SweetRipe Drinks Ltd., a privately owned Canadian beverage company with the largest Tetra Pak facility in Canada, produces 20 million cases of fruit beverages annually which it distributes throughout Canada, the USA, Europe and the Middle East.
The company has three state-of-the-art plants (two located in Missisauga, Ontario and the third in Port Williams, Nova Scotia) which produce Tetra, Glass, PET and Gable-top (refrigerated).
The glass bottle
rinsing facility utilises a heat-exchanger to heat up the recirculating water which is sprayed on to the outside of the bottles to prevent thermal shock when the bottles
are filled with hot pasteurised juice which can reach 95°C.
A build up of scale on the plates of the heat exchanger resulted in the loss of heat transfer coefficient and necessitated the shutting down of the unit to clean the plates.
Without constant cleaning, the standard required temperature of the circulating water could not be achieved, and increased the probability of thermal shock at the filler.
The cleaning of the plate heat exchanger had taken two mechanics up to three hours every two to three weeks. The plates had been difficult to separate and, once apart, the scale had to be chiselled off and the plates soaked in an acid bath.
In addition, the scale was acting like abrasive sandpaper and causing wear on the EMT wear strips on which the rubber bottle
grip holders run.
was installed on to the 45 foot, 2 inch brass water outlet pipe feeding the Alfa Laval plate heat exchanger.
The System was treating a water flow rate of between 35 and 40 gpm with an upstream temperature of 180 °F and pressure of 20 psi and a downstream temperature of 125°F and pressure of 30 psi.
During a planned shutdown, just 1½ weeks after installation, the circulating pump was pulled out and the inside of the volute and impeller were examined for scale build up (normally, excessive scale resulted in SweetRipe replacing the pump every 18 months). Much to their surprise, the inspection team found the pump to be relatively clean of scale and the small amount of scale present was soft and easily removed with a brush. It was also found that the pump and inlet pipe were totally free of any scale build-up.
When the heat exchanger plates were pulled apart, so that the gasket could be replaced, it was noted that 100% more of the previous existing scale build-up had been dissolved and passed through the system to drain.
A further inspection showed the plates to be completely scale free and were in fact cleaner than the steam side of the heat exchanger.
Commenting on the technology application, Kenneth Macauley, Vice President Operations said: "The System performed remarkably well. Downtime has been saved in line stoppages and time spent cleaning the heat exchanger. Even the inside of the rinser is free of scale. As the heat exchanger is now operating efficiently, our steam demands on this unit have dropped from 110 psi down to 12 psi."