At the root of most odors generated from wastewater operations is When organic matter decomposes anaerobically (without oxygen), sulfur compounds are converted in hydrogen sulfide (H2S), which is a foul smelling, noxious, corrosive and flammable gas. This can occur in water where the hydrosulfide ions (HS-) are produced in solution and carried along until the outgas as H2S, creating the familiar rotten egg stench.
Exposure to hydrogen sulfide may cause irritation to the eyes and respiratory system. It can also cause apnea, coma, convulsions, dizziness, headache, weakness, irritability, insomnia and stomach issues. (Source – CDC)

Additionally, H2S is a major cause of odors in wastewater treatment systems and is notable for its toxicity and its ability to corrode various materials used in sewer and treatment plant construction. (Source – EPA)
Much effort and many technologies have been developed and applied to combat H2S in both aqueous and gas phases, with varying degrees of expense, effectiveness, and side effects.
One particularly effective method of treating H2S in solution is Liquid Redox. While normally associated with treating H2S as a gas, liquid redox catalyst can be applied in the aqueous phase in combination with hydrogen peroxide to effectively and economically reduce dissolved sulfides and eliminating H2S odor problems.
We cover Liquid Redox and other H2S treatment methods in our White Paper Wastewater Odor Control Technology and Best Practices.
The key to the success of liquid redox treatment is the regenerative nature of the reaction. It starts with a chelated (pronounced: key-late-ed) iron catalyst that has a strong affinity for the hydrogen atom in the hydrosulfide ion that destroys the sulfide, leaving elemental sulfur. If the process stopped right there, it would be neither effective nor economical because the volume of catalyst would need to match the volume of sulfides.
However, it does not stop there. The second part is introducing hydrogen peroxide, an effective means of delivering oxygen in water, reacts with the reduced catalyst by taking the hydrogen and thus reactivating the chelated iron to react with yet another HS- ion. This process continues until either all the oxygen is consumed or all the HS- is destroyed.
The first part of the reaction is called “reduction”, the sulfide is reduced, and the reactivation of the catalyst is “oxidation”, the catalyst is oxidized. The whole process together is known as “Liquid Redox”.
There are several benefits to using Liquid Redox:
- First, it works. High sulfides can be treated to non-detect levels, reducing odor and damage to pipes and equipment.
- Second, while more expensive than competitive chemical on a per gallon basis, the fact that the same catalyst reacts again and again with sulfides, less chemicals are required making Liquid Redox more economical from a total cost of treatment perspective.
- Third, Streamline’s liquid redox catalyst is safe to handle and transport and is a green biodegradable technology with no harmful byproducts.
Streamline Innovations offers a particularly robust chelated iron catalyst, known as TALON®. TALON chemistry is the keystone of the TALON Sulfide Elimination System, which helps reduce odor issues in industrial and municipal wastewater streams across the United States. www.streamlineinnovations.com
Contact
Contact Streamline Innovations to learn more about next generation Redox solutions for odor control and determine if the TALON Sulfide Elimination System is right for your wastewater facility.
Stewart North
Business Development Director, Municipal & Industrial
E: Stewart.North@streamlineinnovations.com
T: (859) 948-1638
About Streamline Innovations
Streamline Innovation’s vision is Eliminating Emissions Through Technology. We help heavy industry around the world achieve environmental performance objectives, improve sustainability, and transition to a sustainable, low-carbon economy.
Streamline’s environmentally forward H2S treating solutions help achieve the “E” in ESG. H2S is present in many industrial processes throughout the world. Our technology can be applied across industries, delivering a sustainable solution that eliminates H2S, a leading cause of human inhalation accidents and source of SO2 emissions, a primary cause of acid rain. TALON chemistry treats effectively in both gas and water phases.
Streamline believes that achieving environmental sustainability directives requires data. Creating intelligent systems that operate effectively and efficiently without human intervention is critical to measuring and reducing emissions that harm the environment. We integrate advanced process control, data collection and analytics in our technologies to provide a total solution for customers.
We serve organizations in multiple sectors, including Energy/Oil & Gas, Biogas, Landfill Gas & Renewable Fuels, Municipal Wastewater and Industrial Air & Water.