Engineering Aspects of the Downhole Gas Separator

Abstract

Placement of a full size downhole gas separator in a geothermal well is not considered a highly complicated engineering exercise. problems and inconvenience occur later when the system is running and when well maintenance is required. The preferred system is when the separator is fixed in the casing and the tubing carrying the extracted gas is allowed to expand through a gland at the wellhead. All considered options of placing the separator precluded the use of downhole measurement instruments and more importantly monitoring of deposition buildup in the production zone. At the time of writing no clear evidence was available to determine the exact level of deposition in any one well nor what affect the separator itself had on the level of deposition. The estimate for placing the DHS in 1984 was $182200 the cost of removal $80000 and the cost of replacement $140000. An annual workover to calcite above and below the DHS, which would include replacement, was to cost $297000 without the cost of a new DHS.