Effect of under-inhibition with methanol and ethylene glycol on the hydrate control process

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:434046

Yousif, M H

Hydrate control can be achieved by chemical injection. Currently, methanol and ethylene glycol are the most widely used inhibitors in offshore hydrate control operations. To achieve effective hydrate inhibition, a sufficient amount of inhibitor must be injected to shift the thermodynamic equilibrium condition for hydrate formation outside the pipeline operating pressure and temperature. Recently published field experiments showed that hydrate blockages form more readily in under-inhibited systems than in systems completely without inhibitor. A laboratory study is conducted to determine the effect of low concentration (1--5wt%) methanol and ethylene glycol on the hydrate formation process. The results show that, although these chemicals are effective hydrate inhibitors when added in sufficient quantities, they actually enhance the rate of hydrate formation when added at low concentrations to the water. Furthermore, the presence of these chemicals seems to affect the size of the forming hydrate particles.

• OSTI ID: 434046
• Report Number(s): CONF-960525--
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
CONCENTRATION RATIO
FLOW BLOCKAGE
FLUID INJECTION
GAS HYDRATES
GLYCOLS
METHANOL
MITIGATION
OFFSHORE SITES
PIPELINES
THERMODYNAMIC PROPERTIES