,,

Oil and gas exploration goes deep

Release time: 2020/8/26

The National Energy Administration recently issued the guidelines for Energy Work in 2020 (hereinafter referred to as the Guidelines).The Opinions emphasized that multiple measures should be taken simultaneously to enhance the capacity of oil and gas security.Among them, "increase oil and gas exploration and development efforts" is listed as the first task."Why the emphasis on oil and gas exploration when oil prices are so low and you can buy oil abroad?"In the face of public doubts, Jin Zhijun, director of the State Key Laboratory of Shale Oil and Gas Enrichment and Effective Exploitation and an academician of the Chinese Academy of Sciences, told China Science Daily that oil and gas, like food and water, have become human necessities and strategic materials related to national security.It will be an important task of national strategy to ensure the safety of national oil and gas instead of relying solely on imports and to intensify exploration and development based on domestic development.
The consensus of many oil and gas exploration experts is that deep, deep and shale oil and gas exploration will be the main direction in the future, and adhering to efficient exploration and benefit development is also the inevitable choice for the sustainable development of the oil and gas industry.
?

Oil and gas Exploration "from shallow to deep"

Increasing domestic oil and gas exploration and development efforts continue to be highly concerned by the industry inside and outside.In recent years, the continuous increase of policy and the progress in the exploration field have injected a shot in the arm into China's oil and gas industry.The steady increase in the output of many old oilfields, such as Shengli Oilfield, has also played an active role as "ballast".

"The world's oil and gas growth is still at its peak, and China's oil and gas storage production growth is also at its peak, which is expected to continue until 2050."Kang Yuzhu, a petroleum geologist and academician of the Chinese Academy of Engineering, estimated that China's crude oil output is expected to reach 230 million to 250 million tons and natural gas output to reach 350 billion to 400 billion cubic meters by 2050.

In the future, China's oil and gas exploration will shift from the east to the west, from the land to the sea, and from the middle and shallow layers to the middle and ultra-deep layers, according to the global oil and gas development trend, Kang told China Science Daily.In addition, with the development of exploration and development theories and technological progress, it has become an important goal for oil and gas companies to search for oil and gas resources in deeper and older strata.

According to our correspondent, deep-seated oil and gas resources have been the main source of growth in the world's proven reserves in the past decade, and the limit of effective resources' depth has been continuously exceeded.From 2008 to 2018, the world's proven reserves of oil and gas increased by 23.4 billion tons of oil equivalent at a depth of 4,000 meters, accounting for more than 60% of the world's new oil and gas reserves during the same period. The maximum depth of oil and gas drilling reached 12,869 meters.

Deep water has also become the focus of recent oil and gas accumulation, with major discoveries mainly concentrated in passive marginal basins such as the Atlantic, East Africa and the Mediterranean.From 2008 to 2018, the world's proven oil and gas reserves in offshore waters reached 21.7 billion tons of oil equivalent, accounting for 68% of the world's new proved oil and gas reserves, of which deepwater -- ultra-deep water accounted for more than 40% of the world's new recoverable reserves.

Jin zhijun said China's deep oil and gas exploration has expanded from 4,000 to 5,000 meters in the past to 6,000 to 8,000 meters.In addition, Marine shale gas and terrestrial shale oil at a depth of 3,500 meters will be key breakthrough areas for oil and gas exploration in China.

However, venturing into the restricted zone of deep exploration is also an "extreme challenge" for the entire oil and gas industry.?

Conquer "jam neck" technology

The whole process of oil and gas exploration is like a concerted operation of thousands of troops and horses, which is a very large systematic project.To go deep into the earth, we must first face a variety of engineering problems.

"The distribution of oil and gas in deep layers is different from that in shallow layers. As the depth of burial increases, so does the density of the rock."To achieve high yields requires a full suite of drilling and fracturing technologies suitable for deep oil and gas exploration, which poses challenges for both equipment and technology in China."Jin Zhijun said frankly that the core of oil and gas exploration of the rotary steering drilling system is China's urgent need to overcome the "neck" technology.

Rotary-guided drilling, a cutting-edge automated drilling technology that allows drill bits to travel like "snakes" through thousands of meters of hard rock to hit their targets, is even more demanding than missile guidance.

"The missile's medium is air, and once all the parameters have been calculated, effective control can be achieved.And the underground medium is changing all the time, which is extremely demanding."Jin zhijun said that most of the equipment in China is rented from abroad, which increases the cost for oil and gas exploration and development. Therefore, the next step of the rotary steering drilling system will be one of the key core technologies that China must conquer.

In addition, for shale gas exploration and development, member of Chinese Academy of Sciences, China university of petroleum (Beijing) professor mark godley tell proceedings in China, based on cluster horizontal Wells at home and abroad "well factory" is the basic features of shale gas efficient development mode, the mainstream of the engineering work and to create a large factories "" well, you must challenge the limit of large displacement horizontal well engineering work.

"Under certain subjective and objective constraints, there is an allowable limit for the hole length of any actual horizontal well that can be built, which is called the extension limit of the horizontal well."Mark godley, points out that at present our country has built many small factories "well" (mostly well type 4 or 6 well type), the total built hundreds of shale gas horizontal well, but I haven't a well is the definition of large displacement horizontal well, which seriously restricts the large factory "well" the creation of a reviewable by strengthen the interdisciplinary research for technological breakthrough by leaps and bounds.

Godley pointed out that due to the complexity of technology and equipment, enterprise operation economy and many other constraints, China's engineering operation capacity and technology and equipment level compared with the international leading level is still a large gap.?

Low-cost technology is key

"Without technological progress, cost-effective development is impossible."Jin stressed that low-cost technology will be the next important direction of technological progress for the entire oil industry.

For shale oil with medium and low maturity, high viscosity and low fluidity, it is necessary to study its enrichment and flow mechanism in the future and establish a set of low-cost underground in situ modification technologies, including underground fracturing technology, in situ heating technology and anti-corrosion technology, he said.

Jin zhijun also pointed out that the low volatility of oil prices is bound to push the industry from the past "resource-expanding" technology progress to "cost-reducing and efficiency-enhancing" technology progress.In the process, information technology and artificial intelligence are reshaping the oil and gas industry.

"I predict that the application of a new generation of information technology, with artificial intelligence, big data and block chain technology as the main body, can reduce the cost of the oil industry by 20 to 30 percent."Jin zhijun said.

Kang also said that future oil and gas exploration will require cross-border integration of new technologies, new materials and intelligent informatization, as well as increased research and development of offshore and deepwater oil and gas exploration and development technologies and equipment.China should focus on strategic objectives, highlight key issues, break through "jam neck" technology, and form disruptive technologies through cross-border integration based on national oil and gas exploration needs from 2020 to 2035, so as to master core technologies in strategic fields.

Mark godley is recommended, and the state should be established as soon as possible, an advanced natural gas development and utilization of security monitoring and security system (including technical standards, operation mechanism and regulatory system and target responsibility, etc.), ensure that the gas drilling, mining, long distance pipeline transportation, storage, distribution network and the terminal reserve use and so on each link of the safety and reliability, as far as possible to reduce or avoid the happening of gas major workplace accidents.

And starting from the domestic and international market demand, mark godley advice, to move, through policy guidance and administration to the existing national oil and gas group company of the relevant technology and human resources as the foundation, through the joint-stock restructuring mode, and refer to the international famous oil and gas engineering and technical services company in the business management and the successful experience of the respect such as organization management, to establish and nurture internationally competitive oil and gas engineering technical services company, and allow more than two independent legal enterprise exist at the same time, to keep the oil and gas engineering market competition vitality.

"The professional technology services company, should have technology research and development and the basic characteristics of the service integration and the internationalization of market management, should be similar with the international first-class technical service company for the pursuit of goals, both for China's oil and gas companies (or investment subject) in oil and gas exploration and development investment projects at home and abroad to provide strong technical support, and can obtain the huge technical service revenue, strive to gradually form a virtuous cycle.""Said Godley.?

Next：Chemical valve selection

Previous：How to identify valve identification paint?