Technology
Finer the fly ash or slag, more value it commands
Published
7 years agoon
By
admin
– Bhalchandra Shrikhande, a freelance consultant, speaks on split grinding cement units.
What is your opinion on the ease-of-doing business?
There is lot of hype on "ease-of-doing business", but very little has happened in reality at the ground level. The percolation of progressive policies framed at the macro level to promote fast growth in business and manufacturing are yet to make a difference at the working level. The reasons of this are many.
A few among them are lack of clarity in executing the new policies, non-removal of some old and redundant rules and regulations, insistence to go by the letter, and not the spirit of the rules/regulations, sense of apathy among the government officers due to the fact that doing nothing attracts no penalty, but doing something, albeit with good intention, and not getting the desired result does attract enquiry, audits and penalties. There is no compulsion on the decision-making authorities to take appropriate decisions within a reasonable time frame, and to avoid duplicity of efforts in seeking approvals. Let us all hope that sooner or later ease-of-doing business becomes a reality.
What is your assessment of a business model of split grinding cement unit? What are the critical success parameters?
In the beginning, let us look at the parameters of success of a standalone split grinding cement unit. If we evaluate the parameters along with an integrated cement plant, the picture will not be clear. The success of a split grinding cement unit should be measured by the capacity utilisation and the EBIDTA margin of the unit. While working out the manufacturing cost; one should be judicious enough to consider the market prices of all inputs. Special attention needs to be given to the transfer price of clinker from the integrated plant to the grinding unit. It should be close to the real price of clinker in the market. The cornerstones of successful business grinding unit are:
Volume addition is an essential factor in achieving a reasonably good standalone EBIDTA in split grinding cement units. This depends on the percentage addition of mineral components (MiC) like fly ash or slag at the split unit. It is thus very beneficial to have the location of split unit near the source of MiC, i.e. power plant or steel plant. Such a location also helps to get power generated by the power/steel plant at the split unit reliably and cheaply.
Nearness to market having high potential of growth is another important factor concerning location. This results in the "last mile connectivity" to the end consumer and substantial logistics cost saving as well.
Can more of bulk cement (loose cement despatched in bulkers) be a better option for split grinding cement unit along with a smaller proportion of bagged cement?
In today’s world, the operating strategies must keep the customer at the focal point. Customers have different requirements at different times. E.g.: when a construction project is nearing completion, the customer may need more of masonry cement or readymade dry plaster or blended cement of lower grade for flooring/ tiling applications, that too in bags. When concreting job is in progress, he will need cement (OPC) of higher grades in bulkers. Therefore, the grinding unit must be able to cater to all the requirements of the customers. No split grinding plant can survive on bulk cement supply alone. Generally bulk cement goes to large infrastructure and residential projects, and RMC plants. These locations have dedicated batching plants at site. Small retail end users however prefer cement in bags. For packing the cement of different grades in bags, you need to have a packing plant with more number of cement storage silos. For supply of cement in bulk, you need to have arrangements for accommodating different types of bulkers directly under the silos and loading arrangements. Therefore, in order to be successful, you will need all the flexibility in the grinding unit.
The last mile connectivity also eliminates need to have warehouses, reduces double handling and transportation to the point of consumption, on-time delivery, and better quality perception in the mind of the customers.
Logistic seems to be a big challenge for split grinding plants, please comment. Inward and outward movement of materials being critical, how important it becomes to monitor and manage logistics?
Yes, logistics is a considerable challenge and an important cost component especially when you are sourcing clinker as a vendor. Incoming material logistics is essentially a bulk movement either by a rail or a ship. Clinker is moved by railway wagons and directly unloaded by wagon tippler inside the plant. The outgoing movement of cement by rail is desirable but not always feasible. You however need to have good road connectivity for cement evacuation. Export-oriented cement units are required to be located at ports near sea to facilitate direct loading of ships/barges.
Should split grinding cement units be automated by using modern technology in a better way than normal cement plants?
As a corollary to my earlier statement, I would add that to meet challenging customer requirements, like quick delivery and better quality assurance, usage of modern technology is the need of the hour. IoT (Internet of Things) has been successfully used by some cement grinding units for despatch of cement. Today transporters are given smart cards where the entire data of sales order is stored. This results in faster turnaround time of a truck/trailer/bulker. Ready availability of different grades of cement simultaneously meets diverse customer needs. Flexible plant design can operate fast only if equipped with good automation. At short notice you have to shift from one to the other product, different quantities, and different packaging and this can be managed by IoT. Having weighbridges under the loading spouts, auto loading spouts, automatic bag placers, auto pelletizers and loaders, CCTV monitoring of operations etc. help in managing complex tasks easily. Dependence on labour is not only unreliable and costly, but can also lead to delays.
Throw some light on the power scenario of such grinding unit?
For a given split cement grinding unit, power requirement is generally of the order of 8 to 12 MW depending on the size of the unit. In majority of cases power is drawn from the adjoining thermal power plant. If there is steel plant, power can be tapped from the steel plant CPP. In most of the cases it is B2B type of transaction. The practical way is to route it through HT cables. Grid power is unreliable, but given the nature of the grinding unit, this can be managed. However, installing a captive power plant, which is based on multiple DG sets, is ruled out because of high cost. My suggestion is rules should be simplified to draw power from wherever it is convenient and simple.
Most of the split grinding plants are located close to sea or river for easy water way transportation is it correct?
Considering that a very small quantity of cement today is getting exported, in the present situation location near to a port hardly matters. But waterways transport by rivers is an interesting option, which needs to be explored. Water transport eases load on the roads, reduces pollution and is more cost effective.
Is it possible for a grinding plant to invest money in improving the quality of blended materials like fly ash or slag? What has been the practice?
It is very much essential to pre-process the fly ash or slag. Quality of fly ash differs in properties with its particle size distribution. Generally for processing of fly ash, mechanical air classifiers are deployed. Finer the fly ash or slag, more reactive it is, and more value it commands. Superfine fly ash/slag can be directly added to concrete to produce high-performance concrete (HPC). Medium grade fly ash/ground granulated blast-furnace slag (GGBS) can be used to manufacture common grades of concrete. Coarse fly ash can be used in the spilt grinding unit to be co-ground with clinker. In case of blast furnace slag, the problem is getting slag lumps that need to be separated. The extent of addition of fly ash/slag component in cement depends on its quality. With better quality of fly ash or slag, more proportion can be added in cement (within what is prescribed by Bureau of Indian Standards (BIS) and the profitability of the grinding unit will be better.
Do you suggest any better tax structure to make grinding units viable?
Today cement attracts GST at 28 per cent, which is in the highest bracket. Being a basic commodity of construction and infrastructure, the tax component is certainly on the higher side. If the overall industry gets a relief of lower tax rate, then the grinding units also will get the benefit.
Bhalchandra Shrikhande graduated from IIT, Bombay
in Chemical Engineering, and joined ACC Ltd in 1980. After working in ACC for 31 years, he then joined the Indiabulls (now, Rattan India) Group as President – Operations in 2011. At present, Shrikhande is working as a freelance consultant. The businesses in which he has worked are cement and ready-mix concrete.
The functional areas in which he has worked are R&D, process engineering and development, production, strategy/business planning, project execution and management, project engineering and design, management audits, consultancy assignments, organisational development and training.
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Concrete
Redefining Efficiency with Digitalisation
Published
2 weeks agoon
February 20, 2026By
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.
Concrete
Digital Pathways for Sustainable Manufacturing
Published
2 weeks agoon
February 20, 2026By
admin
Dr Y Chandri Naidu, Chief Technology Officer, Nextcem Consulting highlights how digital technologies are enabling Indian cement plants to improve efficiency, reduce emissions, and transition toward sustainable, low-carbon manufacturing.
Cement manufacturing is inherently resource- and energy-intensive due to high-temperature clinkerisation and extensive material handling and grinding operations. In India, where cement demand continues to grow in line with infrastructure development, producers must balance capacity expansion with sustainability commitments. Energy costs constitute a major share of operating expenditure, while process-related carbon dioxide emissions from limestone calcination remain unavoidable.
Traditional optimisation approaches, which are largely dependent on operator experience, static control logic and offline laboratory analysis, have reached their practical limits. This is especially evident when higher levels of alternative fuel and raw materials (AFR) are introduced or when raw material variability increases.
Digital technologies provide a systematic pathway to manage this complexity by enabling
real-time monitoring, predictive optimisation and integrated decision-making across cement manufacturing operations.
Digital cement manufacturing is enabled through a layered architecture integrating operational technology (OT) and information technology (IT). At the base are plant instrumentation, analysers, and automation systems, which generate continuous process data. This data is contextualised and analysed using advanced analytics and AI platforms, enabling predictive and prescriptive insights for operators and management.
Digital optimisation of energy efficiency
- Thermal energy optimisation
The kiln and calciner system accounts for approximately 60 per cent to 65 per cent of total energy consumption in an integrated cement plant. Digital optimisation focuses on reducing specific thermal energy consumption (STEC) while maintaining clinker quality and operational stability.
Advanced Process Control (APC) stabilises critical parameters such as burning zone temperature, oxygen concentration, kiln feed rate and calciner residence time. By minimising process variability, APC reduces the need for conservative over-firing. Artificial intelligence further enhances optimisation by learning nonlinear relationships between raw mix chemistry, AFR characteristics, flame dynamics and heat consumption.
Digital twins of kiln systems allow engineers to simulate operational scenarios such as increased AFR substitution, altered burner momentum or changes in raw mix burnability without operational risk. Indian cement plants adopting these solutions typically report STEC reductions in the range of 2 per cent to 5 per cent. - Electrical energy optimisation
Electrical energy consumption in cement plants is dominated by grinding systems, fans and material transport equipment. Machine learning–based optimisation continuously adjusts mill parameters such as separator speed, grinding pressure and feed rate to minimise specific power consumption while maintaining product fineness.
Predictive maintenance analytics identify inefficiencies caused by wear, fouling or imbalance in fans and motors. Plants implementing plant-wide electrical energy optimisation typically achieve
3 per cent to 7 per cent reduction in specific power consumption, contributing to both cost savings and indirect CO2 reduction.
Digital enablement of AFR
AFR challenges in the Indian context: Indian cement plants increasingly utilise biomass, refuse-derived fuel (RDF), plastic waste and industrial by-products. However, variability in calorific value, moisture, particle size, chlorine and sulphur content introduces combustion instability, build-up formation and emission risks.
Digital AFR management: Digital platforms integrate real-time AFR quality data from online analysers with historical kiln performance data. Machine learning models predict combustion behaviour, flame stability and emission trends for different AFR combinations. Based on these predictions, fuel feed distribution, primary and secondary air ratios, and burner momentum are dynamically adjusted to ensure stable kiln operation. Digitally enabled AFR management in cement plants will result in increased thermal substitution rates by 5-15 percentage points, reduced fossil fuel dependency, and improved kiln stability.
Digital resource and raw material optimisation
Raw mix control: Raw material variability directly affects kiln operation and clinker quality. AI-driven raw mix optimisation systems continuously adjust feed proportions to maintain target chemical parameters such as Lime Saturation Factor (LSF), Silica Modulus (SM), and Alumina Modulus (AM). This reduces corrective material usage and improves kiln thermal efficiency.
Clinker factor reduction: Reducing clinker factor through supplementary cementitious materials (SCMs) such as fly ash, slag and calcined clay is a key decarbonisation lever. Digital models simulate blended cement performance, enabling optimisation of SCM proportions while maintaining strength and durability requirements.
Challenges and strategies for digital adoption
Key challenges in Indian cement plants include data quality limitations due to legacy instrumentation, resistance to algorithm-based decision-making, integration complexity across multiple OEM systems, and site-specific variability in raw materials and fuels.
Successful digital transformation requires strengthening the data foundation, prioritising high-impact use cases such as kiln APC and energy optimisation, adopting a human-in-the-loop approach, and deploying modular, scalable digital platforms with cybersecurity by design.
Future Outlook
Future digital cement plants will evolve toward autonomous optimisation, real-time carbon intensity tracking, and integration with emerging decarbonisation technologies such as carbon capture, utilisation and storage (CCUS). Digital platforms will also support ESG reporting and regulatory compliance.
Digital pathways offer a practical and scalable solution for sustainable cement manufacturing in India. By optimising energy consumption, enabling higher AFR substitution and improving resource efficiency, digital technologies deliver measurable environmental and economic benefits. With appropriate data infrastructure, organisational alignment and phased implementation, digital transformation will remain central to the Indian cement industry’s low-carbon transition.
About the author:
Dr Y Chandri Naidu is a cement industry professional with 30+ years of experience in process optimisation, quality control and quality assistance, energy conservation and sustainable manufacturing, across leading organisations including NCB, Ramco, Prism, Ultratech, HIL, NCL and Vedanta. He is known for guiding teams, developing innovative plant solutions and promoting environmentally responsible cement production. He is also passionate about mentoring professionals and advancing durable, resource efficient technologies for future of construction materials.

Concrete
Turning Downtime into Actionable Intelligence
Published
2 weeks agoon
February 19, 2026By
admin
Stoppage Insights instantly identifies root causes and maps their full operational impact.
In cement, mining and minerals processing operations, every unplanned stoppage equals lost production and reduced profitability. Yet identifying what caused a stoppage remains frustratingly complex. A single motor failure can trigger cascading interlocks and alarm floods, burying the root cause under layers of secondary events. Operators and maintenance teams waste valuable time tracing event chains when they should be solving problems. Until now.
Our latest innovation to our ECS Process Control Solution(1) eliminates this complexity. Stoppage Insights, available with the combined updates to our ECS/ControlCenter™ (ECS) software and ACESYS programming library, transforms stoppage events into clear, actionable intelligence. The system automatically identifies the root cause of every stoppage – whether triggered by alarms, interlocks, or operator actions – and maps all affected equipment. Operators can click any stopped motor’s faceplate to view what caused the shutdown instantly. The Stoppage UI provides a complete record of all stoppages with drill-down capabilities, replacing manual investigation with immediate answers.
Understanding root cause in Stoppage Insights
In Stoppage Insights, ‘root cause’ refers to the first alarm, interlock, or operator action detected by the control system. While this may not reveal the underlying mechanical, electrical or process failure that a maintenance team may later discover, it provides an actionable starting point for rapid troubleshooting and response. And this is where Stoppage Insights steps ahead of traditional first-out alarm systems (ISA 18.2). In this older type of system, the first alarm is identified in a group. This is useful, but limited, as it doesn’t show the complete cascade of events, distinguish between operator-initiated and alarm-triggered stoppages, or map downstream impacts. In contrast, Stoppage Insights provides complete transparency:
- Comprehensive capture: Records both regular operator stops and alarm-triggered shutdowns.
- Complete impact visibility: Maps all affected equipment automatically.
- Contextual clarity: Eliminates manual tracing through alarm floods, saving critical response time.
David Campain, Global Product Manager for Process Control Systems, says, “Stoppage Insights takes fault analysis to the next level. Operators and maintenance engineers no longer need to trace complex event chains. They see the root cause clearly and can respond quickly.”
Driving results
1.Driving results for operations teams
Stoppage Insights maximises clarity to minimise downtime, enabling operators to:
• Rapidly identify root causes to shorten recovery time.
• View initiating events and all affected units in one intuitive interface.
• Access complete records of both planned and unplanned stoppages
- Driving results for maintenance and reliability teams
Stoppage Insights helps prioritise work based on evidence, not guesswork:
• Access structured stoppage data for reliability programmes.
• Replace manual logging with automated, exportable records for CMMS, ERP or MES.(2)
• Identify recurring issues and target preventive maintenance effectively.
A future-proof and cybersecure foundation
Our Stoppage Insights feature is built on the latest (version 9) update to our ACESYS advanced programming library. This industry-leading solution lies at the heart of the ECS process control system. Its structured approach enables fast engineering and consistent control logic across hardware platforms from Siemens, Schneider, Rockwell, and others.
In addition to powering Stoppage Insights, ACESYS v9 positions the ECS system for open, interoperable architectures and future-proof automation. The same structured data used by Stoppage Insights supports AI-driven process control, providing the foundation for machine learning models and advanced analytics.
The latest releases also respond to the growing risk of cyberattacks on industrial operational technology (OT) infrastructure, delivering robust cybersecurity. The latest ECS software update (version 9.2) is certified to IEC 62443-4-1 international cybersecurity standards, protecting your process operations and reducing system vulnerability.
What’s available now and what’s coming next?
The ECS/ControlCenter 9.2 and ACESYS 9 updates, featuring Stoppage Insights, are available now for:
- Greenfield projects.
- ECS system upgrades.
- Brownfield replacement of competitor systems.
Stoppage Insights will also soon integrate with our ECS/UptimeGo downtime analysis software. Stoppage records, including root cause identification and affected equipment, will flow seamlessly into UptimeGo for advanced analytics, trending and long-term reliability reporting. This integration creates a complete ecosystem for managing and improving plant uptime.
(1) The ECS Process Control Solution for cement, mining and minerals processing combines proven control strategies with modern automation architecture to optimise plant performance, reduce downtime and support operational excellence.
(2) CMMS refers to computerised maintenance management systems; ERP, to enterprise resource planning; and MES to manufacturing execution systems.
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