RIASSUNTO
Abstract
A successful field trial of velocity-string technology was recently completed on a standing gas well with high condensate-gas ratio (CGR) in Saudi Arabia. The operation was performed in three attempts, and it included running a 10,000-ft-long, 2 3/8-in. outside diameter (OD) coiled tubing velocity string hung inside the existing 4 1/2-in. production tubing using a mechanical packer/hanger. To comply with the pressure barrier policy ((i.e. API 16ST) operations, the lower bottomhole assembly (BHA) included retrievable cartridges with double-flapper check valves, which were retrieved later using slickline. Both Saudi Aramco and the service company faced several serious challenges during this operation, which required three running attempts and also modifications to packer/hanger construction. Some of the procedures were changed, as well, to address the encountered complications. A test separator was used to measure the flow at surface prior to and after the velocity-string installation for evaluation of results. This standing well was revived after being dead for 2 years, and it was put back on production with more than 5 MMscf/D at flowing wellhead pressure (FWHP) of 1,900 psig, condensate rate in order of 1,000 B/D, and water rate less than 100 B/D. The velocity-string approach has proved to be a cost-effective solution for Saudi Aramco gas wells with a condensate banking problem, and the velocity-string approach is planned for several well candidates in the next 2 yr.