F&A Dairy, Wisconsin

Project Background & Challenges

F&A Dairy had outgrown its wastewater treatment facility by April 2009. Thanks to significant increases in production, the plant was now processing close to 1 million pounds of milk per day. Having opened the facility’s doors in 1974, the 35-year old system was designed to handle 3,000 ppd of BOD, but was now unable to keep up with the plant’s needs. The original static-tube aeration system was at capacity with all four 50-Hp blowers (3,000 cfm each.) Even at capacity, the system was only able to maintain a dissolved oxygen level of 0.1mg/L which resulted in operational troubles and odors.

For a short-term fix while F&A Dairy searched for a solution, the plant purchased an Ultra V 30 Hp aspirating pump and rented two more powered by a portable diesel generator. This added a 90 Hp load onto the electricity consumption in addition to the four 50Hp blowers powered by a portable diesel generator to handle peak summer conditions.

“[The plant has] been able to spray irrigate their effluent because their nitrogen concentrations are lower than they have been in the past. That has saved the plant money because they are no longer paying the city to treat their effluent.”

Jonathan Butt, Symbiont

The EDI Answer

For a permanent, long-term solution, F&A Dairy hired Symbiont, a prominent consulting firm located in Milwaukee, WI. Symbiont studied the plant wastewater and its existing treatment processes as well as viable aeration system technologies. They evaluated F&A Dairy’s other plant in Las Cruces, NM, which already employed EDI’s Floating Lateral System. Upon the completed evaluation the recommendation was provided to install EDI’s system which could be installed without dewatering the existing treatment lagoons, and would provide an energy efficient system to meet the demands of the 1 million lbs/day production.

F&A purchased a FlexAir fine-bubble aeration system from EDI that uses floating HDPE air lateral assemblies with suspended-tubular, fine-bubble, flexible-membrane diffuser assemblies. The system was installed in the summer of 2010 with great success. The upgrade reduced power consumption, handles peak loads, maintains dissolved oxygen and provides operating flexibility.

System Drawing: F&A Dairy; Floating Lateral System

System Highlights:

• High-density polyethylene pipe for maximum durability
• Diffuser assemblies are retrievable without taking basin off-line for maximum process reliability
• Heavy wall piping and all-welded construction including in-line and branch transitions for maximum mechanical integrity
• Designed to withstand significant external forces from wind, heat, ice and varying water level conditions

Upgraded System Performance