Joint Industry Program to Model Sour Well Environments

The Southwest Research Institute (SwRI) (San Antonio, Texas, USA), in collaboration with OLI Systems Inc., has launched phase one of its “In Situ Measurement of Hydrogen Sulfide to Validate Thermodynamic Calculations” joint industry program (JIP) to more accurately model the environments in sour wells. 

In turn, they hope to improve the qualifications of alloys used in harsh operating conditions.

Deeper wells containing hydrogen sulfide (H2S), known as sour wells, are being explored by oil and gas operators. The combination of higher pressure and temperatures, as a result of the wells’ depth and acidity due to the presence of (H2S), make those wells particularly challenging when it comes to materials. 

As a result, the industry uses expensive corrosion-resistant alloys during exploration and production. The alloys are qualified using combinations of documented field experience and laboratory testing, but a recent review of the chemistry of sour wells suggest that the environmental test conditions are harsher than required. Thus, the industry could save millions of dollars on the alloys used to withstand these conditions.

“The aim of SwRI’s JIP is to create a new, more accurate model of the conditions of sour wells,” says Florent Bocher, a senior research engineer and project leader. “We will learn more about the chemistry of these wells at high pressure and temperatures. To accomplish this, we will use existing SwRI equipment to make measurements of hydrogen sulfide in the gas and liquid phases at the pressures and temperatures that exist in sour wells.”

During the one-year first phase, an experimental matrix will be generated at the intersection of the industry needs, model limitations, and lack of data, with a goal of validating in situ analytical techniques.

In phase two, in situ H2S measurements will be performed over that matrix. The results of those measurements will be implemented into the modeling software to offer a more accurate and reliable model. This, in turn, could reduce the need for expensive materials.

Though the first phase began earlier this year, the JIP is still accepting members. During this phase, Bocher plans to collaborate with SwRI’s chemistry and chemical engineering division to recreate the conditions of sour wells in collaboration with OLI Systems, who will contribute modeling expertise. 

Testing will begin in the second phase, with the project reaching completion in 2026.

Source: SwRI,