Precision in Proportioning: The Critical Role of Accurate Material Handling in High-Performance Blended Cement Production

The shift towards blended cements is a defining trend in the modern cement industry, driven by the dual imperatives of enhancing sustainability and achieving specialized concrete performance. As cement producers increasingly incorporate Supplementary Cementitious Materials (SCMs) like fly ash, slag (GGBS), limestone, and natural pozzolans, the precision of material handling—from storage to proportioning and blending—becomes absolutely paramount. At Delta Ducon, with over a century of experience in pioneering bulk material handling solutions, we understand that the ultimate quality and consistency of high-performance blended cements are intrinsically linked to the accuracy and reliability of the systems that dose and combine their constituent ingredients.

Inaccurate proportioning of these diverse materials is not a trivial matter. Unlike traditional Portland cement production, where the primary component is clinker, blended cements rely on a synergistic combination of multiple materials, each with unique physical and chemical properties. Deviations in the precise ratios of these components can significantly impact the final product's performance characteristics, including:

• Compressive Strength: Incorrect SCM content can lead to underperforming or overly reactive cement.

• Durability: The long-term resilience to chemical attack, freeze-thaw cycles, and abrasion can be compromised.

• Setting Time & Workability: Variations can cause issues for end-users, leading to construction delays or difficulties in concrete placement and finishing.

• Color & Aesthetics: In architectural applications, inconsistent blending can result in undesirable visual variations.

  
  

Achieving the full potential of blended cements requires a material handling system engineered for exceptional accuracy and homogeneity. This is where Delta Ducon’s innovative solutions, exemplified by our SmartBlend™ / ROTOFeed™ system, deliver unparalleled results.

Delta Ducon's SmartBlend™ System: Precision Engineered for Blended Cements

The challenges of accurately dosing and blending multiple fine powders require advanced technology. Our SmartBlend™ system, often utilizing the proven ROTOFeed™ technology, provides a "combined dosing, blending, and conveying system" designed for the on-line production of blended cements. This integrated approach ensures that each component is introduced with exceptional precision, leading to a continuous, instantaneous, and homogenous blend.

Key features of the Delta Ducon system that ensure precision in proportioning include:

• High Accuracy Dosing: The system can incorporate high-accuracy Gravimetric loss-in-weight control, achieving dosing accuracies of ±0.5% per feed. Even in volumetric mode, a continuous feed rate accuracy of ±2.0% is maintained. This level of precision is crucial for guaranteeing consistent product quality.

• On-Line Blending: Materials converge immediately from their respective SmartFeed™ units into a single line, where liquid additives can also be introduced at the same point. This eliminates the need for a separate, subsequent mixing process, simplifying the plant design and ensuring a highly efficient blend.

• Homogenous Mix: The technology is designed to achieve a fully homogeneous mix of the final blended product, with Coefficient of Variation (CV) values often less than 3%, meeting or exceeding industry standards and those of batch-type mixing.

• Flexibility and Control: The system offers significant flexibility in production range, component ratios, and operational modes, capable of handling rates from 10 to 150 TPH and conveying distances up to 500 meters. This adaptability allows producers to meet diverse market demands efficiently.

  
  

Showcase: The CEM 3 Project – A Testament to Precision

A prime example of expertise in action is the CEM 3 blended cement production project at a cement Producer in the UK. The need to introduce a CEM 3 (cement/slag blend) range, combined with the quest for the most elegant and advanced solution for a fast-track project, were key drivers.

The project involved the conversion of an existing coal bunker for the new CEM 3 production, utilizing the SmartBlend™ technology. Two ROTOFeed™ units, each rated at 30-60 tph (75 tph design), formed the core of the "SmartBlend" system for the on-line blending of Cement/GGBS and a liquid additive. This installation was the first of its kind within the Producers group globally, underscoring its innovative nature.

The project drivers emphasized efficiency, simplicity, lower energy consumption, and overall cost-effectiveness when considering the total package, including a smaller building and reduced maintenance. Delta Ducon’s solution delivered on all fronts:

• Guaranteed Quality Assurance: The precise dosing capabilities of the ROTOFeed™ units ensured that the Producer could meet their stringent quality requirements for the CEM 3 product.

• Efficient Blending: The system achieved a highly efficient and homogeneous blend directly in the conveying line.

• Cost Savings: The simpler design, elimination of a separate mixing stage, and smaller footprint contributed to a lower overall cost compared to conventional processes.

• Operational Flexibility: The system allowed for variable rates and production runs, from small batches direct to trucks to continuous operation for bulk silo storage.

  
  

The project, pre-tested and validated by the Producers technical center, demonstrated the superior performance and reliability of the SmartBlend™/ROTOFeed™ technology in a demanding, real-world blended cement application.

The Broader Impact of Precision Material Handling

Investing in accurate material handling systems like Delta Ducon's SmartBlend™ offers cement producers a multitude of benefits beyond just product quality:

• Reduced Waste: Precise dosing minimizes the overuse of expensive SCMs and clinker, optimizing raw material consumption.

• Lower Operational Costs: Simpler plant designs with fewer process stages lead to less maintenance and lower running costs.

• Enhanced Sustainability: Efficient use of SCMs is key to reducing the carbon footprint of cement production. Accurate blending ensures these materials are used to their full potential.

• Increased Market Responsiveness: The flexibility to produce various blended cement types and batch sizes allows producers to quickly adapt to changing market demands.

• Process Simplification: Combining dosing, blending, and conveying into a single stage streamlines operations.

  
  

Conclusion: Your Partner for High-Performance Blended Cements

As the cement industry continues its evolution towards more sophisticated and sustainable blended products, the role of precision in proportioning cannot be overstated. The ability to accurately and consistently combine multiple components is fundamental to achieving the desired performance, quality, and economic benefits of these advanced cements.

Delta Ducon, with its proven SmartBlend™ / ROTOFeed™ technology and a legacy of engineering excellence, stands ready to partner with cement producers worldwide. Our systems are designed not just to move materials, but to do so with an unparalleled level of accuracy and reliability, ensuring that your blended cement production meets the highest standards of quality and efficiency.

To learn more about how Delta Ducon can optimize your blended cement material handling processes, contact our experts today.