Patent ID: 7484562
Filing Date: 2009-02-03
Classification: E21B

Abstract:
1. A method for controlling a quantity of a specific gas in a group of gases produced from a given well bore that has access to one or both of upper seam gas and mine atmosphere in order to produce the group of gases comprising: a. monitoring an amount of a component gas in a given volume of the group of gases removed from the well bore; b. providing a control device for adjusting pressure at a well bore exit to maintain a given quantity of the specific gas; c. setting the control device to the desired quantity of the specific gas; d. controlling the pressure by the control device by adjusting the pressure of the group of gases at the exit so that the capture of upper seam gas with mine atmosphere is balanced prior to exiting the well bore to produce the desired quantity of the specific gas; e. maintaining by the control device the desired quantity of the specific gas by adjusting the pressure in response to variations of the quantity of the specific gas in the group of gases caused by changes in the balance between the upper seam gas and the mine atmosphere captured.