EBI Energie Increases H2S Removal Capacity

By Paques

EBI Energie Inc. is a Canadian company that, among others, operates a landfill in St. Thomas, Quebec, where landfill gas (LFG) is converted into renewable natural gas.

In 2016, EBI upgraded its facility and installed a THIOPAQ® scrubber for gas desulfurization.

The THIOPAQ® scrubber, a very cost-effective desulfurization technology developed by PAQUES in the late 1980s, replaced an existing iron oxide media system to reduce operating costs.

The main components of EBI Energie’s THIOPAQ® scrubber system are:

– A scrubber in which H2S is absorbed from the gas into a slightly alkaline liquid. The absorption consumes some hydroxide.

– A decanter centrifuge separates the produced elemental sulfur from the process liquid, which is returned to the bioreactor.

Thanks to the resulting low caustic use, the system’s total O&M costs are very low compared to many other types of H2S removal technologies.

The THIOPAQ® installation was originally designed to treat an average LFG flow of approx. 5000 scfm, with an H2S concentration of 1,200 ppm, with a maximum H2S removal capacity of approx. 500 kg/d.

EBI’s original THIOPAQ® scrubber was designed to remove H2S to concentrations <25 ppm.

Over approximately 5 years, the LFG’s H2S concentration gradually, but significantly, increased, and in 2023, EBI decided to increase the capacity of the THIOPAQ scrubber system.

Paques provided engineering and equipment to meet the new design criteria. Major process equipment that was added were two bioreactors for converting sulfides to elemental sulfur, additional blowers and pumps, and a decanter for separating the produced elemental sulfur.

The expanded system was started in 2024. It now treats approximately 5,300 scfm LFG with approximately 4,000 ppm H2S, achieving a treated gas H2S concentration of approximately 150 ppm at a low O&M cost.

For more information, read our Canadian Biogas Magazine.