Polymer displaced steam injecting hot oil deposit exploiting method

A steam injection and oil reservoir technology, applied in the direction of production fluid, earthwork drilling, wellbore/well components, etc., can solve the problems that thermal recovery cannot be applied

Inactive Publication Date: 2004-04-07
PETROCHINA CO LTD
View PDF0 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For oil layers with a crude oil viscosity lower than 30mPa.s under oil layer conditions, especially oil fields with large reserves, the above-mentioned polymer flooding water injection development method is usually used. Due to production costs and technical reasons, thermal recovery cannot be applied

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] The buried depth of the oil reservoir in oilfield 1 is 1000m, the effective thickness of the oil layer is 13.0m, the net total thickness ratio is 0.5, the average porosity is 24.0%, the average permeability is 200md, the permeability variation coefficient is 0.7, and the crude oil viscosity under the oil layer conditions is 4.5mPa. s. At present, the oil field adopts polymer injection, and the water cut is relatively high, and the degree of staged recovery reaches about 50.0%.

[0029] 1) Carry out rough screening according to the geological characteristics of the reservoir, crude oil properties and development status. The reservoir meets the following conditions: reservoir depth 0.30, total reservoir thickness > 5.0m, net-to-total thickness ratio > 0.3, reservoir porosity > 0.15, permeability variation coefficient < 0.8.

[0030] 2) Choose the reverse 7-point well pattern, and use the newly drilled well as the steam injection well, with the well spacing between the i...

Embodiment 2

[0035] The buried depth of oil field 2 is 300-500m, the effective thickness of the oil layer is 21.0m, the ratio of net total thickness is 0.46, the average porosity is 20%, the average permeability is 200md, the coefficient of variation of permeability is 0.65, and the viscosity of crude oil under the condition of oil layer is 10 -30mPa.s, the original geological reserves are 130 million tons. At present, the oil field adopts polymer injection, and the water cut is relatively high, and the degree of staged recovery reaches about 40.0%.

[0036] 1) Carry out rough screening according to the geological characteristics and development status of the oilfield. The reservoir meets the following conditions: reservoir depth 0.30, total reservoir thickness > 5.0m, net-to-total thickness ratio > 0.3, reservoir porosity > 0.15, permeability variation coefficient < 0.8.

[0037] 2) Select the reverse 5-point well pattern, and use the newly drilled wells as steam injection wells, and th...

Embodiment 3

[0041] The buried depth of oilfield 3 reservoir is 1600m, the effective thickness of oil layer is 21.0m, the ratio of net to total thickness is 0.56, the average porosity is 20%, the average permeability is 200md, the coefficient of variation of permeability is 0.60, and the viscosity of crude oil under oil layer conditions is 4-8mPa .s, the original geological reserves are 230 million tons. At present, the oil field adopts polymer injection, and the water cut is relatively high, and the degree of staged recovery reaches about 45.0%.

[0042] 1) Carry out rough screening according to the geological characteristics and development status of the oilfield. The reservoir meets the following conditions: reservoir depth 0.30, total reservoir thickness > 5.0m, net-to-total thickness ratio > 0.3, reservoir porosity > 0.15, permeability variation coefficient < 0.8.

[0043] 2) Select the reverse 9-point well pattern, and use the newly drilled wells as steam injection wells, and the w...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The polymer displaced steam injecting hot oil deposit exploiting method is used for further exploitation of polymer displaced oil deposit to raise the exploiting rate. The polymer displaced oil deposit is converted into hot steam soak and hot steam displacement through the step of: selecting oil deposit with oil layer depth smaller than 3000 m, residual oil saturation degree greater than 0.30. oil depth thickness greater than 5.0 m, net total thickness ratio greater than 0.3, oil layer porosity greater than 0.15 and permeability variation coefficient smaller than 0.8; selecting reversed nine-point well network and drilling new steam injecting well apart from production well by 150-300 m for steam injecting hot exploitation; and converting into steam displacement of simultaneous steam injection and continuous production with single well steam injection speed of 1.0-3.0 cu m / d. ha m, well bottom steam quality greater than 30 % and injection-production ratio manufactured over 1.0. The present invention raises recovery ratio by over 10 %.

Description

[0001] Field [0002] The invention relates to oil extraction technology, which is a steam injection thermal recovery method for polymer flooding or oil reservoirs after polymer flooding to continue to exploit and improve the recovery rate. Background technique [0003] Polymer flooding is actually polymer water flooding, that is, dissolving polymer (usually polyacrylamide) in water, increasing the viscosity of injected water, and then injecting it into the oil reservoir. The viscosity of water reduces the oil-water mobility ratio, weakens viscous fingering, increases sweep coefficient, and thus improves recovery. Injection of the polymer begins with the injection of a slug of polymer solution, the slug is about 60% of the pore volume, and the polymer slug is displaced by the injected water. [0004] Polymer flooding can generally increase the recovery rate by about 10% on the basis of water flooding, and the total recovery rate of water flooding + polymer flooding can reach ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): E21B43/24
Inventor 张义堂计秉玉廖广志李秀娈石成方李莉沈德煌哈斯刘尚奇赵郭平张建刘誉松邱德友李晓玲
Owner PETROCHINA CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap