Refrigerating and air conditioning systems in the states of the Russian Federation are starting to show their age. A large proportion of the machines date back to between the 1930s and the 1960s, are technically worn out and consume disproportionate amounts of energy. The systems are uneconomical to run, with high costs for maintenance and repairs.

"We estimate that over the next few years, up to 90% of these systems will have to be replaced by new machines that offer a long service life and high energy efficiency", says Franz Kaltenbrunner, Board member at eurammon, the European initiative for natural refrigerants. "One clear trend to emerge here is the use of natural refrigerants such as ammonia, carbon dioxide or hydrocarbons. Their good properties constitute a viable solution for replacing the outdated refrigerating systems in the former Soviet states."

The use of natural refrigerants offers potential for saving energy by up to 30%, thanks to their high energy efficiency. Ammonia for example is acknowledged to be the most efficient refrigerant, which also has a positive effect on the carbon balance. In addition, the industrial production of ammonia, carbon dioxide & co. is less energy-intensive and therefore less costly than that of synthetic refrigerants – advantages that operators, refrigeration system engineers and planners are showing signs of appreciating to an increasing extent.

Energy-efficient milk processing

The milk factory Sitnikov in Siberia is a major processing company in East Russia. To replace the previously used synthetic refrigerants, refrigeration is now to be converted to an environment-friendly, economically efficient solution. The operator defined the technical capability in precise terms, specifying the need for a refrigeration system that cools 80 m³ of water from 8 to 2°C every hour for the processing and storage of dairy products.

The core of the new refrigerating system consists of two screw compressors by Bitzer, installed as a twin pack on a joint rack. The 586 kW ammonia plant has a charge of 300 kg and it’s design operating conditions are an evaporation temperature of -2°C and a condensing temperature of +35°C. Use of the highly efficient refrigerant ammonia has cut power consumption by 30% compared to systems with synthetic refrigerants. The operator deliberately chose two small screws compressors instead of one large machine so that production can be maintained if one of the two compressors be out of operation. The twin compressor solution also facilitates more precise capacity control, reaching the full COP (Coefficient of Performance) of 4.46 even for an utilisation rate of only 50%. Other important components in the system include an economiser, a flooded evaporator with pumped refrigerant circulation, condenser and programmable control. The compressor oil is cooled using a water cooled heat exchanger. The new refrigerating system has been running free of any interference since mid 2008.

Natural refrigeration of meat and sausages

The Volkovysk combine is one of the 10 largest meat processing factories in Belarus. Every year around 60,000 t of meat are processed here to make products such as mincemeat, sausages and meatballs. More than 300 meat and sausage products are cooled with the natural refrigerant ammonia.

Unrivalled in environment protection

"Together with their energy efficiency, natural refrigerants are convincing above all with their environment-friendly characteristics", says Franz Kaltenbrunner from eurammon. "Their global warming potential is either zero, as with ammonia, or negligibly low. They also preserve the ozone layer. Natural refrigerants are thus simply unrivalled from the point of view of the climate."

Source: eurammon

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