5 ways to prevent H2S in sewer construction projects
Are you concerned about how hydrogen sulfide induced corrosion may impact new sewer infrastructure projects? In this insight story, we address 5 ways you can minimize the impact of the toxic gas in the planning phase of new infrastructure projects.
The only way to minimize the impact of hydrogen sulfide is to systematically include the gas as an important parameter in new construction projects. Here are 5 effective ways you can design existing or new sewer systems to mitigate hydrogen sulfide.
1. Ensure proper pipe sizing
Hydrogen sulfide is formed when wastewater is pumped in pressure pipes or stagnant wells or pipes. When designing new sewer lines, ensure the correct volume/area ratio on gravitational pipes to achieve sufficient flow. This is particularly important for separate sewer systems where the lack of stormwater significantly reduces the water flow.
2. Consider stripping the H2S
Hydrogen sulfide is transported within the sewage and is free to cause problems anywhere along a sewer line. One way of preventing the problem from being transported further downstream in the network is to ensure some degree of turbulence in discharge wells to degas the dissolved sulfide. Stripping often leads to high sulfide concentrations and odor or corrosion issues locally in discharge wells – but these challenges can be met by setting up filters or ventilation systems.
3. Set up filters or ventilation
Rotten-egg odors from high sulfide concentrations severely impact quality of life. One approach to minimizing odors is to set up filters or ventilation systems. Filter systems include clamshell filters, activated carbon filters, biomats, and other filter solutions.
4. Choose corrosion-resistant pipe materials
Hydrogen sulfide induced corrosion causes concrete pipes and wells to break down prematurely. A simple solution to this problem is to select corrosion-resistant materials or liners. HDPE pipes do not rust, corrode or rot.
It is important to note, that by choosing corrosion resistant pipes, there is a risk that hydrogen sulfide problems are transported downstream in the sewer network. And by doing so, there is a risk taht odor and corrosion events may occur in other locations.
5. Construct sacrificial pipes
Another approach to the hydrogen sulfide challenge would be to accept it and construct sacrificial pipes at known sulfide hotspots near critical infrastructure.