Presently, gas hydrates formation pose problems, causing flow restrictions, in gas and oil industry including drilling operations (particularly in deep water), production process, well workovers where gas and water come into contact at equilibrium conditions. Traditional hydrate control methods of insulation and/or thermodynamic or chemical inhibition may not provide the desired level of hydrate protection at an economic price. Low-Dosage Hydrate Inhibitors (LDHIs) are a proven technology to control hydrates in numerous applications and are instrumental in reducing the total cost of operations. Low dosage Inhibitors are either kinetic, thermodynamic inhibitors or anti- aglomerants, which either prevent hydrate formation or remove the hydrates that are already formed respectively.
Therefore, this paper focuses on introduction to such low dosage inhibitor which can perform all the functions like prevention of formation of hydrate nuclei (like kinetic or thermodynamic inhibitors) and dispersing the already formed ones in flowlines (like anti- agglomerants). This paper proposes the use of Cationic polymers like cationic starch (from a high amylose carbohydrate source) in low concentration with addition of Polyethylene Oxide (PEO) as a new Gas Hydrates inhibitor.
The polymer with PEO, dissolved in water, can be introduced in petroleum fluid using mechanical equipment or utilized in treating fluid prior to substantial formation of the hydrates. As observed from an experimental analysis, these positively charged polymers interfere with nucleation of hydrates, increase induction time of gas hydrate nucleation, suppress memory effect, and act as antifreeze and thereby controlling hydrates.
With reference to these polymers, their abundant availability, easy application techniques and simple cationization procedure all contribute to its inexpensive and environment friendly usage as gas hydrate inhibitor. This paper provides systematic approach and relevant theoretical explanation for the proposed technique.