Supporting reliable performance when transitioning to alternative coals or blends. 

In an evolving energy market, coal-fired power stations must increasingly adapt to changes in fuel availability, cost, and environmental requirements. Switching to lower-rank fuels or introducing alternative coals can impact combustion behaviour, equipment life, heat rate, and emissions.

HRL’s Coal Switching Service helps generators understand the feasibility, risks, and operational implications of fuel changes, ensuring continued reliability, efficiency, and compliance.

Switching fuels is not a simple procurement decision. Each coal type behaves differently in terms of combustion performance, slagging and fouling tendencies, milling behaviour, and emission characteristics.
Without proper assessment, fuel changes can result in:

• Reduced plant efficiency and increased heat rate
• Accelerated wear or unexpected component failures
• Emissions noncompliance
• Poor combustion stability, slagging or fouling

HRL combines advanced modelling, diagnostic testing, and deep combustion engineering expertise to derisk fuel switching and support successful implementation.

A comprehensive assessment of how alternative fuels will affect plant performance.

Activities include:

• Review of plant documentation and fuel specifications
• Review of combustion impacts, including slagging and fouling risks
• Thermodynamic modelling of alternative coals using Thermoflow software
• Assessment of impacts on coal use, air requirements, flue gas temperatures, auxiliary power, and emissions
• Review of impacts on key equipment including boiler, mills, attemperators, heat exchangers, air heater, fans, dust collection systems, and ash handling
• Identification of key equipment constraints
• Identification of recommended plant modifications and operational controls (where required)

Implemented only when Stage 1 identifies specific risks or areas where additional testing or validation is beneficial.

Typical activities include:

• Coal blending
• Plant trials with proposed fuels
• Plant modifications
• Plant performance testing and combustion tuning
• CFD modelling to assess combustion behaviour in detail
• Fouling and slagging investigations

Ensuring stable, efficient longterm performance as fuel conditions evolve.

Activities include:

• Implementation of monitoring tools such as EUtech systems
• Ongoing optimisation of combustion and furnace temperature distribution
• Support for longterm reliability, efficiency, and emissions compliance

Assessment of nine alternative coal sources using calibrated modelling and KPI analysis to identify suitable options and provide operational risk mitigation strategies.

Investigation using CFD and thermodynamic analysis to resolve reheater overheating caused by flowinduced hot spots, enabling design improvements and reducing failure risk.

Onsite testing and modelling to improve combustion behaviour under different fuel conditions, supported by advanced PF distribution and diagnostic tools.

• Proven capability across Australia and Southeast Asia
• Deep expertise in combustion engineering, diagnostics, and modelling
• Advanced laboratory, testing, and monitoring tools
• Practical, commercially focused recommendations for reliable implementation