FROM peeling potatoes to pasteurising milk, beverages and canning foods, steam plays a pivotal role in the food and beverage industry.
Dennis Williams, commercial director at expert operations and maintenance service provider Associated Energy Services (AES), which serves the steam and boiler sector, describes steam as a tried and tested method for cooking, baking, coating, and preparing foods – as well as for drying or dehydrating everything from milk to fruit, coffee, and fish. Steam also plays a central role in cleaning and sterilising bottles, cans and equipment – as well as in packaging and shrink-wrapping.
A recipe for safety
Due to the proximity of steam to food during the production process, one of the most critical factors is safety. Williams explains: “This requires carefully considered water treatment using food-grade chemicals. Temperature is also important. Dairy processing, for example, requires constant steam pressure to ensure that equipment such as spray driers can operate efficiently.”
Efficiency
Williams says service level agreements (SLAs) between major food producers and AES clearly stipulate key deliverables in terms of throughput, efficiency, and effectiveness.
In the dairy industry, for example, raw materials must be processed as quickly as possible. Milk has a very short shelf-life – and wastage of product purchased from farmers increases production costs.
“With one of our dairy clients, the SLA specifically addresses steam pressure requirements. These inform the dryness fraction and the temperature of the steam. This key control input determines if further control inputs – such as pressure-reducing stations – are required to ensure that steam pressure remains within the control range of the pasteurisers and other equipment,” he explains.
In addition to meeting stringent specifications set out in each SLA, AES also provides its Remote Monitoring System (RMS) which enables clients to monitor temperatures, pressures and flows.
“In this way, clients can see what is happening on our side of the fence with regards to the steam control parameters,” he says.
Williams notes that a client’s steam requirements and operational tolerances depend on the sophistication of the energy plant in use – and the specific products being manufactured. Bespoke solutions are needed: “For example, a dairy producing only milk will have different requirements to a facility producing cheeses and yoghurts,” he observes.
Seasonality is another key challenge in dairy and other food-producing facilities, where it is imperative to ensure that there is no failure in the steam supply during peak periods when the energy plant is running at maximum capacity.
Eco-friendly energy
“Pressure from retailers and consumers to curb prices and minimise environmental impact places additional pressure on food and beverage producers,” says Williams: “Until now, most have operated coal-fired boilers – or relied on less environmentally-friendly fuels such as heavy furnace oil, which has a high sulphur content. AES constantly monitors technology trends, together with the quality and availability of alternative fuel sources – such as biomass and biogas – to support clients looking to minimise their carbon footprints.”
To this point, one of the company’s clients – a large dairy in the Eastern Cape, recently installed a second boiler fuelled by biomass.
More efficient fish processing
Another client in the fishing industry recently worked with AES on a turnkey project that included a major upgrade of its boiler house format, structure, and technology, as well as the installation of four new boilers.
The replacement of 78-year-old boilers at one of the client’s key food processing plants has not only proven to be a very worthwhile investment but has driven the transformation of the company’s entire production process.
This turnkey project, one of the largest in the sector and region, effectively positions the company to meet the growing demand for affordable protein in the future.
This investment formed part of the company’s production process transformation at this plant, with the switch from flue gas drying to steam drying resulting in a higher-quality protein product. The innovative steam plant upgrades implemented by AES also kick-started the client’s journey towards reducing carbon emissions, aiming to meet its target of cutting carbon emissions by 50% by 2030 and achieving ‘carbon zero’ status by 2050.
To date, plant particulate emissions from this fish processing client have been reduced by an impressive 42%, with overall operational efficiency increasing by 15%.
