Application Note

Steam Custody Transfer

Source: McCrometer, Inc.

By McCrometer, Inc.

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Steam Custody Transfer between a cogeneration plant and an operator. The oil field operator injects the steam into the ground to heat the heavy (API gravity 6-15 typically) oil. Once heated the oil can be retrieved via traditional pumping methods. The operator pays for the steam by the BTU at the negotiated point of custody transfer. The cogeneration plant guarantees a pressure and quality at that point. Verification of quality is done periodically using a surface separator.

A 4” V-Cone provides sufficient flow turndown to meet the varied rates (nom. 4000 barrels of steam per day CWE in this case). In addition to this, wear is not a problem and accuracy is insured over the long run without yearly primary element replacement. As an added benefit, the V-Cone has less of a measurement shift in a potentially two phase flow environment (water/vapor) than traditional flow elements. The steam quality seen in this application is typically between 90 and 100 percent. Lower steam qualities are seen at the injectors.