Profile control and displacement system and oil displacement method suitable for carbonate weathered crust reservoir

A weathering shell and carbonate technology, applied in chemical instruments and methods, drilling compositions, etc., can solve the problems of poor stability of the two-phase interface, poor dispersion and stability, inability to stabilize adsorption, etc. Dispersion stability can be improved and the effect of increasing the sweep volume

Active Publication Date: 2019-01-22
CHINA UNIV OF PETROLEUM (EAST CHINA)
View PDF7 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the poor dispersibility and stability of ordinary pure nanomaterial systems under high salinity and temperature conditions in reservoirs, especially in heterogeneous reservoirs such as fractures, stable adsor

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Profile control and displacement system and oil displacement method suitable for carbonate weathered crust reservoir
  • Profile control and displacement system and oil displacement method suitable for carbonate weathered crust reservoir

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0043] A method for preparing a control and flooding system suitable for carbonate weathering crust reservoirs, comprising the following steps:

[0044] At room temperature (20±5°C), first add nano-silica to water, stir for 3-5 minutes and then ultrasonically 60-70 minutes to disperse nano-silica in water; then add quaternary ammonium salt surfactant, stir The surfactant is fully dissolved in 3-5 minutes to obtain a control and flooding system suitable for carbonate weathering crust deposits.

[0045] An oil displacement method suitable for carbonate weathering crust reservoirs. When the water content of the oil well corresponding to the water injection well increases significantly, the water flooding is inefficient or ineffective and the development effect becomes poor, and a large amount of remaining oil remains in the formation, the described method is adopted. The control and flooding system suitable for carbonate weathering crust reservoirs is used for oil displacement, i...

Embodiment 1

[0058] This example evaluates the high-temperature and high-salt emulsification performance of the control and flooding system suitable for carbonate weathering crust reservoirs.

[0059] At room temperature (20±5°C), configure 10 mL of a composite system solution with a mass fraction of nano-silica of 2.0%, quaternary ammonium salt surfactants of different mass fractions, and water as the balance. The surfactant has formula 1 The structure shown:

[0060] Formula 1

[0061] In formula 1, R is C 10 h 21 The linear carbon chain, n is 1.

[0062] The water is treated oilfield reinjection sewage, the pH value is 5.6, the total salinity is 20 000 mg / L, ρ 油 悬浮物 <30mg / L.

[0063] The mass fractions of the surfactants are 0.03%, 0.06%, 0.1%, 0.25%, 0.5%, 0.75%, and 1%, respectively.

[0064] The above solution was mixed with 10 mL of n-dodecane at a volume ratio of 1:1 and put into a glass bottle, and stirred continuously at a speed of 10,000 r / min for 4 min by a high-speed h...

Embodiment 2

[0066] At room temperature (20±5°C), configure a composite system in which the mass fraction of nano-silica is 2.0%, the mass fraction of quaternary ammonium salt surfactant ranges from 0.02% to 1.0%, and the balance is water. The trend of the interfacial tension of the composite system changing with the mass fraction of surfactant was determined. Described tensio-active agent has the structure shown in formula 1:

[0067] Formula 1

[0068] In formula 1, R is C 12 h 25 The linear carbon chain, n is 2.

[0069] The water is treated oilfield reinjection sewage, the pH value is 6.7, the total salinity is 45 000 mg / L, ρ 油 悬浮物 <50mg / L.

[0070] Such as figure 2 Shown, the abscissa is the concentration of surfactant, and the ordinate is the surface tension, which is measured by the ring method. It can be seen that when the mass fraction of quaternary ammonium salt surfactant is greater than 0.5%, the interfacial tension of the system no longer decreases.

[0071] Based o...

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

PropertyMeasurementUnit
Particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a profile control and displacement system suitable for a carbonate weathered crust reservoir. The system comprises, by mass, 0.5-2% of nano-silica, 0.01-3.0% of a quaternary ammonium salt surfactant, and the balance of water. The invention also discloses a preparation method of the system. The preparation method comprises the following steps: adding the nano-silica into water at room temperature, performing stirring, and carrying out ultrasonic treatment to achieve uniform dispersion in water; and adding the quaternary ammonium salt surfactant, and performing stirring to fully dissolve the surfactant in order to obtain the system. The profile control and displacement system adopting the quaternary ammonium salt surfactant and the easily available silica nano-material has the advantages of certain decompression and augmented injection effect, good stability, good stratum injectivity, good interface stabilizing ability and good emulsification performance, plays arole in oil displacement, and also can be used for the profile control of the stratum.

Description

technical field [0001] The invention relates to the technical field of petroleum exploitation, in particular to a control and displacement system and an oil displacement method suitable for carbonate weathering crust reservoirs. Background technique [0002] At present, carbonate weathering crust oil reservoirs are widely developed in marine oil and gas basins all over the world. According to statistics (2009), the weathered crust type accounts for 22% of the 202 carbonate oil and gas fields in the world. my country also has a number of high-quality large weathered crust oil and gas fields, such as the Renqiu Oilfield in the Bohai Bay Basin, the Tahe Oilfield and Lunnan Oilfield in the Tarim Basin, and the Jingbian (Changqing) Gas Field in the Ordos Basin. The characteristic of carbonate weathering crust reservoirs is that the extensive development of weathering crusts provides important oil and gas migration pathways and storage spaces. However, due to the difference in t...

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
IPC IPC(8): C09K8/58C09K8/584
CPCC09K8/58C09K8/584C09K2208/10
Inventor 赵明伟戴彩丽吴一宁孙永鹏赵光李琳
Owner CHINA UNIV OF PETROLEUM (EAST CHINA)
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