Split-fluid fracturing uses two fluid streams, (1) a highly concentrated slurry and (2) a clean fluid, sent to separate groups of high-pressure pumps, which is an alternative to the traditional method of supplying a lower-concentration slurry to all highpressure pumps. Reducing the number of high-pressure pumps exposed to abrasive slurries extends pump and manifoldequipment life. Centrifugal pumps at the fracturing-fluid supply send water to the blender and also boost the clean fluid highpressure pumps directly. Chemical additives, such as friction reducers, can be added to the clean fluid. The highly concentrated slurry and the clean fluid are mixed together in the high-pressure manifold. The resulting fluid-proppant concentration is monitored by a high-pressure densometer. Updated blender operating software combines input from flow meters monitoring the two fluid streams to determine a real-time combined fluid rate. Chemical additive and proppant rates are adjusted by the blender software so that the combined fluid meets the fracturing job-design specifications. Field trials were conducted to determine the effectiveness of this method along with variations to the method, such as mounting the clean fluid-supply boost pumps onto the high-pressure manifold trailer.

This method has been successful in waterfrac market areas using low proppant concentrations (0.5-lbm/gal concentration on the majority of jobs), high water volumes (more than 3,000 barrels), and high-rate (more than 50 bbl/min) fracturing treatments.

Maintenance costs were dramatically reduced while fracturing treatments were delivered to the operator as designed with increased reliability of pumping equipment and no lost time.

Fracturing equipment service operators and well operators both benefited from reduced operational costs and the increased reliability of the pumping equipment. Additionally, reducing the amount of back-up fracturing equipment required helped reduce the equipment footprint on location.

You can access this article if you purchase or spend a download.