Danfoss secures a major design win for a landmark CO₂ refrigeration project in China

Monday, 1 July, 2013

Dalian, China July 25, 2013. The global climate & energy leading company Danfoss is pleased to report that its award winning valve station for industrial refrigeration, called the ICF Flexline™, recently achieved a major milestone in China. The Flexline™ family of valves were extensively applied in a landmark CO2 refrigeration project at the scallop & sea cucumber processing centre of the Dalian Zhangzi Island Fishery Group.

The Zhangzi Island is located in the north end of the Yellow Sea, 56 nautical miles from the continent and free from pollution. The natural environment of the island is well suited for aquaculture, which combined with bottom-breeding technology, yields high quality seafood. Zhangzi Island's products are widely recognized as organic, green and pollution-free. Every year, Dalian Zhangzi Island distributes approximately 100 million seeds into the sea. At the bottom of the cultivation area there are so many marine creatures, that it is often referred to as a "seabed bank". Three main products, Yezo scallops, sea cucumber and abalone, all grow very well in this type of environment.

Overlooking the Zhangzi Island, a large silver building will certainly grab your attention. This building, that many say resembles a large ship, is the newly constructed seafood processing centre of Dalian Zhangzi Island group. This building combines seafood processing and cold storage. After comprehensively considering safety, the environment, and efficiency, the Zhangzi Island group decided to use CO2 as the refrigerant for this project. Danfoss was subsequently selected as the valve supplier due to our industry leading CO2 technology, vast experience with CO2 and our high-quality products.

For this project, one major objective was to protect the environment since Zhangzi Island is located in the southern China Changshan Islands in the clean and pollution-free area. For the sake of environment protection, the environmentally-friendly refrigerants ammonia (R717) and CO2 (R744) were chosen to be used for this project. 

Safety and energy savings were also major priorities for this project. With only 14.36 KM2, the Zhangzi Island is highly concentrated and populated. Safety of the local residents is always a primary concern. In the newly developed seafood processing centre, the freezing plant utilizes a NH3/ CO2 cascade system for refrigeration, which lower the NH3 charge amount by over 90% and limits the NH3 refrigerant inside of the refrigeration control room, fully satisfying the safety requirements of Zhangzi Island group. The cold storage plant utilizes a CO2 brine system and uses the abundant sea water as the cooling medium for the high level ammonia refrigeration. The setting up of the condenser heat recovery appliance prior to the cooling process, realized a good balance between safety and environment protection. For big scale industrial refrigeration region of China, the Zhangzi Island new processing plant is the first to combine both CO2 cascade & brine systems. This is one reason why it is now considered a benchmark project in the green journey for China industrial refrigeration.

The reliability of the refrigeration system is an important element of the Zhangzi Island project, since the island is far from the mainland and transportation is limited. Seafood processing depends heavily on reliable refrigeration systems. This is the main reason why Danfoss CO2 solutions and components were used for the Zhangzi Island project. With leading TDR technology, Danfoss AKS 4100U series radar liquid level sensor was adopted for liquid level controlling of the NH3/ CO2 cascade system, working together with the ICM series motor control valve for precise control of the refrigeration liquid level control. The feeding line of the freezing room uses the Danfoss premier product ICF series valve station, which compressed the installation area by 2/3 and reduced the welding time by 80%. The newly launched SVL series refrigeration components were also widely used.

For the fishing and seafood processing industry, refrigeration is a key requirement for practically the entire process. Accurate and stable low temperature control is a crucial in pre-processing, pre-cooling, quick freezing, post-processing and refrigeration. With vast experience in this field, Danfoss provides many leading marine companies across the globe with both components and technical support. Danfoss is rapidly becoming the leading refrigeration supplier to the fishery industry due to our reliable, efficient, and environmental-friendly refrigeration solutions.

General modularization solution:
SVL line components + ICS industrial control valve + ICF valve station
• Direct welding form is used without flange, reducing the leakage risk by up to 80%
• Using just two basic valve housings - a straightway and an angleway - the platform offers 5 different functions

Line Components:
• The backbone of the platform is the common housing which is available as angle- or straightway. All five function modules: stop, regulating, stop/check, check and filter fit the same housing
• They all have the same high specification making selection, system design and mounting simple and trouble free

Valve station:
• Only two welding ensures the safety and fast installation with an improved efficiency
• Innovative modular design can have the function modules assembled in the single housing

Control valve:
• The special V-port design in the ICS throttle cone ensures optimum regulation characteristic to pilot operated main valves even at partial load
• The plug-in module adopts QPQ technology to realize excellent environmental adaptation

Danfoss industrial refrigeration Flexline™ valves were widely applied in this project