Ice pigging reduces changeover waste

A novel hygienic ice pigging machine, expected to provide users with big savings on raw materials wasted during changeovers between piped products, has been launched for use in the food processing sector.

The technology from Suez Advanced Solutions (formerly Aqualogy Environment), the AQL500, clears pipes using slush ice instead of water, a common method of purging product from pipes in food processing. Suez expected to deliver its first unit either in the UK or US “within the next couple of months”.

Slush ice has unique rheological properties that means it can pass through variations in pipework such as valves, bends and changes in diameter without becoming stuck in the pipe, yet has highly effective cleaning properties similar to a solid pig when in the pipe.

‘Step change’

For the food and beverage sector, ice pigging is said to bring a “step change” in the level of production efficiency. “It is highly effective at removing soft things, such as ketchup,” said Matthew Stephenson, Suez's head of ice pigging.

Last year, the technology was trialled on the Surprise production line at the Newton Abbot site of organic yogurt maker Yeo Valley, where it saved around £350,000 in product recovery.

“Ice pigging provides significant improvements for pipe cleaning, with up to 90% recovery of product,” said Suez ice pigging process engineer Tim Deans.

Today, during product changeover, large quantities of water may have to be used to clear pipes of product, resulting in wastage of high-value product, and at the same time creating large amounts of effluent to treat. Ice pigging can help the recovery of the majority of product left in a pipeline, and in doing so improve the production efficiency of the plant, reduce water consumption and reduce effluent produced.

Five years of development

The launch of the AQL500 factory-ready hygienic ice pigging machine comes as a result of five years of development, following the technology’s invention by Professor Joe Quarini at the University of Bristol. The machine is designed for permanent installation into a facility where it will provide 'ice pigs' on an automated basis.

“Much of the development of the machine has been concerned with adapting the technology to be suitable for the stringent hygiene requirements that food producers expect,” said Stephenson.

“From top to bottom, the AQL500 uses food-grade components and is fully cleanable itself. The ice produced by one of our machines should be the cleanest ice anywhere in the world.”