Inorganic scales are new identified phenomena in Casabe field while corrosion has started to increase to alert the field operations. The field has been under waterflooding since 1985 with no much success due to lack of vertical selectivity. It was resumed in 2004 and boosted from 25000 BWIPD to 110000 BWIPD, and in consequence, some injection related problems which had never been recognized in the field turned out to be an issue from wellbores to surface facilities. Failures in tubings, casing and flowline integrity and storage facilities with evidences of corrosion, lighted on the alarms regarding the corrosion processes in the field.

Diagnostic process started in 2010, revising the fluids being injected and the produced fluids from the wells, knowing that injected water is fresh and formation water has salinities up to 50000 ppm. Water samples were collected and analyzed to establish a current field wide corrosion baseline and evaluating the impact of the water injection process from the water source, injection lines and down into the injection wells and the reservoir, likewise the back to the producing wells x-mas trees.

Chemical treatment is being applied upfront in the injection system, and corrective treatments have been implemented in some wells to reduce corrosion downhole. Simultaneously, a surface flowline integrity survey, maintenance and replacement by new materials were initiated to avoid spills or unexpected failures in the gathering system.

Nevertheless, the current scenario is regularly under control, continuing monitoring is required in throughout the field. A new integrity management plan for the asset is under preparation since produced water is planned to be re-injected in the reservoir as primary source for the waterflooding. Whilst re-injection starts up, potential problems for corrosion could come up including scaling as it is indicated by Langelier Saturation index in the produced water.

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