Phase splitting at piping junctions in two-phase steam distribution systems results in unequal steam delivery to injection wellheads and interferes with the optimization of injection rates. Texaco's researchers have investigated phase splitting and have devised and evaluated various methods for its mitigation. As a result of these efforts, the SpliTigatorTM, a device for the mitigation of phase splitting, was developed and patented.
The SpliTigator is designed to deliver a specific steam quality to the branch leg of a Tee junction. The SpliTigator delivers consistent steam quality as branch flow rate, system pressure, and inlet flow conditions change. SpliTigator pressure losses are small, allowing numerous devices to be used in series. The use of the SpliTigator has been extended to flow rate and steam quality measurement and other two-phase systems. This paper presents an explanation for phase splitting, discusses the theory behind the design and operation of a SpliTigator, and presents results from both laboratory testing and field applications.
The phase splitting behavior which commonly occurs at piping junctions within two-phase piping systems results in unequal distribution of the phases between branches of the junction. In steam distribution systems, inequitable phase splitting results in the delivery of a wide range of steam qualities and mass flow rates to injector wellheads. The SpliTigator is an effective and inexpensive device for the mitigation of phase splitting that has been developed through the joint efforts of Texaco personnel at the Bakersfield Division's Kern River Business Unit and at the Exploration Production Technology Division's Steam Flow Research Facility. An isometric diagram of a SpliTigator is shown in Figure 1. The following summarizes the most significant features of the device.
Controls branch steam quality within a few quality points of design over a wide range branch flow rates, system pressure, and trunk line steam quality.
Creates no additional pressure drop in the main line and requires very little pressure drop in the branch for effective operation.
Requires no moving parts, no periodic adjustments, and little or no maintenance throughout the life of the steam flood.
Is constructed from off-the-shelf piping components as a drop-in replacement for existing branch Tee junctions.