#neverstopINNOVATING

Turning fine limestone into value is not just a market-driven innovation — it’s a strategic move to reduce quarry waste, optimize calcination, and contribute to global sustainability goals. With the SYNTHESIS® Fine Lime HP kiln, QualiCal transforms what was once a limitation into a performance advantage.

Why Fine Lime Matters

Traditionally, regenerative PFR kilns operate with limestone fractions between 40 and 90 mm. However, more than 50% of quarried limestone often falls below this size due to natural breakage during blasting, handling, or crushing. In conventional settings, this smaller material is discarded or relegated to lower-value uses.

QualiCal’s Fine Lime Production Experience redefines this limitation as an opportunity — allowing producers to recover and valorize finer fractions (as small as 15–20 mm), reducing material waste at source and supporting the responsible use of natural resources in line with the UN SDG 12.2 target.

The Challenge of Fine Limestone in PFR Kilns

Operating a PFR kiln with fine limestone presents a higher pressure drop across the shaft due to the reduced free volume between the stones. This condition typically:

• Reduces airflow,
• Distorts heat distribution,
• Increases risk of bridging and dust buildup,
• Leads to lower kiln productivity and poor lime quality.

The HP Solution: High Pressure Operation by Design

To overcome these technical constraints, QualiCal has developed the HP — High Pressure Operation Mode for its Synthesis® kilns. This is not a retrofit: it is the result of a long-term R&D effort embedded into the original kiln design, engineered from the start to safely operate at nominal pressures up to 500 mbar.

Key Design Features Enabling HP Operation:

• Reinforced kiln shell: Designed to withstand high operating pressures with total structural reliability.
• Engineered process valves: Air/Fumes Valve (AFV), Shaft Closure Valves (SCV), and Lime Discharging Valves (LDV) components optimized for high-pressure operation.
• Variable kiln geometry: Rounded preheating zone ensures stable pressure; rectangular discharge area prevents bridging.

• High-density lance grid: Capillary fuel distribution assures uniform combustion and calcination even under fine lime conditions.

• CARGO® feeding system: Minimizes segregation and ensures homogenous shaft loading.
• METRO® 3D Shaft Level Indicator: Provides ultra-precise material height monitoring for optimal discharge logic.
• Triple drawer discharge system: Balances extraction across each shaft to maintain flow and reduce buildup.

The Benefits

Thanks to HP operation, the Synthesis® kiln ensures good quality lime using limestone down to <20mm

• More uniform heat distribution, supporting consistent lime reactivity and quality.
• Reduced waste at quarry, transforming unusable fines into premium quicklime.

A Concrete Step Toward NEXT GENERATION LIME

The Synthesis® Fine Lime HP is a perfect expression of QualiCal’s vision: combining process excellence, design innovation, and digital intelligence to shape a more resource-efficient, energy-smart, and sustainable lime industry.

QualiCal for the Sustainable Developement

Our planet has provided us with an abundance of natural resources.But we have not utilized them responsibly and currently consume far beyond what our planet can provide. We must learn how to use and produce in sustainable ways that will reverse the harm that we have inflicted on the planet.

This solution responds directly to both technical challenges and global sustainability goals, including:

• Target 12.2 — “… achieve the sustainable management and efficient use of natural resources.”
• Target 12.5 — “… substantially reduce waste generation through prevention, reduction, recycling and reuse.”