Patent ID: 6705397
Filing Date: 2004-03-16
Classification: E21B

Abstract:
A system for determining a liquid level of a column of liquid contained in a well for controlling an artificial lift system for said well based on said liquid level of said column of liquid, comprising:introduction means for introducing a gas adjacent to a bottom of said column of liquid, said gas being introduced at a predetermined rate of flow so as to exhibit a predetermined negligible amount of pressure resistance due to frictional gas flow and sufficient to overcome a pressure exerted by said column of liquid adjacent to a bottom of said well; sensing means fluidly coupled to said introduction means, for sensing a liquid column pressure at which said gas overcomes said pressure exerted by said column of liquid adjacent the bottom of said well, said column of liquid exhibiting a predetermined pressure gradient; and processing means responsive to said sensing means, for determining the liquid level of said column of liquid from said pressure exerted by said column of liquid and said predetermined pressure gradient.