Unlock instant, AI-driven research and patent intelligence for your innovation.

Wet type combustion huff-puff oil extraction method

A fire huff and puff, wet technology, applied in the field of oil extraction from wells, can solve the problems of high heat loss, reduced heat utilization rate and sweep efficiency, and high temperature damage to the pipe string.

Active Publication Date: 2015-05-13
CHINA UNIV OF PETROLEUM (BEIJING)
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the main problems of the steam injection thermal oil recovery method are: first, the heat loss of the surface and the wellbore is high (up to 10-30%); second, the oil-water two-phase flow after steam condensation will affect the production of heavy oil, and the Hot water will absorb a lot of heat; third, steam phase separation and steam overlay at the bottom of the well and in the formation will reduce heat utilization and sweep efficiency; fourth, it is not suitable for deep, offshore, desert and strong water-sensitive reservoirs; fifth, In the middle and late stage of mining, the output is low, the oil-gas ratio is low, and the economic benefit is poor, so it is necessary to switch the development method
The technology for the recovery of heavy oil by fire huff and puff described in this patent does not mention the process of drilling the well before ignition, but if the well is not opened, it is easy to cause uneven ignition, and there is a risk of explosion and tempering in the wellbore; in addition, the patent proposes In the process, it is necessary to stop the ignition and start the well production (water injection) after the well is soaked. The water injection refers to the water injection of the water injection well to drive the oil, and no water injection during or after the air (oxygen-enriched) injection, In this way, when the fire huff and puff production is carried out, the oil well is in a high temperature environment during the soaking and oil production period, and the oil well string is prone to high temperature damage, and the temperature of the produced fluid is too high

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
  • Wet type combustion huff-puff oil extraction method
  • Wet type combustion huff-puff oil extraction method
  • Wet type combustion huff-puff oil extraction method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0116] see figure 1 . This example is aimed at a single-layer heavy oil reservoir, a deep ordinary heavy oil reservoir with a size of 600m×200m×20m in the Nanpu reservoir of Bohai Sea, the top depth of the reservoir is 1000m, the thickness is 20m, and one horizontal well section is long For the 300m horizontal well, the specific reservoir parameters and well parameters are shown in Table 1. A homogeneous reservoir geological model with 20 × 40 × 20 grids was established, and the thermal recovery simulator of ECLIPSE was used to simulate and calculate the production effect of three rounds of wet combustion huff and puff recovery in horizontal wells. The production effect of 3 rounds of steam huff and puff in horizontal well and 3 rounds of dry fire huff and puff in horizontal well. Horizontal wells are completed with casing.

[0117] After washing and clearing the crude oil in the wellbore of horizontal well 4, inject oxidant 10 into oil layer 1 with air as oxidant, pass 1,0...

Embodiment 2

[0143] refer to figure 2 , figure 2 It is a schematic diagram of the vertical well wet combustion huff and puff recovery method. figure 2 Among them, 1 is oil reservoir, 2 is overburden, 3 is underburden, 4' is vertical well, 5 is burned area, 6 is combustion front, 7 is cracking and evaporation area, 8 is condensation heating area, and 9 is Gas-swept area, 10 is injected oxidant, 11 is injected water.

[0144] In this embodiment, after the crude oil in the vertical well 4 is cleaned out, the oxidant 10 is injected into the oil layer 1, and at the same time, the 30KW electric heater is heated to 400°C to ignite, so that part of the crude oil components are burned in the high-pressure oxidizer 10. As the oxidant 10 is continuously injected, the combustion front 6 propagates from the oil well 4 to the deep part of the oil reservoir 1 . When the high temperature of the combustion front 6 partially cracks the crude oil in the front cracking evaporation zone 7, and vaporizes ...

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 provides a wet type combustion huff-puff oil extraction method, comprising the steps of: 1, flushing an oil well, then injecting an oxidizing agent into an oil deposit, igniting to burn coke-like components generated by the oxidization and splitting decomposition of crude oil in the oil deposit to heat an oil layer; 2, while the oxidizing agent is completed injected or is injecting, injecting water to reduce the high temperature of a near wellbore formation, and extracting oil after soaking the well for 3-10 days; 3, after extracting oil for 100-700 days, performing a next round of processes of injecting the oxidizing agent, igniting, injecting water, soaking and extracting oil. According to the method provided by the invention, the water is injected into the oil deposit after the oxidizing agent is injected, and water flow flows through a combusted area and carries heat to the deep part of the oil deposit, so that the heating range of the oil deposit is enlarged, and the peripheral temperature of the oil well is prevented from being too high. According to the wet type combustion huff-puff oil extraction method, formation water and the injected water are vaporized to generate steam, heat, smoke and steam generated by combustion are comprehensively utilized to recover in a combined manner, the output and the recovery efficiency of the crude oil are improved, and the recovery efficiency is up to more than 70%.

Description

technical field [0001] The invention belongs to the field of oil extraction from wells, and in particular relates to an oil extraction method using thermal energy. Background technique [0002] The resources of heavy oil and tar sands are abundant in the world, and the reserves are more than three times that of conventional oil resources. my country's heavy oil reserves are estimated to exceed 20 billion tons, accounting for more than 20% of the total oil and gas reserves, and the degree of production is relatively low. As the recoverable reserves of conventional oil continue to decrease, the probability of newly discovering large oil fields becomes smaller, and heavy oil and tar sands will be one of the main oil and gas resources in the future. However, heavy oil contains high colloid and asphaltene content, viscosity of tens to hundreds of thousands of mPa·s, and poor fluidity. Water flooding, chemical flooding, and gas flooding cannot be recovered or the recovery effect ...

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 Patents(China)
IPC IPC(8): E21B43/243
Inventor 钟立国于镝王彦超张守军陆福刚薛瑞新宫宇宁
Owner CHINA UNIV OF PETROLEUM (BEIJING)