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Ammonia proves its advantages in various industrial use

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Industrial refrigeration is an important part of our developed society. We depend on it to make our modern lifestyle possible. Ammonia, as a natural refrigerant, has proven its reliability in industrial refrigeration for over 120 years. It is also an ideal refrigerant from a climate protection point of view, as it contributes neither to ozone depletion nor to global warming. These advantages are the reasons why Ammonia is used in a wide range of different areas on an international level everywhere around us. Below, we present four versatile use cases which illustrate Ammonia’s capabilities and strengths.

 

Swedish manufacturer of heat exchangers uses Ammonia-based heat pump for its own requirements

Alfa Laval is one of the world's largest manufacturers of heat exchangers. At its production site in Lund, Sweden, the company has been using an innovative Ammonia-based heat pump system since 2013. Waste heat from the component production process is used as the source energy to the pump system. The system covers almost the entire heating and hot water requirements of the factory and corporate headquarter.

The heart of the system is a flooded evaporator, combined with a U-turn separator. It absorbs the thermal energy of the oil cooling system, which is heated to around 28°C in the factory’s production operations. After compression, the high-pressure system conducts the heat in the condenser to a closed heating-water circuit, thus boosting the water temperature to 65°C. This system works with a comparably low amount of only 40 kg of Ammonia. Jesper Olsen, Application Expert Refrigeration of Alfa Laval emphasizes that this sustainable procedure saves the environment around 140 tons of CO2 per year. It thus reduces Alfa Laval`s need for expensive district heating by 3,700 MWh – which is an enormous cost factor.

 

Scottish salmon processing company uses Ammonia-based cold store for holding incoming raw material

Young’s Seafood is the UK’s number 1 fish and seafood business. The company looked for an economically advantageous and future-proof alternative when it came to replacing their existing HFC/R22 refrigeration system which they need as a cold store for holding incoming raw material prior to processing and dispatching. They found the ideal solution in an air-cooled Ammonia refrigeration system designed and installed by Star Refrigeration with components of BITZER Kühlmaschinenbau. The refrigeration plan is based on a combination of low-pressure receiver technology, EC-fan and PLC control technology. The new refrigeration system was being installed in the existing one even before the old system had been dismantled, so that the conversion did not interrupt production. As Phil Moxon, Factory Engineering Manager, from Young’s explains, due to its special design the new system is 15 to 20 per cent more efficient than traditional systems with HFC-technology.

 

Norwegian District supplies environmentally friendly heat with Ammonia-based heat pumps

The city of Drammen, Norway, invested in a district heating plant, based on heat pumps to utilize the heat in the fjord water. The facility includes the world’s currently largest ammonia based high temperature heat pump. The thermal energy of the fjord water is transferred to a closed circuit and successively heated to 90°C by three two-stage heat pumps connected in series and designed for 65 bar. This system supplies about 70 per cent of the district heating network with inexpensive and environmentally friendly heat. Each heat pump requires a filling quantity of only 1,000 kg Ammonia.

Andres Liang, production manager at Drammen Fjernvarme confirms that managing to boost the heat from the fjord to a useful temperature level in such an efficient way is a remarkable achievement, which is probably only possible with Ammonia. Its sustainability is considerably higher than possible alternatives such as waste burning. Also, it consumes about 15 per cent less energy than conventional district heating systems based on synthetic refrigerants.

 

German hospital saves big by soucing Ore water to deliver heating via Ammonia heat exchanger

The district hospital in Freiberg, Germany, is located in the Ore Mountains above an old silver mine. Water in tunnels 200 meters below the hospital flows at a constant temperature of around 14 °C throughout the entire year. Johnson Controls designed a two-stage Ammonia heat pump and power plant that uses this water as the energy source to deliver heating to the hospital. The heat energy stored in the water is transferred to the Ammonia circuit by a plate heat exchanger at 200 m depth.  At the heating centre on the surface, the temperature of the water is raised by a heat pump cycle. A gas-fired combined heat and plant then generates the electrical energy for operating the heat pump.

Achim Welz, Chief technician of Kreiskrankenhaus Freiberg reports that with this sustainable and cost-efficient solution, the hospital can cover about 80 per cent of its heat requirements and along the way save heating costs of about 350,000 euros per year.