Water is the most important raw material for the beverage industry. However, in many places water resources are under increasing pressure from global warming and pollution. And so, beverage makers are seeking ways to use this “blue gold” more efficiently.
Norbert Ottmann, from Krones’ sustainability consulting service, said, “Our most ambitious customers in the CSD arena are setting consumption targets of 1.3 or even 1.1 litres of water per litre of beverage produced. And that number includes the litre or so of water that goes into the drink itself, meaning the remaining water budget for the line is calculated with very narrow margins.”
At present, the average water consumption in most beverage plants is still above these “best in class” targets. While it’s true that water supply has been a major consideration in some regions since time immemorial, most companies have, until recently, focused primarily on energy consumption.
But that is changing now. In its latest benchmarking study, the Beverage Industry Environmental Roundtable – a coalition of 17 global beverage companies with more than 1600 plants worldwide – reported its members were increasingly turning their attention to efficient and sustainable water use.
Water consumption facts and figures
- The Association of German Mineral Water Producers: 1.5 to two litres per litre of product on average
- Average water consumption according to the Beverage Industry Environmental Roundtable:
- all beverages (beer, wine, spirits, CSDs): 2.4 litres per litre of product;
- bottling-only facilities: 1.93 litres per litre of product;
- carbonated soft drink facilities: 1.91 litres per litre of product; and
- breweries producing beer only: 3.08 litres per litre of product.
Where can we make adjustments?
The question then arises – how can we reduce water consumption in beverage production?
Because an especially high volume of fresh water goes into the processes of flushing, rinsing and cooling, there are several points where potential savings can be made.
Beverage makers may be able to flush or rinse less, reuse the rinse/flush water, recover heating and cooling energy and use it elsewhere, or recycle process water in a cooling cycle instead of simply running it down the drain.
Each company has to weigh these options individually to determine which ones are feasible and make economic sense in their operations. And Krones’ sustainability experts can help with that decision-making. Applying their knowledge of the machines and how they work together, Krones’ sustainability specialists analyse water flows along the line or in the entire factory to identify possible places where savings can be achieved. They work with the customer to then develop specific solutions to permanently reduce consumption.
Water savings can be accomplished right out of the gate, in the production planning stage – because the longer each individual production cycle runs, the less frequently pipes need to be cleaned for a product change.
The flushing procedures themselves are another excellent point for fine tuning. In essence, the objective here is to prevent any carry-over of aromas or allergens from one product to the next.
Katja Enzmann is responsible for thermal processes and sustainability in process technology at Krones. “There is always room for improvement when it comes to flushing the system,” Enzmann said. “We draw on our knowledge and experience to deliver actionable advice. Ultimately, the customer will determine how much flushing water is necessary to accomplish the level of assurance they need to prevent allergen or flavour migration.”
Ottmann added, “Looking at the entire line reveals even more potential for water savings. In theory, you can optimise each part of the line individually. But when you bring together several different stand-alone modules, they complement each other. The resulting synergies make the whole far greater than the sum of its parts.
“Usually, that means capturing heat or cooling energy at one point and using it somewhere else in the line. This, in turn, can also yield water savings, as described above. These concepts are typically tailormade and developed in consultation with the customer.”
Synergies that save water
Warmer filling in the brewery: Thermal energy from the bottle washer is used to pre-warm the beer. Less water is needed to cool the bottles at the bottle washer discharge. In addition, warmer filling temperatures mean less condensation forms on the filled containers.
A brewery project in a very warm region uses the cold beer as a cooling medium. The result is a series of synergies that save water, for example in the bottle washer.
Cold filling CSDs: Because condensation forms on the filled bottles (which are a cold eight to 10C), the bottles must be warmed prior to labelling. Krones’ EquiTherm Coldfill can help with this. A heat pump captures the cooling energy from the mixer and brings it up to a higher temperature for use in the bottle warmer. Besides yielding considerable energy savings, this also decreases water consumption on the chiller by up to 60 per cent.
In a canning line, the rinser is one of the biggest water consumers. However, because the process does not significantly impact the quality of the rinse water, this water lends itself extremely well to reuse, for instance as process water for the pasteuriser, in the can spraying system or for the conveyor lubrication system. Up to 90 per cent of the rinse water can be treated and reused, thereby reducing the line’s freshwater consumption by up to 50 per cent.
In some cases, the pasteuriser needs to have an additional cooling zone at the discharge in order to bring the containers down to the required temperature. Instead of dispersing the released heat into the environment by way of an evaporative cooling tower, a heat pump can be used to send it back into the pasteuriser. That reduces consumption of both primary energy and water on the machine. Whether such a solution makes sense will depend on the relationship between the infeed and discharge temperatures of the containers.
Measures that can be retrofitted
- heat pumps for recovery at the pasteuriser and bottle washer;
- VapoChill cooling tower;
- fresh water pressure regulator for the bottle washer;
- summer/winter switch for the bottle washer (spray volume linked to the temperature of the fresh water);
- circulation of the cooling water for the vacuum pump in the Contiflow and on the warm deaeration unit during thermal product treatment; and
- EquiTherm Coldfill for cold filling beverage cans.
For more on how to reduce water consumption, click here.
