Ultra-Light, Recyclable One-Way PET Keg

An alternative to traditional steel beer kegs said to address two disadvantages—safety and cost—has been developed by Cyprus’ CYPET Technologies. Called the Zeg, this is an ultra-light, 100% recyclable one-way PET keg, which has been built using CYPET’s patented injection stretch blow molding process that reportedly has been proven to be able to produce some of the industry’s most innovative and stunning PET containers.

The patent-pending Zeg features a top chime and handles that are integrated with the rest of the keg body. Having the top chime, handles and keg body formed as one piece is said to significantly reduce the keg’s production cost, as it eliminates fabrication of a separate top chime and its subsequent assembly into the keg. Moreover, the strong mechanical properties of PET allow for the top chime to be lighter in weight than conventional chimes yet still be able to handle the loads that the Zeg will face through its life cycle.

On the safety side, apart from having a reportedly high burst pressure—four times higher than the normal beer dispensing pressure—the Zeg features a patent-pending pressure relief valve that is incorporated on the neck of the keg. In case of internal pressure build-up, the valve will  be triggered automatically to release the excess pressure. The valve is said to protect the Zeg through its life cycle, even while it is coupled to a dispensing system. Once the Zeg is empty, it can be easily depressurized manually using no tools, making it ready for recycling.

Delivering efficiency from the brewery, to distribution, to the tap room, the ZEG is said to be the perfect alternative to its steel counterparts, thanks to no cleaning, return or theft costs. Coming to the brewery pre-purged with Nitrogen, it is said to be pristinely clean with excellent O², CO² and UV barrier properties, which keep the beer fresh and intact with a year-long shelf life.

According to CYPET development engineer Michalis Sideris, the Zeg was developed primarily for the North American market. “It’s a 1/6^th barrel keg—meaning it has a volume of 5.2 gallons. It’s compatible with the American industry standard keg collar, sanitary cap and dispensing D valve, and was designed to meet the American Brewers Association guidelines for one-way beer kegs.”

However, Sideris notes that by changing its D valve to the appropriate type, the Zeg can be used in other markets such as Europe, South America, Russia and China. Meanwhile, the unit’s metallic color is derived from a silver color masterbatch that is added to the PET formulation. The masterbatch is approved for use with the special PET resin that is needed to give the kegs a high oxygen and carbon dioxide barrier, he explains.