Original title: Reaping 1 billion tons of new reserves, Daqing Oilfield, looking for the future in shale
Daqing Oilfield has honed its sword for 40 years. With the help of the unconventional oil and gas development of Gulong shale oil, the veteran oilfield will set off again.
The core of oil field development is the issue of resources. Against the background of weak growth and declining development benefits of the main oilfields of Daqing Oilfield, the discovery of Gulong shale oil has helped Daqing Oilfield find new room for growth.
After more than sixty years of development, Daqing, an old oil field, wants to continue to prove itself.
New Daqing found under Daqing
On August 25, Daqing Oilfield held a press conference in Daqing City, announcing the good news of the company’s harvest of a billion-ton shale oil field.
The 21st Century Business Herald reporter learned from the press conference that Daqing Oilfield harvested many high-yield oil wells in the Gulong shale oil area in the northern Songliao Basin. In 2021, the oil-bearing area will be 1,413 square kilometers, and the estimated oil reserves will be 1.268 billion tons. , Has become an important strategic resource for Daqing’s century-old oilfield construction.
Daqing Oilfield is located in the central and western part of Heilongjiang Province, north of the Songnen Plain. It was discovered in 1959, entered the experimental development stage in 1960, and entered the large-scale development stage in 1963.
The Daqing Oilfield is China’s largest oilfield and one of the few super-large continental sandstone oilfields in the world. It was the discovery and development of the Daqing Oilfield in the 1960s that allowed China to remove the “oil-poor country”. hat.
The Songliao Basin, where the Daqing Oilfield is located, is a Mesozoic and Cenozoic inland faulted depression superimposed basin developed on the basis of the Tianshan-Inner Mongolia-Xing’an Paleozoic trough fold system. It is also the continental facies with the most abundant oil and gas resources discovered in the world. One of the sedimentary rock basins.
Over the past sixty years of development and construction, the Daqing Oilfield has produced more than 2 billion tons of crude oil and over 100 billion cubic meters of natural gas, which has made great contributions to maintaining the safety of national oil supply. In 2020, the total oil and gas production equivalent of Daqing Oilfield at home and abroad will still exceed 43 million tons, and it will still be one of the largest oil and gas production bases in China.
In recent years, Daqing Oilfield, like many old oilfields in China, has faced the dilemma of insufficient replacement resources: the grade of new proven oil reserves has been significantly reduced, the difficulty of stabilizing production in major oilfields has become more and more difficult, and the development work has also entered into ultra-high water cut and ultra-high water. At the “double super high” stage of recovery, production and operation costs are increasing year by year, and the overall decline rate is also rising.
In order to solve the problem of insufficient resource reserves in old oil fields, domestic old oil fields have accelerated the development of oil and gas business in overseas markets and domestic transfer of mineral rights blocks. But for oilfields like Daqing Oilfield, it is an inevitable trend to switch from conventional to unconventional oil and gas exploration and development based on the cornucopia of Songliao Basin.
Zhu Guowen, Vice President of China National Petroleum Corporation and Secretary of the Party Committee of Daqing Oilfield, told reporters of 21st Century Business Herald that after 62 years of high-efficiency and high-speed exploration and development, the conventional oil and gas resources of Daqing Oilfield have entered the middle and late stages of discovery, and it is difficult to sustain long-term sustainability. Stable production; and the discovery of Gulong shale oil has realized the dream of generations of Daqing people to “look for Daqing under Daqing”.
Zhu Guowen pointed out that the successful practice of Gulong shale oil indicates that the Songliao Basin has entered the era of unconventional oil and gas development and is an important material basis for the long-term stable production of the Daqing Oilfield.
Forty years to sharpen the sword
The concept of shale oil originally specifically referred to oil extracted from shale containing organic matter by means of man-made oil. It now refers to oil related to shale formations, which is equivalent to or mixed with tight oil in a broad sense.
In recent years, as the growth rate of onshore conventional oil and gas resources has slowed, global oil and gas resource exploration and development have begun to move toward unconventional areas and deep seas. The success of the North American shale oil and gas industry marked the beginning of the shale oil and gas revolution.
Due to the risks and uncertainties in oil and gas exploration, in recent years, the announcement of the results of domestic oil and gas resource exploration is also cautious. The discovery and development of Gulong shale oil has been close to forty years before determining the predicted geological reserves of 1.268 billion tons of newly added oil.
Fractured shale oil reservoirs were discovered in the northern Songliao Basin in the 1980s. In 1981, Daqing Oilfield used conventional crude oil exploration concepts and development techniques to drill the first discovery well in the mudstone fractured reservoir in the Gulong Sag in the Songliao Basin. Since then, many oil wells have been drilled; by 1998, the development of horizontal shale oil wells has begun. Preliminary Study.
In 2011, Daqing Oilfield entered the stage of research and understanding of Gulong shale oil, and 4 development experimental areas realized large-scale development; by 2018, Gulong shale oil entered the test breakthrough stage. At this stage, Daqing Oilfield has significantly increased its shale oil exploration efforts, shale oil exploration concepts, and development technologies.
In 2020, Daqing Oilfield will achieve a major breakthrough in the exploration of continental mud shale oil: Well Ping 1 of the ancient shale located in the Gulong Sag of the Central Depression of the Songliao Basin will obtain high-yield oil and gas flow, demonstrating the vast continental shale oil resources in the area prospect.
On June 20 this year, the forecasted geological reserves of 1.268 billion tons of Gulong shale oil passed the review of China National Petroleum Corporation, realizing the first step in the conversion of resources to reserves.
According to Daqing Oilfield, the main body of Gulong shale oil is pure shale oil, which is different from other types of shale oil at home and abroad. There is no successful case of large-scale commercial development, and its resource endowment conditions and reservoir characteristics They are all unique. They have overturned traditional shale oil exploration and development concepts and cognitions in terms of oil product properties and storage space characteristics.
At the beginning of the discovery, domestic and foreign industries believed that Gulong shale oil could not be used effectively. In recent years, the scientific research team of Daqing Oilfield has successively realized the innovation of oilfield accumulation and development theory, as well as the innovation of characteristic drilling and completion, and fracturing technology. The understanding and development of Gulong shale oil has entered a new stage.
Construction of a net zero emission shale demonstration zone
Compared with the Daqing oil battle sixty years ago, the “new battle” carried out by the Daqing oil field today must reflect the characteristics of technological innovation and green and low-carbon.
At present, Daqing Oilfield is actively promoting the construction of the Daqing Gulong Continental Shale Oil National Demonstration Zone. It is estimated that by the “14th Five-Year Plan” period, 1 billion tons of proven oil reserves will be added, and the annual output of shale oil will reach more than 1 million tons. .
According to the current plan, Daqing Oilfield will implement drilling of 100 wells in Gulong shale oil in 2021. At present, 58 wells have been drilled, 27 wells have been tested, 25 wells have seen oil, and 17 wells will be harvested for industrial oil and gas flow.
Daqing Oilfield will promote the construction of a national demonstration zone for shale oil, while adhering to net zero emissions first.
He Wenyuan, deputy general manager and chief geologist of Daqing Oilfield, pointed out that in the construction of the Gulong shale oil national-level demonstration zone, the company will build a net zero emission pilot demonstration zone, through the injection of carbon dioxide into the formation, and carry out the reuse and harmlessness of fracturing flowback fluid. Chemical treatment, the promotion of electric drive replacement of drilling rig construction equipment, and the integrated utilization of new energy wind and photoelectricity have achieved the goal of net zero emissions from shale oil production.
The team of academicians and experts related to Gulong shale oil believes that the exploration and development of Gulong shale oil has many demonstration and leading significance.
In science, Gulong shale oil has achieved a theoretical breakthrough from continental shale oil generation to continental shale oil production; in an economic sense, Gulong shale oil will help Daqing Oilfield get rid of the imbalance of storage and production in old oilfields. , To achieve an increase in the total scale of oil and gas; in terms of industry, it will drive the leap-forward development of Daqing’s upstream and downstream integrated ethylene industry chain and value chain.
In terms of social significance, Daqing will also use the discovery of Gulong shale oil to become a pioneer in the transformation and development of resource-based cities in the country; and in terms of demonstration and leading significance, the discovery of Gulong shale oil will promote China’s continental shale oil and gas revolution The progress of the global shale oil and gas development.
According to the 21st Century Business Herald reporter, the Daqing Oilfield’s Ping An 1 well in the Sichuan-Chongqing exploration area was tested in the Jurassic Lianggaoshan Formation shale to produce a high-yield oil flow of over 100 cubic meters of oil and 100,000 cubic meters of gas, which is Gulong shale oil. The viewpoints and methods are practiced and replicated in the Sichuan Basin continental shale oil.
Although the prospects are promising, to realize the large-scale development of shale oil and gas, we still need to face the problems of cost and technological innovation.
The research team of Gulong shale oil in Daqing Oilfield pointed out that compared with shale dominated by marine or salt lake basin sedimentation, Gulong shale is very different in rock fabric, physical properties, oiliness and fluidity of shale oil. , North America’s mature geological theories and engineering technologies are difficult to directly apply, and are faced with challenges such as high investment costs for single wells, low initial production, final recoverable reserves of a single well below the economic production threshold, and the lack of the main technology for scale-benefit development.
Therefore, the realization of Gulong shale oil development theory and technological innovation has become the most urgent and urgent task at present.
(Author: Peng Qiang, Editor: Zhang Weixian)