Wellhead desanding may increase the productivity of an oil/gas well as it opens the opportunity to a minimized choked-back production. Utilizing a wellhead desanding system upstream of the choke valve, minimizes the risk of erosion of the downstream equipment as for example; valves piping, etc. In addition, better sand separation may be achieved at high pressures due to presence of dissolved gas in the crude oil. These benefits motivated the development of the Wellhead DeSander technology as a significant improvement to conventional cyclonic desanders, gravity-based sand traps and strainers.
The novel desander system utilizes a stationary non-rotating swirl element which removes sand particles from produced multiphase fluids driven by a centrifugal force. Separated sand particles are temporarily stored in an accumulator vessel designed with an automated system that detects the level of accumulated solids and initiates the flushing procedure. In this paper the development and qualification of the Wellhead DeSander technology will be extensively described.
Case studies describing flowback operations at shale plays across the US are presented. Field data is shown demonstrating the separation performance of the Wellhead DeSander at various operating conditions such as: fluid production rates in the range of 1,500 to 14,700 Barrels Per Day (BPD), produced sand concentration upto 5 % volumetric (V/V), heavy paraffinic hydrocarbon, Gas Volume Fraction (GVF) > 90 % and watercut upto 84 %. Separation performances of the Wellhead DeSander have been measured with and without an upstream conventional sand trap. Separation efficiencies upto 99 % have been achieved with the Wellhead DeSander technology. The Wellhead DeSander can provide substantial economic benefits such as reduced erosion of a process facility and minimized operating costs with sustained optimal well productivity when solids are produced.