It is well known that appearance of sand at the bottomhole of gas and gas-condensate wells is stipulated by different reasons related mainly to mechanical properties of the producing formation. When the reservoir pressure drops in the course of gas or gas condensate production, the gas-water contact rises leading to intensive watering out of gas and gas-condensate wells.

Motion of reservoir waters from the productive reservoir towards the bottomhole of a gas or gas-condensate well results in acceleration of the destructive processes within the formation, production of sand in the bottomhole zone, formation of a sand plug that blocks the perforation of the well and prevents the flow of gas or gas condensate to the surface up to full cessation of hydrocarbon production.

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