New line looks golden for WeserGold
The Elopak machine uses vaporized hydrogen peroxide or “dry” sterilization minimizing the need for water compared to the two rotary aseptic machines. WeserGold’s plant has a sterile water unit that is used only to cool down the machine after sterilization. No additional aseptic water is needed to sterilize the bottles.
“We had already tested systems that sterilized bottles with water but it was our decision to use this method of sterilization and we selected the Elofill machine” Driessen says. “It reduces the costs of water consumption and wastewater treatment so it gives us an economic advantage. Limiting our water consumption also fits into our concern for the environment.”
External bottle sterilization
PET bottle varieties that will be filled on the new aseptic line will be molded by WeserGold at Rinteln. The company purchases preforms from a local supplier then stretch blow-molds them into bottles on a SBO-10 machine from Sidel. The machine was purchased specifically to supply the new aseptic line.
Bottles are air-conveyed by their 38-mm necks from a lower level in the plant some 300 meters to the infeed of the Elofill 6000.
Grippers carry bottles by their necks throughout the aseptic filling process. “As long as we use that same neck size and thread we can run different bottle sizes and shapes through the equipment without changes” notes Driessen.
According to Elopak the outfeed conveyor can be raised to accommodate different bottle heights. These settings are programmed into the various bottle “recipes.”
Constant back pressure on an infeed starwheel synchronized with the overall infeed system ensures accurate infeed of bottles as they enter single-file into the external bottle sterilization section. Vaporized hydrogen peroxide is applied as a mist to treat the outside of bottles. The H2O2 cannot be seen as the bottles are conveyed through this section. No sterile water rinse is necessary following external bottle sterilization.
Each set of 10 bottles is transferred by grippers from the sterilization area to 10 neck grippers that hold them in place on a transport beam positioned in the lower part of the machine. Several of these beams are spaced evenly on four sectional belts carried on an oval-shaped track from upper and lower areas in the aseptic area.
There are two air zones inside the machine both of which are treated with Class 100 air. One zone is the aseptic chamber which is treated with three times more HEPA-filtered air than the second zone that encompasses the bottle infeed and outfeed section and the internal bottle transport system. That’s done to minimize the potential for contamination in the aseptic chamber.
A pneumatic device raises the transport beam about 1.5 meters to the aseptic chamber. There the 10 bottles are held by grippers and transferred left to right through internal sterilization filling and capping stations.
Heart of the system
The first station is internal sterilization. Nozzles dose each of the 10 bottles with H2O2 at 78ºC. “It’s the maximum temperature a normal PET bottle can stand before it starts to shrink” says Georg Zuzok general manager of filling equipment for EPS. Hot air is used to drive out any residual H2O2.
At the heart of the aseptic machine are 10 electronic volumetric fill heads. Above the machine juice is pumped through an aseptic system of stainless-steel pipes valves and pumps. High-temperature processing sterilizes the product. It is pumped through a manifold that distributes the liquid above the 10 filling nozzles. Each nozzle includes a separate modulating valve or induction flow meter so the fill level can be carefully controlled as are other machine functions by a Siemens S7 PLC.
After filling liquid nitrogen is used to reduce oxygen in the headspace prior to cap application. The nitrogen also helps provide bottle rigidity after capping according to Elopak.
The next step is closing the bottle. Injection-molded polypropylene caps from different suppliers incorporate a foil-based liner. A cap conveying system from H.F. Meyer equipped with Intralox plastic belting feeds caps to a mezzanine level. They’re treated with vaporized H2O2 before they’re torqued onto the 10 bottles. Induction sealing is then used to adhere the liner in the cap to the mouth of the bottle. No retorquing is required. This entire process repeats with every 10 bottles as they transfer from the sterilization section to the aseptic filling area.
Investment challenges
How does the company justify the purchase of the new line not to mention the new molding machine? “Nowadays you cannot really calculate a return on investment on such projects because we work on a seven-year depreciation schedule” says Driessen.
But he says “if you don’t do it [invest in equipment that produces bottles desired by consumers] you will not be in the market any more because the European consumer is so focused on new product and new bottle shapes.”
It’s premature to determine savings from reduced water consumption and treatment for the new aseptic line as compared to the two rotary aseptic systems but Driessen does anticipate they will help the bottom line. Further ROI on the equipment could come if the company changes its glass bottles to PET something Driessen expects. Ultimately satisfying ever-changing consumer demand justifies WeserGold’s investment.

























































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