Abstract: Friction reducers, fracturing fluid compositions and methods for treating subterranean formations, wherein friction reducer is a reacted, grafted or blend of galactomannan gum and polyacrylamide having a molecular weight between from about 300,000 to about 30,000,000 and wherein the amount of polyacrylamide in the friction reducer is from about 15 to about 50 weight percent based on the total weight of the polyacrylamide and galactomannan gum.

Abstract: A method for recovering original type oil from a system that has been charged with an original type refrigerant eliminates the need for removing and cleaning individual components. A separate oil separator is connected to the compressor suction of the air conditioning system. The air conditioning system is operated to collect oil in the oil separator. Then the oil separator is bypassed and the system is injected with a replacement oil. The system is again operated, with the replacement oil mixing with the original type oil. The oil separator is again reconnected into the system at the suction port of the compressor. The air conditioning system operates again, with the oil being collected a second time. The system is then ready for recovery of refrigerant by a recovery unit.