Marinette, Wisconsin, needed to adjust how it disposed of its wastewater biosolids due to changed regulatory conditions regarding perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). Requiring an alternative to land applying its liquid anaerobically digested biosolids, we assisted Marinette’s wastewater treatment facility (WWTF) with pilot testing biosolids dewatering and drying (D&D) equipment that would allow the WWTF to landfill dispose of its dried biosolids. Based on the pilot test results and our engineering report, Marinette purchased the biosolids processing equipment directly from vendors to expedite the construction schedule, and we prepared plans and specifications for the installation of the equipment and construction of a new cake storage building. The D&D equipment was installed in an existing building. During construction, we also assisted Marinette with the review of shop drawings and construction coordination.
Components of the new biosolids processing system included a biosolids grinder, sludge pumping, dewatering screw press, polymer feed system and mixing, Shincci brand belt dryer, dried solids conveyance, and dried material storage building.
The modifications to the biosolids D&D equipment allow Marinette to stay in compliance with wastewater biosolids disposal regulations using the new drying technology (Shincci) to produce 85 to 90% dry solids for disposal.
