Fonterra’s Project InteGreat involved the installation of four new processing plants at its Edendale site.
Edendale has been in operation for 133 years and is New Zealand’s oldest dairy factory. Milk from more than 1000 Southland farms is processed at the site, which employs 670 staff.
Fonterra coined the project name to reflect its desire to integrate new opportunities at the site, in line with its lengthy production history.
InteGreat also refers to the key challenge faced by Fonterra during the expansion activities. Fonterra had two options: install a new boiler to meet the steam demand, or implement energy recovery projects to reduce steam demand. The company chose the latter option, and needed to determine initiatives that would meet the steam demands of the additional plants without installing a new coal boiler or impacting the existing site operations.
Project decisions were complicated by a tight time-frame: investigation began in June 2014 with the goal of having the new plants operational by August 2015.
Historical data was gathered to determine a maximum steam demand for the existing plants. The project team estimated what the steam demand would be with four new plants in operation and then compared that against the maximum steam capability of the on-site boilers.
That left a gap equivalent of about 9 tonnes an hour on average or 13 tonnes an hour in maximum demand. Fonterra’s challenge was to find energy reduction initiatives to address that gap.
Initiatives have included new heat recovery from chillers, hot evaporator water and heated water distribution circuits around the site to provide hot water to various plants on site or pre-heat different streams, as well as optimising plant to efficiently use and re-use heat and water.
Integrating different plants on site has enabled balancing heat demands and sources from different plants. Approximately $2.7 million was invested in energy efficiency initiatives, compared to the projected $20-$25 million for a new boiler.
Given the tight timeframe and the complexity associated with adapting plants that are in operation, Fonterra commissioned the InteGreat heat recovery projects in stages.
Heat recovery improvements required tie-ins and cut-ins to existing plant systems, and needed to be scheduled during plant off-periods.
To date the performance of the Edendale improvements has achieved the targets. There were no issues meeting steam demand between September and December 2015, when demand is typically highest.
Energy improvements at Edendale will help meet Fonterra’s target to reduce its energy intensity by 20 percent by 2020, from a 2003 baseline. The company forecast avoiding additional use of approximately 17,000 tonnes of coal at the site, therefore avoiding the carbon emissions of approximately 23,500 tonnes of CO2eq per annum by pursuing the option of heat recovery rather than installing a new boiler. In addition to delivering significant environment benefits this has also resulted in increased efficiency and reduced operating cost for the site.
The four new plants have increased processing capacity at Edendale by 25 per cent to 16.4 million litres of milk per day and have widened the firm’s product offerings from the site.
The Large Energy User Initiative of the Year award category is sponsored by EECA Business