Abstract: An artificial lift system for use in a well bore including at least one chamber having an inlet and an outlet, a power gas string in valved communication with the chamber, a liquid string in valved communication with the outlet of the chamber, a vent in valved communication with the chamber and in valved communication with the liquid string at a location above the chamber, a compressor connected to the power gas string and adapted to pass a pressurized gas into the power gas string, and a valve connected to the power gas string and to the chamber the adapted to selectively allow the pressurized gas to enter the chamber so as to cause a liquid in the chamber to pass through the outlet of the chamber and into the liquid string. The vent has a check valve connected to the liquid string and adapted to pass a portion of the vented gas into the liquid string. The liquid extends continuously as an ungasified liquid along the liquid string from the outlet to the check valve between the vent and the liquid string.

Abstract: An artificial lift system for use in a well bore including at least one chamber having an inlet and an outlet, a power gas string in valved communication with the chamber, a liquid string in valved communication with the outlet of the chamber, at least one vent in valved communication with the chamber and adapted to pass a vented gas from the chamber, a compressor connected to the power gas string and adapted to pass a pressurized gas into the power gas string, and a valve connected to the power gas string and to the chamber. The vent is connected to the compressor and is adapted to pass the vented gas into the compressor. The valve is adapted to selectively allow the pressurized gas to enter the chamber so as to cause a liquid in the chamber to pass through the outlet of the chamber and into the liquid string. A first vent is in valved communication with the chamber and is connected to a stage of the compressor.

Abstract: An artificial lift system for use in a well bore having a first chamber with an inlet and an outlet, a second chamber having an inlet and an outlet and arranged in spaced and separate side-by-side parallel relationship to the first chamber, a power gas string connected to the first and second chambers, a liquid string connected to the outlet of the first chamber and to the outlet of the second chamber, a vent connected to the first and second chambers, a compressor connected to the power gas string and adapted to pass a pressurized gas into the power gas string, and a valve connected to the power gas string and to the vent. The valve is adapted to selectively and alternately pass pressurized gas into the first and second chambers so as to cause liquid in the first and second chambers to pass through the respective outlets and into the liquid string. The valve is adapted to selectively and alternately vent gas from the first and second chambers after the liquid has passed into the liquid string.

Abstract: A double acting artificial lift system for use in a wellbore having two chambers, each having an inlet and outlet; a power gas string connected to both chambers; a liquid string connected to the outlets of both chambers; a vent connected to each chamber for selectively allowing a gas to pass outwardly of the chamber; and a double acting valve connected to the power gas string and the vents. The valve alternately allows the pressurized gas into each chamber, while venting the other chamber. The pressurized gas enters the chambers to cause any liquid in the chambers to pass through the outlet and into the liquid string such that the liquid extends continuously along the entire length of the liquid string. The venting allows the chambers to fill with liquid from the wellbore.