Title : Formation of pseudo-scale due to incompatible field chemical at oil and gas field water pipelines
Abstract:
Oil field chemical compatibility consider one of the most important factors that can affect water quality at oil field, utilization of compatible field chemicals such as (Scale inhibitor, corrosion inhibitor, oxygen scavenger and Biocide) can lead to smooth operation and protect the pipeline internal surface from corrosion and scale formation.in this research we have studied the formation of pseudo scale due to side reaction of incompatible scale inhibitor with amine-based corrosion inhibitor at high saline sour field formation water. Thoroughly investigation was conducted to understand the formation of undesirable deposits at formation water pipeline which can cause blockage of valves and strainers for different types of scale inhibitor (Phosphate base and polymer base) with amine base corrosion inhibitors. Process simulation was conducted at laboratory by injecting each field chemicals separately and combined to untreated formation water and it was observed that formation of white precipitation after dosing scale inhibitor and corrosion inhibitor at all concentrations. The reaction was tracked by advanced instrument such as Agilent Gas chromatography by observing the reduction of methanol peak by 80% with reaction progress, Agilent Gas Chromatography mass spectroscopy confirmed the polyamide compound at the formed precipitations and FTIR to find that the formed aggregates are polyamides polymer which was formed due to reaction of polyacrylamide scale inhibitor and methanol/glycol which is the major constituents in corrosion inhibitor. Several scale inhibitor types were tested until found that only phosphate-based type is compatible with water geochemistry and other injected field chemical.
