A wastewater treatment plant (WWTP) had a severe buildup of vivianite throughout 175 feet of 4” diameter piping. Often in wastewater treatment, vivianite and struvite are menacing deposits which form and drastically reduce flow. The deposits are likely to be present in turbulent areas such as elbows and bend in the line. Both vivianite and struvite can completely restrict flow if not periodically removed from equipment and piping.


A 90-degree pipe section containing a substantial amount of vivianite deposit (>1” thick) was provided to Apex Engineering Products for testing and evaluation. Through laboratory tests, it was determined that a concentration of 100% RYDLYME was required to effectively dissolve this particular vivianite deposit. The facility proceeded with a full system cleaning as outlined below. Scale deposits may not accumulate uniformly throughout a system. Every site’s scale composition will vary. Please contact Apex for assistance in providing a safe chemical solution.


CHALLENGE: Vivianite had restricted flow in the system’s 4’’ by 175’ pipe.
SOLUTION: Circulation of RYDLYME at 100% concentration for 13 hours through a 4’’ 90° pipe.
RESULTS: After 13 hours of RYDLYME circulation, the vivianite was dissolved and the flow rate had tripled!