New testing for low dosage hydrate inhibitors withstands H2S

Offshore staff

HOUSTON -- Multi-Chem has developed the first system of advanced rocking cells for testing low dosage hydrate inhibitors (LDHIs) designed to withstand hydrogen sulfide (H₂S) gas.

The two six-cell modules are composed of the highly corrosion-resistant metal alloy HASTELLOY so that LDHI testing can be conducted using H₂S. According to the company, the system is the first of its kind and offers deepwater, ultra deepwater, and land-based operators the first opportunity to properly and safely simulate the conditions in a sour system without causing damage to the equipment.

The 12-test cells feature dual sapphire viewing windows and proximity sensors, and a center-ported configuration designed to eliminate the problems associated with more traditional end-ported designs, where hydrate formation can occur in the inlet tubing causing inaccurate results. Each individual cell window features ultra-bright rear-mounted lighting for clear viewing of the fluids.

The system’s fully automated data acquisition and control software gives users the flexibility to pre-program various testing parameters and protocol changes, including the cells’ rocking angle and rocking rate, the company says. Two large monitoring screens help to track the conditions and progress of each individual cell during the test.

“The combination of the new design features, the data acquisition system, and the quality of the materials used allows us to more accurately recreate the conditions of both sweet and sour systems as compared to other rocking cell designs,” says Zubin Patel, co-developer of the technology.

08/21/2009