Concrete Corrosion. Mention corrosion and most people think rusting metal. True, but reinforced concrete also corrodes and deteriorates. How so?
Reinforced concrete is the backbone of every wastewater collection system. Alkaline materials in the cement phase of concrete are extremely susceptible to corrosion.
Hydrogen sulfide (H2S) is the root contributor to corrosion in sewer systems. H2S is a byproduct of the microbial breakdown of organic matter in the absence of oxygen gas, such as in swamps and sewers; a process commonly known as anaerobic digestion.
In a sewer system, H2S forms sulfuric acid at the crowns of pipes. The sulfuric acid can weaken and soften concrete which leads to a loss of structural integrity and increased intrusion and infiltration. (H2S is also very poisonous, but that’s another story.)
So, every system has corrosion problems. How do you know how bad your problem is?
At BioConversion Technology, we measure corrosion rates of different metals and materials commonly found in water and wastewater treatment systems. Gas meters are used to measure atmospheric H2S levels and waste streams are monitored for pH and dissolved sulfide levels to track sulfuric acid generation. Additionally, we install corrosion coupons composed of dissimilar metals to track the rate of corrosion at targeted locations.
Corrosion of your water and wastewater infrastructure often goes unnoticed because it is out of sight. Pipe survey crews can use special cameras to video sewer conditions that cannot be normally be seen.
Finally — if you have not already done lab analysis or video inspection – your neighbors will tell you. H2S smells like rotten eggs. It is especially severe around lift stations and sewer mains. Your phones will be ringing with complaints from the community.
What to do?
The best preventive maintenance program is to tackle the source. Septic environments are the breeding ground for H2S. Use of chemical and biological agents to shift the environment from septic to anoxic conditions can prevent the formation of most corrosive and malodorous compounds.
BioConversion Technology specializes in bio-augmentation solutions. Biological agents thrive in oxygenized environments where excess sulfur based materials are consumed naturally without the formation of corrosive compounds.
This isn’t a “one size fits all” solution. We tailor dosing and process control adjustments to your specific situation based on metrics we measure in your system. Immediate benefits are reduced odor and corrosion. Long term reductions in downtime, rehabilitation and replacement costs also result from a comprehensive odor control and corrosion reduction program.
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