Single stage filter cake removal of barite weighted water based drilling fluid

Based on the result of this work the filter cake removing formulation dissolved more than 90% of the filter cake formed by real barite drilling fluid in a single stage within 24 h. The removal formulation consists of high pH potassium base DTPA of 20 wt% concentration, enzyme as a polymer degrading agent, and one of the following converting/catalytic agents (potassium carbonate, potassium formate, or potassium chloride). The use of converting agents increased the barite solubility from 67-95%.