Efficient H2S Scavenging Using Chemical Management System

Often known as “rotten egg” gas due to its characteristic odor, H2S is a deadly gas capable of killing within minutes of exposure. It is regularly encountered in upstream oil and gas operations. This low-lying gas found in wells, pipelines, and storage tanks is produced by the bacterial decomposition of the organic matter found in crude oil.

The oil industry uses chemicals to prevent or treat H2S build-ups. In order to prevent the production of H2S in wells, biocides can be injected to kill the bacteria that produces it. When there is already H2S accumulated in wells, it can be neutralized through chemical reaction using H2S scavengers.

In the past, E&P (Exploration & Production) companies did not know how much H2S scavenger to inject in a well that detected H2S. The injection process was not automatic and the injection rate did not vary on-the-fly with the varying concentration of H2S in the well. This resulted in hazardous conditions when too little or no H2S scavenger was injected. On the other hand, when too much H2S scavenger was injected, the costs soon exceeded the operating budget.

Chemical management systems (CMS) like Profire’s PC180 have optimized and automated H2S scavenging operations. The PC180 electronic control system constantly monitors the H2S levels in the well. If it exceeds the acceptable threshold, the rate of H2S scavenger injection is increased proportionally. While if it goes below that threshold, the rate is decreased accordingly. The figure below summarizes how H2S scavenging works using the PC180.

Through a Modbus connection, the PC180 can be operated remotely using a SCADA (Supervisory Control And Data Acquisition) system. This enables the operators to override settings and control injection rates without exposing themselves to the hazards of H2S affected well sites. It also reduces transportation cost and extra time as visits to the well site are reduced.

All E&P operators are interested in keeping within budget while ensuring smooth and safe operations. Using a CMS like the PC180, objectives can be achieved by eliminating H2S from wells in the most efficient manner.

Profire Energy offers PC180 CMS solutions. Using the PC180 system, you can reap all the advantages of automated chemical management that have been discussed above. To learn more about our products and solutions visit www.profireenergy.com .