drilling fluids. Under high temperature conditions, various components in the drilling fluid will undergo changes such as degradation, fermentation, thickening and failure, which will cause drastic changes in the performance of the drilling fluid, and it is difficult to adjust and control; and with high formation pressure, The drilling fluid must have a high density, resulting in a high solid content in the drilling fluid. In this case, the possibility of downhole comple...

AI Technical Summary

Problems solved by technology

Under high temperature conditions, various components in the drilling fluid will undergo changes such as degradation, fermentation, thickening and failure, which will cause drastic changes in the performance of the drilling fluid, and it is difficult to adjust and control; and with high formation pressure, The drilling fluid must have a high density, resulting in a high solids content in the drilling fluid

In this case, the possibility of downhole complex situations such as differential pressure sticking, lost circulation, and blowout will greatly increase, and it will be more difficult to maintain good rheology and low loss of drilling fluid. At this time, conventional drilling Fluid can no longer meet the requirements of drilling engineering