Planet-friendly dairy processing plants deliver cost and energy savings
07 Sep 2020
Dairy processing is nothing if not diverse, with its unique mix of traditional practices, like the maturation of cheeses, combined with the latest in automation. And it’s exactly this diversity that makes this sector such an ideal candidate for switching to sustainable plant solutions. Robert Unsworth, Global Technical Sustainability Manager, GEA Heating & Refrigeration Technologies, explains how dairy processing facilities can save money and reduce their environmental footprint by adopting sustainable solutions.
Where to begin?
RU: Often, the road to expansion and development is paved with inter-departmental demands and conflicting requirements – but if a facility can get the utilities and processing teams working together to a common goal (i.e. significant cost and energy savings), then the most amazing transitions can be achieved. Get the experts in as early as possible in the process and there is less likely to be fallout later since the solution can be more closely aligned to expectations from a very early stage.
If a dairy processing plant wants to introduce or switch to a sustainable solution, does it matter if it’s milk, yogurt, butter or cheese that’s being processed?
RU: Not in the slightest. In fact, it doesn’t matter if you process different dairy products in the same facility or in entirely separate locations – the only difference is the time and temperature required for each process; you just need to ensure your sustainable solution(s) can meet these requirements.
For example, in a typical milk processing plant the liquid is usually pasteurized at 72 to 74 degrees Celsius for around 15 seconds, then cooled to 2 degrees C for storage. In yogurt processing the milk is heated to either 85 degrees C for 30 minutes or 95 degrees C for 10 minutes, then cooled to 42 degrees C to allow culture growth and finally to its storage temperature of 4 degrees C.
What’s the technology driving this more sustainable approach to dairy processing and what about return on investment?
RU: In each case, the heat is extracted from the product and lifted to a higher temperature via a highly energy-efficient heat pump. This technology is rapidly becoming the solution of choice in the drive for a carbon-neutral future, to meet ever-stricter environmental regulations while enabling dairy and other food processors to reach their own sustainability goals and reduce operating costs.
When a heat pump is combined with a refrigeration unit, both cooling and heating are achieved, turning one-time use into a continuous cycle and lowering energy costs by 30 percent or more. That’s a significant savings when you consider that within the food, dairy and beverage industries, up to 60 percent of energy usage goes to heating and cooling. Let’s face it: these sectors rely heavily on massive refrigerators and anything cooled generates heat – and of course heat is energy.
Seeing a return on investment (ROI) sits alongside sustainability as a goal for every plant. This all depends on a few key points for comparison – such as the average cost of energy, for example. The higher the unit price of the energy sources before the new solution are introduced, the quicker a sustainable plant will achieve its ROI.
Finding the right partner to help in identifying the best solution and how to get the most out of it
RU: Another key success factor is a combination of selecting the right plant – and using it in the most efficient way – and even before that, selecting the most experienced and knowledgeable partner to help get the very best out of that plant. What’s the difference between piston and screw compressors, for example? One achieves the highest efficiency at high speed, the other at low speeds. Which do you choose? Do you need both? The questions could be endless, but the right people will devise the best sustainable solution to provide you with the quickest ROI.
Are these solutions future-proof?
RU: Aside from the desire by dairy plants to lower their energy consumption and operating costs, there is the inescapable fact that boilers are an endangered species. Targets for cutting emissions are tightening and, in our lifetimes, the use of fossil fuels such as gas and oil will become all but obsolete. Restrictions will impact all sectors of the food industry including dairy processing. Consider,for example, the ban on extracting water from natural sources such as rivers. The mantra reduce, re-use, recycle is gaining massive traction. This is where new technologies come into their own: extracting waste energy and re-using it to reduce or even negate the need for additional energy sources and outdated equipment like boilers.
What else can processors do to improve their efficiency and reduce costs?
RU: Sustainable solutions are not always solely about new equipment; often there is the potential to maximize an existing plant to improve operational efficiency while still meeting production objectives. For GEA this is the crux of our Holistic Engineering Solutions (NEXUS) program which integrates process and utilities (refrigeration and heating) solutions, helping dairy processing plants understand how best to reduce their energy footprint and running costs without compromising output or the bottom line.
