Kinetic Hydrate Inhibitors (KHI) is added to the produced fluids in oil and gas fields. Hydrate formation is a major flow assurance issue and the petroleum industry spends millions of dollars annually in this area. Kinetic inhibitors act as anti-nucleator and delay the formation of gas hydrates. The advantages of these chemicals that they are more economical and added at a low dosage without disturbing the pipeline flow. Globally, different proprietary KHI compounds are used in various locations. One specific KHI was used in the present work. Considering that produced water containing KHI may have negative impact on the environment during discharge, efficient treatment solutions to remove KHI are needed. The objective of the present laboratory investigation is to address the various treatment methods, namely membrane process and advanced oxidation process for removal of KHI. These treatment processes have huge potential to be implemented in the oil & gas industry for environmental sustainability.
Membrane processes based on Ultrafiltration (UF), Nanofiltration (NF) and Reverse osmosis (RO) were investigated using synthetic produced water containing KHI. The experiments were carried out using a bench scale membrane unit. The removal efficiency of KHI was found to be greater than 99%, 99%, and 83% for RO, NF & UF membrane, respectively.
The chemical process based on ozonation was also investigated. The ozone effectively degraded 75% of KHI polymer with ozone dosage of 0.73 g/h. The extent of oxidation of KHI is dosage/time dependent. To the author's knowledge, this is the first work reported in the literature regarding KHI removal by membrane technology and advanced oxidation.