Reuse of energy reduces costs and saves resources

The challenges of the food industry
The important role of the food industry in enabling our society to meet its basic daily needs is huge. And the demands on producers are correspondingly high. The more these demands can be justified, the more challenging they become. On the one hand, we require high-quality foodstuffs that are safely and hygienically processed. On the other hand, however, these must be affordable and permanently available. This challenging combination of economic and ecological factors has now been given extra momentum by high energy prices and shortages of resources, and this means that we in the food sector must think differently and think further.

Strategies for sustainable food production
On the one side, enormous social need – on the other side, enormous energy consumption. How can we find a sustainable solution in this situation? When designing food production facilities, it is essential to precisely understand the core process of the relevant sector and to be up-to-date with the very latest technology. At foodfab, our integrated process planning expertise goes hand in hand with the integrated design offered by ATP architects engineers. This enables us to conceive and plan food processing facilities, which are sustainably commercially successful and, hence, fit for the future. In our design work for the dairy industry, the heat exchanger has repeatedly shown itself to be part of an efficient strategy for recovering heat energy. This allows us to both meet energy requirements and save energy in the spirit of protecting the climate. And the bonus represented by reducing costs should also be underlined, because this also benefits the end consumer.

The principle of the heat exchanger
Heat exchangers work according to the principle of heat transfer as a means of saving thermal energy. Put simply: Heat exchangers enable us to repeatedly reuse the energy produced by a process in a production facility. In a dairy, for example, heat sources are connected with heat sinks via a storage device. This storage device is a large tank full of water. It enables us to bridge the time between the production and the cooling of the necessary heat, whereby the water is the medium for transferring this heat. Natural density ensures that the colder water is at the bottom of the tank and the warmer water at the top.
Let us remain with the example of the dairy, which is a particularly energy-intensive facility. Because the production of milk products such as cheese involves a range of heating and cooling processes that require considerable amounts of energy. During the cheesemaking process, milk is heated to the necessary temperature using the warm – the upper – layer of water in the exchanger tank. Energy transfer leads to a cooling of the exchanger water. This is then pumped back into the lower part of the tank. The process requires perfectly laminar flows so that the warm and cold water do not mix. The cold water in the exchanger tank is then used to cool the whey produced during the cheesemaking process. This process reheats the exchanger water, which is then returned to the upper part of the tank. And we can start again at the beginning, warming the next milk in the dairy. The cycle is complete.

This example shows how we can work with the natural processes of water and energy in order to create a well-thought-out, simple, yet highly effective solution. A further example of a heat recovery system is offered by cleaning processes. Here, hot waste water from the various cleaning processes in a dairy is captured in order to use the heat energy in this waste water to heat the rinsing water. Rinsing with warm water can, for example, raise a stainless steel tank to a certain temperature in readiness for cleaning. This means that the brine only has to deal with the temperature delta that is required to reach the necessary cleaning temperature. This enables a high percentage of the required heat energy to be saved. In an industry in which production processes require huge amounts of energy, this represents an enormous saving. And this is only one of the many screws that we can turn to reduce energy consumption and, hence, not only comply with but also continuously perfect the ATP Green Deal.
In this way, the food sector is in a position to meet its needs without doing so at the expense of the environment. And this is the objective that we as foodfab consultants are intensively pursuing in dialog with key players from the food industry.