Biological treatments for H2S removal
The compound H2S —hydrogen sulfide— smells like rotten eggs and is produced as a result of many industrial facilities’ processes, including in the brewing, food and beverage, pulp and paper, pharmaceutical and oil & gas industries.
Problems caused by the hazardous compound range from stinking up neighborhoods to corroding industrial equipment to putting public and environmental health at risk, so its removal has become a necessary component of industrial processes worldwide.
Biological H2S removal systems
Biological odor control systems eliminate H2S using bacteria and other microorganisms that break down stinky compounds. Other odors treated in this fashion include inorganic odors such as ammonia, organic odors and volatile organic compounds (VOCs).
It works like this: Air contaminated with H2S is collected and forced through a vessel filled with media that harbors the growth of microorganisms. Water added to the vessel maintains that growth and is critical to the biological breakdown of H2S. The microorganisms use the offending compounds as a food source, essentially eating the odors out of the air. The result is clean air (which is released from the vessel and disperses into the environment) and odorless water that’s safely drained away.
Biological systems include:
- Bioscrubbers – These systems force air upward through a vessel filled with synthetic media. Water containing microorganisms is recirculated through the system. During this process, the microorganisms in the water feed off of the H2S, and clean air is released.
- Biotrickling filters – These filters feature microorganisms that grow within structured media inside the vessel. Irrigation water passes through the vessel to rinse away the metabolized H2S as the air travels upward. Biotrickling filters do not recirculate water. Learn more about the subtle but critical difference between these systems here.
Biological systems present a cleaner —and often cheaper and more efficient— alternative to non-biological H2S treatments.
Non-biological H2S treatments include:
- Adsorbent filter systems, like activated carbon filters, which trap sulfur compounds in the filter and emit air free of odorous compounds. But these systems require regular replacement of the adsorbent media, which adds to its overall cost.
- Chemical H2S treatment systems which use various chemical solutions that bind to sulfur and remove it from the air. These chemicals are costly, and they’re also dangerous.
Nuisance odors vs. pollutants
Biological H2S removal systems are designed based on the volume of impacted air emitted from an industrial facility and the concentration of offending or hazardous compounds in that air. Factors affecting the design include the facility’s proximity to other industrial, commercial or residential developments, the resources and infrastructure at hand at the site and any applicable environmental rules regulating emissions.
For example, breweries, dairies or food processing plants emit H2S and other offending odors, but usually not at dangerous levels regulated by federal and state environmental statutes. Air treatment solutions are designed in these cases to remove offending odors to ensure those facilities maintain favorable working conditions and remain good neighbors to those around them.
On the other hand, some pharmaceutical and oil & gas facilities emit air far more concentrated with H2S and other offending compounds. Air with high concentrations of H2S is harmful to environment and to those exposed to it. In fact, it’s odorless at high concentrations. Without sensitive equipment, one would be unable to detect it before it was too late.
It’s also important to note that H2S at any concentration can pose corrosion risks to industrial equipment.
Biological hydrogen sulfide treatment systems are necessarily designed based on what a facility needs to achieve—whether that’s to keep the neighbors happy, to keep workers safe and equipment in good working order, or to comply with environmental rules.
BioAir Complete™ from BioAir Solutions
BioAir Complete™ is a unique service that BioAir provides whereby we take ownership of a facility’s entire odor or emission problem. This turnkey service starts with an on-site evaluation of your facility’s processes. Our process experts examine the mechanics of your facility and identify sources and concentrations of odors that need to be removed.
Then, based on that information, we design and build an H2S removal system from scratch to suit your facility’s needs. After that, we start up the system and train your team on its operation and maintenance. We’re also on-call for any service or support needs that may arise, with technicians in place to serve all of our installations throughout the U.S. and globally.