Some oilfield operators have experienced a marked increase in steam generator catastrophic tube failures due to changes in water quality reaching the steam generators and aging of the steam generators. One operator in the South Belridge Field has been replacing one-third to one-half of the radiant tubes in each steam generator every year for several years. In addition, some operators have been limited trying to increase steam generator throughput by both the steam generator's design and other interrelated facilities. Minor piping and control system changes allow the conversion of a typical 50MMBtu/hr steam generator's radiant heat recovery section from a design of one (l) single water/steam pass to a design of two (2) parallel water/steam passes. The result is that the water/steam mixture has half the distance to traverse in the radiant section and does so at half the velocity. The water quality problem or steam generator aging problem seems to benefit from the reduced velocity since no tube wall loss has been detected in six (6) months on steam generators receiving this change. In addition, since pressure loss depends on length and velocity to the second and third powers, lower pressure drop in the radiant section has allowed significant increases in steam generator throughput thus lowering unit steam costs. Here a simple mechanical change in the steam generator provided a solution that was uneconomical to address chemically or with other facilities.

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