Apparatus and method for heating of hydrocarbon deposits by RF driven coaxial sleeve

An apparatus for heating hydrocarbon material in a subsurface formation from a wellbore comprising:

• an RF power source;
• a transmission section coupled to said RF power source;
• a transition section coupled to said transmission section;
• and
• a radiation section coupled to said transition section and comprising
• a first conductive element having first and second ends, and a connection location therebetween,
• a first conductive sleeve surrounding said first conductive element between the first end and the connection location thereof and so that said first conductive element extends outwardly beyond said first conductive sleeve,
• a conductive connection conductively joining said first conductive sleeve to said first conductive element at the connection location, and
• said RF power source providing RF current so that said first conductive element and said first conductive sleeve are configured as a dipole antenna for inducing electromagnetic near field heating of the surrounding subsurface formation.

A method for heating hydrocarbon material in a subsurface formation from a wellbore comprising:

• positioning a first conductive element in the subsurface formation, the first conductive element having first and second ends, and a connection location therebetween;
• providing a first conductive sleeve surrounding the first conductive element between the first end and the connection location thereof and so that the first conductive element extends outwardly beyond the first conductive sleeve;
• providing a conductive connection conductively joining the first conductive sleeve to the first conductive element at the connection location;
• and
• operating an RF power source coupled to the first conductive element and the first conductive sleeve to provide RF current therethrough so that the first conductive element and the first conductive sleeve are configured as a dipole antenna for inducing electromagnetic near field heating of the surrounding subsurface formation.