CHROME FREE WATER-BASED WELLBORE FLUID

摘要

Methods for maintaining the rheology and reducing the fluid loss of chrome- free, aqueous-based wellbore fluids under high temperature-high pressure conditions are disclosed. The method may comprise formulating the chrome-free, aqueous wellbore fluid with an aqueous base fluid, at least one chrome-free viscosifier, at least one chrome-free fluid loss control additive, at least one chrome-free dispersant; and circulating the chrome-free aqueous-based wellbore fluid in a wellbore at temperatures exceeding 300°F.