Application of Chemistry in Oil and Gas Well Fracturing

Harms, W.M.

doi:10.1021/bk-1989-0396.ch002

Cited by 19 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[1][2][3] are presented for borate-crosslinked Guar and hydroxypropyl Guar (HPG) for a range of fracture shear rates (approximately 20-200 sec -1 ), pH, and temperatures, typically encountered in hydraulic fracturing treatments. [1][2][3] are presented for borate-crosslinked Guar and hydroxypropyl Guar (HPG) for a range of fracture shear rates (approximately 20-200 sec -1 ), pH, and temperatures, typically encountered in hydraulic fracturing treatments.…”

Section: Resultsmentioning

confidence: 99%

“…1 Borate-crosslinked gels were initially popular because high viscosity fracturing fluids could be easily generated using a relatively inexpensive and naturally occurring borate compound. 1 Borate-crosslinked gels were initially popular because high viscosity fracturing fluids could be easily generated using a relatively inexpensive and naturally occurring borate compound.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Borate-Crosslinked Fluid Rheology Under Various pH, Temperature, and Shear History Conditions

Shah

Lord

Rao

1997

SPE Production Operations Symposium

View full text Add to dashboard Cite

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractThe oil and gas industry has now long been aware of the fact that the rheological characterization of crosslinked fluids under field simulated conditions is very difficult. Particularly, the testing of borate-crosslinked fluids under realistic conditions for better understanding of their rheological behavior, is very complex. For this purpose, the Gas Research Institute (GRI), the U. S. Department of Energy (DOE), and the University of Oklahoma jointly established the Fracturing Fluid Characterization Facility (FFCF) which includes a pilotplant scale, high temperature, high-pressure simulator (HPS) coupled with a fluid pre-conditioning system. Employing the field-size equipment of the FFCF and field-simulated procedure, various borate-crosslinked fluid formulations are tested and evaluated for their rheological responses. This paper presents the results of pre-conditioned fluid rheology tests conducted with borate-crosslinked Guar and HPG gels employing the HPS over a range of pH from 9 through 11, subjected to varying levels of shear history and temperature. The network structure of these crosslinked fluids at any time is dependent on the current shear state, past shear history, and borate ion concentration which in turn depends on pH and temperature. Even though the effect of pH and temperature on the borate ion concentration is relatively well understood, the characterization of the shear state of the gel at field conditions is still in its infancy. In this investigation, test fluids are subjected to all conditions, to the maximum degree practical, experienced by a fracturing fluid in the field, including its formulation in surface equipment, its injection through tubular goods and perforations, and its flow and heatup in the fracture. Besides the effects of polymer type, temperature, and fluid pH, the effects of shear history on the rheology of borate-crosslinked fluids are also investigated. The presented results show dramatic effects of shear history on the rheology of borate-crosslinked gels which have been ignored in previous investigations. Certain gel formulations corresponding to specific pH and temperature conditions, were found to be shear history insensitive. Furthermore, these shear history insensitive formulations were also found to exhibit an optimum viscosity which was independent of temperature over the range of ambient to 185 F.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Borate-Crosslinked Fluid Rheology Under Various pH, Temperature, and Shear History Conditions

Shah

Lord

Rao

1997

SPE Production Operations Symposium

View full text Add to dashboard Cite

show abstract

“…Gelled hydrocarbons remained the preferred fracturing fluids for about 10 years. These fluids could carry moderate volumes of proppant (1 to 3 lb/gal) and viscosity could be adjusted by changing the oil used or varying the concentration of gelling agent (Harms 1989). Hydrocarbons used included kerosene, diesel No.…”

Section: Hydrocarbon-base Fluidmentioning

confidence: 99%

“…Guar and its derivatives remain the most-used gelling agents for viscosifying water-based fracturing fluid. Cellulose polymer and its derivatives are preferred over guar when preparing viscous acids or brines; this group includes carboxymethyl cellulose and xanthan (Harms 1989).…”

Section: Gelling Agentsmentioning

confidence: 99%

Dry-Polymer Blending Eliminates Need for Hydrocarbon Carrier Fluids

2009

View full text Add to dashboard Cite

This paper presents methods, materials, and equipment that can be used to mix and apply viscous proppant-carrying fluids, on-the-fly, to support hydraulic fracturing processes using a dry-polymer blender. This dry-polymer blending system (DPBS) replaces the liquid-gel concentrate (LGC) mixing method, which requires premixing gel-producing powders with a hydrocarbon carrier fluid.The equipment and methods described have contributed to a cleaner environment without imposing any cost increases or wellsite expansion on the operating company. The on-the-fly dry-gel blending process is compatible with existing fracturing technology, and has helped enable environmentally responsible technology development.The fracturing fluid product used in this process is based on dry powders and does not contain hydrocarbon carrier fluids. Dry-polymer blending enables the use of new gel systems that work well in produced waters. This type of blending can be applied in any hydraulic fracturing operation requiring preparation, blending, and pumping of a viscous fluid to suspend proppant for transport to created fractures. The DPBS uses a trailer with a weigh system and continuous viscosity monitoring to help ensure job quality. Handling of the gel powder can be accomplished without dusting.

show abstract

“…These fluids can be divided into two main groups, namely oil-based and water-based fracturing fluids. Oil-based fracturing fluids are gasoline gelled with aluminum carboxylates, soaps, viscous refined oils, phosphate esters or gelled crude emulsions [ 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. They were used to prevent damage to formations containing water-sensitive clays.…”

Section: Introductionmentioning

confidence: 99%

Insights on Potential Formation Damage Mechanisms Associated with the Use of Gel Breakers in Hydraulic Fracturing

Almubarak

AlKhaldi

et al. 2020

Polymers

View full text Add to dashboard Cite

Hydraulic fracturing using water-soluble polymers has been extensively used to enhance the productivity of oil and gas wells. However, the production enhancement can be significantly impaired due to polymer residue generated within the proppant pack in the created fractures. This work describes an approach to establish a suitable fracturing fluid cleanup process by characterizing broken polymer residues generated from the use of different gel breaker types. Commonly used gel breakers such as inorganic oxidizers (bromate and persulfate salts), specific enzymes, and acids were evaluated in this work. The influence of each gel breaker was examined using High-Pressure/High-Temperature (HP/HT) rheometer, aging cells, zeta potential, Gel Permeation Chromatography (GPC), and Environmental Scanning Electron Microscope/Energy Dispersive X-ray Spectroscopy (ESEM/EDS). Experiments were performed on a carboxymethylhydroxypropyl guar (CMHPG) fracturing fluid at temperatures up to 300 °F. The developed GPC methodology showed that the size of the broken polymer chains was mainly dependent on the type of gel breakers used. Moreover, laboratory tests have revealed that some gel breakers may negatively influence the performance of polymeric clay stabilizers. Additionally, this work showed damaging precipitations that can be generated due to the interactions of gel breakers with H2S.

show abstract

Application of Chemistry in Oil and Gas Well Fracturing

Cited by 19 publications

References 0 publications

Borate-Crosslinked Fluid Rheology Under Various pH, Temperature, and Shear History Conditions

Borate-Crosslinked Fluid Rheology Under Various pH, Temperature, and Shear History Conditions

Dry-Polymer Blending Eliminates Need for Hydrocarbon Carrier Fluids

Insights on Potential Formation Damage Mechanisms Associated with the Use of Gel Breakers in Hydraulic Fracturing

Contact Info

Product

Resources

About