Italian compressor manufacturer Dorin is showcasing what it calls the “largest” transcritical CO2 (R744) compressor on the market at Chillventa 2024, with plans to launch the 8-cylinder CD1000 range, driven by electric motors ranging from 500 to 750HP, in the second half of 2025.
According to Massimo Casini, President of Shanghai Dorin Compressor Sales and Asia Area Coordinator, the reciprocating compressor, with a displacement of 308m3 per hour (181.4ft3 per minute), will come in two versions ‒ semi-hermetic and open, with the open unit allowing the use of medium voltage motors.
“Industrial heat systems require megawatt capacities, creating the demand for a larger compressor,” Casini told NaturalRefrigerants.com. “The 750HP unit allows us to increase the use of CO2 in the industrial heat pump sector.”
“To replace one gas boiler in China, we supplied 90 CO2 heat pumps,” he remarked. “However, using 10 to 20 compressors in parallel creates limitations.”
At the event, Dorin is also exhibiting its newly released CD700 range CO2 compressor, offering capacities from 120‒180HP with a displacement from 74–100m3 per hour (43.6–58.9ft3 per minute).
Casini noted that Dorin offers a series of transcritical CO2 compressors to cover all possible market applications, including mobile air-conditioning, supermarkets and industrial processing.
The company’s compressors incorporate an external discharge manifold, which separates the high-temperature CO2 compressed gas from the body of the compressor and the oil. According to Casini, the design, which comes from the company’s nearly 30 years of experience working with CO2, increases the safety and life of the compressors.
Dorin won the 2021 AHR (Air-Conditioning, Heating and Refrigeration) Award in the refrigeration category for its up to 100HP 6-cylinder CD600 transcritical CO2 compressor, which at that time nearly doubled the refrigeration capacity available in a single unit.
CO2 or ammonia
Industrial processors often employ ammonia (R717) refrigerant systems. However, Casini told NaturalRefrigerants.com that Dorin sees applicability for CO2 in the industrial sector in countries where laws restrict the use of ammonia and hydrocarbon refrigerants and in places like Italy that lack trained technicians to handle the installation and maintenance of ammonia systems.
Other factors playing into the decision, Casini said, include initial costs, maintenance and refrigerant costs, operational efficiency and the availability of components.
According to Lucy Luo, Lead Sales Representative at Shanghai Dorin Compressor Sales, Dorin sold 1,000 transcritical CO2 compressors in China in 2023, which tripled its sales since opening the office in 2018.
Hydrocarbon compressors
Casini noted that Dorin is investing in hydrocarbon high-temperature heat pump technology for outlet temperatures up to 150°C (302°F).
“We have a new range of ATEX-certified compressors which incorporate our external discharge manifold,” Casini said. “This technical solution spreads the use of natural refrigerants without compromising the reliability or life of the system.”
Dorin launched its first hydrocarbon system in 2012. Its HEX series comes in models from two to eight cylinders, suitable for propane (R290) and propylene (R1270), with nominal capacities from 0.5 to 90HP.
“The 750HP compressor allows us to increase the use of CO2 in the industrial heat pump sector.”
Massimo Casini, President of Shanghai Dorin Compressor Sales
