Novel coring and paraffin-removing method for coiled tubing in low-pressure low-yield oil-gas well

Abstract

The invention provides a novel coring and paraffin-removing method for coiled tubing in a low-pressure low-yield oil-gas well. The method includes the steps of modifying the tail end of the coiled tubing into a coring tool in the form of a 45 degrees angled nib; connecting parts, slowly putting the coiled tubing and the coring tool in the well, and performing coring and paraffin removal; observing interior pressure of the coiled tubing, and if the interior pressure is stable, slowly lifting up the coiled tubing and the coring tool to the surface; after lifting the coiled tubing and the coring tool to the surface, building the pressure with an alcohol injection pump or through residual pressure in the coiled tubing, and collecting a paraffin core. According to the technical features of mechanical paraffin removal and chemical paraffin removal and to the principle of drilling coring, the coring and wax-removing method combining paraffin remover injection by pumping and the coiled tubing is used; the problem that paraffin blockage under low pressure and low yield is better solved, the blocking paraffin in the tubing is cleared, a paraffin-removing profile of a shaft is established, and following production of the oil-gas well is better guided.

Description

technical field [0001] The invention relates to the technical field of oil and natural gas exploitation, in particular to a new wax-removing method for coiled tubing coring of oil and gas wells with low pressure and low production. Background technique [0002] At present, the coiled tubing wax removal technology adopted in domestic wax-deposited oil wells is mainly to establish a liquid (hot water, hot oil, wax remover) circulation channel in the oil and gas well production string through coiled tubing, and then continuously transfer the liquid through circulating heating. The high-temperature heat carried is transferred to the upper end surface of the plugged section in the production string, melting the solidified wax in the production string and returning to the ground with the crude oil or air flow, deepening the coiled tubing while circulating, and finally releasing the plugging in the string. clogged. Although this method better protects the oil and gas well reservoi...

AI Technical Summary

Problems solved by technology

Although this method better protects the oil and gas well reservoir, it is not suitable for low pressure and low production oil and gas wells. It cannot use the energy of the oil and gas well itself to bring out the wax after circulating the liquid and melting the high temperature heat, and the wax removal effect is poor.

At the same time, it cannot well establish the wellbore wax plugging profile, which brings certain difficulties to the follow-up research work of wax removal and prevention.

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