Effect of Type of Hydrates on Inhibiton consumption

[Sawsan311]

Dear All,

In case hydrates are depicted by simulation software that it can form under the stream's conditions while showing hydrate type as type I. knowing that hydrate type I are relatively less stable than the other hydrates type like II and H, would this contribute in reducing the requirement of methanol inhibitor in l/hr?

thanks

 

[apetri]

for many natural gas mixtures, both hydrate structures I and II can form,
(as simple hydrates, C1, C2, CO2, H2S form structure I while N2, C3, NC4 form structure II etc.),
as general rule, given a temperature, structures II can form at lower pressure than I ,
the presence of thermodynamic inhibitors such as alcohols (as methanol) or glycols causes a change in phase equilibria and the contribute can be evaluated solving a multiphase flash operation at some specified conditions,
another option is the Hammerschmidt equation or similar methods,
to define the amount of inhibitors I compare the results from multiphase flash (solved with Prode) with other methods and experimental results,
note that comparing different methods you can expect quite large differencies when inhibitor / water weight fraction > 0.3-0.4