A NEW South Wales red meat processor has implemented a staged heat recovery system that reduces natural gas consumption, improves refrigeration efficiency and removes the need for a major boiler upgrade.

The project has shown that meaningful energy savings, improved refrigeration performance and reduced greenhouse gas emissions can be realised without major disruption to plant operations.

The system installed at Gundagai Meat Processors recovers waste heat from refrigeration condensers and compressor oil coolers through a closed loop network that preheats boiler feed water from 15°C to 50°C.

Measured results show average gas savings of about 30 GJ per day, together with more stable boiler operation, reduced condenser loading, and significant operating      cost reductions.

The impact of heat recovery on boiler fuel consumption at the plant was estimated to save about $135,000 a year, reducing gas use by about 30pc. It means the $450,000 cost of installing the technology could be repaid in three years, while considerably reducing the plant’s carbon footprint.

The GMP Heat Recovery Project, backed by the Australian Meat Processor Corporation, has successfully demonstrated that significant reductions in natural gas consumption can be achieved by recovering waste heat from existing refrigeration systems using commercially available technology.

A future industrial heat pump will lift the water temperature further to approximately 88°C, pushing gas displacement toward 100pc and creating one of Australia’s most advanced integrated industrial heat recovery systems.

“This project offers a practical, scalable and commercially attractive model for the Australian red meat industry’s transition to lower emissions and improved energy efficiency,” the AMPC project report says.

The project supports AMPC’s Decarbonisation Pathway by combining passive heat recovery with future industrial heat pump integration — maximising the recovery of available waste heat before any active, energy-intensive temperature lifting is introduced.

Key benefits demonstrated by the project include:

• Significant, lasting reduction in natural gas consumption and operating cost
• Deferred or avoided capital expenditure on boiler and condenser upgrades
• Improved refrigeration condenser capacity and reduced refrigeration energy use
• Lower carbon emissions
• A commercially practical, replicable pathway toward industrial electrification.

Heat recovery should be considered an integrated energy system rather than a single piece of equipment, AMPC’s project report says.

“The staged approach here offers a model that can be replicated across other meat processing facilities,” it said.

Energy costs are one of the most significant operational challenges facing Australian meat processors. Refrigeration remains the largest electrical load, while natural gas continues to supply the majority of process heating.

Hot water is essential for sterilisation, sanitation and cleaning, so boiler performance directly affects production reliability, food safety and operating cost.

Historically, the considerable heat rejected by refrigeration systems through evaporative condensers has simply been discharged to atmosphere.

At the same time, processors face rapidly rising gas prices, growing pressure to cut emissions, ageing boiler infrastructure, and rising expectations around energy efficiency and sustainability             – all of which have increased interest in waste heat recovery.

Industrial heat pumps can achieve large temperature lifts but often carry high capital cost and electrical demand. GMP’s staged approach instead extracts as much useful energy as possible from existing refrigeration equipment first, before introducing active heat pumping —improving overall efficiency and reducing lifecycle cost.

Prior to implementation, GMP faced operational and financial challenges common throughout the Australian meat processing industry. Its 2 MW hot water boiler supplying sterilisation, carcase processing, wash-down and sanitation was regularly operating over its maximum capacity as production increased, especially in winter when incoming water temperatures averaged 15°C.

During peak demand, maintaining the required 82°C steriliser temperature across the plant became increasingly difficult, occasionally interrupting production. Engineering assessments concluded that continued expansion would require replacing the existing boiler with a new 2.5 MW unit, at an estimated capital cost of $400,000 and around the same time GMP experienced a 50pc increase in gas pricing on contract renewal.

This combination of rising fuel costs and looming capital expenditure prompted GMP to look for an alternative to simply increasing boiler capacity.

Capital expenditure avoidance

One of the project’s most significant outcomes has been avoided capital expenditure.

GMP had anticipated replacing its 2 MW boiler with a 2.5 MW unit at an estimated cost of $400,000. Following successful commissioning of heat recovery project, this upgrade is no longer required. Similarly, the 400kW increase in effective condenser capacity defers the future need for additional refrigeration condenser infrastructure as production expands; a minimum 1000 kW condenser installation would typically cost in the order of $240,000.

These avoided costs substantially improve the project’s overall financial return, on top of the ongoing utility savings.

The GMP Heat Recovery Project demonstrates that staged heat recovery is technically proven, commercially viable and readily scalable. Wider adoption across the Australian meat processing industry has the potential to significantly reduce operating costs, improve plant efficiency, lower greenhouse gas emissions and strengthen the industry’s long-term sustainability and competitiveness, AMPC’s report says.

As energy prices continue to rise and the Australian meat industry moves towards lower-carbon operations, recovering waste heat should become a fundamental part of refrigeration system design rather than an optional enhancement, it suggests.

“Every gigajoule of waste heat recovered is a gigajoule of natural gas that no longer needs to be purchased or combusted.”

Source: AMPC