Tubular column for evenly injecting steam in SAGD (Steam Assisted Gravity Drainage) horizontal well and process

Abstract

The invention discloses a tubular column for evenly injecting steam in an SAGD (Steam Assisted Gravity Drainage) horizontal well and a process. The tubular column comprises a vacuum heat insulation pipe, a thermal compensation extension pipe and a steam injection pipe, the vacuum heat insulation pipe is connected with the thermal compensation extension pipe through the steam injection pipe, a backflushing packer is arranged at the front part of the steam injection pipe; one or more fracture-steam injection units are arranged at the middle part of the steam injection pipe, the fracture-steam injection unit comprises a fracture valve, a steam injection valve and a centering guide, the fracture-steam injection units are packed through a heat sensitive packer, and a backflushing valve is arranged at the tail end of the steam injection pipe. By applying the process of micro-fracturing evenly, backflushing the well, packing in a segmenting way, and injecting the steam in a segmenting way onthe steam injection horizontal well, the purpose of rapidly evenly injecting steam into a thickened oil reservoir stratum is fulfilled. The tubular column is suitable for the SAGD steam injection horizontal well with strong stratum heterogeneity and poor heat and mass transfer capacity.

Description

technical field [0001] The invention relates to a heavy oil well SAGD horizontal well steam injection technology, in particular to a SAGD horizontal well steam injection pipe string and a process. Background technique [0002] SAGD, referred to as Steam Assisted Gravity Drainage (Steam Assisted Gravity Drainage), is a cutting-edge technology for developing super heavy oil reservoirs. This technology is to deploy vertically stacked horizontal well pairs in the same oil reservoir, inject high-dryness steam from a horizontal well located in the upper part of the oil reservoir into the oil reservoir, contact the cold oil area, release the latent heat of vaporization to heat the crude oil, and be heated Crude oil with reduced viscosity and steam condensate flow downward under the action of gravity, and are produced from horizontal wells at the bottom of the reservoir, which is the most effective recovery method for heavy oil reservoirs. [0003] The key to the success of SAGD li...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a uniform steam injection pipe string and process for SAGD horizontal wells. The present invention can better solve the problem of low heating efficiency of steam injection in SAGD horizontal wells and long preheating time for heavy oil layers; and The uneven development of the steam cavity caused by the heterogeneity of the reservoir causes the problem of local steam channeling

Images