Fruitmasters: integrated cooling control for DCA storage
Nijssen Koeling has extended its control system with a module for managing Controlled Atmosphere (CA)- and Dynamic Controlled Atmosphere (DCA) storage. This new module was taken into use by Fruitmasters for 57 newly built and renovated cold stores in two depots in Geldermalsen.
Fruitmasters stores around 9 million kilos of top fruit, soft fruit and stonefruit under DCA conditions. Optimal conditions need to be established for each fruit variety, even for each batch - depending on factors such as the fruit size, the (micro)climate in the orchard and the degree of ripeness during harvest. Constant monitoring, measuring and adjustments are required to keep conditions consistent and fruit quality at an optimum condition for each room.
Frequent gas analysis
The Fruitmasters' depots are provided with three ULO gas control stations. Using measurement hoses, each station analyses the atmosphere in 20 cold stores. The control system provides individual settings in each room, for any gas and temperature storage regime. All settings are tightly controlled and any deviations from the set value points are notified to the user.
Nijssen's control system regulates all of the processes, both cooling conditions (i.e. temperature, humidity) and ULO components (i.e. gas measurements, aeration, CO2 scrubbers, nitrogen generator). Cold stores can be controlled individually or as part of a group.
Large amounts of data traffic
"The data management was one of the challenges for this set up," technical engineer Edwin Snabel of Nijssen explains. "Monitoring the conditions in all cold stores generates a huge amount of data - especially in Fruitmasters' large scale operations. Smart solutions for data traffic have been applied in the software. This means the system can control and respond quickly and efficiently."
Quicker response to deviation
"Due to extensive measuring and registering, we are now able to respond quickly to deviations," says Harry Beelen, cold store manager at Fruitmasters. "Also, it is simpler to interpret tendencies in the storage process."
Quick set up based on recipes
With around 350 settings and measurement per cold store, custom control could become rather challenging. The control therefore offers the opportunity to capture the basic conditions and for each variety and set a basic recipes for the different phases in storage. Through user friendly menus adjustment is possible on all parameters. The basic recipes are stored on the control computer, so that unlimited recipes can be defined.
Extensive data registration
All actions, alarms and log data are registered by the system and can easily be recovered for analysis. A full report of each batch is available, including detailed overviews and graphs. Of course, all information can also be printed and exported. "An extensive and accurate account of the storage process is of the utmost importance for us," says Harry Beelen. "With around 50 million kilos of fruit in storage we have a big responsibility."
Queue management creates steady energy efficient process
Besides safeguarding optimal storage conditions, the efficient use of energy is another priority. A serious reduction in energy consumption is achieved by the choice for energy efficient components and through smart control options, such as an advanced queue management.
Latest hardware platform
Usually, Nijssen uses Hitachi with Codesys runtime for its control systems. Fruitmasters chose Siemens PLC's (S7-1500 and S7-1200) and the Siemens TIA Portal. The Siemens OPC-server is in charge of the communication between the PLCs and the user friendly visualisation.
Developing the new control system, Nijssen has included the expertise of Frank van de Geijn, consultant Post Harvest Technology at Wageningen UR. Harry Beelen was also closely involved. "I am very satisfied," indicated Harry Beelen. "Nijssen has more than kept its promise. Based on our specifications they built completely new software in 14 weeks, including tests and commissioning. Plus; the system works better than expected! An excellent achievement, especially considering the size of this project."
Among the options:
- Full control of Controlled Atmosphere components (e.g. CO2 scrubbers, nitrogen generator and aeration)
- Unlimited number of cold stores to be controlled
- User-friendly control with easy menus and submenus
- Every cold store individually controllable and as part of a group
- Storage conditions automatically adjustable based on user-defined decision rules
- Queue management module guarantees steady and energy efficient process
- Universal recipe wizard
- Detailed reports and charts
- Full reporting of storage process for each batch
- Fast and efficient data processing
- Available for Codesys / Hitachi and Siemens
Completion: September 2015