Case study: cool changes part of major dairy developments
Refrigeration energy efficiency played a major role in the development of several new dairy facilities aiming to boost production for export and domestic markets, writes the team at engineering consultancy pitt&sherry.
Growing international demand, industry consolidation and manufacturing expansion have created a market environment not seen for many years in Australia’s dairy industry, according to Andrew Buckley, national
leader – Food and Beverage at pitt&sherry. Australia’s leading manufacturers are aiming to upgrade capabilities and capacity to meet demand primarily stemming from developing Asian nations requiring milk, cheese and products for infant nutrition.
In 2012, Australian dairy exports to China increased by 17 percent compared to 2011 on the back of growing demand for milk powder, liquid milk, cheese and butter, according to a Dairy Australia report. With opportunity ripe for this growth to continue, Australia’s dairy expansion has gathered momentum around the country. In the past three years, pitt&sherry has been involved with the engineering elements of the last four major developments by Murray Goulburn Co-operative (MGC), Lion and Tasmanian Dairy Products (TDP).
Buckley says these projects reflect a promising outlook for the Australian dairy industry and through innovative and sustainable methods would substantially lift output.
“Led by a developing Chinese middle class and growing worldwide food security issues, a mix of industry consolidation and rationalisation, coupled with expansion, has created a buzz not seen in the industry for some time,” Buckley says.
A key aim of Lion’s $50 million redevelopment of its cheese manufacturing operations at Burnie, Tasmania, was to double the factory’s manufacturing capacity from 11,000 to 22,000 tonnes per year.
pitt&sherry provided civil works and services for Lion, including project definition and all statutory approvals, design and documentation of the building and mechanical services, construction management and supervision, and contract administration.
The development focused on innovation, technological advances, and current and future environmental requirements, with examination of incorporating aspects of cogeneration and trigeneration as part of the upgrade, examination of the technical feasibility, operational aspects, energy balance and financial outcomes.
Also in Tasmania, TDP’s $80 million Smithton Dairy product facility was opened in March 2013 following a rigorous design and development project timeline.
At Smithton, raw milk purchased from local farmers is processed to produce a range of high quality dried milk products, primarily for export to overseas markets in Asia and the Middle East. pitt&sherry’s involvement included concept design, engineering works, site selection and initial planning works, while also overseeing the installation, building and infrastructure design, site services, and environmental and planning approvals.
In 2013, pitt&sherry designed two state-of-the-art pasteurised milk processing plants for Murray Goulburn at Laverton in Victoria and Erskine Park in New South Wales. Both facilities, which are expected to be commissioned by July 2014, will be capable of annually supplying up to 150 million packaged litres of milk to Coles supermarkets.
As part of the Burnie upgrade, a design and technical specification of the new plant’s refrigeration services was established to maximise energy efficiency.
Refrigeration is required for production processing, including milk pre-cooling, milk storage, pasteurisation, soft ripened and pressed cheese making, cool rooms and climate control (HVAC) – all critical components of the cheese making process.
The initial specification was for a traditional central plant layout, comprising an engine room, evaporative condensers, flooded receiver, compressors, accumulators and chilled water storage tank.
Essentially the refrigeration plant provided ammonia cooling of chilled water and glycol circuits that provided refrigeration to the cheese plant. Following further analysis, the decision-making process was steered towards adopting a package refrigeration plant as opposed to a central refrigeration plant.
Energy-efficient systems will also reduce the running costs of both plants for Murray Goulburn. Built-in heat exchangers on the air-handling units pre-condition incoming fresh air with the exhaust air, providing a significant saving of energy use for ventilation and the plant’s oil-less refrigeration compressor technology has greater energy efficiency than conventional refrigeration.
According to Buckley, a facility such as Smithton commonly takes two to three years to complete. “To accommodate the milk supply contracts we had the plant operating and producing powder in just 14 months,” he says.
The Murray Goulburn plants were also delivered under demanding time constraints by developing one above-ground design for duplication across both sites. This reduced not only the design timeline, but also the building construction time and cost. The design, which incorporated the world’s latest processing technology, was flexible in accommodating for future expansion, while also being easily adaptable to the second site and set up for simple disassembly at plant end-of-life.