Rivalea is an Australian agri-food company based inCorowa NSW, with activities in feed milling, livestock production and meat processing..
The processing facility uses an ammonia refrigeration plant, which initially had an annual power consumption of 5.164 GWh. There were numerous opportunities for energy savings identified by Minus40 at Rivalea. Some of these were implemented in early 2013, with estimates of a 10-30% energy saving for the refrigeration plant. The improvements are outlined in this study.
Compressors produce a lot of heat – heat which is wasted in typical refrigeration plants. On a meat processing site such as Rivalea, there is high demand for hot water, including wash-down water. At these sites, the “waste heat” is valuable.
To recover the heat, it was necessary to install a high stage discharge desuperheater, and also heat recovery oil coolers onto two high stage screw compressors. Only two of the compressors operate for long enough periods to make heat recovery feasible.
The solution uses two stages of heat recovery; first the water is fed through the discharge gas desuperheater, and then it is fed through the oil coolers for further heating.
Variable speed drives for fans and compressors were added so that motors were run only to the power required, rather than always running at full power. Monitoring was installed for all variable speed drives.
The Rivalea upgrade project benefitted from the Minus40 whole-of-project expertise to attract the following benefits:
- NSW Government Energy Saver Program – this covered part of the cost of the initial audit, which established the feasibility of the resulting upgrade.
- Low Carbon Australia (now Clean Energy Finance Corporation) – this provided low-cost financing for the upgrade work.
- AusIndustry Clean Technology Investment Program – a co-contribution towards the upgrade.
MINUS40 Project Services
MINUS40 assisted Rivalea with the following project services:
- Project identification, conceptual design and feasibility study
- Detailed engineering design
- Provision of functional descriptions for plant control logic
- Tender specification preparation
- Tender management process
- CTIP grant application assistance
- Project measurement and verification (upon project completion)
Throughout the project, MINUS40 assisted Rivalea in acquiring the following financial project assistance:
- OEH Energy Saver Program: Subsidised 70% of feasibility study
- Clean Technology Investment Program: $268,810 CTIP Grant