UNCONVETIONAL OIL PRODUCTION. Chemical Stimulation. Patent Bulletin. Aenert. March 2022
Introduction
In the structure of final global primary energy consumption, oil products lead by a significant margin, with the total final consumption of oil exceeding 30%.
The uniqueness of raw materials in the form of fossil fuels, in addition to having the physical and chemical properties optimal for the energy sector, lies in the presence of another tremendous advantage – the possibility of its long-term storage. Located in the bowels of the earth and once extracted from it, oil or gas, can be delivered at the right time to the consumer and used by him for his intended purpose, including the production of electricity. Moreover, despite the multiple cycles of energy conversion from one type to another, such a process is economically profitable and efficient.
Unconventional oil includes high viscosity and high-density oil, kerogen oil or oil shale, oil sands, light tight oil, located in the reservoirs, limestone and sandstone formations with low permeability. Unconventional oil is also often referred to as heavy oil and even extra heavy oil. As light oil is depleted, ordinary light oil is mixed with rock, sand, clay, production-associated materials, etc., which leads to an increase in its viscosity. In addition, residual oil from a depleted field may occur in hard-to-reach areas with low permeability. The production technologies of such oil are similar to those of unconventional oil, which essentially equates them in terms of practical production. On this bulletin and data base, the concept of unconventional oil is used precisely in such a unified interpretation.
In the structure of proven reserves of conventional oil there is an obvious trend – a decrease in light oil and, conversely, an increase in heavy oil and hard-to-recover oil reserves. Progress in the development of technologies for the extraction of hard-to-recover and heavy oil significantly expanded the available reserves of the oil and gas, while increasing the cost of their production and processing. Taking into consideration the increase in the share of hard-to-recover reserves in the global hydrocarbon balance, it becomes clear that the use of these technologies will keep steadily growing. A considerable portion of efficient technical solutions aimed to resolve the aforementioned problems is concentrated in patent documents registered in various patent offices.
Among them, technologies based on the introduction of various activators into hydrocarbon layers, primarily those reducing oil viscosity, are highly popular with oil-producing companies in the field of stimulated recovery of unconventional oil. In particular, the inventors offer multiple variants of activating compositions based on known chemical substances, for instance, polymeric materials, flourinated hydrocarbon, polyvinylalcohol, methyl ether, amines, ammonia, fatty acid, surfactant, reactive particles, etc. The inventions also disclose the options and devices for efficient injection of solvents into oil-bearing strata, optimum well configurations, methods and equipment for forming a suspension, improved modes of oil recovery while injecting hydrocarbon solvents.
From enhanced oil recovery methods, the VAPEX (Vapor-Assisted Petroleum Extraction) method should be mentioned in the first place. This process visually resembles SAGD, however, vapourised solvents are used instead of steam in this case. The process can be characterized by limited greenhouse gas emission, high recovery factor (up to 60%), low energy consumption, and in situ upgrading. Its main shortcomings are: too slow process, not mature technologies, solvent loss in reservoir. Among other methods, it is necessary to mention Microbial Enhanced Oil Recovery where the intensification of production is achieved by introducing a special group of microbes into the reservoir.
A considerable portion of the inventions is dedicated to the aspects of ecological safety when activating chemical compositions are used. Here, improvement of environmental performance is very important at any stage of the technologies, including transportation, storage, preparation or mixing, injection of chemicals, and waste utilization.
Methodology
This patent information bulletin includes a statistical analysis of major attributes of patents and patent applications published in the 20-year period from 2002 to 2021. The bulletin partially reflects the contents of patent database "UNCONVENTIONAL OIL PRODUCTION. Chemical Stimulation" for 1987-2022.
The database was formed in two phases. The first phase included a preliminary collection of patent documents from generally-accessible sources by using conventional methods involving key-words, patent classification indices, applicant and inventor data. During the second phase, to improve the correspondence of inventions to the chosen criteria, the text of all core documents from those, preliminary collected in the first phase were subjected to a thorough subject- and semantic-oriented assessment by experienced engineering personnel. Also, each document in the final version of the database was marked with additional topical indices allowing an in-depth systematization of the inventions.
Opting for such a labour-intensive way to produce a patent database was caused by the fact that subject-oriented search and systematization of inventions are associated with substantial difficulties of technical, linguistic, and methodological nature. Fairly often patent documents have complicated narrative style or imperfect translation, which hampers understanding and unambiguous interpretation. Incompleteness and imperfection of patent classification indices also exist. Moreover, in a number of inventions, main specific keywords are either omitted or used in a completely different semantic meaning. Each patent document in this database contains a list of conventional bibliographical indicators, including original title, English version of the title, family size, application date, publication date, patenting office, names of inventors and applicants, document kind (patent or application), number of claims, number of citing, IPC indices, and core document number.
Also, as it was mentioned above, patent documents were additionally provided with specialized markers – generalized unified indicators that are combined in individual semantic groups: technology categories (indicate the applicability of technical solutions to one of the unconventional oil types); technology elements (indicators showing a level of detailing for the production process); problems (technical, economical, ecological and other problems); type of technical solution (device, method, composition). Besides, the database contains a number of derived indicators, including applicant statuses, the residence of applicants, and Unified Indicator Group. Indicators such as patent pending period, prominent patents, applicant's share in the aggregate intellectual property registry can be calculated based on the available data. For a vast majority of patent documents rating points were also calculated on the basis of bibliographical and unified indicators.
General methodology of patent database compilation and statistical evaluation used in this product can be found at aenert.com. The texts of core patent documents shown in the proposed database can be found in generally-accessible patent search systems, such as Google Patents, Lens, Espacenet.
Key Highlights
Statistical analysis for the 20-year period between 2002-2021 includes:
Inventions: 11724
Offices: 55
Countries: 47
Applicants: 2145
Individual IPC subgroups: 2454
Total IPC subgroups assigned: 38872
In total, 3968 patents and 7756 patent applications were found for the present bulletin. The most active registration of patent applications took place in 2019-2020.
In the 20-year period patents were granted in 34 patent offices around the world. The most popular patent offices with applicants were CNIPA (China), USPTO (US), Rospatent (RU), CIPO (CA), EPO, and IP Australia (AU). In recent years the largest share of registered patent applications was in CNIPA (China), and a considerable increase in patenting activity was seen in INPI (BR). 2145 applicants from 47 countries participated in the preparation of the inventions. About 30% of patents were granted to US applicants and more than 28% to China applicants. The share of Saudi Arabia residents has grown substantially in applicants who registered their applications in the last five years.
IPC indices C09K8/584 (Compositions for enhanced recovery methods for obtaining hydrocarbons, characterised by the use of specific surfactants); E21B43/22 (Obtaining fluids from wells, use of chemicals or bacterial activity); C09K8/588 (characterised by the use of specific polymers) were assigned to patents more than others. Such problems as “High running costs of maintenance” and “Environmental balance and protection” were frequently mentioned in patents and patent applications. Along with “Chemical stimulation”, technology elements “Gas injection or water flooding”, “Reservoir permeability improvement and extraction”, and “Steam injection” were frequently mentioned in patents and patent applications.
A separate portion of the statistical analysis is dedicated to applicants of patent documents. It includes the lists of applicants separately for patents and applications, breakdown of applicants' patent documents by offices, types of technical solution, problems, technology categories, IPC sections. The list of top 10 most productive applicants by the number of patents includes:
Sinopec China Petroleum & Chemical Corporation (CN)
Baker Hughes Incorporated (US)
Sinopec SRIPT Shanghai Research Institute of Petrochemical Technology (CN)
Tatneft (RU)
BASF, SE (DE)
Shell Internationale Research Maatschappij B.V. (NL)
Saudi Arabian Oil Company (SA)
SINOPEC Beijing Research Institute of Chemical Industry (CN)
CNPC China National Petroleum Corporation (CN)
ExxonMobil Upstream Research Company (US)
The concluding part of the analysis includes calculated data that allow the resulting patenting trends to be exposed and main conclusions to be drawn. Such diagrams as the relationship of the number of applications to the number of patents by year, the relationship of the number of single applications to total number by year, and others, are also presented here.
Disclaimer
The present patent bulletin was prepared by EnerTechUp company and its partners. The patent bulletin includes patent documents that were carefully collected from the publicly available sources and, according to the authors, to the greatest degree represent the latest innovations in the particular energy industry as of the date of the patent bulletin preparation. Detailed information on the methodology of search and processing of patent documents is available at Advanced Energy Technologies (www.aenert.com). Considering the difficulties related to the compilation of lists of international patent documents, including those related to time frames, national and terminological barriers, as well as taking into consideration high labour intensity of collecting the required analytical information and performing its qualitative interpretation, the authors of the patent bulletin cannot guarantee absolute completeness and accuracy of the represented materials and disclaim any responsibility for the use thereof. EnerTechUp represents this material “as is” and rejects any claims and liabilities arising from the use of data published therein, including, but not limited to: compensation for any type of financial damage, lost profit or compensation for moral injury. These stipulations also refer to employees, shareholders, agents and data suppliers of EnerTechUp.
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