Decarbonizing spray drying

When a longstanding customer, a large European dairy, came to GEA with high ambitions with regard to reducing CO₂ emissions at all operational levels, GEA experts immediately set to work. Reductions are particularly challenging to achieve when operating spray drying plants, due to the complexity of the production sites and the high temperatures required for operating the spray-dryers themselves, which is generally generated by the burning of fossil fuels. To deliver an effective solution, a collaborative approach would be required.

The challenge: significantly and profitably reduce CO₂ emissions in spray drying

As a GEA customer for a number of years, it was straightforward to organize a joint investigation into possible options for decarbonizing the plant. This was carried out by means of a holistic energy audit conducted in 2018. The subsequent analysis highlighted the difficulty of abating large amounts of CO₂ emissions by means of profitable investment, but also presented less obvious opportunities that would prove it is not impossible.

The solution: integration of a tailor-made high-temperature heat pump system

Having identified energy consumption as an area of significant importance, GEA experts worked closely with the customer to design a tailor-made solution which could achieve outstanding reductions of natural gas consumption and therefore CO₂ emissions. Through a combined heating and cooling process delivered by a high-temperature heat pump system, the GEA AddCool® solution became the first installation of its kind in a dairy production plant globally.

As GEA designed both the heat pump and the integrated heating and cooling system, the customer was able to benefit from stringent performance guarantees over a six-year operating period. This ensured that the spray drying plant operation, from powder production to powder characteristics, was not affected by the change in utility system while achieving the desired CO₂ emissions savings.

The design and guarantees were validated by an independent energy advisor, selected directly by the customer. This provided valuable insight into the project, highlighting the importance of good collaboration at all levels for retrofit projects of this scale.

The results: outstanding decrease of CO₂ emissions and operating costs in spray drying

The GEA AddCool® system provided several benefits to the customer:

• Reduced demand of natural gas for heating of primary air of 610000 Nm3/y, equal to a 55% reduction compared to the previous operation. This results in the yearly abatement of 1300 t/y of CO₂ emissions while operating with electricity from renewable energy sources.
• Electricity savings on the existing chiller installation, achieved by providing 270 kW of useful cooling while delivering high-temperature heat to the dryer.
• Reduced load and noise from the existing cooling tower, achieved by precooling the waste water from the system.
• Clear overview of the current and historical performance of the system by means of GEA InsightPartner monitoring solution.

Thanks to the careful integration and accurate prediction of performance, the GEA AddCool® system passed the site performance test at the first attempt. Its performance is being continuously monitored through the GEA InsightPartner solution and is on track to deliver the promised savings within a forecasted payback time of six years.

The future: Decarbonize spray-drying

The GEA AddCool® was the first installation of its kind and proves that heat pumps can be successfully integrated into the spray-drying process when the right collaboration and skillset is secured. The success of this achievement is yet another example of GEA’s commitment to engineering for a better world, and as a result the company is planning future installations of this proven technology in spray drying plants worldwide.