NOVELTY - An oilfield associated gas ethane recovery system has a preprocessing raw material gas pressurizing unit provided with five stage centrifugal compressors to remove water in gas and other impurities. Raw gas enters the raw material gas dewatering unit for dehydration to separate condensate liquid. The liquid is separated, demethanized and returned to the sewage. The gas is pressurized and dehydrated in the low temperature fractionation unit. The liquid hydro carbon is subjected to heating. The pressure is changed in a cooling box with the raw material gas exchanging heat to obtain a product.    USE - Oilfield associated gas ethane recovery system.    ADVANTAGE - The oilfield associated gas ethane recovery system ensures the yield and saves the energy reference value.    DETAILED DESCRIPTION - An oilfield associated gas ethane recovery system has a raw material gas pressurizing unit, a raw material gas dewatering unit and a low temperature fractionation unit. The preprocessing raw material gas pressurizing unit is provided with five stage centrifugal compressors (C0101-C0105) with a two stage centrifugal compressor, where the raw material gas is provided to remove water in gas and the other impurities to reach the final pressure 5.1. Raw gas enters the raw material gas dewatering unit to dehydrate and a drying medium. The gas is pressurized and the gas temperature is maintained at 38 degrees c. A condensate liquid is separated by raw material separators (D0102-D0105). The heavy hydrocarbon and water are separated and entered into a demethanizer 8 layer tower plate. The gas is pressurized and dehydrated at 37. 85.14MPa by a plate-fin heat exchanger (E0301) at 25 degrees c and the temperature is reduced by another raw material separator (D0301) and cooled at 57 degrees c. The pressure is changed into 0.435Mpa at the plate-fin heat exchanger with the raw material gas exchanging heat at 22.67 degrees c to obtain a product.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of an oilfield associated gas ethane recovery system.'(Drawing includes non-English language text)'    Five-stage centrifugal compressors (C0101-C0105)    Raw material separators (D0101-D0105)    Low temperature separator (D0301)    Plate-fin heat exchangers (E0101-E0105)    Cooling boxes (E0301, E0302)