Citric Acid Passivation System

Passivating LineThis citric acid passivation system was designed, fabricated, and installed by PKG Equipment for passivating beer kegs. The system included a tank line of thirteen stations, approximately 1300 gallons each, including a stainless steel dryer. In-line process tanks were fabricated from copolymer polypropylene, carbon steel, or 304 stainless steel. Tanks included accessories such as heaters, pumps, filters, educator agitation, and drip shields. The tank line was modularized on the shop floor with steam piping, water feeds, drain piping, push air, and sparge air, then tested, and disassembled into modules for shipment.

Stainless steel process racks, designed and fabricated by PKG, provide venting and draining of kegs through one hole when traveling from station to station. These racks are transported through the line via an automated hoist. The hoist has three modes of operation; manual, semi-automatic, and automatic, and a capacity of 2000 pounds. The automated system includes a control panel with programmable controller and touch screen operator interface. A data collection system was provided to aid in troubleshooting and for recording temperatures, level control, immersion times, and other process parameters.

The ventilation system consisted of PVC hoods, ductwork with blast gates for control and balancing of the system, a 33,000 cfm exhaust fan, and push air on all vented tanks. Hoods were mounted along the back of the tank line. A make-up air heating unit was also provided to balance the air in the building.

An automatic wastewater treatment system included a sump tank with pump, 1500 gallon surge tank, 1500 gallon storage tank, two stage reactor tank with pH analyzers, chemical feed pumps, mixers, and a final discharge tank with pump and pH analyzer to check final pH levels. Holding tanks of molded XLPE were also provided for nitric acid and alkaline cleaner/citric acid.

The containment area, coated with Hi-Chem Rhino Lining, encompassed the tank line and wastewater treatment system.

Start-up assistance was provided with the turnkey installation.

Highlights of this Citric Acid Passivation System

Project Description

PKG Equipment Inc. designed, fabricated, and installed a citric acid passivation system.

Product Name

Citric Acid Passivation System


93′ long x 20′ wide

Materials Used

Process Tanks:

  • Copolymer polypropylene
  • Carbon steel or 304 stainless steel

Wastewater Treatment Tanks:

  • XLPE or copolymer polypropylene


  • PVC hoods, ductwork, exhaust fan, and radial fan

Containment Area:

  • Coated with Hi-Chem Rhino Lining


  • Free standing crane superstructure
  • 13 stations – approx. 1300 gallons each, including a stainless steel dryer
  • Heaters, pumps, filters, educator agitation, and drip shields
  • Modularized with steam piping, water feeds, and drain piping
  • 33,000 cfm exhaust fan
  • Push air on vented tanks


  • One automatic, programmable, hoist with manual override
  • Capacity of 2000 lbs.
  • Data collection system


  • Wastewater treatment system
  • Make-up air heating unit
  • Turnkey installation
  • Start-up assistance
Industry for Use

Beer Keg Manufacturing