The AI Advantage

Cement manufacturing, a cornerstone of global infrastructure, is undergoing a significant transformation driven by the need to improve energy efficiency and reduce emissions. This change comes as the industry faces mounting pressure to address its environmental footprint; it is currently responsible for approximately 8% of global CO₂ emissions. A key enabler in this transformation is a new closed loop AI optimisation (AIO) approach, which offers a fresh perspective on process control and online optimisation.

The most significant operational challenges facing cement plants today are multi-faceted, encompassing raw material availability and variability. Unpredictable volumes, inconsistent frequency, and fluctuating quality of supply lead to irregular clinker quality, reduced plant productivity, and elevated emissions. Furthermore, ageing equipment compounds these issues throughout production campaigns, as wear and tear on critical components of the cement manufacturing process progressively diminishes production capacity and process efficiency. Variability in raw material quality is particularly problematic in cement production, as it can lead to mechanical, environmental, operational, and safety challenges. Fluctuations in raw material quality directly affect the chemical reactions involved in clinker formation, which, in turn, influence the overall quality of clinker production.

Similarly, variability in the type and quality of fuel can disrupt the temperature profile and heat distribution in the kiln, causing over-burning or under-burning of clinker and adversely impacting its quality and reactivity. Additionally, changes in ambient conditions and humidity can influence the hydration reaction of the cement product and the efficiency of heat transfer during the process.

The path to a low carbon future

Decarbonising cement production centres on minimising CO₂ emissions generated during the calcination process.

A key lever in this effort is reducing the clinker factor – the percentage of clinker used in cement production. However, the two primary challenges here are maintaining throughput demand and adhering to product quality standards, both of which directly affect profitability.

Clinker factor reduction is achieved by substituting clinker with other raw materials or industrial by-products, collectively known as supplementary cementitious materials (SCMs). Examples of SCMs include fly ash, calcined clay, calcined shale, and slag cement.

While increasing the proportion of SCMs lowers the clinker factor, it often compromises cement performance, particularly mortar strength.

This issue can be mitigated by enhancing cement fineness or increasing clinker reactivity, both of which significantly impact the cement grinding process.

Higher cement fineness demands greater energy consumption to grind clinker into fine powder.

Conversely, using more reactive clinker facilitates easier grindability at higher fineness targets due to its mineralogical composition, particularly its high alite (C3S) content. This is crucial for counteracting the mortar strength reduction associated with higher SCM usage.

Alternative fuels (AF) also play a pivotal role in decarbonising the industry, as approximately 40% of cement industry CO₂ emissions stem from fossil fuel use. Introducing and sustaining AFs in the production process, known as co-processing, is vital for strengthening the circular economy.

While other decarbonisation methods aim to reduce specific gross emissions (the total amount of CO₂ emitted per tonne of cement), the adoption of AFs contributes to lowering the absolute gross emissions (the total CO₂ output) of a cement plant.

Enjoyed what you've read so far? Read the full article and the rest of the March issue of World Cement by registering today for free!

Read the article online at: https://www.worldcement.com/special-reports/26032025/the-ai-advantage/