Abstract

The fierce competition in resource development in the marine field among countries around the world ultimately boils down to the competition in science, technology, and core equipment that support national rights and interests. With the in-depth implementation of China's maritime power strategy and the "the Belt and Road" initiative, offshore oil and gas drilling has made great strides towards the deep sea, and deepwater oil and gas drilling technology and equipment have become an important cornerstone to ensure China's energy security. How to solve the "bottleneck" problem, achieve the localization of key core equipment, and create the source of original drilling technology is a new problem faced by deepwater oil and gas drilling.

In the field of deepwater oil and gas drilling and development, since 2000, new discoveries of global offshore oil and gas have begun to surpass those on land, and reserves and production have continued to grow. Currently, it has become a strategic replacement area for oil and gas resources. In the past 10 years, 70% of major global oil and gas discoveries have come from deep water (deep water generally refers to water depths greater than 500 meters). Among the top 50 super large oil and gas development projects, 3/4 are deep water projects. According to the International Energy Agency, the technically recoverable reserves of global offshore oil and gas in 2017 were 1097 billion barrels and 3.11×10.6 billion m³, accounting for 32.81% and 57.06% of the global total recoverable oil and gas technology, respectively. It is expected that in the next 10-20 years, 50% of global oil and gas production will come from offshore sources, and 35% of global offshore oil and gas production will come from deep water sources.

As the foundation of marine exploration and development, deepwater drilling technology plays a crucial role in the development and utilization of China's marine resources, geological surveys, and environmental evaluation of key coastal zones. It can be foreseen that with the expansion of offshore oil and gas exploration into deep water, deep layer, high-temperature and high-pressure fields, deep water drilling equipment technology has become an important support for ensuring oil and gas exploration and development and subsequent safety supply.

The article provides a brief introduction to deepwater oil and gas drilling technology and equipment, comprehensively analyzes the current situation of deepwater oil and gas drilling technology and equipment at home and abroad, and looks forward to the development trend of key technologies and equipment for future deepwater oil and gas drilling.

1. Characteristics of Deepwater Oil and Gas Drilling Equipment Technology

Drilling is an essential key link in the exploration and development of deepwater oil and gas, which can be vividly likened to "giving the earth a shot". Through drilling, it can directly contact and obtain stratigraphic information such as oil, gas, water, and lithology. Due to the barrier of thousands of meters of seawater, deep water drilling is facing the dual challenges of "going into the sea" and "entering the ground", making it a complex system engineering with high risk, high investment, high-tech, high intensity, and high return.

If a worker wants to do a good job, he must first sharpen his tools. Drilling equipment is the hardware foundation for deep water oil and gas drilling development, and drilling technology is a specific method to solve the practical problems faced in the process of deep water oil and gas resource development. Due to the fact that China started its offshore oil and gas development more than 30 years later than developed countries, coupled with the continuous emergence of various new types of marine equipment, and the limited operating space, concentration of personnel and facilities, high technological difficulty, complex equipment structure, and numerous hazardous and harmful substances of deep and deep sea oil and gas exploration systems, offshore oil and gas drilling operations have extremely high accident risks. Therefore, the development of China's offshore oil and gas resources is facing challenges from shallow to deep water, from conventional drilling to intelligent and environmentally friendly drilling. This poses higher requirements for the equipment and technology of offshore oil and gas development, especially in the fields of deepwater intelligent drilling rigs, Floating Production Storage and Offloading (FPSO) platforms, intelligent platforms, unmanned platforms, and other equipment. There is significant development space in the fields of deepwater oil and gas intelligent drilling, offshore oil and gas big database technology, rotary steering drilling and logging while drilling technology There is still a certain gap between intelligent drilling string technology and European and American countries.

2. Current Status of Deepwater Oil and Gas Drilling Technology and Equipment at Home and Abroad

2.1  Current status of International Deepwater Oil and Gas Drilling Equipment Technology

Currently, the global research and development of offshore oil and gas development technology focuses on offshore ultra-deep water, ultra-high temperature, ultra-high pressure oil and gas drilling technology, integrated deep water drilling development technology, and deep water pressure control drilling technology. In recent years, global offshore oil and gas exploration has shown a continuous trend of expanding towards deep to ultra deep and deep to ultra deep sea areas.

The United States has a complete industrial system and research force in the development of marine oil and gas resources. The United States Department of Energy has 17 national laboratories, including the Lawrence Berkeley National Laboratory and the Los Alamos National Laboratory. Marine oil and gas drilling and development is also one of the key research directions of these laboratories. There are more researchers in the US national laboratory than in universities, and the research field can achieve full coverage from basic science to cutting-edge technology. Meanwhile, due to the strong financial resources of the national laboratory, it can maintain long-term investment in a certain research field, thus achieving breakthroughs in certain strategic directions. In addition, national laboratories usually have special experimental equipment that universities do not have, such as linear accelerators.

There are not many universities in the United States that have the discipline of oil and gas drilling and development, among which comprehensive universities include Stanford University and the University of Texas at Austin; In addition, relevant departments of some oil and gas drilling universities (such as Colorado University of Mining and Tulsa University, etc.) usually adhere to a "small but refined" strategy, mainly focusing on drilling and development technology.

Developed Western countries have always been in a dominant position in the field of deepwater oil and gas drilling equipment, such as drilling platforms (ships). Especially in the more than 10 years from the 1990s to the early 21st century, the number of mobile offshore drilling platforms increased sharply from 56 in 1996 to 670 in 2002, with 111 ultra-deep water drilling platforms (ships) of 1524 meters and above, including 83 ultra-deep semi submersible drilling platforms and 28 ultra-deep water drilling ships (Figure 1). In terms of the adaptability of deepwater oil and gas drilling equipment to drilling depth, Western developed countries have also achieved leapfrog development.In 2002, Chevron drilled a vertical depth of 9210 meters. In 2003, Chevron's drilling work in the Gulf of Mexico in the United States exceeded 3000 meters in depth. These fully demonstrate that Western developed countries have made rapid progress in adapting to deep water and drilling.

Overall, thanks to the advantages of technology, funding, talent, and continuous industrial innovation and upgrading, developed countries led by the United States have formed a complete set of equipment and technology in the field of deepwater drilling, and are in a clear leading position.

2.2  Current Status of Domestic Deepwater Oil and Gas Drilling Equipment Technology

2.2.1  Current Situation of Deepwater Oil and Gas Drilling Technology in China

Starting from the 11th Five Year Plan, projects and topics funded by the state in the field of deepwater oil and gas cover geological exploration, reservoir development, drilling engineering, engineering gathering and transportation, and safety assurance. The research and development content includes basic theoretical research, engineering technology research, equipment development, material research and development, demonstration engineering, etc. (Table 1), achieving deep integration of industry, academia, research and application, and joint research and development, and initially achieving breakthroughs in core technologies The goal is to complete major strategic products, build major oil and gas field projects, and build a joint innovation team. A certain breakthrough has been made in the development of deepwater oil and gas drilling, forming a batch of major technological achievements that strongly support the implementation of the national marine power strategy and oil and gas security strategy.

During the 13th Five Year Plan period, China achieved fruitful results in the field of deepwater drilling. In terms of innovation in deepwater oil and gas drilling technology, China National Offshore Oil Corporation (CNOOC) has basically mastered the design ability of deepwater development drilling, and has the ability to carry out conventional oil and gas field development drilling operations at 1500 meters. It has successfully carried out ultra-deep water high-temperature and high-pressure drilling and testing operations, setting a record for the first deepwater (2619 meters) drilling operation in the Western Pacific, achieving a leap from drilling to development of deepwater oil and gas.

Since 2012, China has independently operated over 100 deep water wells in the South China Sea, supporting the discovery of 5 large and medium-sized deep water oil and gas fields, including China's first independently discovered and explored "Deepsea No.1" ultra deep water atmospheric field (Figure 2), and successfully constructed the world's first 100000 ton deep water semi submersible production, storage, and unloading platform - the "Deepsea No.1" energy station (Figure 3).

As of now, China National Offshore Oil Corporation (CNOOC) has formed four major oil and gas production zones, with a total of 125 producing oil and gas fields, utilizing over 4 billion cubic meters of geological oil reserves and over 700 billion cubic meters of natural gas reserves. It has formed an annual oil and gas equivalent of over 60 million tons and built the "Offshore Daqing", achieving a historic leap in China's offshore oil and gas development from "light blue" to "deep blue". To ensure China's energy security, safeguard China's maritime rights and interests, and build a maritime power, a solid foundation has been laid.