(under subclass 302) A process in which a heated fluid is introduced into the pores of the earth, said fluid being heated before it enters the pores of the earth.
SEE OR SEARCH THIS CLASS, SUBCLASS:
247, for a process for using nuclear energy to heat a fluid to be injected into the formation.
272.1, for a process involving input and output wells and including placing preheated fluid into the formation.
288, for a process involving placing a heated cementing, plugging or consolidating material in the pores of the earth.
SEE OR SEARCH CLASS 299, Mining or In Situ Disintegration of Hard Material,
3+, for mining by introducing a heated fluid into the formation. See the reference to Class 299 in section V of the class definition of Class 166 for the line between Class 166 and Class 299.
