Aenert news. Invention analysis
In one of our recent articles (18.06.2023) we have revised patenting trends in the field concerning hydraulic fracturing proppants, their production, structure and composition. We also addressed related subjects in our articles concerning Shale oil and gas production (Energy, Gas & Water consumption on 29.11.2021 and Ecology & Environment on 04.02.2022), and unconventional gas production (10.03.2021 and 17.03.2021).
Now we will take a look at new advancements in the field of hydraulic fracturing fluids used to fracture hydrocarbon formations and deliver proppants for fracture reinforcement. For this purpose we have collected more than 13000 inventions published over the past 20 years and analyzed them using the Advanced Energy Technologies methodology. The patents and patent applications under revision were published in 49 patent offices around the world by 1758 applicants from 40 countries.

Hydraulic fracturing fluids. Cumulative number of patents and applications*, relationship of number of applications to total number of documents by year


*Areas representing patents and applications are overlapping

The peak values in the number of patent applications were achieved in 2014-2019. The largest numbers of published patents were registered in 2016-2020. In the most recent years, the number of collected patent applications and patents has declined. The share of start documents that didn’t belong to any previously formed patent family in recent years was varying greatly in the range of 14-60%.

The number of newly appearing applicants in the collection of documents related to hydraulic fracturing fluids was on the rise in 2011-2013 and in 2017-2019. In the case of new IPC subgroups appearing in the selection, the number was growing until 2017, with moderate values in the recent years. The appearance of new patent offices was varying throughout the 20-year period without noticeable peaks or declines, except for the last two years, when no new offices appeared in the collection. This shows that this field of technology continues to attract new companies and organizations, and it is expanding to new geographical and technological areas, although the rates are seemingly declined in the most recent years.

In the collection of documents under revision, the largest number of patents were granted during 20 years in the USPTO (US) patent office – more than 33% of all patents. CNIPA (CN) and CIPO (CA) were following the leader with almost 20% and 14%, respectively. IP Australia (AU), EPO, and Rospatent (RU) should also be mentioned as the offices each having a considerable number of patents. In the pool of recent patent applications, CNIPA (CN) was in the lead with about 28%. It was followed by USPTO (US) with almost 22% and WIPO with almost 10%.

Hydraulic fracturing fluids. Breakdown of inventions by patent offices. Patents, 20 years (left); Applications, 5 years (right)



The residents of the United States are leading in terms of the number of patents granted during the 20-year period with a share exceeding 60% of all cases, and recent patent applications – with a share of almost 46%. In the former case they are followed by the residents of China (around 16%) and the Netherlands (around 5%), while in the latter case – by China (around 24%), and Saudi Arabia (more than 8%).

Below we provide a list of top 10 applicants with the highest Market involvement ratio for patents published in the 20-year period (Market involvement ratio = volume ratio multiplied by ownership ratio, where Volume ratio - share of applicant documents in total number of documents, Ownership ratio - applicant's participation share in total number of documents):

Hydraulic fracturing fluids. Top applicants by Market involvement ratio. Patents

In the pool of patents describing the composition or production of hydraulic fracturing fluids, Halliburton Energy Services, Inc. (US) has a strong lead by the number of documents among all applicants – 1158 patents. It is followed by Baker Hughes Incorporated (US) - 240, Schlumberger Technology Corporation (US) - 208, Schlumberger Technology B.V. (NL) - 161, and PetroChina Company Limited (CN) - 105 documents. In terms of recently published patent applications, the leaders were Halliburton Energy Services, Inc. (US) - 959, Saudi Arabian Oil Company (SA) - 241, and Baker Hughes Incorporated (US) - 141.

Hydraulic fracturing fluids. Top applicants by Market involvement ratio. Applications

When considering problems, the inventions related to hydraulic fracturing fluids aim to solve, Low efficiency / Main processes comes first in the pool of patents and recent patent applications collected for this analysis. It is followed by High OPEX / Operation and consumables and Ecological balance in terms of popularity. In the vast majority of cases, technical solutions disclosed in the patent documents under revision were represented in the form of compositions. Methods were encountered less often, while the number of devices was even smaller. The most popular IPC subgroups assigned to the patent documents were: C09K8/68 (containing organic compounds), E21B43/26 (by forming crevices or fractures), E21B43/267 (reinforcing fractures by propping), C09K8/60 (Compositions for stimulating production by acting on the underground formation), and C09K8/80 (Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open).

The largest patent family in the pool of documents collected for the present analysis includes 47 patent documents and is represented by core document EA6867B1 (Core document is a base document for which a complete description of the invention is available in generally-accessible patent databases). It is followed by patent families with core documents WO2016160927A1 (46 patent documents) and WO2018172684A1 (42 documents):

ВОДНАЯ ВЯЗКОУПРУГАЯ ЖИДКОСТЬ (en: AQUEOUS VISCOELASTIC FLUID) / P: EA6867B1 / IPC: E21B43/26, B01F17/00 / HUGHS TREVOR, JONES TIMOTHY GARETH JOHN, TUSTIN GARY JOHN, ZHOU JIAN / SCHLUMBERGER TECHNOLOGY B.V / Appl. date: 13/02/2002; Publ. date: 28/04/2006 / Eurasian Patent Organization / Core document: EA6867B1 / Technology categories: HF / Technology elements: FWF / Problems: LEMP / Technical solution types: C / Claims: 17 / Rating: 14

FRACTURING FLUIDS AND METHODS OF TREATING HYDROCARBON FORMATIONS / A: WO2016160927A1 / IPC: C09K8/80, C09K8/035, E21B43/267 / NELSON Scott Gregory, ZHOU Jia, LI Leiming / BAKER HUGHES, A GE COMPANY, LLC / Appl. date: 30/03/2016; Publ. date: 06/10/2016 / World Intellectual Property Organization / Core document: WO2016160927A1 / Technology categories: HF / Technology elements: FWF / Problems: LEMP / Technical solution types: C / Claims: 15 / Rating: 10

FLUIDE DE FRACTURATION COMPRENANT UN (CO)POLYMERE D'UNE FORME CRISTALLINE HYDRATEE DE L'ACIDE 2-ACRYLAMIDO-2-METHYLPROPANE SULFONIQUE ET PROCEDE DE FRACTURATION HYDRAULIQUE (en: FRACTURING FLUID COMPRISING A (CO)POLYMER OF A HYDRATED CRYSTALLINE FORM OF 2-ACRYLAMIDO-2-METHYLPROPANE SULPHONIC ACID AND HYDRAULIC FRACTURING METHOD) / A: WO2018172684A1 / IPC: C07C309/15 / FAVERO Cédrick, KIEFFER Johann / S.P.C.M. SA / Appl. date: 19/03/2018; Publ. date: 27/09/2018 / World Intellectual Property Organization / Core document: WO2018172684A1 / Technology categories: HF, TG, TO / Technology elements: FWF / Problems: LEMP / Technical solution types: C / Claims: 16 / Rating: 7

The following abbreviations are used in the documents hereinbefore and hereinafter: C - Composition; D - Device; M - Method; DD - Directional drilling; HF - Hydraulic fracturing; TG - Tight gas / Shale gas; TO - Tight oil; DR - Drilling and well elements; FEM - Hydraulic fracturing equipment and methods; FO - Other equipment, methods and materials for fracking; FPA - Hydraulic fracturing materials / Propping agents; FWF - Hydraulic fracturing materials / Working fluids; EB - Ecological balance; HCEI - High CAPEX / Exploration and Infrastructure; HCEP - High CAPEX / Equipment production; HOOC - High OPEX / Operation and consumables; HORR - High OPEX / Repair and replacement; LEMP - Low efficiency / Main processes; UP - Unclear problem.

Hydraulic fracturing fluids. Breakdown of documents by family size. Patents and applications



The following are several examples of patents with the highest rating calculated in accordance with the Advanced Energy Technologies methodology in the collection of documents in the field of hydraulic fracturing fluids:

Hydraulic fracturing fluids. Prominent patent documents by rating:

Compositions and methods for treating a subterranean formation / P: US7028775B2 / IPC: E21B43/27 / Fu Diankui, Chang Frank / Schlumberger Technology Corporation / Appl. date: 27/04/2005; Publ. date: 18/04/2006 / United States Patent and Trademark Office / Core document: EA6813B1 / Technology categories: HF / Technology elements: FEM, FWF / Problems: EB, HOOC / Technical solution types: C, M / Claims: 8 / Rating: 22

Internal breaker for oilfield treatments / P: US7857051B2 / IPC: E21B43/267, E21B43/27, C09K8/68, C09K8/76 / Abad Carlos, Lee Jesse C, et al. / Schlumberger Technology Corporation / Appl. date: 15/03/2010; Publ. date: 28/12/2010 / United States Patent and Trademark Office / Core document: EA14811B1 / Technology categories: DD, HF / Technology elements: FEM, FWF / Problems: HOOC, LEMP / Technical solution types: C, M / Claims: 26 / Rating: 22

METHODS OF STIMULATING A SUBTERRANEAN FORMATION COMPRISING MULTIPLE PRODUCTION INTERVALS / P: CA2589798C / IPC: E21B43/25 / EAST LOYD E JR, CAVENDER TRAVIS W, ATTAWAY DAVID J / HALLIBURTON ENERGY SERVICES, INC. / Appl. date: 18/10/2005; Publ. date: 08/06/2006 / Canadian Intellectual Property Office / Core document: RU2398959C2 / Technology categories: DD, HF / Technology elements: DR, FEM, FPA, FWF / Problems: HOOC, LEMP / Technical solution types: M / Claims: 59 / Rating: 22

Stimulating fluid production from unconsolidated formations / P: AU2001023151B2 / IPC: E21B43/26, C09K8/68, C09K8/80 / Nguyen Philip D, Brumley John L, Weaver Jimmie D / Halliburton Energy Services, Inc. / Appl. date: 21/02/2001; Publ. date: 15/01/2004 / IP Australia / Core document: US6257335B1 / Technology categories: HF / Technology elements: FEM, FWF / Problems: HORR, LEMP / Technical solution types: C, M / Claims: 31 / Rating: 22

用于传输处理流体的系统和方法 (en: System and method for delivering treatment fluid) / P: CN104271877B / IPC: E21B43/26 / SHAMPINE ROD, LEUGEMORS EDWARD, LESKO TIMOTHY M / PRAD RES & DEV LTD / Appl. date: 08/03/2013; Publ. date: 07/01/2015 / National Intellectual Property Administration / Core document: US20130233542A1 / Technology categories: DD, HF, TG / Technology elements: FEM, FWF / Problems: EB, HCEI, HCEP, HOOC, LEMP / Technical solution types: C, D, M / Claims: 40 / Rating: 22

Aqueous-based tackifier fluids and methods of use / P: US7131491B2 / IPC: E21B33/138, E21B43/04, E21B43/267 / Blauch Matthew E, Welton Thomas D, Nguyen Philip D / Halliburton Energy Services, Inc. / Appl. date: 09/06/2004; Publ. date: 07/11/2006 / United States Patent and Trademark Office / Core document: RU2382066C2 / Technology categories: HF / Technology elements: FEM, FO, FWF / Problems: LEMP / Technical solution types: C, M / Claims: 65 / Rating: 21

BORON CROSSLINKERS FOR FRACTURING FLUIDS WITH APPRECIABLY LOWER POLYMER LOADING AND RELATED METHODS AND COMPOSITIONS / P: CA2741273C / IPC: C07F5/02, C07F5/04, C09K8/68 / SUN HONG, DE BENEDICTIS FRANCES, QU QI, PARDUE JERRY EDWIN / BAKER HUGHES INCORPORATED / Appl. date: 19/10/2009; Publ. date: 14/03/2017 / Canadian Intellectual Property Office / Core document: CA2741273A1 / Technology categories: HF / Technology elements: FEM, FWF / Problems: HOOC, UP / Technical solution types: C, M / Claims: 34 / Rating: 21

In the pool of patent documents collected for the present analysis, we have outlined three large groups representing some of the trends in the technical solutions related to solar tracking sensors. The groups include patent documents solving the problems of Low efficiency of main processes (improving hydraulic fracturing effect and proppant delivery rate, and increased hydrocarbon yield), High operational costs related to operation and material consumption, and ecology-related problems. Below are several examples of documents from these groups:

- US10494565B2 - enhanced production of hydrocarbon fluids achieved using a Winsor type IV microemulsion that consists of water, organic solvent (naphthalene depleted alkyl arenes, terpenes, etc.), co-solvent including alcohol, and N-Alkyl-N-acylglucamine surfactant comprising C5-C21 hydrocarbon residue and C1-C4 alkyl group;

- US20200325387A1 - a fracturing fluid comprising a base polymer such as an acrylamide-based or polyacrylamide-based polymer, and a nano-crosslinker comprising a base fluid, a nanomaterial (silica, cellulose, carbon-based materials, or their combinations) and a crosslinker (carbonyl, sulfhydryl, amine, or imine), aimed at avoiding formation damage and gas flow conductivity reduction caused by incomplete degradation of polymers;

- US10829683B2 - a method of producing a fracturing fluid with a high concentration of proppant involves supplying liquid CO2, adding proppant to the CO2 stream at a concentration of up to 20 lbs/gal, and routing the combined stream to a well head. A second stream containing water is supplied to the well head, where the streams are mixed to form a fracturing fluid with a Mitchell quality of at least 50%. The method is aimed at reducing the amount of fluid used to place the required amount of proppant;

- US20190055463A1 - fracturing fluid composition comprising an aqueous base fluid, a chelating agent, and a polymeric additive comprising a copolymer of acrylamido-tert-butyl sulfonate and partially hydrolyzed polyacrylamide. Inter alia, the invention is aimed to minimize loss of fracturing fluid;

- US11319482B2 - a fracturing fluid comprising mineral oil, dry powder polyacrylamide with a particle size below 500 μm, guar with a particle size below 500 μm and a minimum solution viscosity of around 3,500 cP at 1%, and other components. The authors point out the need to create a safe and environmentally friendly fluid with more effective friction reduction.

Low efficiency / Main processes

Patent US10494565B2 by Clariant International AG (CH) describes a microemulsion that is used to recover fluids during fracturing operations and stimulate oil or gas wells. The microemulsion is a Winsor type IV microemulsion that consists of water, at least one organic solvent with a flash point above 37.8°C and a pour point of 10°C or lower (2-15 wt.%), co-solvent (1-6 wt.%) that includes alcohol, and N-Alkyl-N-acylglucamine surfactant (12-30 wt.%). The glucamide surfactant in the microemulsion is represented by a compound of formula represented on image below, where Ra is a C5-C21 hydrocarbon residue and Rb is a C1-C4 alkyl group. Further, Ra can be a C7 to C15 hydrocarbon, an aliphatic group, or alkyl or alkenyl, while Rb can be methyl. The organic solvent of the invention is selected from "…naphthalene depleted alkyl arenes, terpenes, paraffinic solvents, fatty acid alkyl esters and butyl glycol ethers". The microemulsion may also include mutual solvents (up to 10 wt.%, 2-ethylhexanol, ethers of 2-ethylhexanol with ethylene glycol, polyethylene glycols, propylene glycol, or their mixtures).

The authors claim that the invention allows "…for faster return of well service fluid and enhanced production of hydrocarbon-containing fluids".

The patent is a part of a family comprising 12 patent documents published in 2016-2022 in the CA, WO, EP, CO, US, CN, and BR patent offices.



Image from: US10494565B2

Patent application US20200325387A1 filed by Saudi Arabian Oil Company (SA) discloses a fracturing fluid designed to enhance hydrocarbon production comprising a base polymer and a nano-crosslinker. The nano-crosslinker comprises a base fluid, a nanomaterial and a crosslinker (carbonyl, sulfhydryl, amine, or imine), with the nanomaterial being selected from silica, cellulose, carbon-based materials, or their combinations. The base polymer, such as an acrylamide-based or polyacrylamide-based polymer, chemically bonds to the crosslinker, forming a network. The base fluid is primarily composed of water, and "…the polymer loading of the base polymer is less than 60 pounds of base polymer per thousand gallons base fluid (pptg)". The fracturing fluid system exhibits thermal stability up to 450°F and may include additional components. These components include a proppant (such as sand, clay, bauxite, alumina, and aluminosilicates) for propping open fractures, a pH control agent (e.g., potassium hydroxide, sodium hydroxide, acetic acid, various carbonates, and their combinations) to maintain the desired pH level, an antioxidant (e.g., phenols, polyphenols, hydroquinone, ethylene glycol, and others), and a clay stabilizer (e.g., sodium chloride, potassium chloride, other quaternary molecules, and their combinations).

Among the problems the invention aims to solve, the authors mention incomplete degradation of polymers at high concentration leading to a formation damage and lower conductivity of gas flow.

The patent application belongs to a family comprising 11 patent documents published in US, WO, and SA between 2016 and 2021.



Image from: US20200325387A1

High OPEX / Operation and consumables

Patent US10829683B2 by Praxair Technology Inc. (US) discloses a method of continuously producing a high-quality fracturing fluid with a high concentration of proppant. The method involves continuously supplying liquid CO2, continuously adding proppant to the stream containing liquid CO2 at a concentration of up to 20 lbs/gal, and routing the combined stream through a high-pressure pump to a well head. A second stream containing water is continuously supplied to the well head through a high-pressure pump. The two streams are mixed to form a fracture fluid with a Mitchell quality of at least 50%. Additives can be admixed to the either the two streams. The resulting fracturing fluid can have varying properties, including a Mitchell quality of about 70-90%, a 90% slurry quality, and a proppant loading of 3.75 lbs/gal.

With reference to the existing solutions, the authors mention limitations that can lead to a necessity to use a larger amount of fracturing fluid in order to place the required amount of proppant.

The family of the patent comprises 12 patent documents published in 2016-2020 in CA, US, CN, MX, AR, and RU.



Image from: US10829683B2

100 - insulated storage tank; 101 - conduit; 110 - booster pump; 111 - conduit; 120 - batch blender vessel; 121 - conduit; 130 - high pressure fracture pump; 131 - main conduit; 140 - well-head; 201 - water feed stream; 230 - high pressure fracture pump; 231 - conduit.

Patent application US20190055463A1 filed by King Fahd University of Petroleum and Minerals (KFUPM) (SA) describes a fracturing fluid composition, comprising an aqueous base fluid (for instance, seawater), a chelating agent (glutamic diacetic acid, 5-20 wt %), and "…a polymeric additive comprising a copolymer of acrylamido-tert-butyl sulfonate and partially hydrolyzed polyacrylamide, in an amount of 0.45-1 wt %", wherein "…the partially hydrolyzed polyacrylamide has a molar ratio of amide groups to carboxylate groups of 0.5 to 6". Relative to the total weight of the copolymer, acrylamido-tert-butyl sulfonate is present in the range of 5 to 20 wt %, while partially hydrolyzed polyacrylamide is in the range of 80 to 95 wt %. The resulting fracturing fluid is claimed to have "…a plastic viscosity of 2 to 8 cP at a temperature of 280 to 320° F", and "…a yield point of 2 to 15 lb/100 ft2 at a temperature of 280 to 320° F".

Among the problems of the existing solutions, the authors mention loss of fracturing fluid leading to additional production costs related to the replenishment of materials.

The patent application is a part of a family comprising 9 patent documents published in the USPTO (US) patent office between 2018 and 2019.



Image from: US20190055463A1

Ecological balance

Patent US11319482B2 published by Univar Usa, Inc. (US) on 03.05.2022 discloses a fracturing fluid composition comprising mineral oil, polyacrylamide, and guar. The composition comprises 10-90 wt.% (preferably 40-70 wt.%) of polyacrylamide in the form of a dry powder with a particle size below around 500 μm and average molecular weight of at least about 2,000,000. Further, the composition comprises 10-90 wt.% guar with a particle size below about 500 μm and a minimum solution viscosity of about 3,500 cP at 1%. Additionally, the composition includes a liquid carrier (glycol), a friction reducer (water-soluble polymer - polyacrylamide, polyethylene oxide or their combination), a cross-linking agent, an organophilic clay, and a surfactant.

The authors of the invention point out the need to develop a safe and environmentally friendly fracturing fluid with more effective friction reduction to decrease energy loss.

The patent belongs to a patent family comprising 8 documents published in 2016-2022 in the WO, CA, AR, and US patent offices.



Image from: US11319482B2

In the analysis of inventions from the pool of documents under consideration, it was found out that, in numerous cases the authors of patent documents also tend to extend their inventions to various related fields. Naturally, the most widely encountered of them is Hydraulic fracturing equipment and methods. It is followed by Drilling and well elements technology element which is explained by the fact that hydraulic fracturing fluid often can be also used as a drilling fluid. In a number of cases, hydraulic fracturing fluids are also patented along with specific proppant compositions to ensure optimum efficiency of proppant delivery.

More detailed information about inventions in the field of hydraulic fracturing technologies, and patent research methodology can be found on aenert.com, and in OIL&GAS FROM LOW PERMEABILITY PLAYS. Hydraulic Fracturing Fluids. Patent Database. Aenert. April 2021.

By the Editorial Board