Method for removing filtercake

A method for removing filtercake from a subterranean borehole, comprising:

• drilling the borehole with a drilling fluid to form a filtercake comprising an oxidation degradable component and an activating agent for activating a precursor of an oxidizing agent, wherein the filtercake is free of the precursor;
• contacting the filtercake with a fluid containing the precursor of the oxidizing agent, wherein the precursor is soluble in the fluid, stable at ambient temperature and thermally activatable at the downhole temperature of the filtercake to form the oxidizing agent;
• allowing the precursor to remain in contact with the filtercake to form the oxidizing component to degrade the oxidation degradable agent and decompose the filtercake;
• flushing away the decomposed filtercake.

A method for removing filtercake from a subterranean borehole, comprising:

• drilling the borehole with a drilling fluid to form a filtercake comprising an oxidation degradable component and an activating agent comprising a tertiary amine for activating an organic hydroperoxide;
• thereafter contacting the filtercake with a fluid containing a solution of the organic hydroperoxide;
• allowing the organic hydroperoxide to remain at the downhole temperature in contact with the activating agent in the filtercake for a period of time effective to form an oxidizing agent to degrade the oxidation degradable component and decompose the filtercake;
• flushing away the decomposed filtercake.

A method for removing filtercake from a subterranean borehole, comprising:

• drilling the borehole with a drilling fluid to form a filtercake comprising an oxidation degradable component and an activating agent for activating an organic hydroperoxide;
• flushing over the filtercake with an additional activating agent comprising a metal salt solution wherein the metal is selected from the group consisting of copper, cobalt, nickel, chromium, iron and combinations thereof;
• thereafter contacting the filtercake with a fluid containing a solution of the organic hydroperoxide;
• allowing the organic hydroperoxide to remain at the downhole temperature in contact with the activating agents in the filtercake for a period of time effective to form an oxidizing agent to degrade the oxidation degradable component and decompose the filtercake;
• flushing away the decomposed filtercake.

A method for removing filtercake from a subterranean borehole, comprising the steps of:

• drilling the borehole with a drilling fluid to form a filtercake comprising an oxidation degradable component and an activating agent for activating a precursor of an oxidizing agent, wherein the filtercake is essentially free of the precursor;
• installing gravel pack screens and tool assemblies into the borehole;
• determining fluid losses;
• adding sand in a non-viscosified carrier to the borehole
• after the screen installation step, contacting the filtercake with the precursor of the oxidizing agent;
• allowing the precursor to remain in contact with the filtercake for a period of time effective to form the oxidizing agent to degrade the oxidation degradable component and decompose the filtercake;
• flushing away the decomposed filtercake.

A method for removing filtercake from a subterranean borehole, comprising:

• drilling the borehole with a drilling fluid to form a filtercake comprising an oxidation degradable component and an activating agent comprising a tertiary amine for activating a precursor of an oxidizing agent, wherein the filtercake is essentially free of the precursor;
• contacting the filtercake with the precursor of the oxidizing agent;
• allowing the precursor to remain in contact with the filtercake to be activated by the tertiary amine and form the oxidizing agent to degrade the oxidation degradable component and decompose the filtercake;
• flushing away the decomposed filtercake.