Preventing Aggregation of Hydrate Particles during Transient Operations with Vitamin E Succinate

Abstract

This study investigated the effect of vitamin E succinate (vitamin ES), which is environmentally benign, on its performance as a hydrate anti-agglomerant in static and transition flow operations. The inhibition performance of vitamin ES was evaluated with conventional surfactant systems, such as sorbitane monostearate (Span 60) and dodecyltrimethylammonium bromide (DTAB). Under static flow (continuous mixing) conditions, the addition of any surfactant resulted in faster nucleation compared to the absence of a surfactant (bulk water system) as a result of the formation of a water-in-oil emulsion. The addition of Span 60 resulted in a stable torque change during hydrate formation at a high mixing rate, but there was a sharp increase in torque and a risk of blocking at a low mixing rate. Moreover, the addition of vitamin ES resulted in the prevention of the agglomeration of hydrate particles along with promoting a stable torque at all mixing rates. Furthermore, vitamin ES formed a transportable hydrate slurry (containing small hydrate particles) under normal shut-in and restart conditions. The flowability of hydrate particles was maintained even during shut-in with hydrate formation and restart operations.

2022 Pioneers in Energy Research: John Ripmeester

“…Using the relative torque measurement, Kim et al identified that vitamin E succinate (vitamin ES, a biosurfactant) acts as anti-agglomerant (AA) and reduces the resistance to flow of fluid as a result of slurry-like formation during hydrate growth. In another study, the anti-agglomerating performances of 57 commercial chemicals, including cationic surfactants, zwitterionic surfactants, non-ionic surfactants, and polymers, to methane hydrate in an oil–gas–water system were evaluated using a rocking-cell apparatus …”