Recent Advances in Waterless Fracturing Fluids: A Review

Abstract

Hydraulic fracturing technology has grown popular with the rapidly increasing development of tight conventional and unconventional reservoirs. A major concern with this technique is the use of large amounts of water in these treatments. The use of water causes many potential damaging issues in the formation and limits the amount that can be saved for future generations. One solution is waterless fracturing treatments, which were developed to reduce or eliminate the need for water in hydraulic fracturing. Hydraulic fracturing treatments consume at least 200,000 gallons of water in conventional wells and up to 16,000,000 gallons of water in unconventional wells. The pumped water must include clay stabilizers to deal with the sensitive clays in the formation. Additionally, using water poses a risk of inorganic scale precipitation near the wellbore. Water can also cause severe emulsions that can lead to emulsion blockage cases. Moreover, there are significant reports of water blockage cases in tight gas wells. Only a mere 10-30% of pumped water flows back after the treatment, with the rest attached to clays, or stuck in the pores due to high capillary pressures. Water-based fluids can also cause alterations to relative permeability, and liquid holdup cases in many gas wells. These issues can certainly increase near wellbore skin and reduce production rates. At the end of the treatment, water still causes issues related to disposal and separation prior to diverting it to the plant. The main challenges in developing waterless fluids include feasibility, environmental friendliness, and effectiveness to stimulate the reservoir. This review will cover the various waterless fracturing methods such as hydrocarbon-based, liquid CO2, energized, and foamed fluids (CO2 and N2 foams) as well as their advantages and disadvantages. Studies into the properties of these fluids, such as rheology, solubility, compatibility, will also be discussed. Field trials will be examined where applicable. This literature review examines various waterless alternatives to traditional fluids for hydraulic fracturing. From this paper, readers can better understand the nature of waterless technologies and be able to better evaluate these technologies for fracturing purposes.

Insights into CO2 Foaming Behavior of Ethoxylated Amines

“…Ostwald ripening is a thermodynamically driven mechanism occurring due to larger particles being more energetically favored than smaller particles in a heterogeneous system like foam. After the foam formation, the smaller foam bubbles shrink while the bigger ones grow over time [26,27]. Due to big foam bubbles being generally less stable, Ostwald ripening leads to the overall foam system instability.…”

Multiphase Multicomponent Numerical Modeling for Hydraulic Fracturing with N-Heptane for Efficient Stimulation in a Tight Gas Reservoir of Germany

“…At this point, it is important to address the economic considerations regarding the field application of n-heptane (or light alkanes) as a frac-fluid. Studies for the application of hydrocarbon-based fluids have demonstrated economically attractive prospects and shown that comparable or even lower costs will be incurred in comparison with waterbased fluids due to lower well cleanup requirements, better flowback ability, less additives, injection fluid flowback, reuse or sale, no special disposal requirements, and increased productivity [22,[55][56][57][58][59][60]. Moreover, unlike gas-based hydrocarbon fluids such as LPG, there is no need for compression for liquification for the fluid reuse [61].…”

Seawater-Based Fracturing Fluid: A Review

“…Obtaining fresh water has become difficult in some fields due to the high water transportation costs from the source to the wellsite, as well as rising limits on freshwater supply . Conventional wells use 200 000 gallons of water for hydraulic fracturing, while unconventional wells can use up to 16 million gallons. − For example, fracturing shale and tight sandstone formations often require more than 1 million gallons (3700 m 3 ) of water per well . This method uses a lot of water, damages the formation, and restricts future savings.…”

“…Therefore, it is vital to examine alternatives to water-based fracturing fluids that support the preservation of water and encourage sustainable growth. Waterless hydraulic fracturing procedures can reduce or eliminate water use . It has become essential to find ways to optimize hydraulic fracturing operations in order to utilize less fresh water and more green additives.…”