Casing gas decompression gas lift tubular column and using method thereof

The invention relates to oil field underground equipment, in particular to a casing gas decompression gas lift tubular column and a using method thereof. The casing gas decompression gas lift pipe column comprises a sucker rod, an oil pipe, a disjoint device, an upper sliding valve, a long plunger, an upper sealing cylinder, a lower sliding valve, a liquid and gas inlet valve, a lower sealing cylinder, a gas-liquid mixed pumping pump and a gas-liquid separator. The sucker rod is arranged in the oil pipe and is sequentially connected with the disjunction device, the gas-liquid mixed suction pump and the gas-liquid separator; the lower part of the long plunger is connected with the lower slide valve; the lower end of the upper sealing cylinder is connected with the lower sealing cylinder; a liquid inlet and air inlet valve is arranged at the joint of the upper sealing cylinder and the lower sealing cylinder. The casing gas pressure reduction gas lift tubular column is simple in structure and easy to install, th