On December 27, 2020, the annual oil and gas equivalent of Changqing Oilfield of CNPC exceeded the high point of 60million tons, which set a new record of annual oil field production in China. As the old "three low" oil fields with low pressure, low permeability and low abundance in the past, Changqing Oilfield has solved the problems through technological innovation, constantly broke through the theory and technology of geological exploration, and realized scientific management, which has brought new features in recent years.
At 10:00 on December 27, the large screen of Changqing oilfield production command center of CNPC showed that since this year, the production of crude oil has reached 24518 million tons, and the production of natural gas is 44.531 billion cubic meters, with an annual oil and gas equivalent of more than 60million tons, reaching 608000 tons, which has set a new record of annual oil field production in China.
Changqing Oilfield, which has been exploited for 50 years, can be called "late completion of great instruments". From the establishment of the oil field in 1970 to the end of last century, Changqing oilfield production has been hovering in the past 10 million tons for a long time. However, the old oil field has a new look after entering the new century. In 2012, it became the first oil and gas field in China, and has contributed more than 760 million tons of oil and gas equivalent; As the largest natural gas production base in China, Changqing Oilfield has undertaken more than 50 large and medium-sized cities' gas supply task. Since the official gas supply to the outside in 1997, it has produced 466.6 billion cubic meters of natural gas, equivalent to replacing 562 million tons of standard coal and reducing carbon emissions by 1.529 billion tons.
Technical innovation shows its skill: solving the problems of low pressure, low permeability and low abundance
In 2000, the oil and gas production of Changqing Oilfield exceeded 5million tons for the first time. Since then, the output of Changqing Oilfield has been rising for 20 years in a row - in 2003, it exceeded 10million tons, in 2007, in 2009, 30million tons, in 2011, and in 2013, 50million tons. This year, it has exceeded the high point of 60million tons, and has jumped to a new historical height of single oil field production in China.
Why can such an old oil field create a miracle of 60million tons of oil and gas equivalent per year?
"In the past, Changqing Oilfield has been unable to develop, mainly because of its poor geological resources endowment, and the oil and gas resources are mainly low-pressure, low permeability and low abundance" three low "resources." Gaochunning, President of Changqing Oilfield Exploration and Development Research Institute, explained one by one:
"Low pressure" - if the pressure coefficient of the reservoir is greater than 1, the oil well will have natural production capacity. The pressure coefficient of Changqing Oilfield is only 0.6-0.9, which is 1 / 3-1 / 2 of the conventional oil field. Even if the artificial pressure is adopted, the net production will decrease rapidly;
"Low permeability" - in the world, the oil fields with permeability less than 50 millidarcy are called low permeability oilfields, while 70% of the reservoir permeability in Changqing Oilfield is less than 1 millidarcy, "the domestic grindstone can be infiltrated in 5 seconds, and water can be penetrated on the reservoir core of Changqing Oilfield, and the oil can be penetrated in 1 minute and 20 seconds, and the oil can be squeezed out from the rocks which are denser than the grindstones, The difficulty can be imagined;
"Low abundance" - the conventional oil field reservoir is usually tens of meters or even hundreds of meters, while the reservoir thickness of Changqing Oilfield is generally less than 10 meters, which leads to the very low production of single well. If we want to produce, only more wells should be drilled.
There is no precedent at home and abroad, and there is no ready-made experience to follow. For Changqing Oilfield, whether it is survival or development, we should first solve the problem of "three low", and the most powerful method is innovation.
Optimize perforation process, oil reservoir fracturing transformation, oilfield water injection development, oilfield dynamic monitoring, water injection reservoir research, oil production technology, oil and gas gathering and transportation technology, cluster drilling... Through the development of 8 supporting technologies, three series of technologies are developed to promote the improvement of single well productivity, stable production and recovery rate, and improvement of overall development efficiency. Ansai Oilfield has comprehensively solved the three major technologies, namely, surface to underground The problems of benefit development from drilling to oil production, from input to output not only formed an annual output of 3million tons, but also created the first officially named development mode in the history of Chinese petroleum Ansai.
There are many innovations like this: to constantly innovate fracturing technology and solve the low permeability problems. Nowadays, the volume fracturing engineering technical indexes of Changqing oilfield can be compared with the international advanced level. The maximum liquid volume of single well is 70000 cubic meters, the amount of sand entering the ground is 12000 tons, and 48 sections of single well reconstruction section are 248 clusters, all of which have set the highest record in China; The limit of low permeability development also decreased from 10 to 1 and 0.5; DMS soluble ball socket fracturing tool and EM30 slip hydraulic fracturing fluid, which have been independently developed, fill in the technical gap in China, which is 50% - 60% lower than the cost of similar products abroad, and become the technical tool of CNPC.
With the "holding" of high-precision technology, Changqing oil fields have been revived one by one. Sulige gas field, which has been under trial production for 5 years and with a daily average output of only 587000 cubic meters per day, was generally not optimistic at first. Now, it has not only survived but also lived brilliantly. In 2012, Sulige gas field surpassed Tarim Kela 2 gas field and became the largest gas field in China.
Theoretical innovation and base gas: geological exploration theory and technology breakthrough help steady production and high yield
There is a saying in the oil field that "reserves are king". Changqing oilfield can achieve production increase for many years and finally stand at a new height of 60million tons. The continuous breakthrough of geological exploration theory and technology is an important foundation.
"In the end, reserves are the foundation of survival and development," said Fu suotang, Secretary of the Party committee and executive director of Changqing Oilfield Company. Through the continuous breakthrough of exploration theory and technology, Ordos basin can become a real "treasure basin", which is also the base gas for our development
"The higher a tree grows, the deeper the root is." Yaojingli, deputy manager of exploration and development division of Changqing Oilfield, told reporters that in the past 50 years, Changqing Oilfield has innovated and formed six geological theories from the most original and basic research, and promoted the sustainable development of oil and gas exploration in Ordos Basin.
For example, Changqing Oilfield developed the reservoir forming theory of paleogeomorphic reservoir, formed a new understanding of "far source hydrocarbon supply, multi-stage transmission, stratigraphic structural trap and three-dimensional distribution of reservoir", broke through the restricted area of exploration of highland and ancient river. By adhering to the exploration thinking of "up and down the mountain and downstream river and extending vertically", many Jurassic reservoir groups were found, Among them, Maling oilfield, which opened the curtain of large-scale oil exploration and development in Ordos Basin, is included. In recent years, relying on this theoretical innovation, the annual increase of efficient reserves has exceeded 50million tons.
"With the continuous breakthrough of geological theory, the key geophysical technologies integrated and innovated by us also strongly support the exploration and development of oil and gas fields." Gao said. In recent years, the wide-directional 3D seismic exploration technology in Loess Plateau, which was jointly excited by borehole gun and vibrator and received by wireless node instrument, has solved the world-wide problems of severe seismic wave absorption and attenuation and poor imaging in the Loess Plateau. The oil and gas enrichment area has been accurately predicted, which effectively supports the implementation of scale reserves and efficient exploration and development.
The innovation of geological exploration theory and technology makes Changqing Oilfield expect to continue to produce and produce stably after 60million tons of high yield. Up to now, Changqing Oilfield has accumulated proved oil reserves of 5.9 billion tons and proved natural gas reserves of 4trillion cubic meters, accounting for 20% of the total amount of domestic proven oil and gas resources. The newly proved reserves of petroleum exploration exceed 300 million tons for 10 years, and the newly discovered reserves of natural gas exploration for 14 years exceed 200billion cubic meters, and the newly discovered oil and gas reserves account for more than 50% of the newly added oil and gas reserves in China.
Management innovation can achieve the great improvement of production efficiency through actual effect.
The trouble with Changqing Oilfield is that the overall reserves are large but the output of single well is small. If you want to go to scale, you can only drill more wells. In this way, the cost will be higher and the product competitiveness will be discounted“ To solve this problem, only by scientific management and the application of advanced scientific and technological achievements, can we achieve the "five provinces" that are time-saving, time-saving, labor-saving, human and money saving. " Said the fulock hall.
"In accordance with the modern international" oil company "model, Changqing Oilfield has constantly emancipated its mind, continuously deepened reform, and implemented a management mechanism of" fully authorized, graded responsibility and process control ", which has greatly improved the production efficiency, said Wang Chen, Minister of the Organization Department of the Party committee of Changqing Oilfield
Robot on the ground, UAV in the sky. The wide application of new technology is also a powerful helper for Changqing Oilfield to realize "five provinces".
As early as 2014, Changqing Oilfield launched UAV well inspection project in the national oil system. As the test field of UAV patrol wells, oil areas such as Eastern Gansu and Northern Shaanxi have completed the workload that can only be completed in one day by manual inspection. Now it can be completed in an hour. At present, Changqing Oilfield has applied UAV inspection technology to ecological environment, public security inspection, well station and oil pipeline safety and leakage monitoring.
The wide application of information technology makes many stations in Changqing Oilfield have been unattended. According to Xia Zheng, general manager of Xi'an Changqing science and Technology Engineering Co., Ltd., there are 1019 unattended reconstruction of medium and small stations in Changqing Oilfield from 2017 to 2019 alone.
Through the integration of industrialization and information technology, Changqing Oilfield has managed the exploration, development, production, gathering and transportation, production assistance and other links of oil and gas fields "into computer", which greatly improves the production and working efficiency. At present, the digitization rate of Changqing Oilfield has reached 96.7% and the digital rate of gas field reaches 100%.
"The annual oil and gas equivalent increased from 20million tons to more than 60 million tons, and the management of oil and gas wells increased from 23600 to 89000, while the employment of Changqing Oilfield has been kept at 70000 people." With the help of the reform of the system and the integration of the two, the labor productivity and competitiveness of Changqing Oilfield have been greatly improved.