From pilot to production

Scaling heat transfer solutions without sacrificing performance 

Author: Jamie Zachary 

Scaling a thermal processing solution from concept to commercial scale is a complex task, especially in the case of free-flowing bulk solids. While early-stage laboratory or pilot testing can demonstrate whether a solution is feasible, it is essential to understand how heat moves through granular materials – and how the material behaves while in motion – to ensure consistent thermal performance during commercial operations. 

Many thermal systems fall short at this stage due to changes in residence time, bulk solid flow behaviour or heat transfer efficiency that do not scale linearly. For this reason, industry experts say scaling up heat exchange processes demands more than just enlarging equipment. It requires a structured approach grounded in material science, process modeling and field validation. 

“We’ve repeatedly seen how variables such as particle size, moisture and heat sensitivity can impact flow patterns at scale,” says Scott Harris, Regional Director, Americas at Solex Thermal Science. “Without accounting for these factors, systems that appear viable at lab or pilot scale can struggle in a real-world environment.” 

Why heat transfer with bulk solids requires a different approach 

Heat exchange in bulk solids differs significantly from liquids or gases. In these systems, energy is transferred indirectly — first between individual particles, then from those particles to the heat transfer surface. Because of this, particle flow consistency is as important as thermal conductivity. 

A controlled, uniform and distributed flow of material through moving bed heat exchanger equipment can help ensure all particles have equal exposure to the heating or cooling interface. Conversely, channeling, stagnation or clumping can lead to uneven temperature profiles, product degradation or fouling. 

"Understanding how material behaves in heat exchange equipment is just as important as knowing its thermal properties. That’s why scale-up needs to address both flow and heat transfer,” explains Jean-Marc Reichling, Regional Director, EMEA at Solex, who specifically highlights new applications as cases where pilot testing under real industrial conditions provides the greatest benefit.

Steps toward a scalable heat exchange solution 

An effective scale-up process typically includes a progression of analytical and physical testing stages designed to validate assumptions and guide system design. These stages may include: 

1. Materials characterization 

Tests at ambient conditions identify thermal and physical properties such as particle size, bulk density, heat capacity, specific heat, thermal conductivity angle of repose and other flow behaviours. These measurements drive important design parameters such as flow path geometry and heat transfer area. 

2. Flowability assessment 

Application-specific geometry testing (e.g., plate spacing, mass flow cones) assesses whether the material flows consistently throughout the heat exchanger. This indicates any potential for channeling, bridging or other flow limitations. 

3. Thermal behaviour testing 

In working conditions, more specialized tests can measure how the material responds to heat: 

  • Differential scanning calorimetry (DSC) identifies phase changes or latent heat. 

  • Thermogravimetric analysis (TGA) checks for moisture loss and drying rates. 

  • Shear cell testing provides data on the hopper design and discharge characteristics. 

4. Wear and material selection 

For high-temperature and/or abrasive applications, erosion testing under simulated plant conditions can help determine the materials of construction that will be capable of withstanding prolonged contact with the particles. 

5. Pilot-scale validation 

Pilot testing bridges theory and full-scale implementation. Whether in a testing laboratory or on-site, running the process at a small industrial scale can help engineers verify crucial details such as heat transfer rates, flow performance, moisture handling and control logic. These insights reduce the risk of overdesign, unexpected performance gaps due to caking or fouling or process instability at full production rates. 

A proven pathway across industries 

When it comes to heating or cooling free-flowing bulk solids, there is no compromising on product quality or process effectiveness. This is why industrial operators in industries such as fertilizers, foods, polymers and minerals need to take a well-thought-out approach when bringing their thermal processing solution from concept to full commercial production.  

Scaling up a new thermal process? Connect with our engineering team to learn how to apply these principles to your next project, or discover how our technology works to support scalable, efficient processing of free-flowing bulk materials. 


This entry was tagged Heating, Cooling, and last updated on 2025-7-7


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