60 MASTER BREWERS ASSOCIATION OF THE AMERICAS MBAA Annual Conference October 13 – 15, 2011 Hilton Minneapolis Minneapolis, MN Reducing Carbon Dioxide (C02) Usage Through the use of Acid and Detergent Cleaning of Bright Tanks Dana Johnson/ BIRKO Corporation Presentation Abstract Greenhouse gas emissions (i.e. carbon dioxide, CO2) from the brewery can be decreased by cleaning bright tanks with acid and detergent rather than with caustic. When cleaning bright tanks with acid and detergent only, the bright tank can remain under pressure and the cleaning can, in most cases, be done with ambient temperature water. In addition to being a sustainable practice, this method also has the added benefit of reducing the amount of dissolved oxygen (DO) in the subsequent packaged beer because the tanks do not need to be purged of carbon dioxide, cleaned, cooled and re-carbonated as they do when cleaning-in-place (CIP) with caustic. Acid also recycles well, thereby reducing chemical usage at the same time. By incorporating a detergent additive blend along with the acid, protein dispersion and beerstone (calcium oxalate, Ca2CO4) displacement is enhanced as well. Introduction Why Clean Bright Tanks With Acid? 1.Cleaning bright tanks with caustic (NaOH and/or KOH) presents several issues that can create efficiency problems and increase dissolved oxygen levels subsequent finished beer processed through the tank. 2.Carbon dioxide has to be removed from the tank to keep it from neutralizing the caustic and more importantly, not implode the tank from the vacuum created when the carbon dioxide inside the tank is drawn into the caustic solution too quickly. 3.For caustic solutions to be effective, the tank typically needs to be cleaned warm, which increases the demand for hot water. Once cleaned and sanitized, the tank needs to be re-cooled and then re- carbonated before it can be filled with beer again. 4.In addition to taking a lot of C02, re-carbonating the tank takes time and a small amount of oxygen remains in the tank, so the subsequent beer put through the tank can have a higher level of DO. Acid Active Ingredients:  Nitric Acid, (HN03) an oxidizing acid known to be aggressive on organic material and for passivating stainless steel.  Phosphoric Acid, (H3PO4), a mineral acid used for decades in the brewing industry to neutralize caustic solutions and remove hard water scale. It is generally not effective on beerstone by itself.  Stablizer (Proprietary, assists in promoting the concentrated acid shelf-life.) Acid and Detergent Additive Chemical Properties Detergent Additive Should Provide the Following Properties:  Water Conditioning  Metal Ion Chelation  Wetting  Penetration  Protein Dispersing  Foam Suppressing  Rinsing Typical Usage Requirements BIRKO Ultra Niter (nitric/phosphoric acid blend) Suggested Concentration: 1 -2 (one-to-two) fluid ounces (30-60 ml.) per gallon (4 liters) of ambient temperature water. (1: 1,892-3,785 as supplied). Point of Application: Typically either with a CIP Tank or added at the point of use. BIRKO X-Puma (liquid detergent additive): 1 (one) fluid ounce (30 ml.) per 64 oz. (1,920 ml.) of Ultra Niter concentrate used. Point of Application: Typically added at the point of use. The use of acid and detergent only cleaning of the bright tank can significantly reduce the amount of C02 needed in the brewery. Benefits include: Decreased Dissolved Oxygen (DO) in the subsequent beer processed through the bright tank. CIP cycle time reduced (easier bright tank cleaning). Increase in shelf life of packaged beer due to significantly lower DO levels in the beer. Reduced time, labor, and chemical usage. As the craft brewing industry grows and requires larger and larger bright tanks, moving away from cleaning the bright tank with caustic for each and every cleaning becomes more important to save time, chemical, energy, and CO2. Acid cleaning of bright tanks under pressure can significantly reduce the amount of CO2 needed to replenish the bright tank and significantly reduce DO levels in the subsequent beer run through the tank. Lower DO level in the finished beer along with reduced energy, C02 usage is much better for the breweries bottom line as well as reducing the “carbon footprint” as well. Benefits Conclusion Acid and Detergent Bright Tank Cleaning Procedure Typical Subsequent Beer DO Level (ppb) in Caustic vs. Acid/Detergent Cleaned Bright Tanks 1.Rinse 2.CIP 3.Rinse 4.Sanitize