Industrial Wastewater Treatment
EPIC Systems reduced effluent costs for a major consumer products company by designing and installing a complete industrial wastewater treatment system including a DAF and flocculation unit.
CLIENT: A Fortune 500 company
INDUSTRY: Consumer Products
KEY ENGINEERING FEATURES:
- Project scope: complete project engineering & design efforts, site civil upgrades, pipe racks and bridges, equipment/instrumentation/specialty procurement, pipe spools, process equipment and raw material pumping systems
- Manage contractor install, controls/programming, start-up / validation
- Complete industrial wastewater treatment and waste transfer systems, including Dissolved Air Flotation (DAF) tank, and flocculator
- Caustic chemical treatment of wastewater
- Pre-fabricated building installation with HVAC system for cooling
- Heat trace system for flocculator to prevent pipe blockage
- Fats, oils and solids removal from wastewater before going to municipality
- Forcing fats, oils and solids suspended in wastewater to top for removal
- Installation of new building to house treatment system
- Intersecting pipe bridge strut removal
- Flexible waste transfer system
- Fat buildup in flocculator requiring heat trace system
- Budget constraints
AN EPIC SOLUTION
A consumer products company had a process requiring the removal of fats to a municipality wastewater treatment center. The runoff had a high concentration of suspended fats, oils and solids. Recent changes to local government environmental laws created a need for cleaner wastewater treatment to the facility.
The company had been paying a fee, but the municipality stricter guidelines would reject wastewater from the facility if the fat content was not drastically reduced. EPIC proposed the following wastewater treatment solution, working with a client-selected equipment company:
EPIC’s Proven Solution
EPIC managed the entire project from the design stage through the final startup. A pre-existing unusable structure was cleared from the job site. The pipe rack running above the building space was reinforced along the top, and the ground struts were removed to make room for a new wastewater building.
EPIC managed a sub-contractor who completed the site civil work and installed the new 2400 ft2 pre-fabricated building. EPIC worked with the building fabricator to design the building arrangement. Using a pre-fabricated building lowered costs compared to a traditional stick-built solution. A complete HVAC system was installed to cool the MCC controls room.
EPIC installed an Allen Bradley PLC and integrated the flocculation system and DAF into the waste stream. The system was designed for water traveling through the flocculator to be chemically treated with a caustic solution. Fats and solids in the wastewater are combined and rise to the top of the solution. EPIC installed a small caustic tank in the wastewater treatment building with an automatic fill on demand feature from a larger pre-existing caustic tank, located inside the production facility.
A heat trace system was added to the flocculation piping to raise the temperature of the wastewater. The high percentage of fats in the waste stream was prone to build up and caused blockage if allowed to transform to a solid state. The heat trace system was purposely designed to keep fats in a liquid state during flocculation, the only part of the treatment process with relatively narrow piping.
The flocculation system was seamlessly joined to the Dissolved Air Flotation (DAF) tank. A portion of wastewater must be removed from the stream and injected with high pressure air. The excess was engineered to enter the DAF based on resonance time to create turbulent upward flow. The high pressure air/water solution force the flocculated fats and solids upward at a high rate. Steady upward pressure exists throughout the DAF to keep fats and solids at the top of the tank.
A belt skimmer was installed to scrape fats from the top of the tank into a hopper bin. A trigger inside the trough is designed to run a sludge pump when the trough is filled. The pump siphons sludge into storage tanks.
The trigger system with batch pumping proved to be a less expensive waste removal method than continuous pumping operations. EPIC specified hookups on the outside of the sludge tanks so that sludge could be easily pumped into trucks and removed periodically.
A second filtration step was also installed. Wastewater passes through this process before being released to the municipality. After the DAF system was installed the municipality was able to accept effluent from the plant and without extra fees.
- Resolved issues with municipality and eliminated effluent disposal fees
- Reduced project costs through use of pre-fabricated building, batch pumping system and on-demand caustic system