On August 15, in Erlian Menglin Oilfield, Huabei Oilfield, 20 days after the "ignition" of three gas injection wells, the gas injection pressure, temperature, produced gas components and oil samples were recorded on site. The monitoring data shows that the results are in line with the prediction, indicating that the ignition is successful. This will open up a new path for the overall beneficial development of heavy oil reservoirs in Huabei Oilfield.
At present, the reserves of heavy oil reservoirs in Huabei Oilfield account for 5.7% of the total reserves. There are generally problems of low recoverable reserves and high remaining reserves by water flooding. Relying on water flooding has little potential to further enhance oil recovery, and it is urgent to change the development method. . Fire flooding has the advantages of wide application range, high oil displacement efficiency and high recovery factor, which can effectively solve the problem of difficult exploitation of heavy oil reservoirs.
In recent years, under the guidance of the Exploration and Production Branch and with the help of experts from the Thermal Recovery Institute of the Exploration and Development Research Institute, Huabei Oilfield has established a technical research team, and decided to carry out a pilot test of fire flooding development in the conglomerate reservoir of the Mongolialin Oilfield. project.
During the construction of the project, the technical personnel of Huabei Oilfield Erlian Branch and related construction units accurately controlled the construction links such as underground, ground, and above-ground, and optimized and improved the construction plan many times. Among them, the microwave cracking technology with advanced technology and low cost was finally selected as the flue gas treatment process through multi-party investigation and comparison and field inspection. This is also the first time that microwave cracking technology has been applied to China's oil fire flooding project. In view of the unfavorable factors such as cold weather in Erlian in winter, the reversed construction plan and the formulation of winter construction technical measures were adopted to ensure the orderly progress of the project.
In the stage of on-site ignition implementation, Erlian Branch innovated its working methods to speed up and improve efficiency. Combined with the relevant experience of other extra-heavy and super-heavy oil reservoirs that have implemented fire flooding in China, and in view of the characteristics of good crude oil properties and large injection-production well spacing in the conglomerate reservoir of Mongolialin Oilfield, the ignition implementation plan was optimized and adjusted, and the ignition temperature was achieved for the first time. In one step, the ignition cycle was shortened from 12 days in the original plan to 7 days. At the same time, in order to ensure the safety of the wellbore, for the first time in the ignition stage, the monitoring pipe was brought to the bottom of the artificial well, which realized the real-time monitoring of the temperature of the whole wellbore, and obtained the first-hand data confirming the formation combustion. Field implementation shows that the ignition adjustment plan was successful.