Successful ammonia applications in wineries

By Sabine Lobnig, Dec 06, 2011, 17:51 2 minute reading

50-70% of winery electricity consumption is related to refrigeration, hence the need to find the most economical refrigerant to reduce electricity costs. With proven superior efficiencies when compared to synthetic fluorocarbons, ammonia has been used for many years in chillers for large wineries. As shown below several efficient ammonia refrigeration systems and effective brine and heat recovery applications are to be found in Australia and New Zealand.

In wineries, wine or juice may be heat exchanged directly with the evaporating/expanding refrigerant at the evaporator in which case the operation is described as “direct expansion”. Alternatively a secondary coolant (a “brine”) may be heat exchanged with the evaporating refrigerant and then distributed around the winery to cool juice or wine.

Ammonia refrigeration coupled with brine systems

Brine systems have higher power usage for a given cooling effect when compared with direct expansion operation; however, they have some advantages. Stored brine can be used to balance against peak demand and brine is relatively cheap, safe and non-volatile and therefore can be more easily reticulated around a winery than a primary refrigerant. Water with a freezing-point suppressant is commonly used as the brine. The freezing–point suppressant may be a watersoluble liquid or salt.

Adelaide winemakers for example, has an ammonia plant system comprising two compressors – Hasegawa VKL62A and Werner CP-61 and two condensers – White and BAC – providing 100 tonnes of cooling capacity distributed through 40,000 litres of circulating brine to almost all tanks.

Latest winemaking technology include ammonia

Yalumba’s Moppa winery (South Australia) has incorporated the latest in winemaking technology: three ammonia compressors and a pumping system circulate liquid ammonia through the must chillers, "rack-and-return tanks" and fermentation vessels. The control system works out the required load and directs which should be the lead compressor and what the optimum settings are, based on how much cooling is needed for the required fermentation rates.

The refrigeration system is highly efficient, with the option of off-peak loading to reduce both electricity costs and power consumption through maximised compressor efficiency. Also, the hot return ammonia gas heats the water used for washing tanks throughout the plant.

New Zealand winery heat recovery success

Yealands Estate, a privately owned winery in Marlborough, uses both cooling and heating processes. Using heat recovery, this environmentally-conscious winemaker takes waste heat and uses it elsewhere. This has helped cut its energy costs by 50% and boosted their brand at the same time. The company saved 120,000 kWh in one year thanks to heat recovery, and 135,000 kWh thanks to the large compressor of its refrigeration plant.

Advice on winery refrigeration

The Grape and Wine Research and Development Corporation (GWRDC) has funded the Australian Wine Research Institute (AWRI) Commercial Services to look at how Australian wineries can improve refrigeration efficiency. As part of the initial stage of this project a reference guide was produced.
This document contains a succinct overview of winery refrigeration concepts, together with 19 improvement opportunities, and is available for download.

Industrial refrigeration equipment companies such as GEA Grasso and ARTech Solutions produce equipment for use with all refrigerants including packaged ammonia chiller equipment for use in wineries.


By Sabine Lobnig

Dec 06, 2011, 17:51

Related stories

Sign up to our Newsletter

Fill in the details below