Definition - What does Acid Attack mean?
Acid attack can be defined as the process of hydrogen sulfide gas converting to sulfuric acid by biological activity in the presence of moisture and causing corrosion in pipes. Bacteria that live above the waterline convert the released hydrogen sulfide gas to sulfuric acid, which drips back down into the wastewater and is neutralized into sulfate, allowing the reaction to begin all over again.
Pipes affected by this problem can be rehabilitated using trenchless rehabilitation methods such as cured-in-place pipe (CIPP), sliplining, and mechanical spot repair.
Trenchlesspedia explains Acid Attack
Acid attack due to hydrogen sulfide takes place when conditions in the sewer are ideal for it to react with its surroundings. Some conditions include low flow velocity, excessive detention time due to an inadequate slope, and the presence of dissolved sulfide. Though hydrogen sulfide corrosion is one of the major causes of pipe damage and failure, it is not something that cannot be treated or controlled.
The first step to controlling corrosion is to carry out periodic condition assessment, and ensuring that all pipelines are thoroughly inspected for signs of corrosion damage.
The best way to prevent corrosion is to use pipe and fitting material such as polyvinyl chloride (PVC), high-density polyethylene (HDPE) and fiberglass reinforced plastic (FRP). These materials are chemically neutral when exposed to sulfuric acid.