Problem: Massive Hydrogen Sulfide Attack
Solution: Direct-To-Aggregate Liner
PHOTOS: After 4 Years Exposure
TOP: No damage even in extreme hydrogen sulfide gas conditions (Rust stains originate from the cast iron ring.)
BOTTOM: Biofilm, the dark color, is observable toward the bottom. The epoxy surface is undamaged.
HISTORY: A series of manholes were discovered suffering from massive hydrogensulfide attack. The concrete structures had been in service only about five years. The lines passing through the manholes came from a series of lift stations, some of which pumped only once or twice a week. The local environment of Amarillo, TX is generally arid and hot. When the lift stations' are pumping large quantities of hydrogen sulfide gas are created. Microbes utilize the sulfide gas as an energy source and , through a series of complex chemical reactions, create sulfuric acid which attacks the infrastructure. Microbial induced corrosion (MIC) is widespread throughout wastewater systems.
CLEANING: Water blasting at 3500psi removed two inches of deteriorated concrete leaving a rough surface perfect for epoxy bonding.
LINING: The Direct-To-Aggregate lining method was chosen that eliminates adding corrosible cement.
250 mils of PureEpoxy NPR-5303 epoxy was sprayed directly onto the rough surface, filling the interstitical voids and encapsulating aggregate. The manhole surface is massively protective, and structurally enhanced.
RESULTS: No corrosion, blistering or cracking has occured, or can occur. Manhole structure will provide decades of additional service.