CALCINED CLAY

Shaping Cement’s
low-carbon future

Scroll to explore

FFuulllleerriisswwhheerreeccllaayyccaallcciinnaattiioonntteecchhnnoollooggyyaannddddeeeeppcceemmeenntteexxppeerrttiisseeccoommeettooggeetthheerrttooppoowweerrtthheellooww--ccaarrbboonnttrraannssiittiioonn--pprroovveennaatttthheewwoorrllddssllaarrggeessttaannddEEuurrooppeessffiirrssttiinnssttaallllaattiioonnss..DDeelliivveerriinngg::

Lower CO₂ emissions (>30%)

Lower CO₂ emissions (>30%)

Lower capital & operating costs

Lower capital & operating costs

Quality product with cement-grey color

Quality product with cement-grey color

High system availability

High system availability

Proven at industrial scale

Proven at industrial scale

INTRODUCTION

FROM CLAY TO
LOW-CARBON CEMENT

Abundant resources. Significant clinker reduction. Lower costs. With 56% of cement's CO₂ tied to limestone calcination in clinker production, reducing the clinker factor is the single biggest lever for emissions reduction. As a supplementary cementitious material (SCM), calcined clay can replace up to 40% of clinker - driving high-quality, low-carbon cement at lower cost. It's effective. It's sustainable. And it's available worldwide.

But unlocking that potential at industrial scale is not straightforward. It demands precise thermal activation technology, reliable color control, and deep process expertise - and the margin for error is thin.

That's where Fuller comes in. With proven flash calcination technology, reliable color control, and a comprehensive lab-to-plant pathway backed by long-term service expertise, we give cement producers the confidence to invest - and the results to prove it. We're not planning for scale. We're already there - and just getting started.

calcined clay introduction image

The Challenge

CALCINATION Complexity
CONTROLLED

Why is industrial-scale clay calcination still rare, given its proven benefits? Because most producers face a web of interconnected challenges: clay variability from deposit to deposit, color control that makes or breaks market acceptance, energy efficiency that determines your business case, and emission limits that vary by region. Get any one wrong, and the project stalls.


Controlled calcination for Fuller means an integrated calciner system where every component - from dryer crusher to cooling cyclones - is engineered to work together. Consistent activation. Permanent color control. Maximum heat recuperation. Reliable strength development. Full regulatory compliance.


It also means providing a clear pathway from initial clay testing through to full-scale production - whether you're evaluating calcined clay for the first time or ready to commission your plant.


Whatever your starting point, we've built the system - and the expertise - to make it work.

Color Variation

Color Variation

Greymax™ Control

Greymax™ Control

Calcined clay typically turns red due to iron oxidation - a dealbreaker for market acceptance. Our patented Greymax™ process delivers permanent cement-grey color, regardless of iron content.

Energy Costs

Energy Costs

Heat Recuperation

Heat Recuperation

Traditional cooling wastes energy - or compromises color with water quenching. Our patented air-quench cooling recovers heat efficiently while preserving product color, cutting total energy costs up to 50% of clinker production. No compromises. Just results.

Clay Variability

Clay Variability

Test Before You Invest

Test Before You Invest

Not every clay deposit is viable - and discovering that after committing capital is a costly mistake. At our Dania laboratory and pilot plant, we confirm suitability before you invest - from raw material evaluation to pilot-scale production. Confidence first, then capital.

Emissions Compliance

Emissions Compliance

Proven Abatement

Proven Abatement

Strict emission limits shouldn’t stand in your way. Our proven expertise helps you predict emissions with precision and design the right solution to ensure full compliance with even the strictest regulations.

Clay Calciner System

Tailored Calciner System.
Optimized Substitution Rates.

Our clay calciner design is based on years of research and development, backed by extensive process expertise to optimize clinker substitution while maintaining cement quality. The key: heating clay to its activation temperature destroys the crystalline structure, creating an amorphous, highly pozzolanic material with high surface area - ideal for clinker replacement. Our system is engineered to hit that activation window precisely, every time. The result: a highly consistent product that enables higher clinker substitution rates than kiln-produced alternatives.

The process begins with the dryer crusher, specially designed for clays with up to 40% moisture content. Using hot waste gases from the preheater, it dries and crushes in one operation. Material then enters the 2-stage preheater/calciner, where clay is activated under tightly controlled conditions - delivering consistent product quality and reliable emission control. After calcination, the clay passes through a dedicated reducing zone where red hematite is converted to grey magnetite, then through cooling cyclones where our patented air-quench process locks in the cement-grey color permanently while recovering heat back into the system.

calcined clay flowsheet

Fresh Clay Feed

The system accepts a wide range of clay types and mineralogies with up to 40% moisture content - providing flexibility to source from local deposits. Clay availability worldwide is one of calcined clay's strongest advantages over traditional SCMs.

Preheater Cyclones:

2-stage preheater/calciner where clay is activated under tightly controlled conditions. A cyclone at the calciner outlet separates gas and material. Tight process control delivers consistent activation - resulting in uniform product quality and reliable emission control.

Fuel Input

Any traditional fuel type used in a clinker system – as well as most waste and alternative fuels - can be fired in the calciner, reducing both carbon footprint and operating costs.

Reducing Zone

Our patented Greymax™ process transforms red hematite to grey magnetite in a dedicated reducing zone. Oxidizing flash-cooling in the next stage locks in the cement-grey color permanently - a two-step process proven with high-iron and non-kaolinitic clays.

Calcined Clay Product

Highly reactive, amorphous calcined clay with high surface area - ideal for clinker replacement. Because the flash calciner delivers a more consistent product than a kiln, it enables higher substitution rates: up to 40% (or more) clinker replacement while maintaining cement quality.

Dryer Crusher

Specially designed for clays with up to 40% moisture content. Hot waste gases from the preheater dry and crush in one integrated operation, reducing energy consumption from the start.

Cooling Cyclones

Patented atmospheric air-quench cooling serves a dual purpose: it locks in the grey color from the reducing zone while maximizing heat recovery by preheating combustion air for the calciner. The result – cutting energy costs up to 50% compared to clinker production, with no compromise on color.

Fresh Clay Feed

The system accepts a wide range of clay types and mineralogies with up to 40% moisture content - providing flexibility to source from local deposits. Clay availability worldwide is one of calcined clay's strongest advantages over traditional SCMs.

Preheater Cyclones:

2-stage preheater/calciner where clay is activated under tightly controlled conditions. A cyclone at the calciner outlet separates gas and material. Tight process control delivers consistent activation - resulting in uniform product quality and reliable emission control.

Fuel Input

Any traditional fuel type used in a clinker system – as well as most waste and alternative fuels - can be fired in the calciner, reducing both carbon footprint and operating costs.

Reducing Zone

Our patented Greymax™ process transforms red hematite to grey magnetite in a dedicated reducing zone. Oxidizing flash-cooling in the next stage locks in the cement-grey color permanently - a two-step process proven with high-iron and non-kaolinitic clays.

Calcined Clay Product

Highly reactive, amorphous calcined clay with high surface area - ideal for clinker replacement. Because the flash calciner delivers a more consistent product than a kiln, it enables higher substitution rates: up to 40% (or more) clinker replacement while maintaining cement quality.

Dryer Crusher

Specially designed for clays with up to 40% moisture content. Hot waste gases from the preheater dry and crush in one integrated operation, reducing energy consumption from the start.

Cooling Cyclones

Patented atmospheric air-quench cooling serves a dual purpose: it locks in the grey color from the reducing zone while maximizing heat recovery by preheating combustion air for the calciner. The result – cutting energy costs up to 50% compared to clinker production, with no compromise on color.

With lower capital costs compared to a new clinker line, our clay calciner system is designed to maximize your return on investment.

Default alt text

COMPARISON

YOU CAN ACTIVATE CLAY IN A KILN – BUT THE RESULTS SIMPLY AREN’T AS GOOD.

Our flash calciner delivers precise temperature control, efficient heat exchange, and a more consistent product. The result: highly reactive, amorphous calcined clay with high surface area - enabling up to 40% (or more) clinker substitution. A rotary kiln produces less reactive clay, typically allowing only 15–25% substitution.

  • >20% lower fuel consumption than a rotary kiln
  • 30–40% clinker substitution vs 15–25% with a kiln
  • Higher quality due to more consistent calcination
  • Greater fuel flexibility for burning waste fuels
  • Smaller footprint and lower capital cost for a new system

Already have an available kiln? A new calciner delivers the best results, but a kiln conversion can reduce your upfront capital cost. We'll help you evaluate the right option for your site.

Calcined Clay Solutions.

Built for every challenge.

Permanent Color for Market-Ready Cement

Grey cement is the market standard. But calcined clay naturally turns red from iron oxidation to hematite. Our patented Greymax™ process solves this by transforming red hematite to grey magnetite in a dedicated reducing zone, followed by oxidizing flash-cooling that locks in the grey. Proven with high-iron and non-kaolinitic clays - even the most challenging feedstocks.

Maximum Efficiency. Minimum Fuel Costs.

Our patented atmospheric air-quench cooling maximizes heat recovery by preheating combustion air for the calciner - without compromising color or incurring water-quenching losses. Hot waste gases dry incoming clay, further enhancing efficiency. The result: energy costs savings up to 50% compared to clinker production.

Any Fuel. Full Flexibility.

Any traditional fuel type used in a clinker system – including most waste and alternative fuels - can be fired in our calciner. The system is designed for full fuel flexibility, accommodating refuse-derived fuels alongside fossil fuels to further reduce carbon footprint and operating costs.

Precise Dosing for the Perfect Mix

Calcined clay, limestone, and clinker are precisely dosed into ball mills using our industry-leading PFISTER® FRW rotor weigh feeders and SLF belt weigh feeders. Accurate proportioning is critical for consistent LC3 product quality and optimized clinker substitution rates.

Expert Process Control at Your Fingertips

Our ECS/ControlCenter empowers operators to manage calcination and deliver consistently high-quality product. Granular parameter views, open programming adjustable to your site, sensor outputs, feedback loops, and trending - data-driven interventions that mitigate issues before they become problems.

Proven Abatement for Full Compliance

Strict emission limits shouldn’t stand in your way. Our proven expertise helps you predict emissions with precision and design the right solution to ensure full compliance with even the strictest regulations.

End to end support

SUPPORTING YOUR PATH TO LOW-CARBON CEMENT.
EVERY STEP OF THE WAY.

Default alt text

From Project Planning to Long-Term Performance

From clay testing and tailored plant design to installation, commissioning, and long-term support - we optimize your system for maximum substitution rates and minimum OPEX. Once running, our expert service team provides ongoing monitoring, maintenance, and process optimization - with full OEM flowsheet support across every aspect of your process.


With Fuller, you're not just investing in a calcined clay plant - you're gaining a trusted partner for every step of the way.

Our Service Portfolio

From initial clay testing through to long-term operational support - comprehensive services across every phase of your calcined clay project.

Testing & Simulation

Pilot plant at Dania (R&D centre) for SCM activation and color control.

  • Process simulation
  • Laboratory testing
  • Quality trend reviews
  • Clay feasibility studies
  • Reactivity optimization

Design & Commissioning

Full plant design and commissioning from the OEM team.

  • System engineering
  • Installation supervision
  • Performance testing
  • Start-up support

Online

Digital tools to keep reliability high and OPEX low - from process control to real-time condition monitoring.

  • ECS Process Control Solution
  • Online Condition Monitoring (OCM)
  • Plant Line Agreement
  • SiteConnect™
  • ECS/UpTimeGo™

On-Site

Expert support from the team that designed your equipment. OEM knowledge across every aspect of your process.

  • Post-commissioning
  • Production/maintenance
  • Training
  • Clinker substitution optimization

Spare & Wear

Never wait on the parts you need. Tailored packages for your specific equipment and operating conditions.

  • First-time/2-year package
  • Inventory management
  • Extended warranty

Test Before You Invest

CONFIRM
YOUR CLAY'S VIABILITY

With Full Chemistry, Mineralogy, and Reactivity Testing & Analysis

Not all clays are equal. A clay's viability as a clinker substitute depends on its chemical and mineralogical content, how amorphous its structure is, particle fineness, strength development, and emissions. Committing capital without confirming these factors is a risk no producer should take. At our Dania R&D centre in Denmark - one of the world's most advanced facilities for raw materials in cement production - we help you confirm that you have a suitable clay source and the right equipment design to process it. Our laboratory services include full chemistry, mineralogical analysis, and clay reactivity testing. A pilot-scale calcination system is also available for full quality and strength testing of the blended cement product. The results go beyond pass or fail - you receive detailed insights to guide your project design and optimize your investment.

Default alt text

Encouragingly, most clays we've analyzed in the lab show moderate or high potential. However, there have been a few that proved unviable. That's why testing is invaluable. Pre-screening enables us to disqualify the worst materials, whether because the emissions are too high or due to inadequate strength

Niels Christian Dodensig Lundgaard, Head of Lab and Green Cement Testing

The path forward

FROM SAMPLETO SCALE

Whether you're evaluating your first clay source or scaling to full commercial production, Fuller has the technology, the testing infrastructure, and the project experience to take you from where you are to where you need to be. The question isn't whether calcined clay already works. It's when you'll start scaling into a low-carbon future.

Default alt text

Case Studies

Calcined Clay
Proven at Industrial Scale

CBI Ghana - World's Largest Clay Flash Calciner

CBI Ghana

Delivering low-carbon LC3 cement to an entire nation - at half the CO₂ of conventional OPC

0+TPD

Capacity (400,000+ tpa)

-0%CO2

vs current practices

0%Energy

less than clinker

0%Clinker

Replaced with calcined clay

CBI Ghana, alongside major shareholder Heidelberg Materials, commissioned the world's largest clay flash calciner to reduce dependency on expensive clinker imports. Fuller supplied the complete calcination system - including color control, heat recuperation, precision feeding, process control, and packing.

  • All process & product quality guarantees fulfilled
  • LC3 cement (Supacem) delivered to customers nationwide
  • Clay sourced locally, ~100 km from plant
  • Designed beyond CBI's own capacity - to accelerate industry adoption

The plant produces both LC3-45 and LC3-60 cement, crafted with 40-55% locally sourced materials. With process related emissions for the calcined clay of just ~80 kgCO₂/t, equivalent to 90% less than clinker, CBI Ghana's LC3 cements also deliver higher compressive strength from 7 days onwards, with enhanced durability.

CBI Ghana
Our Supacem LC3 cement is already being delivered to customers nationwide, offering lower CO₂ emissions, excellent strength development, and enhanced durability.

Kobby Adams, Commercial Director, CBI Ghana

Vicat France - Europe's First Industrial-Scale Clay Flash Calciner

Vicat France

Proving that even challenging, high-iron clays can produce cement-grey product at industrial scale

0TPD

capacity calcined clay

-0%CO2

at plant dispatch

0 CO2 Saved

tons/year

0%Compliance

strictest EU standards

Fuller delivered Europe's first industrial-scale clay flash calciner installation for Vicat at their Xeuilley plant. The project tackles non-kaolinitic, high-iron smectitic clay - a challenging feedstock requiring Greymax™ color control to achieve consistent cement-grey product.

  • ~600 tons produced for cement certification (6–8 month approval)
  • Supports compliance with France's RE2020 low-carbon regulation
  • Vicat evaluating additional calcined clay installations
  • Operating since 1853 - now leading Europe's decarbonization

The installation includes full emission controls (scrubber, RTO, SCR) meeting the strictest EU standards, alternative fuel capability using refuse-derived fuels, and saves 48,500 metric tons of CO₂ annually.

Vicat France
Fuller proved to be the right partner for this pioneering project. Fuller's technical expertise and responsive support helped us navigate the challenges of bringing Europe's first industrial-scale calcined clay plant online.

Vicat Project Team

Talk to Our Calcined Clay Experts

Whether you're exploring calcined clay for the first time or ready to scale, our team is here to help you take the next step.

Downloads

Brochures

Calciner System for Clay Activation

Improve your productivity and reduce CO2 emissions

21.01.2026 |

 1.32 MB |

 English

PDF
Calcined clay
Service Agreements for Calcined Clay Plants

Get more from your investment with bespoke expert services; custom packages to best match your plant’s requirements.

21.01.2026 |

 442.52 KB |

 English

PDF
Calcined clay
Test Before You Invest - ICR, August 2023

16.01.2026 |

 849.76 KB |

 English

PDF
Calcined clay