A kind of natural gas development adopts bubble discharge drag reduction system

Abstract

The invention discloses an efficient foam scrubbing drag reducing system for natural gas exploitation. The efficient foam scrubbing drag reducing system comprises a foaming agent and a drag reducing agent, the foaming agent is selected from sodium dodecyl sulfate with the molecular formula as C12H15SO3Na, and an acrylamide monomer, a 2-acrylamide-2-methylpropanesulfonic acid monomer and an MJ-16 hydrophobic monomer are polymerized into a hydrophobic association polymer, and the polymer is hydrolyzed to form the drag reducing agent. The efficient foam scrubbing drag reducing system is capable of effectively reducing friction drag between bubbles and the air pipe inner wall as well as between water and the air pipe inner wall and effectively improving foam scrubbing and gas exploitation effect. Meanwhile, the system is resistant to high temperature and salt, the temperature resistant index reaches 140 DEG C, the NaCl resisting concentration reaches 30%, and the CaCl2 resisting concentration reaches 20%. The raw materials are simple and easy to obtain, and the efficient foam scrubbing drag reducing system is easy to prepare, low in production cost and worthy of effective popularization.

Description

technical field [0001] The invention relates to a high-efficiency foam discharge drag reduction system for natural gas well development, and belongs to the technical field of chemical additives for oil and gas fields. Background technique [0002] In the process of natural gas exploitation, due to the existence of groundwater, water will enter the wellbore through fractures during exploitation, making it difficult to extract natural gas. Problems such as liquid accumulation and water production affecting the normal production of gas wells have gradually emerged. Gas well production has transformed single-phase gas seepage into gas-water two-phase seepage, which not only reduces the gas phase permeability, but also consumes a large amount of formation energy, and the liquid accumulation that cannot be carried in the wellbore reduces production. Pressure difference, resulting in low production or even shutdown of gas wells, water production and wellbore fluid accumulation of g...

AI Technical Summary

Problems solved by technology

In the bubble discharge process, when the air bubbles and water are lifted out of the wellbore, they will constantly rub against the inner wall of the air pipe, resulting in a slow lifting speed of the air bubbles with water, and at the same time, the bubbles will rupture during the continuous shearing process, reducing the bubble discharge. Effect

In this way, the foaming performance and foam stabilizing performance of the surfactant are required to be very good, so as to achieve a good foam discharge effect, but this greatly increases the requirements of the surfactant, and increases the development and use costs of the surfactant.

At the same time, due to the deep burial of the gas reservoir, the high temperature at the bottom of the well, and the high salinity of the formation water, the bottom fluid generally has the characteristics of high temperature and high salt, and it is difficult for ordinary surfactants to exert a good drainage effect.

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