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Fracturing Fluids
Water is the driving fluid used in the hydraulic fracturing process. Depending upon
the characteristics of the well and the rock being fractured a few million gallons of
water can be required to complete a hydraulic fracturing job.
When the water is pumped into the well the entire length of the well is not
pressurized. Instead, plugs are inserted to isolate the portion of well where the
fractures are desired. Only this section of the well receives the full force of pumping.
As pressure builds up in this portion of the well, water opens fractures, and the
driving pressure extends the fractures deep into the rock unit. When pumping stops
these fractures quickly snap closed and the water used to open them is pushed back
into the borehole, back up the well and is collected at the surface. The water returned
to the surface is a mixture of the water injected and pore water that has been trapped
in the rock unit for millions of years. The pore water is usually a brine with
significant amounts of dissolved solids.
Chemicals are often added to the water used in hydraulic fracturing. These
additives serve a variety of purposes. Some thicken the water into a gel that is more
effective at opening fractures and carrying proppants deep into the rock unit. Other
chemicals are added to: reduce friction, keep rock debris suspended in the liquid,
prevent corrosion of equipment, kill bacteria, control pH and other functions.
Most companies have been resistant to revealing the composition of their
hydraulic fracturing fluids. They believe that this information should be kept private
to protect their competitive research. However, regulators are starting to demand the
information and some companies are starting to share the information voluntarily.

Proppants
A variety of proppants are used in hydraulic fracturing. These are small
crushresistant particles that are carried into the fractures by the hydraulic fracturing
fluid. When the pumps are turned off and the fractures collapse these crush-resistant
particles hold the fracture open, creating pore space through which natural gas can
travel to the well.
Frac sand is the proppant most commonly used today but aluminum beads,

ceramic beads, sintered bauxite and other materials have also been used. Over one
million pounds of proppants can be used while fracturing a single well.

15 Translate the following texts into English using a dictionary.
ФОНТАННА АРМАТУРА

Фонтанна арматура – устаткування гирла фонтанної нафтової і
газової свердловин, яке включає трубну головку, фонтанну ялинку, запірні та
регулювальні пристрої і призначене для герметизації гирла свердловини,
контролю і регулюванню режиму їх експлуатації, а також для проведення
різних технологічних операцій.
Монтується на гирлі фонтанної свердловини для його герметизації,
підвішування ліфтових труб, керування потоками продукції свердловини,
контролю і регулюванню режиму їх експлуатації, а також для проведення

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