Concrete

Refractories: ‘Tech’ing Up!

Published

3 years ago

October 12, 2022

admin

Refractory failure is considered the most critical upset in a kiln operation. Considering the importance of refractories in the cement making process, ICR delves into the various types of refractories, their operations, challenges and the efforts taken by cement manufacturers in keeping up with innovations and automation of refractories for more efficient processes.

Cement is the most consumed man-made product across the globe. The modern civilisation owes a lot to the contribution of cement and concrete as a building material for construction of bridges, buildings, roads, dams, tunnels, and tall structures which are being used by the people everywhere in every walk of life. Manufacturing process of cement involves high temperatures. The combustion of limestone, clay or other materials to form clinker is an extremely energy intensive and temperature intensive process. This high-temperature reaction takes place inside a reactor called a kiln.

To contain the temperature inside the kiln on a continuous basis and to make the manufacturing possible on an industrial scale, Refractories play a very important role. A refractory lining inside the reactor maintains the temperature range of the reactor metal structure within a tolerable limit. This lining, also known as refractory, also inhibits the heat flow from inside of the reactor to outside. Thus, it helps in conserving the energy, which makes the cement manufacturing process productive and profitable.

There are two major purposes of refractories in a cement manufacturing unit:
To contain the high temperature or heat generated during pyroprocessingTo insulate the reactor and prevent the heat from dissipating in the environment

The special demands of cement manufacturing have always required specialised refractories – especially now, when more and more alternative fuels are used.

Types of Refractories

The special demands of cement manufacturing have always required specialised refractories – especially now, when more and more alternative fuels are used. There are two main types of refractories: castable and brick, each with distinct advantages and disadvantages.

Castable Refractory: This refractory comes in a powder form and is mixed with water on-site. Before the mixture can be put in place, anchors are installed. These Y-shaped anchors are similar to rebar in cement; they help give the castable lining its strength. Once these anchors are in place, the cement-like mixture is pumped into the lining of the rotary kiln, and allowed to cure for several days.

Brick Refractory: Brick is fired in a furnace under tightly controlled conditions that allow it to achieve better properties than a similar composition castable refractory.

Castable refractory has a similar material cost to brick. However, brick installation is much more labor intensive, as each brick is individually installed. This makes the overall cost of a brick lining more expensive than castable. While brick refractories are slightly more expensive than castable refractories, bricks do not require anchors, and their quality is superior. When processing a highly abrasive material, brick refractory is advisable most of the time, as castable does not have the durability to stand up against abrasive materials as well as brick.

Besides lower overall cost, the advantage to using a castable refractory in a rotary kiln is that it is usually easily patched when a problem is encountered. Down time is typically minimal, because the problem area can be cut out and new refractory poured into the cavity.

The disadvantage to using a castable refractory in a rotary kiln is that it is very susceptible to installation problems. When a castable refractory is expertly installed, it can nearly match the quality of brick.

But if installed incorrectly, there can be a considerable difference in quality, and the life of the refractory can be severely compromised.

The disadvantage to brick refractory is that it is kept in place much like a roman arch: bricks are held in place by the pressure of the other bricks pushing against each other. When a problem is encountered, typically the failed brick needs to be replaced, but when one brick is relying on the bricks around it to hold it in place, often one cannot replace just one brick, and whole sections of the refractory must be replaced. Unlike castable refractory, the repair of a failure in brick refractory is much more involved.

Need and Function of Refractory in a RotaryKiln
Cement rotary kilns are kilns that conduct pyroprocessing. It is a machinery in the cement manufacturing plant that is used to heat materials to high temperatures in a continuous process. The kiln body is a cylinder vessel with a certain degree of tilt to the horizontal level. Raw materials are fed into the vessel from the upper end and moved to the lower end, being stirred and mixed relying on the inclination and rotation of the kiln. The kiln burner produces a lot of heat by burning fuel. This kind of heat is usually transferred to materials through flame radiation, hot gas convection, kiln brick conduction, etc., which causes the chemical reaction between raw materials and finally forms a clinker.

Rotary kilns can be divided into cement kilns, metallurgical and chemical rotary kilns, lime rotary kilns and so on. Cement rotary kilns are used for calcining cement clinkers in the cement plant, which can be divided into dry cement kilns and wet cement kilns. Metallurgical and chemical rotary kilns are mainly applied in the metallurgical industry. As for the lime rotary kiln, it is the main equipment for calcining active lime and light burned dolomite used in iron and steel plants, ferroalloy plants, calcium carbide plants, and magnesium metal plants.

The cement rotary kiln is mainly composed of a cylinder, supporting device, drive gear, refractory lining, catch-wheel device, kiln head sealing device, kiln tail sealing device, kiln hood, and other components. On the cylinder, there is a large gear ring fixed with a spring plate near the kiln tail; some pinions below are engaged with it, jointly forming the drive gear. In normal operation, the main drive motor will transfer power to this gear device through a reducer to run a rotary kiln. The raw material usually enters the rotary kiln from the upper end and moves slowly to another end along with the chamber as it rotates. In this process, raw materials will be heated by high temperature and then decompose and produce chemical reactions so that their state finally changes. Under normal conditions, the heat source of indirect fired rotary kilns is supplied from the kiln burner outside the kiln. This kind of way protects the integrity of raw materials, while the heat source of the direct-fired rotary kiln is inside the kiln. Besides, the rotation speed and temperature of the cylinder are tightly controlled and changed according to different desired processes and material applications. After the calcination is completed, the clinker will be pre-cooled in the chamber and then be sent into the cooler for further cooling.

With the continuous progress of the cement industry, rotary kilns, as the core cement equipment of the cement production line, is developing towards a large scale. Compared with the traditional rotary kiln, its technology is more complex, and the requirements for rotary kiln design and accessories are higher. The rotary kiln refractory lining is a layer of refractory material installed inside the kiln cylinder, which plays a protective role in many aspects, and is an important part of cement rotary kiln.

To protect the shell of the kiln from the high temperatures of the feed and combustion gases, a brick lining is used. Refractories play a critical role in both the rotary kiln lining, and the lining of the high-volume static equipment areas that comprise a modern pre-calciner kiln system.

Refractories require an insulating coating or lining further helping its function of preventing heat from escaping the kiln. Some of the key features that this coating material must have are:

High adhering potential to the lining and bricks
Mouldable to various shapes and sizes to fill in the gaps and holes of the brick lining
Acts as a protective layer against corrosion from flames and molten substances
Provides thermal spalling
Improves surface resistance to erosions and voids.

Layers of Refractories

Refractory is a customisable part of the rotary kiln and can be designed to suit the requirement of the desired clinker and subsequently, the end product of the process, cement. It can be tailored with multiple layers to meet the demands of a given application.

A refractory mostly has two layers, the working layer and the insulating layer and the combined thickness of the two ranges from 4.5 inches to 12 inches. They are made with materials that can withstand the high temperature process that takes place in the cement manufacturing process.

Working layer is designed with durable materials designed to withstand the heat within the rotary kiln as it comes directly in contact with the materials and raw mix being processed. It also goes through constant abrasion as it comes in contact with the materials.

An insulating layer is required beneath the working layer of the refractory to prevent the heat from slipping out to the shell of the kiln. This would be both dangerous as well as would lead to loss of efficiency and productivity of the process. It would also lead to damage of the kiln shell.

Typically, the working layer and the insulating layer are made of the same material (ie. brick or castable), with varying chemistries. The working layer tends to be a higher density, stronger material that is more conductive. The insulating layer does not need these qualities, and tends to be softer, lighter, and less conductive, therefore more insulating. These two layers often vary in thicknesses, determined by the needs of the rotary kiln and what material is being processed. In some cases, such as when temperatures are low, or when efficiency is not a concern, a single working layer may be all that is needed.

In contrast, when insulation is extremely critical, an optional third layer of ceramic fibre backing may be used. This thin, but very efficient layer is like fibreglass insulation found in a house, but it is much more compressed. The decision to employ this layer comes with some responsibility. Should a crack in the refractory occur and go unnoticed, it is possible for the high heat inside the rotary kiln to reach this backing and burn it up. This would create a gap between the refractory and the shell of the rotary kiln, which would cause disastrous problems. Due to this potential of increased risk, this third layer is not always appropriate.

Refractory Materials

A refractory is made of inert inorganic solid materials like oxides, carbides, nitrides, and borides of aluminium, silicon, alkaline earth metals, and transition metals. The key requirements of the materials from which a refractory is built are to be stable at high temperatures and to retain their original physical shape when they are exposed to corrosive solid, liquid or gaseous materials. Out of all these materials, very few qualify to be used in industrial scale, because of their instability under normal atmospheric conditions or because of the rare availability and high cost.

“Cement manufacturing is an energy intensive process. Burning alkaline raw materials (reactive) combined with smaller constituents of metals and abrasive raw materials at very high temperature is a major challenge. Therefore, a good refractory that can withstand high temperatures while retaining required strength and that is resistant to chemical properties of the alkaline raw materials is crucial. Besides, chemical attacks from sulphates or chlorine from the kiln feed, fuel or alternative fuels there are other factors that need to be factored in,” says Prabhat Singh Parihar, Vice President Technical Head, Mangrol Plant, JK Cement.

The source of the raw materials can be natural or synthetic. The raw materials used for refractory manufacturing are mainly naturally occurring minerals like bauxite, magnesite, clay etc., which are mined and processed before being used for refractory manufacturing. Some synthetic materials like mullite (3Al2O3.2SiO2), fused alumina (Al2O3), silicon carbide (SiC), spinel (MgO.Al2O3) etc., are also being used widely in refractories for the cement industry.

Operating Condition for Refractories

According to a report – Refractories Selection for Cement Industry, August 2020 published by IN Chakraborty, Ace Calderys Limited, Nagpur, refractory selection is the most important step for the maximisation of its performance.

Refractories play a critical role in both the rotary kiln lining, and the lining of the high-volume static equipment
areas that comprise a modern pre-calciner kiln system.

The major deciding factors for refractory selection are the working environment where the refractory would be used. The working environment, in general, is defined by the following parameters:

Operating temperature
Chemical condition
Chemical nature of solid or liquid, i.e., acidic, or basic, in contact with the refractory
Characteristic of the gaseous environment
Thermal shock
Mechanical stress
Abrasion

Refractory selection is the most important step for the maximisation of its performance. The major deciding factor for refractory selection is the working or operating environment where the refractory would be used. The working environment, in general, is defined by the following parameters:

Identification of critical parameters for a given working environment is vital for refractory life maximisation at optimal cost. Once the critical operating parameters are identified, the refractory should be so selected that it can withstand the operating condition for the stipulated lifespan. In the context of the refractory life in the cement rotary kiln, the lining design as well as the quality of refractory installation play a very critical role.

As a function of the cement manufacturing process, a raw meal i.e., a mix of limestone, quartz, clay and some lateritic material is fed in the kiln. This operating condition in this kiln is not severe except for in the burning zone where temperature can go up to 1450oC and the liquid content of the feed material falls in the range of 25 per cent to 27 per cent

By the time the raw mix attains a temperature of 900oC, the limestone present in the raw material is decomposed and quartz undergoes polymorphic transformation and cement constituents like C2S and C3A start forming. None of these have an adverse effect on the refractory. As the temperature rises to 1400oC, the liquid phase forms. At the maximum operating temperature, approximately 1450oC, the liquid phase concentration is about 25 per cent. On cooling down the C3S and C4AF precipitate out from the melt. As the clinker cools down, the reactivity of the mass reduces, i.e., the refractory is not chemically affected. However, the cold clinker becomes abrasive and may cause erosions on the refractory.

This operating condition of the kiln is of moderate severity from the chemical reactions point of view. The temperature in the non-burning zone part of the kiln system is not high enough for a chemical reaction between the aluminous refractory and the lime bearing raw material of the clinker.

This situation, however, becomes severe when alternative fuels are used. It is their alkali and chlorine concentrations that are significantly high compared to the conventional fuels. The melting points of these alkali compounds are lower than the maximum operating temperature of the kiln, hence, they evaporate in the kiln and travel along with the flue gas towards the kiln inlet areas whereas the rest escape in the kiln system by combining with the clinker. This alkali bearing gas then gets deposited on the incoming raw meal at the corresponding feeding point of these alkali compounds. The alkali enriched raw meal travels back to the kiln and the process repeats.

Refractory failure inside the rotary kiln is indicated when the kiln shell becomes red hot because the refractory lining
has either been entirely lost or has become too thin.

The chloride compounds have a lower melting point than the sulphates. They have the ability to travel further back in the kiln system, compared to sulphur bearing compounds. Owing to this cycling process, the kiln environment becomes richer in alkalis as compared to their concentration in the raw meals. Owing to the self-enrichment phenomenon, raw meal chemistry does not indicate the true chemical environment of the kiln.

Properties of Refractories

Refractories are characterised by their chemical and physical properties and are used to correlate its behaviour in actual high-temperature application.

Apparent Porosity: Refractories contain pores; some of the pores are open and connected and some are closed. The total volume of a refractory body is the sum of the volume of the matter, volume of the open pores and the volume of closed pores. The apparent porosity of a refractory is expressed in percentage and is defined as a percentage of the volume of open pores against the total volume.

It is a very important property and influences the mechanical strength, corrosion resistance, and thermal conductivity of a refractory. Porosity and bulk density of a refractory are inversely related. The lower the apparent porosity, the more will be the bulk density, mechanical strength, thermal conductivity, and corrosion resistance of the body. Besides total pore volume, the pore sizes are also very important to influence the corrosion resistance and thermal conductivity of the refractory. The smaller the pore sizes, the better is the corrosion resistance and the lower is the thermal conductivity.

Permeability: It is the measure of flow of gases through pores within the refractory body, and it indicates the extent of pore linkage. Permeability of refractories gives an indication on how well the Refractory will stand up to molten slag, a melt or to a gas penetration.

“The apparent porosity or open porosity (oPo) is the volume of the open pores, into which a liquid can penetrate, as a percentage of the total volume of the refractory. This property is important when the refractory is in contact with molten charge. A low apparent porosity prevents molten material from penetrating into the refractory, it makes a materialto- material bond and develops a good and stable coating on refractory / bricks, which enhances its life and its resistance to corrosion,” says Pradeep Kumar Chouhan, General Manager – Quality Control & Environment, Udaipur Cement Works Limited.

“The permeability of refractories is a governing factor in the deterioration of linings by liquids and gases. The permeability of any refractory material is defined as the volume of the gas or air, which passes through a cubic centimetre of material under a pressure of 10 mmWG per seconds” he adds.

Bulk Densities: It is the mass of the material per unit volume including pores. For the same kind of refractory, the bulk density can vary. The higher is the bulk density, the lesser will be the porosity and normally more will be the mechanical strength.

Specific Gravity: All different refractory minerals have different densities. They can be identified by their specific gravities. The specific gravity of a refractory can be determined by making powder of the sample of a specific size and using a specific gravity bottle and a balance.

Refractories are subjected to extreme temperatures and conditions. This is also a test of their mechanical properties. Some of the key mechanical properties of a refractory are:Cold Crushing StrengthModulus RuptureModulus of ElasticityFractureAbrasion Resistance

Factors Affecting the Maintenance of Refractories

Among kiln operators, refractory failure is considered the most critical upset in a kiln operation. Refractory failure inside the rotary kiln is indicated when the kiln shell becomes red hot because the refractory lining has either been entirely lost or has become so thin in an area that the kiln shell becomes overheated.

In most instances, however, damage can be avoided if the kiln is shut down for lining replacement as soon as the shell starts to show a large red spot.

Replacement of the kiln lining, especially in the burning zone, is unfortunately a frequent necessity, exerting a large strain on the operating budget and on production schedules.

Many plants have found that refractory life is often directly proportional to the number of kiln shutdowns that were experienced while the refractory was in the kiln. The more shutdowns and kilns stop, the shorter the life. The danger of damaging the refractory is directly related to the rate of cooling of the kiln, the danger being the greatest when cooling is too rapid.

When processing a highly abrasive material, a brick refractory is advisable.

The first step in preventing this situation is to eliminate shutdowns by operating the kiln more efficiently on a continuous basis. The second step is to make sure that cooling is slow and uniform when the kiln is shut down. Cooling time should be a minimum of 8 hours or longer. Placing a large guillotine damper to seal the kiln exit (back-end) helps to conserve heat inside the kiln and retards cooling during a shutdown. Another method of ensuring slow cooling of the refractory in the kiln is to shut the draft fan immediately when the fire is taken out of the kiln.

The primary air fan should be left running only for such a time as needed to protect the burner pipe from heat during the early period of kiln cooling.

As rapid cooling can cause damage to the refractory, so can rapidly heating it. Heating up the refractory quickly can cause thermal deterioration of the brick. Governed partly by the concept of thermal conductivity of the refractory, the kiln shell expansion takes place slower than the bricks. Because of this, the heating process should be for a minimum of 16 hours and should be gradually built up.

Another important factor to be considered for the longevity of the refractory life is to avoid overheating it. This can be ensured by constant monitoring of the kiln temperature and taking corrective action if the temperature rises beyond the threshold.

Having the refractory installed uniformly and in a shapely manner as per the kiln and end product requirement prevents its wear and tear when exposed to high temperature and erosive conditions. Kiln managers should also select the right type of refractories for each location of the kiln which is easier said than done.

Building the right refractory is a key process in the cement manufacturing process as this protective layer of the kiln withstands high temperature and handles the process of converting limestone to clinker and its cooling. Having the right shape, size and composition of refractory in the manufacturing unit increases the overall productivity and efficiency of the cement manufacturing process, thus, also increasing the profitability of the organisation at large. Paying keen attention to its installation and maintenance is important and must be done on a regular basis under expert guidance.

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Refractory demands in our kiln have changed

Published

3 days ago

February 20, 2026

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Radha Singh, Senior Manager (P&Q), Shree Digvijay Cement, points out why performance, predictability and life-cycle value now matter more than routine replacement in cement kilns.

As Indian cement plants push for higher throughput, increased alternative fuel usage and tighter shutdown cycles, refractory performance in kilns and pyro-processing systems is under growing pressure. In this interview, Radha Singh, Senior Manager (P&Q), Shree Digvijay Cement, shares how refractory demands have evolved on the ground and how smarter digital monitoring is improving kiln stability, uptime and clinker quality.

How have refractory demands changed in your kiln and pyro-processing line over the last five years?
Over the last five years, refractory demands in our kiln and pyro line have changed. Earlier, the focus was mostly on standard grades and routine shutdown-based replacement. But now, because of higher production loads, more alternative fuels and raw materials (AFR) usage and greater temperature variation, the expectation from refractory has increased.
In our own case, the current kiln refractory has already completed around 1.5 years, which itself shows how much more we now rely on materials that can handle thermal shock, alkali attack and coating fluctuations. We have moved towards more stable, high-performance linings so that we don’t have to enter the kiln frequently for repairs.
Overall, the shift has been from just ‘installation and run’ to selecting refractories that give longer life, better coating behaviour and more predictable performance under tougher operating conditions.

What are the biggest refractory challenges in the preheater, calciner and cooler zones?
• Preheater: Coating instability, chloride/sulphur cycles and brick erosion.
• Calciner: AFR firing, thermal shock and alkali infiltration.
• Cooler: Severe abrasion, red-river formation and mechanical stress on linings.
Overall, the biggest challenge is maintaining lining stability under highly variable operating conditions.

How do you evaluate and select refractory partners for long-term performance?
In real plant conditions, we don’t select a refractory partner just by looking at price. First, we see their past performance in similar kilns and whether their material has actually survived our operating conditions. We also check how strong their technical support is during shutdowns, because installation quality matters as much as the material itself.
Another key point is how quickly they respond during breakdowns or hot spots. A good partner should be available on short notice. We also look at their failure analysis capability, whether they can explain why a lining failed and suggest improvements.
On top of this, we review the life they delivered in the last few campaigns, their supply reliability and their willingness to offer plant-specific custom solutions instead of generic grades. Only a partner who supports us throughout the life cycle, which includes selection, installation, monitoring and post-failure analysis, fits our long-term requirement.

Can you share a recent example where better refractory selection improved uptime or clinker quality?
Recently, we upgraded to a high-abrasion basic brick at the kiln outlet. Earlier we had frequent chipping and coating loss. With the new lining, thermal stability improved and the coating became much more stable. As a result, our shutdown interval increased and clinker quality remained more consistent. It had a direct impact on our uptime.

How is increased AFR use affecting refractory behaviour?
Increased AFR use is definitely putting more stress on the refractory. The biggest issue we see daily is the rise in chlorine, alkalis and volatiles, which directly attack the lining, especially in the calciner and kiln inlet. AFR firing is also not as stable as conventional fuel, so we face frequent temperature fluctuations, which cause more thermal shock and small cracks in the lining.
Another real problem is coating instability. Some days the coating builds too fast, other days it suddenly drops, and both conditions impact refractory life. We also notice more dust circulation and buildup inside the calciner whenever the AFR mix changes, which again increases erosion.
Because of these practical issues, we have started relying more on alkali-resistant, low-porosity and better thermal shock–resistant materials to handle the additional stress coming from AFR.

What role does digital monitoring or thermal profiling play in your refractory strategy?
Digital tools like kiln shell scanners, IR imaging and thermal profiling help us detect weakening areas much earlier. This reduces unplanned shutdowns, helps identify hotspots accurately and allows us to replace only the critical sections. Overall, our maintenance has shifted from reactive to predictive, improving lining life significantly.

How do you balance cost, durability and installation speed during refractory shutdowns?
We focus on three points:
• Material quality that suits our thermal profile and chemistry.
• Installation speed, in fast turnarounds, we prefer monolithic.
• Life-cycle cost—the cheapest material is not the most economical. We look at durability, future downtime and total cost of ownership.
This balance ensures reliable performance without unnecessary expenditure.

What refractory or pyro-processing innovations could transform Indian cement operations?
Some promising developments include:
• High-performance, low-porosity and nano-bonded refractories
• Precast modular linings to drastically reduce shutdown time
• AI-driven kiln thermal analytics
• Advanced coating management solutions
• More AFR-compatible refractory mixes

These innovations can significantly improve kiln stability, efficiency and maintenance planning across the industry.

Concrete

Digital supply chain visibility is critical

Published

3 days ago

February 20, 2026

admin

MSR Kali Prasad, Chief Digital and Information Officer, Shree Cement, discusses how data, discipline and scale are turning Industry 4.0 into everyday business reality.

Over the past five years, digitalisation in Indian cement manufacturing has moved decisively beyond experimentation. Today, it is a strategic lever for cost control, operational resilience and sustainability. In this interview, MSR Kali Prasad, Chief Digital and Information Officer, Shree Cement, explains how integrated digital foundations, advanced analytics and real-time visibility are helping deliver measurable business outcomes.

How has digitalisation moved from pilot projects to core strategy in Indian cement manufacturing over the past five years?
Digitalisation in Indian cement has evolved from isolated pilot initiatives into a core business strategy because outcomes are now measurable, repeatable and scalable. The key shift has been the move away from standalone solutions toward an integrated digital foundation built on standardised processes, governed data and enterprise platforms that can be deployed consistently across plants and functions.
At Shree Cement, this transition has been very pragmatic. The early phase focused on visibility through dashboards, reporting, and digitisation of critical workflows. Over time, this has progressed into enterprise-level analytics and decision support across manufacturing and the supply chain,
with clear outcomes in cost optimisation, margin protection and revenue improvement through enhanced customer experience.
Equally important, digital is no longer the responsibility of a single function. It is embedded into day-to-day operations across planning, production, maintenance, despatch and customer servicing, supported by enterprise systems, Industrial Internet of Things (IIoT) data platforms, and a structured approach to change management.

Which digital interventions are delivering the highest ROI across mining, production and logistics today?
In a capital- and cost-intensive sector like cement, the highest returns come from digital interventions that directly reduce unit costs or unlock latent capacity without significant capex.
Supply chain and planning (advanced analytics): Tools for demand forecasting, S&OP, network optimisation and scheduling deliver strong returns by lowering logistics costs, improving service levels, and aligning production with demand in a fragmented and regionally diverse market.
Mining (fleet and productivity analytics): Data-led mine planning, fleet analytics, despatch discipline, and idle-time reduction improve fuel efficiency and equipment utilisation, generating meaningful savings in a cost-heavy operation.
Manufacturing (APC and process analytics): Advanced Process Control, mill optimisation, and variability reduction improve thermal and electrical efficiency, stabilise quality and reduce rework and unplanned stoppages.
Customer experience and revenue enablement (digital platforms): Dealer and retailer apps, order visibility and digitally enabled technical services improve ease of doing business and responsiveness. We are also empowering channel partners with transparent, real-time information on schemes, including eligibility, utilisation status and actionable recommendations, which improves channel satisfaction and market execution while supporting revenue growth.
Overall, while Artificial Intelligence (AI) and IIoT are powerful enablers, it is advanced analytics anchored in strong processes that typically delivers the fastest and most reliable ROI.

How is real-time data helping plants shift from reactive maintenance to predictive and prescriptive operations?
Real-time and near real-time data is driving a more proactive and disciplined maintenance culture, beginning with visibility and progressively moving toward prediction and prescription.
At Shree Cement, we have implemented a robust SAP Plant Maintenance framework to standardise maintenance workflows. This is complemented by IIoT-driven condition monitoring, ensuring consistent capture of equipment health indicators such as vibration, temperature, load, operating patterns and alarms.
Real-time visibility enables early detection of abnormal conditions, allowing teams to intervene before failures occur. As data quality improves and failure histories become structured, predictive models can anticipate likely failure modes and recommend timely interventions, improving MTBF and reducing downtime. Over time, these insights will evolve into prescriptive actions, including spares readiness, maintenance scheduling, and operating parameter adjustments, enabling reliability optimisation with minimal disruption.
A critical success factor is adoption. Predictive insights deliver value only when they are embedded into daily workflows, roles and accountability structures. Without this, they remain insights without action.

In a cost-sensitive market like India, how do cement companies balance digital investment with price competitiveness?
In India’s intensely competitive cement market, digital investments must be tightly linked to tangible business outcomes, particularly cost reduction, service improvement, and faster decision-making.
This balance is achieved by prioritising high-impact use cases such as planning efficiency, logistics optimisation, asset reliability, and process stability, all of which typically deliver quick payback. Equally important is building scalable and governed digital foundations that reduce the marginal cost of rolling out new use cases across plants.
Digitally enabled order management, live despatch visibility, and channel partner platforms also improve customer centricity while controlling cost-to-serve, allowing service levels to improve without proportionate increases in headcount or overheads.
In essence, the most effective digital investments do not add cost. They protect margins by reducing variability, improving planning accuracy, and strengthening execution discipline.

How is digitalisation enabling measurable reductions in energy consumption, emissions, and overall carbon footprint?
Digitalisation plays a pivotal role in improving energy efficiency, reducing emissions and lowering overall carbon intensity.
Real-time monitoring and analytics enable near real-time tracking of energy consumption and critical operating parameters, allowing inefficiencies to be identified quickly and corrective actions to be implemented. Centralised data consolidation across plants enables benchmarking, accelerates best-practice adoption, and drives consistent improvements in energy performance.
Improved asset reliability through predictive maintenance reduces unplanned downtime and process instability, directly lowering energy losses. Digital platforms also support more effective planning and control of renewable energy sources and waste heat recovery systems, reducing dependence on fossil fuels.
Most importantly, digitalisation enables sustainability progress to be tracked with greater accuracy and consistency, supporting long-term ESG commitments.

What role does digital supply chain visibility play in managing demand volatility and regional market dynamics in India?
Digital supply chain visibility is critical in India, where demand is highly regional, seasonality is pronounced, and logistics constraints can shift rapidly.
At Shree Cement, planning operates across multiple horizons. Annual planning focuses on capacity, network footprint and medium-term demand. Monthly S&OP aligns demand, production and logistics, while daily scheduling drives execution-level decisions on despatch, sourcing and prioritisation.
As digital maturity increases, this structure is being augmented by central command-and-control capabilities that manage exceptions such as plant constraints, demand spikes, route disruptions and order prioritisation. Planning is also shifting from aggregated averages to granular, cost-to-serve and exception-based decision-making, improving responsiveness, lowering logistics costs and strengthening service reliability.

How prepared is the current workforce for Industry 4.0, and what reskilling strategies are proving most effective?
Workforce preparedness for Industry 4.0 is improving, though the primary challenge lies in scaling capabilities consistently across diverse roles.
The most effective approach is to define capability requirements by role and tailor enablement accordingly. Senior leadership focuses on digital literacy for governance, investment prioritisation, and value tracking. Middle management is enabled to use analytics for execution discipline and adoption. Frontline sales and service teams benefit from
mobile-first tools and KPI-driven workflows, while shop-floor and plant teams focus on data-driven operations, APC usage, maintenance discipline, safety and quality routines.
Personalised, role-based learning paths, supported by on-ground champions and a clear articulation of practical benefits, drive adoption far more effectively than generic training programmes.

Which emerging digital technologies will fundamentally reshape cement manufacturing in the next decade?
AI and GenAI are expected to have the most significant impact, particularly when combined with connected operations and disciplined processes.
Key technologies likely to reshape the sector include GenAI and agentic AI for faster root-cause analysis, knowledge access, and standardisation of best practices; industrial foundation models that learn patterns across large sensor datasets; digital twins that allow simulation of process changes before implementation; and increasingly autonomous control systems that integrate sensors, AI, and APC to maintain stability with minimal manual intervention.
Over time, this will enable more centralised monitoring and management of plant operations, supported by strong processes, training and capability-building.

Concrete

Redefining Efficiency with Digitalisation

Published

3 days ago

February 20, 2026

admin

Professor Procyon Mukherjee discusses how as the cement industry accelerates its shift towards digitalisation, data-driven technologies are becoming the mainstay of sustainability and control across the value chain.

The cement industry, long perceived as traditional and resistant to change, is undergoing a profound transformation driven by digital technologies. As global infrastructure demand grows alongside increasing pressure to decarbonise and improve productivity, cement manufacturers are adopting data-centric tools to enhance performance across the value chain. Nowhere is this shift more impactful than in grinding, which is the energy-intensive final stage of cement production, and in the materials that make grinding more efficient: grinding media and grinding aids.

The imperative for digitalisation
Cement production accounts for roughly 7 per cent to 8 per cent of global CO2 emissions, largely due to the energy intensity of clinker production and grinding processes. Digital solutions, such as AI-driven process controls and digital twins, are helping plants improve stability, cut fuel use and reduce emissions while maintaining consistent product quality. In one deployment alongside ABB’s process controls at a Heidelberg plant in Czechia, AI tools cut fuel use by 4 per cent and emissions by 2 per cent, while also improving operational stability.
Digitalisation in cement manufacturing encompasses a suite of technologies, broadly termed as Industrial Internet of Things (IIoT), AI and machine learning, predictive analytics, cloud-based platforms, advanced process control and digital twins, each playing a role in optimising various stages of production from quarrying to despatch.

Grinding: The crucible of efficiency and cost
Of all the stages in cement production, grinding is among the most energy-intensive, historically consuming large amounts of electricity and representing a significant portion of plant operating costs. As a result, optimising grinding operations has become central to digital transformation strategies.
Modern digital systems are transforming grinding mills from mechanical workhorses into intelligent, interconnected assets. Sensors throughout the mill measure parameters such as mill load, vibration, mill speed, particle size distribution, and power consumption. This real-time data, fed into machine learning and advanced process control (APC) systems, can dynamically adjust operating conditions to maintain optimal throughput and energy usage.
For example, advanced grinding systems now predict inefficient conditions, such as impending mill overload, by continuously analysing acoustic and vibration signatures. The system can then proactively adjust clinker feed rates and grinding media distribution to sustain optimal conditions, reducing energy consumption and improving consistency.

Digital twins: Seeing grinding in the virtual world
One of the most transformative digital tools applied in cement grinding is the digital twin, which a real-time virtual replica of physical equipment and processes. By integrating sensor data and
process models, digital twins enable engineers to simulate process variations and run ‘what-if’
scenarios without disrupting actual production. These simulations support decisions on variables such as grinding media charge, mill speed and classifier settings, allowing optimisation of energy use and product fineness.
Digital twins have been used to optimise kilns and grinding circuits in plants worldwide, reducing unplanned downtime and allowing predictive maintenance to extend the life of expensive grinding assets.

Grinding media and grinding aids in a digital era
While digital technologies improve control and prediction, materials science innovations in grinding media and grinding aids have become equally crucial for achieving performance gains.
Grinding media, which comprise the balls or cylinders inside mills, directly influence the efficiency of clinker comminution. Traditionally composed of high-chrome cast iron or forged steel, grinding media account for nearly a quarter of global grinding media consumption by application, with efficiency improvements translating directly to lower energy intensity.
Recent advancements include ceramic and hybrid media that combine hardness and toughness to reduce wear and energy losses. For example, manufacturers such as Sanxin New Materials in China and Tosoh Corporation in Japan have developed sub-nano and zirconia media with exceptional wear resistance. Other innovations include smart media embedded with sensors to monitor wear, temperature, and impact forces in real time, enabling predictive maintenance and optimal media replacement scheduling. These digitally-enabled media solutions can increase grinding efficiency by as much as 15 per cent.
Complementing grinding media are grinding aids, which are chemical additives that improve mill throughput and reduce energy consumption by altering the surface properties of particles, trapping air, and preventing re-agglomeration. Technology leaders like SIKA AG and GCP Applied Technologies have invested in tailored grinding aids compatible with AI-driven dosing platforms that automatically adjust additive concentrations based on real-time mill conditions. Trials in South America reported throughput improvements nearing 19 per cent when integrating such digital assistive dosing with process control systems.
The integration of grinding media data and digital dosing of grinding aids moves the mill closer to a self-optimising system, where AI not only predicts media wear or energy losses but prescribes optimal interventions through automated dosing and operational adjustments.

Global case studies in digital adoption
Several cement companies around the world exemplify digital transformation in practice.
Heidelberg Materials has deployed digital twin technologies across global plants, achieving up to 15 per cent increases in production efficiency and 20 per cent reductions in energy consumption by leveraging real-time analytics and predictive algorithms.
Holcim’s Siggenthal plant in Switzerland piloted AI controllers that autonomously adjusted kiln operations, boosting throughput while reducing specific energy consumption and emissions.
Cemex, through its AI and predictive maintenance initiatives, improved kiln availability and reduced maintenance costs by predicting failures before they occurred. Global efforts also include AI process optimisation initiatives to reduce energy consumption and environmental impact.

Challenges and the road ahead
Despite these advances, digitalisation in cement grinding faces challenges. Legacy equipment may lack sensor readiness, requiring retrofits and edge-cloud connectivity upgrades. Data governance and integration across plants and systems remains a barrier for many mid-tier producers. Yet, digital transformation statistics show momentum: more than half of cement companies have implemented IoT sensors for equipment monitoring, and digital twin adoption is growing rapidly as part of broader Industry 4.0 strategies.
Furthermore, as digital systems mature, they increasingly support sustainability goals: reduced energy use, optimised media consumption and lower greenhouse gas emissions. By embedding intelligence into grinding circuits and material inputs like grinding aids, cement manufacturers can strike a balance between efficiency and environmental stewardship.
Conclusion
Digitalisation is not merely an add-on to cement manufacturing. It is reshaping the competitive and sustainability landscape of an industry often perceived as inertia-bound. With grinding representing a nexus of energy intensity and cost, digital technologies from sensor networks and predictive analytics to digital twins offer new levers of control. When paired with innovations in grinding media and grinding aids, particularly those with embedded digital capabilities, plants can achieve unprecedented gains in efficiency, predictability and performance.
For global cement producers aiming to reduce costs and carbon footprints simultaneously, the future belongs to those who harness digital intelligence not just to monitor operations, but to optimise and evolve them continuously.

About the author:
Professor Procyon Mukherjee, ex-CPO Lafarge-Holcim India, ex-President Hindalco, ex-VP Supply Chain Novelis Europe, has been an industry leader in logistics, procurement, operations and supply chain management. His career spans 38 years starting from Philips, Alcan Inc (Indian Aluminum Company), Hindalco, Novelis and Holcim. He authored the book, ‘The Search for Value in Supply Chains’. He serves now as Visiting Professor in SP Jain Global, SIOM and as the Adjunct Professor at SBUP. He advises leading Global Firms including Consulting firms on SCM and Industrial Leadership and is a subject matter expert in aluminum and cement. An Alumnus of IIM Calcutta and Jadavpur University, he has completed the LH Senior Leadership Programme at IVEY Academy at Western University, Canada.