Critérios de eficiência na produção industrial de clínquer para cimento Portland

Abstract

In today’s highly competitive cement industry, combined with the growing demand for sustainable production practices, enhancing the reactivity of Portland clinker has become a critical objective. This study proposes the industrial implementation of recent scientific and technological advances aimed at maximizing the formation of the alite phase in clinker. Key reactional parameters are evaluated, such as the particle size distribution of reactive silica, the rheological influence of the SO₃ and MgO balance in the liquid phase, and their combined effects on clinker reactivity and overall cement productivity. The study also compiles a set of reactional insights to support a high-performance clinker reactivity model, whose proof of concept demonstrates significant innovative potential for industrial application. In Phase 1, critical reactional triggers for maximizing the alite conversion rate in clinker were validated at an industrial scale. It was shown that SO₃ and MgO act as modulators of the viscosity and surface tension of the liquid phase, favoring the nucleation and growth kinetics of C₃S crystals. Simultaneously, the reduction in reactive silica particle size and the increase in available Ca²⁺ shifted the thermodynamic equilibrium of clinkerization toward the conversion of belite into alite. These transformations resulted in clinker with superior physicochemical properties, evidenced by lower clinker reactivity index (CRI) values, increased grinding productivity, and higher mineralogical coefficient (KM), reflecting greater friability and energy efficiency during comminution. In Phase 2, the reduction of the belite phase (C₂S) was found to be directly correlated with decreased energy consumption during grinding, with measurable gains of up to 3 kWh/t for each percentage point reduction in C₂S content in industrial clinker. Additionally, it was observed that the microstructural reconfiguration of the clinker matrix—including a reduction in belite crystal size and thinner phase boundary zones—significantly improved grinding performance and operational efficiency. This condition was confirmed through optical microscopy, chemical characterization (XRF), reactivity index testing (IRC), and mineralogical coefficient (KM), indicating the consistent formation of high-performance clinkers over the 21- month study period. Both phases converged in the development of a robust technological model for controlling clinker reactivity, grounded in compositional, structural, and operational parameters. This model offers technical support for predicting clinker behavior during the cement phase and provides practical guidelines for real-time process optimization. As a result, value was captured across multiple dimensions: enhanced physical and chemical cemen performance, improved industrial predictability, and significant reductions in variable production costs per ton.