Method for improving oil recovery efficiency of medium and high-permeability reservoirs

A high-permeability, recovery rate technology, applied in the fields of fluid production, earth-moving drilling, wellbore/well components, etc., can solve the problems affecting the degree of recovery of the test block, waste of polymers and biosurfactants, etc. Achieve the effect of improving the field test effect, improving the water flooding efficiency, and widening the reservoir range

Active Publication Date: 2016-07-06
大庆三采技术有限公司
View PDF8 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method injects polymer and surfactant in the test block by injecting all water wells at the same time, and different water wells correspond to oil layers with different permeability. On the one hand, it will cause waste of polymer and biosurfactant, on the other hand, it will greatly affect the overall recovery degree of the test block

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

[0029] In block A of an oilfield, the reservoir temperature is 63°C, the reservoir pressure is 15.2MPa, the porosity is 34.2%, and the pore volume is 7.5×10 4 m 3 , permeability 2500×10 -3 μm 2 , geological reserves 3.2×10 4 t, the viscosity of surface crude oil is 976mPa.s, the salinity of formation water is 12350mg / L, the average water content of the block before the test is 97.2%, there are 12 oil wells and 6 water wells, and the daily water injection volume of water wells is shown in Table 1. Utilize method of the present invention to implement field oil displacement test in block A, concrete implementation steps are as follows:

[0030] Table 1 Daily water volume of well A in Block A, m 3

[0031] serial number

hashtag

Daily water injection

ranking

1

A 1

85

4

2

A 2

120

1

3

A 3

65

5

4

A 4

50

6

5

A 5

110

2

6

A 6

95

3

[0032] (...

Embodiment 2

[0045] In block B of an oilfield, the reservoir temperature is 75°C, the reservoir pressure is 10.5MPa, the porosity is 37.7%, and the pore volume is 9.2×10 4 m 3 , permeability 2100×10 -3 μm 2 , geological reserves 5.0×10 4 t, the viscosity of surface crude oil is 875mPa.s, the salinity of formation water is 9850mg / L, the average water content of the block before the test is 98.3%, there are 8 oil wells and 5 water wells, and the daily water injection volume of water wells is shown in Table 2. Utilize method of the present invention to implement field oil displacement test in block B, concrete implementation steps are as follows:

[0046] Table 2 Daily water volume of wells in Block B, m 3

[0047] serial number

hashtag

Daily water injection

ranking

1

B 1

75

5

2

B 2

130

1

3

B 3

110

2

4

B 4

90

3

5

B 5

85

4

[0048] (1) Reservoir screening

[0049] ...

Embodiment 3

[0061] In block C of an oilfield, the reservoir temperature is 58°C, the reservoir pressure is 13.5MPa, the porosity is 39.7%, and the pore volume is 5.0×10 4 m 3 , permeability 2800×10 -3 μm 2 , geological reserves 2.5×10 4 t, the viscosity of surface crude oil is 685mPa.s, the salinity of formation water is 5860mg / L, the average water content of the block before the test is 95.8%, there are 15 oil wells and 7 water wells, and the daily water injection volume of water wells is shown in Table 3. Utilize method of the present invention to implement field oil displacement test in block C, concrete implementation steps are as follows:

[0062] Table 3 Daily water volume of well C in Block C, m 3

[0063] serial number

hashtag

Daily water injection

ranking

1

C 1

125

1

2

C 2

70

6

3

C 3

65

7

4

C 4

120

2

5

C 5

105

3

6

C 6

90

4

7

C 7 ...

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 invention belongs to the technical field of tertiary oil recovery and particularly relates to a method for improving the oil recovery efficiency of medium and high-permeability reservoirs. The method specifically comprises the following steps of screening of oil reservoirs, determination of a polymer injection well and a surfactant injection well in a target oil reservoir, the polymer injection stage, the surfactant injection stage, the normal water injection stage and the field test effect evaluation stage. The method has the characteristics that the investment cost is low and the oil recovery efficiency is improved greatly through field tests. The field tests improve the oil recovery efficiency by more than 15%. The input-output ratio is greater than 1:5. The method has the characteristics of being simple in process and high in pertinence and operability. Thus, the method can be widely applied to the field tests for improving the oil recovery efficiency of the medium and high-permeability reservoirs.

Description

technical field [0001] The invention belongs to the technical field of tertiary oil recovery, and in particular relates to a method for increasing the recovery rate of crude oil in medium-high permeability oil reservoirs. Background technique [0002] With the rapid development of my country's economy, the demand for oil is increasing day by day, and the shortage of oil is becoming more and more serious. At present, the recovery of crude oil in my country is less than 40%, and the remaining recoverable oil reserves are huge, especially in medium and high permeability oil reservoirs. According to statistics, medium and high permeability reservoir resources account for more than 60% of the total resources. After long-term water flooding development, medium and high permeability reservoirs have reached the middle and late stages of the high water cut period, and the production decline is serious, and it is difficult to stabilize production. Therefore, new improvements are urgentl...

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): E21B43/22E21B43/16E21B43/20
CPCE21B43/16E21B43/164E21B43/20
Inventor 刘琴
Owner 大庆三采技术有限公司
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