Choking of Oxygen Scavenger injection Quills

摘要

Chemical treatment is a primary measure for mitigating internal corrosion of process equipment at crude gathering centers as part of asset integrity management. As oxygen is highly oxidizing agent for corrosion, Oxygen Scavenger is injected to the brackish water streams to minimize the dissolved oxygen in the system and hence to mitigate corrosion. Oxygen scavenger which is 65% Ammonium bisulfite reacts with Oxygen (due to air ingress into the system) forms ammonium bisulfate. This chemical when in contact with air crystallizes at around 10°C. These temperatures can be reached in winter in the Kuwait deserts where the oxygen scavenger skids are located. This crystallization can affect the injection at the quills' end. In the present case study, many oxygen scavenger injection quills were found to be choked at the tip of the quill preventing the actual flow of chemicals to the brackish water stream. Therefore, an investigation has been conducted to identify the main root cause for choking the quills and provide remedial measures to prevent the choking.