Trade press release
15 Nov 2023
GEA equipped the multi-purpose arena in Berlin with refrigeration technology. (Photo: Stageview/Beccera)
The climate also needs to be right in the stands. GEA technology ensures a pleasant temperature of up to 21 degrees Celsius for the fans. And because the next game or another major event is never far away, the ice needs to hold up and must not thaw. After an ice hockey game, construction usually starts right away to set up for a concert, a basketball game or other events. The ice surface then disappears under 1,249 insulation panels for several hours or even days without thawing or deteriorating in quality. This is possible thanks to a real power-play combination provided by engineers, ice masters and the in-house technicians team.
The graphic shows the construction of the ice surface. You can see the pipelines as well as the ice surface on top (Photo/graphic: GEA/Cem Yücetas).
CLIMATIC GfKK – Gesellschaft für Kältetechnik-Klimatechnik mbH was the main contractor for the multi-purpose arena project in Berlin. Technical Service Manager Martin Reichmuth explains the decision to go with GEA solutions and technologies: “It was the equipment’s efficiency that tipped the scales in GEA’s favor. The overall efficiency, flexibility, wide performance range, long service intervals and an extended, best-in-class warranty led to our selection.”
Martin Reichmuth, Technical Manager Service of CLIMATIC GfKK – Gesellschaft für Kältetechnik-Klimatechnik mbH, Matthias Wiegand, GEA Compression Technologies Sales, Heat Pumps & Chillers and Helge-Andreas Dietzsch, Technical Manager House Services (from left to right) check the cooling system settings in the machine room. (Photo: GEA/Cem Yücetas)
But how do the ice masters get the icy surface to fit precisely and on time? Since the championship in Germany’s top ice hockey league, the DEL, usually begins in September each year, the preparatory work starts in mid-August. The complex process, involving numerous steps, takes almost a week.
First, the concrete floor of the arena is prepared. This includes accurately measuring and marking the area as well as cleaning and smoothing the concrete surface to create a level base. Any irregularities or dirt particles must be removed to allow for even ice formation.
Today’s refrigeration systems are based on the principle of a closed refrigeration cycle. An NH₃/CO₂ (ammonia/carbon dioxide) cascade is installed in the Berlin arena. The secondary refrigerant is CO₂, while NH₃ is the refrigerant for the primary circuit. The refrigeration circuit’s main components are the compressor, the condenser, the expansion valve and the evaporator, the refrigerant pumps and the cooling tower.
First, the gaseous refrigerant is sucked in and compressed by the compressor, with the heat generated in this process being absorbed by the refrigerant. The heated refrigerant is fed into the condenser, where it cools down at constant pressure. In the process, the refrigerant condenses, becoming liquid. In the next step, the now liquid refrigerant reaches the expansion valve. Through this valve, the refrigerant expands to a low pressure level, thus reducing the temperature. In the final step, the refrigerant flows into the evaporator, where it is returned to a gaseous state. During this process, the heat required is extracted from the surrounding environment, which cools down as a result. So in fact, cold is not being made. It is simply the removal of heat. The refrigeration cycle then starts again with the transfer of the refrigerant into the compressor.
The interface of the two circuits is the evaporator/condenser, where the gaseous CO₂, which comes from the CO₂ separator, is liquefied and the liquid ammonia is evaporated. Pumps then feed the liquefied CO₂ into the pipes (secondary circuit) in the ice surface, where it absorbs heat and returns to the separator partially vaporized. The two circuits work in tandem.
A peek under the ice. Pumps feed the liquefied CO₂ into the pipes (secondary circuit) (shown here in blue and red for clarity) in the ice surface. (Photo/graphic: GEA/Cem Yücetas)
The ice masters apply water mist using hoses fitted with fine nozzles. The sprayed water is degassed, as normal tap water – with the oxygen and carbon dioxide it contains – would lead to gas inclusions in the ice and negatively impact its subsequent quality. The hoarfrost on the concrete floor absorbs the degassed water and freezes into ice. This fine water mist is applied repeatedly over several days – ensuring each time that the water can be completely absorbed by the hoarfrost and thus freeze. A layer of ice gradually forms from the hoarfrost. Advertising foils, logos as well as the ice hockey lines and markings are applied between the layers. While these are then covered by a thin layer of ice, they naturally remain visible. At the end of the process, the ice cover is about three and a half centimeters thick, ideal for an ice hockey game. Ice hockey players need a very hard ice surface of minus eight degrees Celsius so that the puck really flies.
GEA Grasso M packages
The sophisticated design and low parts complexity combine reliability and serviceability with high efficiency. This can save significant energy, service and other ongoing costs, reducing the total cost of ownership of the refrigeration system over its lifetime. On average, the M models consume three to five percent less drive energy than their screw compressor unit predecessors. As a result, they contribute to significant energy cost savings.Thanks to the high-performance motor (speed range from 1,000 to 4,500 rpm), the GEA Grasso M packages ensure top performance with maximum energy efficiency under all load conditions. In addition, the GEA Grasso M packages operate without an oil pump, giving refrigeration plant operators the dual benefit of lower energy and spare parts costs.
Sophisticated design delivers numerous advantages
The screw compressor and drive motor are mounted on a horizontal oil separator, saving space and at the same time ensuring effective separation of the refrigerant from the oil. Thanks to its minimal oil throw rate (5 ppm) and low oil charge, maintenance costs are reduced – further bringing down the total cost of ownership.
At a glance – the highlights and technical features of GEA Grasso M packages for industrial refrigeration
GEA and the natural refrigerant ammonia
Ammonia is the most efficient and cost-effective natural refrigerant with a GWP of 0 and can generate 1.75 kW from 1 m³/h mass flow. In other words, it has a higher capacity, so less of it is required to produce the same output as alternative refrigerants. Another major advantage of climate-friendly ammonia is that, thanks to its thermodynamic properties, it can be used for both cost-effective cooling and heating. The COP (coefficient of performance) of a heat pump operating under typical conditions for a district heating network or for process heat below 100 degrees Celsius, for instance, is 40 percent higher than that of synthetic refrigerants. This translates to a 40-percent reduction in emissions, energy consumption and costs. Another significant advantage of ammonia is its long life, making it a great investment compared with other refrigerants. While other refrigerants may require customers to make a further investment for replacement or conversion to other refrigerants after ten years, an investment in ammonia is safe for the next 30 to 40 years, or even longer.
The refrigeration cycle’s main components are the compressor, the condenser, expansion valve (high-pressure float) and the evaporator), the refrigerant pumps and the cooling tower. (Photo: GEA/Cem Yücetas)
Dr. Michael Golek
Компания GEA – это один из крупнейших поставщиков для пищевой промышленности и широкого спектра других отраслей промышленности. В 2019 году ее консолидированный объем продаж составил около 4,9 миллиарда евро.