Technology of well kick-off with nitrogen units is used in case of necessity to decrease back pressure on reservoir, caused by presence of killing fluid or drilling mud in the well after drilling or workover operations. These operations are performed for inflow stimulation in oil and gas wells.
KazGeoTech offers 2 types of nitrogen units that differ from each other not only by their technical characteristics, but also by the way they are used in coiled tubing operations
- Nitrogen compressor station (or membrane nitrogen unit) equipped with separation membranes (manufactured by Tegas, Russian Federation) with maximum nitrogen gas supply up to 10 scm/min and maximum operating pressure up to 250 bar.
As you know, nitrogen makes up 78% of the total volume of air. When compressing, the unit uses the nitrogen in the air by separating it from oxygen, making it suitable for continuous nitrogen injection, in shallow wells (up to about 2,500 m), and for purging of various surface equipment.
- Nitrogen cryogenic unit equipped with a cryogenic gasifier with a maximum flow of gaseous nitrogen of 85 m3/min and a maximum operating pressure up to 700 bar. This unit uses nitrogen delivered to a well in a liquid state with a temperature below -196°C. When heated, nitrogen transforms into gaseous state and expands 694 times. Further, a special pump of the nitrogen unit pumps nitrogen into the well at high speed and pressure, allowing to develop wells with the depth of up to 7000 m. This nitrogen unit is also used for nitriding fluids, reducing hydrostatic pressure, and creating underbalanced shelfs during development, foaming special blowing agents , and many other more complex inflow stimulation operations.
