Dr SB Hegde, Professor and Director of Postgraduate Studies, Jain College of Engineering and Technology, Hubli, and Visiting Professor, Pennsylvania State University, USA, discusses the innovations in kiln and refractory management.
The role of kilns and refractories in meeting evolving cement production demands is paramount, as they directly influence operational efficiency, cost control, and environmental compliance. Indian cement production currently stands at over 421 million tonnes per annum (MTPA), with projections to exceed 800 MTPA by 2030, driven by urbanisation and infrastructure investments. Kiln utilisation in India averages 75 to 85 per cent, reflecting a robust demand for consistent clinker production.
Refractory costs constitute around 15 to 20 per cent of the operational expenditure in cement plants, primarily driven by frequent maintenance cycles due to high thermal loads and wear. Innovations in refractory materials, such as alkali-resistant bricks and low-cement castables, are increasingly adopted to improve kiln life, reduce downtime, and enhance heat retention. Decarbonisation has pushed plants to upgrade kiln technology, transitioning to pre-calciner systems and alternate fuels, which in turn demand advanced refractory materials to withstand chemical and thermal stresses.
Government initiatives like the National Infrastructure Pipeline (NIP) with a projected investment of `111 lakh crore and schemes like PMAY and Gati Shakti are expected to significantly boost cement demand. For example, NIP alone involves 9,300+ projects, leading to increased kiln utilisation and a sharper focus on energy efficiency and reduced emissions. Industry leaders such as UltraTech and Dalmia Bharat are investing heavily in low-carbon and energy-efficient production, with capital expenditures exceeding `12,000 crore for capacity expansion and carbon-neutral initiatives.
In alignment with global trends, Indian cement plants are also integrating smart technologies for predictive maintenance of kilns, reducing refractory wear, and optimising fuel use. Such advancements aim to lower production costs and align with the industry’s sustainability goals. This strategic emphasis positions the kiln and refractory segments as critical components in addressing the challenges of decarbonisation, cost efficiency, and operational excellence in a competitive market landscape.
Advanced Kiln Operation Strategies A. Dynamic Process Optimisation AI-Driven Kiln Control Systems: The adoption of artificial intelligence (AI) in kiln operations is revolutionising cement manufacturing by enhancing efficiency and reducing costs. Indian cement plants such as UltraTech and Dalmia Bharat have begun deploying AI-driven kiln control systems like ABB’s Advanced Process Control and FLSmidth’s Expert Optimiser. These systems leverage machine learning to adjust kiln parameters in real time, achieving higher stability and reducing fuel consumption. For instance, AI integration has demonstrated a return on investment (ROI) of up to 15 per cent within two years in energy savings alone. Data-Driven Process Modeling: Real-time data from sensors and IoT devices is now utilised for process modelling to optimise fuel mix. For example, Indian plants have achieved specific heat consumption reductions of approximately 5 per cent by fine-tuning the proportion of petcoke and coal blends using advanced algorithms. This aligns with decarbonisation goals while maintaining clinker quality. Case Study: A leading cement manufacturer in Rajasthan implemented an advanced AI kiln control system, reducing specific heat consumption from 750 kcal/kg to 712 kcal/kg of clinker, saving `20 crore annually in fuel costs while cutting CO2 emissions by 10,000 tons per annum.
B. Impact of Alternative Fuels on Kiln Dynamics Co-Processing of Waste: Indian cement plants increasingly use refuse-derived fuels (RDF) and plastic waste, aligning with sustainability objectives.
Co-processing at cement plant/s for instance, has replaced up to 15 per cent of conventional fuel with alternative fuels, saving up to 50 per tonne of clinker produced. However, these fuels pose challenges such as fluctuating flame stability and accelerated refractory wear, requiring high-performance refractory linings. Thermal Efficiency and Refractory Wear: Petroleum coke (petcoke) and biomass are widely used as alternative fuels, with petcoke offering superior calorific value but exacerbating alkali attacks on refractories. Biomass, while more sustainable, requires modified kiln burners to maintain thermal efficiency. Studies show that petcoke can reduce thermal efficiency by 3 per cent while increasing refractory maintenance costs by 10 per cent. Comparative Analysis: An Indian kiln running on coal exhibits a refractory life cycle of approximately 12 months, whereas the use of RDF and petcoke often reduces this to 8-10 months. This highlights the need for advanced refractory materials resistant to alkali and chlorine attacks common with alternative fuels. C. Advanced Material Flow Management Mitigating Coating and Ring Formation: Predictive tools based on AI and machine learning are now addressing material build-up issues such as ring and coating formation. Plants using AI systems report a 25 per cent reduction in unplanned stoppages due to excessive coating, translating into savings of `5 crore annually. Impact of Rawmix Variability: Variations in raw material chemistry, particularly silica and alumina content, affect refractory life. Data from Indian plants shows that deviations in raw mix standard deviation beyond ±1.5 per cent reduce refractory lifespan by 20 per cent. Advanced raw material blending systems, such as Schenck Process feeders, ensure consistent feed chemistry, enhancing kiln lining durability. Insights into Blending Precision: Enhanced raw material precision in an Andhra Pradesh cement plant increased refractory life by three months, yielding a cost reduction of `1.2 crore annually in maintenance expenses. Investments in XRF analysers and online quality monitoring systems are increasingly adopted to sustain these results.
These advanced strategies demonstrate the transformative potential of technology and innovation in improving kiln operations and refractory management. Integrating AI, alternative fuels, and precision raw material control positions Indian cement plants for sustainable and cost-efficient production.
Cutting-Edge Refractory Management Practices A. Innovative Refractory Materials Development of Alkali-Resistant Bricks and Coatings: Modern kilns frequently operate with alternative fuels, including refuse-derived fuels (RDF), petcoke, and biomass, which lead to increased alkali loads and vapor-phase infiltration. High alumina and magnesia-rich bricks with low silica content have become critical in managing alkali attack. These bricks incorporate additives like zircon and spinel to resist alkali penetration at temperatures above 1300°C. Recent data from Indian kilns utilising RDF indicates a refractory lifespan improvement from 10 months to 15 months with alkali-resistant linings. Furthermore, advanced ceramic coatings with a thickness of 0.5–1 mm are applied to enhance resistance to alkali-induced chemical stress and thermal spalling, particularly in the lower transition zones. High-Performance Monolithic Refractories: Monolithic refractories, specifically low-cement castables (LCCs) and ultra-low-cement castables (ULCCs), are replacing conventional bricks in various kiln sections due to their seamless structure, superior thermal shock resistance, and low porosity. In preheater and calciner zones of Indian cement plants, ULCCs have demonstrated a 25 per cent reduction in maintenance frequency. For example, at a kiln in Karnataka, LCC applications resulted in specific heat savings of 2.5 per cent, contributing to annual fuel cost reductions of `3 crore. These refractories also exhibit higher abrasion resistance, withstanding air velocities of up to 25 m/s in cyclone stages without significant wear. Nano-Structured Refractory Solutions: Nano-engineered refractory materials use ultra-fine oxides like nano-alumina and nano-zirconia, improving thermal and mechanical properties. These refractories provide enhanced creep resistance at temperatures exceeding 1400°C and reduce thermal conductivity by up to 15 per cent. Trials conducted at UltraTech Cement showed a significant reduction in heat loss through the kiln shell, enhancing overall thermal efficiency. The adoption of these materials is projected to increase by 30 per cent across Indian plants by 2030, driven by the need for higher energy efficiency. B. Proactive Refractory Monitoring Thermal Imaging and Laser-Based Shell Scanning: Advanced thermal imaging tools detect surface hotspots with precision down to 1°C. In the rotary kiln of an Andhra Pradesh plant, implementing such tools reduced undetected refractory wear by 40 per cent, leading to annual cost savings of `2.7 crore. Laser shell scanners, capable of mapping shell temperatures along the kiln’s length, have enhanced monitoring accuracy, enabling predictive maintenance schedules that minimise unscheduled shutdowns. IoT-Enabled Refractory Sensors: Real-time data acquisition through IoT-integrated sensors embedded in refractory linings provides insights into temperature gradients, heat flux, and stress distribution. These sensors use wireless communication to alert operators to potential failure points. A study at a Gujarat plant using IoT-enabled systems showed a 10 per cent improvement in refractory life, translating to savings of `1.5 crore annually. Such systems are instrumental in reducing failures caused by temperature shocks exceeding 100°C/min during emergency shutdowns. Case Study: A kiln at a major Indian cement producer integrated predictive analytics with shell temperature data. The system identified abnormal wear patterns near the kiln’s hot spot zone, enabling preemptive relining during scheduled maintenance. This proactive approach extended refractory life by 20 per cent and saved `4 crore over three years. C. Failure Mechanisms and Mitigation Thermal-Mechanical-Chemical Degradation: Refractory wear in Indian kilns is predominantly driven by the combined effects of thermal cycling, mechanical load variations, and chemical attack. Thermal cycling, particularly during start-ups and shutdowns, creates thermal shock stresses that exceed the critical tensile strength of refractories, causing cracks and spalling. High alkali content from petcoke or RDF leads to the formation of alkali sulphates and chlorides, which infiltrate and weaken the lining. Moreover, mechanical stresses from
coating dislodgement and raw material build-up exacerbate wear. Advanced Coatings for Thermal Shock and Erosion: Spinel-rich ceramic coatings with nano-bonding technology reduce thermal gradients and erosion rates by forming a thermal barrier with low thermal expansion coefficients. These coatings, applied in calciner zones, reduced thermal shock-related spalling incidents by 30 per cent at a Rajasthan plant operating with mixed-fuel inputs. R&D Case Study – Hybrid Refractory Formulations: Researchers are developing hybrid formulations combining magnesia-alumina spinels and silicon carbide (SiC) to improve resistance to thermal shock and abrasion. Trials in a Tamil Nadu plant demonstrated a 20 per cent reduction in material loss during high thermal cycling, with improved alkali resistance. Additionally, coatings incorporating graphene oxide reduced hot face temperature by 30°C, further extending refractory life.
Cost Implications and Operational Insights A. Refractory Performance vs. OPEX Breakdown: Refractory Cost per Tonne of Clinker Produced: In Indian kilns, refractory costs typically range between Rs.20 and Rs.40 per tonne of clinker, depending on the kiln size, fuel mix, and quality of refractories used. Plants employing higher-grade refractories, such as spinel-based or high-alumina bricks, report costs at the upper end of this range. For example, a kiln producing 5000 tonnes per day with advanced refractory materials incurs an annual refractory cost of Rs.6–7 crore, contributing 1–1.5 per cent of total operational expenditure (OPEX). Impact of Suboptimal Refractories on Downtime and Clinker Costs: Suboptimal refractories can lead to frequent shutdowns, increased maintenance costs, and reduced clinker output. For instance, at a plant in Gujarat, refractory failures caused by poor alkali resistance led to a 5-day unscheduled shutdown, resulting in production losses of 10,000 tonnes and a cost escalation of `4.5 crore. A subpar refractory with a lifecycle of 8 months often results in 15–20 per cent higher overall costs compared to premium options lasting 12–18 months. Comparative Study: ROI of High-Quality vs. Cheaper Refractories: High-quality refractories, while costlier upfront, deliver significantly better ROI. A Tamil Nadu plant using imported magnesia-alumina spinel bricks achieved a lifecycle extension of 24 months compared to 10 months for lower-grade bricks, reducing the total cost per tonne by
Rs.3. Advanced refractory adoption reduced clinker cost by 2 per cent, translating to annual savings of `4 crore for a 6000 TPD kiln. B. Balancing Cost with Performance Strategic Sourcing Models for Refractory Procurement in India: Indian cement plants increasingly adopt hybrid sourcing models, balancing local and imported refractories. While local refractories are cost-effective for general applications, imported options, such as European spinel or Japanese
magnesia-chrome refractories, offer superior performance in high-stress zones. Approximately 30 to 35 per cent of refractories used in premium Indian plants are imported, particularly for transition and burning zones. Impact of Bulk Procurement and Vendor Partnerships: Collaborative procurement strategies, such as long-term agreements with suppliers, provide cost advantages of up to 15 per cent. For instance, bulk procurement of low-cement castables (LCC) by a cluster of cement plants in Andhra Pradesh achieved a 12 per cent reduction in unit costs. Vendor partnerships, where payments are linked to refractory lifecycle performance, further incentivise quality. An integrated plant in Rajasthan achieved Rs.2 crore annual savings through such a model. Latest Procurement Trends: Performance-linked pricing is gaining traction in the Indian cement industry, where refractory vendors are evaluated based on key performance indicators (KPIs) such as lifecycle, downtime reduction, and clinker quality impact. In 2023, a Gujarat plant adopted this model, tying 20 per cent of payments to refractory performance metrics, achieving a 15 per cent increase in refractory lifecycle.
The integration of advanced materials and data-driven procurement practices is reshaping refractory management in Indian kilns, enabling cost-effective and reliable operations. Balancing cost with performance requires a nuanced approach, leveraging high-quality materials, strategic partnerships, and performance-focused contracts.
Sustainability and Decarbonisation A. Low-Carbon Kiln Operations Reduction in Thermal Losses: Advanced refractories significantly minimise thermal losses in cement kilns, leading to reduced specific heat consumption. High-performance materials such as spinel-based and nano-bonded refractories have thermal conductivities 20 to 30 per cent lower than conventional options. For instance, an Indian cement plant in Madhya Pradesh reported a 6 per cent reduction in fuel consumption after upgrading its burning zone with high-alumina refractories engineered for higher insulation properties. This translates to a savings of approximately Rs.3.5 crore annually for a 6000 TPD kiln. CO2 Emissions Reduction: By lowering fuel requirements, advanced refractories indirectly contribute to CO2 emission reductions. A case study from a leading cement manufacturer in Tamil Nadu showed that using ultra-low thermal conductivity refractories resulted in 0.1 tonnes of CO2 reduction per tonne of clinker, equivalent to a 5 per cent reduction in total emissions. This approach aligns with India’s commitment to reducing cement industry CO2 intensity by 45 per cent by 2050 under the Paris Agreement targets. B. Recyclability of Spent Refractories Recycling Spent Refractories into Raw Meal: Recycling initiatives are gaining traction in India as a means of improving sustainability and reducing raw material dependency. Spent refractories containing alumina and silica are increasingly being reused in kiln feedstock. For example, Dalmia Cement’s Ariyalur plant implemented a spent refractory recycling program, processing 300 tonnes annually into raw meal, resulting in savings of `2 crore in virgin material costs. Economic Feasibility in Cost-Sensitive Markets: The recycling of refractories faces economic challenges, particularly in cost-sensitive regions. However, the adoption of efficient grinding and sorting technologies has made recycling viable. With an investment of Rs.50 lakhs in specialised equipment, one Karnataka-based plant reduced refractory disposal costs by 50 per cent while achieving a 10 per cent raw material cost offset.
C. Green Refractory Innovations Development of Low-Carbon Refractories: Emerging R&D focuses on reducing the embodied carbon in refractories through alternative raw materials and production methods. For instance, magnesia-carbon refractories manufactured with bio-based binders instead of phenolic resins have shown a 15 per cent reduction in lifecycle carbon emissions. Adoption of these materials has started in premium plants in Maharashtra and Gujarat, which aim to lower their overall carbon footprint. Adaptation of Global R&D for Indian Conditions: Globally, innovations such as non-chrome refractories and geopolymers are being adapted for Indian conditions. A collaboration between a Japanese refractory giant and an Indian manufacturer has led to the development of chrome-free bricks resistant to alkali and thermal shocks, optimised for kilns using Indian raw materials. Initial trials in Andhra Pradesh indicate a 20 per cent lifecycle improvement and a 25 per cent reduction in embodied carbon compared to conventional chrome-bearing options.
These advancements in kiln and refractory management underscore the cement industry’s ability to align operational goals with sustainability targets, paving the way for a greener, more efficient future.
Technological Advancements A. Digital Twins for Kiln and Refractory Management Simulating Refractory Wear and Optimising Kiln Performance: Digital twins replicate kiln operations virtually, enabling precise monitoring of refractory conditions and predictive analysis of wear patterns. These simulations help optimise operational parameters like fuel flow, rotational speed, and air distribution. In India, ACC Cement has implemented digital twins in a pilot project at its Wadi plant, reducing refractory failure rates by 15 per cent and increasing kiln availability by 8 per cent. Pilot Projects in India: A key success story is UltraTech Cement’s adoption of digital twins at its Rawan plant. The system predicted hotspots leading to thermal degradation, allowing the team to preemptively reline sections of the kiln, saving Rs.1.2 crore annually in downtime and material costs. These projects show significant promise for widespread adoption, particularly in plants operating at >90 per cent capacity utilisation. B. AI and Machine Learning Applications Predictive Maintenance Tools for Refractory Performance: AI-driven tools analyse historical data on temperature, load, and chemical exposure to predict refractory life. For example, JSW Cement employs an AI-powered maintenance system that combines real-time thermal imaging with historical failure data, resulting in a 20 per cent reduction in unplanned maintenance events and Rs.1 crore annual savings. ML-Based Algorithms for Failure Prediction: Machine learning algorithms have proven effective in identifying patterns of high-temperature zone failures, particularly in plants co-processing alternative fuels. At a Gujarat plant, a predictive model flagged potential failures in the burning zone 30 days in advance, allowing for targeted interventions.
This proactive approach increased refractory lifespan by 10 per cent, reducing replacement costs byRs.50 lakhs annually. C. Emerging Refractory Materials Ultra-High-Temperature Refractories for Newer Kiln Designs: Innovations in materials science have led to the development of ultra-high-temperature refractories capable of withstanding 2000°C without spalling or significant wear. Indian plants utilising these materials in kilns designed for alternative fuels have reported significant benefits. For instance, a Dalmia Cement plant in Tamil Nadu introduced nano-ceramic bonded bricks, resulting in a 25 per cent improvement in thermal efficiency and a 15 per cent extension in refractory life. Case Study: Extending Refractory Life by 30 per cent: A Tier-1 cement plant in Rajasthan collaborated with a Japanese manufacturer to adopt magnesia-spinel bricks tailored for local kiln conditions. These advanced refractories not only extended the lining’s life by 30 per cent but also reduced fuel consumption by 5 per cent, yielding annual savings of Rs.2.5 crore.
The integration of digital twins, AI, and advanced materials underscores the cement industry’s commitment to leveraging technology for operational excellence. These advancements are driving cost efficiency, sustainability, and reliability in an increasingly competitive market.
Advanced R&D Insights A. Collaborations and Innovations Indian Cement Industry Partnerships: Indian cement manufacturers are increasingly collaborating with refractory suppliers to develop tailored solutions that address the specific challenges of local kiln conditions, such as high thermal gradients and the use of alternative fuels. For example, Shree Cement partnered with RHI Magnesita to develop specialised refractories for kilns using petcoke. This collaboration resulted in a 15 per cent increase in refractory lifespan and a 10 per cent reduction in downtime. Cross-Industry R&D on Refractory Chemistry: Cross-industry research is driving innovations in refractory chemistry, with Indian firms collaborating with global players in steel and glass sectors. A notable initiative is the Tata Steel Research Centre’s partnership with UltraTech Cement to study thermal shock resistance in refractories, leading to a hybrid solution that combines the properties of magnesia and alumina. Initial trials indicate a 12 per cent improvement in thermal resilience under high-stress conditions. B. Experimental Developments Computational Modeling for High-Stress Zones: Advanced computational models are being used to simulate the behavior of refractories under extreme conditions, including high-temperature gradients and chemical attack. In a joint project by Birla Institute of Technology and Indian cement manufacturers, finite element analysis (FEA) was employed to predict wear patterns in rotary kilns. This research reduced the frequency of unplanned shutdowns by providing accurate wear predictions. Minimising Alkali-Silica Reactions: Experimental research on alkali-silica reactions (ASR) caused by petcoke ash is gaining momentum. Studies conducted at CSIR-Central Glass & Ceramic Research Institute revealed that introducing zircon-based additives to refractories mitigates ASR-related damage, enhancing the durability of bricks by 20 per cent. Plants in Gujarat and Rajasthan have begun implementing these findings, with promising results in reducing kiln maintenance cycles. C. Global vs. Indian Trends Comparative R&D Budgets: Global leaders in the refractory industry, such as Vesuvius and Saint-Gobain, allocate 4–6 per cent of annual revenue to R&D, while Indian counterparts, including local refractory manufacturers, typically spend less than 1 per cent. For example, in 2023, RHI Magnesita invested €50 million globally in refractory R&D, compared to Rs.30 crores by the top Indian manufacturers collectively. Lessons from Global Practices: Global refractory management practices emphasise predictive maintenance and advanced material science, with significant adoption of AI-based tools and robotics. Indian plants are gradually adapting these practices, with Ambuja Cement and ACC implementing robotic refractory installation systems in select kilns. While adoption remains limited, these innovations have reduced installation times by 25 per cent and increased overall safety.
These R&D advancements, collaborations, and global benchmarking efforts are setting the stage for the Indian cement industry to overcome traditional limitations and achieve greater efficiency, sustainability, and competitiveness in kiln and refractory management.
Future of Kiln and Refractory Management in India Adoption of Circular Economy Principles in Refractory Usage: The Indian cement industry is moving towards circular economy models, focusing on the reuse, recycling, and repurposing of spent refractories. Traditionally discarded as waste, spent refractories are now being processed for use as secondary raw materials in clinker production. For instance, ACC Cement and UltraTech have implemented systems to integrate 30–40 per cent of spent refractories into raw meal blends, reducing dependence on virgin materials. This initiative aligns with India’s commitment to reducing industrial waste and has the potential to cut refractory disposal costs by `15–20 crore annually across the industry. Globally, advanced recycling technologies have demonstrated significant success. Indian manufacturers are collaborating with international players like Vesuvius to bring these technologies into the domestic market. Research indicates that widespread adoption of refractory recycling could lead to annual savings of Rs.500–700 per tonne of clinker produced in India. Vision 2030: Energy-Efficient Kilns and Next-Gen Refractories: The Indian cement industry’s “Vision 2030” emphasises the adoption of ultra-modern kilns capable of achieving thermal efficiencies beyond 85 per cent. These kilns will require next-generation refractories with high thermal insulation and resistance to alternative fuel residues. Nano-engineered refractories are expected to play a critical role in this transformation, with pilot projects already showing a 10–15 per cent increase in energy efficiency. As of 2024, India’s average thermal energy consumption for clinker production stands at 720 kcal/kg clinker, compared to global benchmarks of 650 kcal/kg. Adoption of advanced refractories is projected to bridge this gap, saving up to `25 per tonne of clinker. The increased durability of these materials will also reduce kiln downtime, improving overall plant productivity by 5–7 per cent. Predictions: Cost Savings and Emission Reductions with New Refractory Technologies: Advanced refractory materials and kiln technologies are forecasted to yield significant cost and environmental benefits by 2030. By implementing cutting-edge materials like high-alumina and magnesia-spinel bricks, Indian plants could achieve annual cost savings of `1,000–1,500 crore collectively through reduced maintenance and enhanced thermal efficiency. Emission reductions are also a critical area of impact. Studies indicate that optimising refractory performance can lower CO2 emissions by 0.02–0.05 tonnes per tonne of clinker produced. For an industry producing 350 million tonnes annually, this translates to an annual reduction of 7–17.5 million tonnes of CO2, supporting India’s broader climate goals under the Paris Agreement.
Conclusion
The adoption of advanced kiln operation strategies and refractory management practices is no longer optional but essential for the Indian cement industry to remain competitive in an evolving global landscape. Advanced digital tools such as AI-driven control systems and digital twins have demonstrated significant operational efficiencies, reducing specific heat consumption by 5–10 per cent and increasing clinker quality consistency. Simultaneously, the integration of high-performance refractory materials has enhanced durability and reduced maintenance costs, saving up to `1,000–1,500 crore annually across the industry. Sustainability is at the core of these advancements. Recycling initiatives for spent refractories and the development of low-carbon refractory materials are paving the way for a circular economy, contributing to a reduction of 7–17.5 million tonnes of CO2 annually. As Vision 2030 unfolds, the alignment of refractory technologies with India’s carbon neutrality goals will help cement plants achieve significant energy efficiency gains and meet stringent environmental targets.
In conclusion, industry-wide adoption of these innovative practices is imperative. While the upfront investment in advanced refractories and digital technologies might seem substantial, the long-term benefits in cost savings, operational excellence, and environmental impact far outweigh the initial costs. By embracing these solutions, the Indian cement industry can set global benchmarks for sustainability and efficiency, ensuring its growth and relevance in a carbon-conscious world.
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ABOUT THE AUTHOR: Dr SB Hegde is an industrial leader with expertise in cement plant operation and optimisation, plant commissioning, new cement plant establishment, etc. His industry knowledge cover manufacturing, product development, concrete technology and technical services.
Nuvoco Vistas opens a 2 MMTPA grinding unit at Limla, entering Gujarat and advancing its target of 35 MMTPA capacity by FY 2028.
Surat (Gujarat)
Nuvoco Vistas Corporation Ltd, a part of Nirma Group and one of India’s leading building materials company, has inaugurated the Limla Cement Plant in Surat (Gujarat), one of Vadraj Cement Limited’s (VCL) principal manufacturing facilities. The commissioning represents a key milestone in Nuvoco’s acquisition and restoration of VCL, while supporting the company’s expansion across the Western Indian cement market.
Vadraj Cement Limited is a subsidiary of Nuvoco Vistas Corporation Limited and has installed cement capacity of 6 MMTPA across its assets. The Limla inauguration therefore represents the first operational step in the acquired platform’s wider revival, while the Kutch facilities provide clinker supply, mineral security and coastal logistics support for the western business.
Nuvoco completed its acquisition of Vadraj Cement Limited, then under the Corporate Insolvency Resolution Process, after paying a consideration of Rs 1,800 crore in June 2025. VCL’s asset portfolio comprises a clinker unit at Kutch and a grinding unit at Limla in Surat. It also includes high-quality captive limestone reserves and a captive jetty at Kutch, supporting more efficient logistics. Following the takeover, Nuvoco began an extensive programme of restoration, refurbishment and expansion at both locations, leading to the commissioning of the Limla plant.
The Limla Cement Plant is expected to support a phased increase in sales volumes across Gujarat. It will also help Nuvoco supply neighbouring markets in Western Maharashtra and release cement capacity from its northern plants, which can consequently be redirected towards markets in North India. The plant will manufacture a full portfolio comprising Ordinary Portland Cement, Portland Slag Cement, Portland Pozzolana Cement and Portland Composite Cement. It will additionally produce the complete Nuvoco Duraguard range, including the premium Nuvoco Duraguard Microfibre product. The acquisition is also expected to generate operational synergies with Nuvoco’s existing plants at Nimbol and Chittorgarh in Rajasthan, improving logistics optimisation and market reach across important regional markets.
The grinding unit at the Limla Cement Plant was completed ahead of schedule, with 2 MMTPA of capacity now inaugurated to expand Nuvoco’s operating scale and customer reach. After Vadraj Cement’s assets become fully operational, plants in North and West India are expected to account for nearly 40 per cent of Nuvoco’s total cement capacity. This will broaden the company’s manufacturing network, strengthen access to high-growth markets and support its plan to increase consolidated cement capacity to 35 MMTPA by FY 2028, reinforcing its longer-term growth strategy.
Commenting on the development, Jayakumar Krishnaswamy, Managing Director, Nuvoco Vistas Corp Ltd, said: “The inauguration of the Limla Grinding Unit in Surat is an important milestone in Nuvoco’s growth journey and demonstrates our commitment to disciplined, value-accretive expansion. Gujarat is strategically significant for Nuvoco, with substantial opportunities arising from infrastructure investment, industrial growth, rapid urbanisation and continuing demand from the housing and construction sectors. The facility strengthens our regional footprint, improves operational flexibility and increases our ability to serve customers across northern and western markets with greater reliability and efficiency.”
He added: “Through the Vadraj acquisition, we have refurbished and restarted a strategically important asset, returning it to operations in record time through strong execution and collaboration between teams. The achievement demonstrates our ability to create value from acquired assets, fulfil our commitments and retain the confidence of stakeholders. It also highlights the strength of our project delivery capabilities and our continued focus on building sustainable, profitable growth over the long term.”
Nuvoco Vistas Corporation Limited is a building materials company whose vision is to build a safer, smarter and more sustainable world. It is among the leading players in East India and has a significant presence across North and West India. Nuvoco began operations in 2014 with a greenfield cement plant at Nimbol, Rajasthan. It later acquired Lafarge India Limited, which had entered India in 1999, followed by Emami Cement Limited in 2020 and Vadraj Cement Limited in April 2025. The company has also announced an expansion in eastern India through a new grinding mill at the Arasmeta Cement Plant, supported by several debottlenecking programmes involving equipment upgrades, process improvements and internal capacity initiatives. These developments place Nuvoco on track to achieve total cement capacity of approximately 35 MMTPA. The company reported total income of Rs 11,362 crore in FY 2025-26, reflecting its continuing growth trajectory.
Nuvoco operates a diversified portfolio across three segments: Cement, Ready-Mix Concrete and Modern Building Materials. Its cement portfolio includes Concreto, Duraguard, Double Bull, PSC, Nirmax and Infracem, covering Ordinary Portland Cement, Portland Slag Cement, Portland Pozzolana Cement and Portland Composite Cement. Its pan-India RMX business provides value-added products under Concreto for performance concrete, Artiste for decorative concrete, InstaMix for ready-to-use bagged concrete, X-Con covering M20 to M60 grades, and Ecodure for specialised green concrete. Nuvoco has supplied materials to projects including the Mumbai-Ahmedabad Bullet Train, Birsa Munda Hockey Stadium in Rourkela, Aquatic Gallery at Science City in Ahmedabad, and metro railway projects in Delhi, Jaipur, Noida and Mumbai.
Indian Cement Review (ICR) and Fuller Technologies brought industry, policy and technology leaders together to discuss how cement innovation can drive green construction at scale, writes Rakesh Rao.
India is building at a pace few countries can match. Highways, airports, housing, logistics parks, industrial corridors and urban infrastructure are reshaping the country’s economic geography. But beneath this growth story lies a difficult question: can India continue to build at scale without locking itself into a high-carbon future?
That question formed the core of an online panel discussion titled “Driving Green Construction Through Cement Innovation”, organised by Indian Cement Review (ICR) in association with Fuller Technologies as the Presenting Partner on June 25, 2026. The webinar brought together experts from cement technology, R&D, global industry platforms, building performance policy and international development cooperation to examine how low-carbon cement and material innovation can accelerate India’s green construction transition.
The discussion came at a crucial time. India has committed to achieving net-zero emissions by 2070 and reducing the carbon intensity of its economy by 45 per cent by 2030. At the same time, the country’s construction sector is expanding rapidly, driven by urbanisation, infrastructure development, housing demand and industrial growth. Cement, as one of the most widely used construction materials, sits at the heart of this transition. It is indispensable to development, but also central to the challenge of reducing embodied carbon in buildings and infrastructure.
Moderated by Nitika Krishan, Senior Urban Infrastructure and Sustainable Policy Consultant, the panel featured:
Dr Hemantkumar Aiyer, VP and Head R&D, Nuvoco Vistas Corp Ltd;
Devika Wattal, Innovation Lead, Global Cement and Concrete Association (GCCA);
Dr Sunita Purushottam, MD, GBPN India (Global Buildings Performance Network); and
Vaibhav Rathi, Senior Technical Advisor, GIZ (the German Agency for International Cooperation)
Setting the tone for the discussion, Nitika Krishan underlined the scale of the challenge before the sector. “The question before us is no longer whether we build, but how we build sustainably,” she said. She pointed out that construction accounts for nearly 40 per cent of global energy-related carbon emissions when both operational and embodied carbon are considered. Cement production, she added, remains one of the hardest industrial processes to decarbonise.
For India, this is not merely an environmental issue. It is a development issue, a competitiveness issue and increasingly, a market issue. As one of the world’s largest cement producers and among the fastest-growing construction markets, India’s material choices will influence the carbon trajectory of its built environment for decades. As Krishan observed, sustainability solutions in economies such as India must not remain limited to laboratory success. They must be scalable, commercially viable and practical at national level.
The innovation gap: From technology to market
Experts believe that there is a need to bridge the innovation gaps for making decarbonisation in cement and concrete scalable. Devika Wattal of GCCA, explained, “The starting point must be the core cement manufacturing process itself. The first and foremost is the heart of our process, the heart of cement manufacturing. How do we reduce clinker? That is always a topic where industry is working very intrinsically.”
Clinker reduction remains one of the most important pathways for lowering emissions in cement. Since clinker production is energy-intensive and chemically emits carbon dioxide, reducing the clinker factor through supplementary cementitious materials (SCMs), blended cements and new chemistries can have a significant impact. Wattal also noted that carbon capture, utilisation and storage (CCUS) will have a role, though it may not be the first lever for all markets.
However, she stressed that innovation cannot stop at technology development. A solution that works in the lab must also be adaptable to industry, scalable in production and acceptable in construction practice. “It is important for that innovation to be adaptable, to be scalable, and so that it can be executed in real time,” she said.
Wattal also called for stronger enabling systems around innovation. These include performance-based standards, product-level embodied carbon databases and clearer frameworks for evaluating green materials. Without these, low-carbon cement products may struggle to compete with conventional materials in procurement and design.
R&D must balance carbon, cost and performance
Bringing in the R&D perspective into the discussion, Dr Hemantkumar Aiyer of Nuvoco Vistas emphasised that low-carbon cement development cannot be treated as a single-variable exercise. Cement must perform in real construction conditions. It must deliver strength, durability, consistency and cost competitiveness, while also reducing carbon.
“The root of understanding and balancing all these aspects lies in materials, and knowing the materials,” he said.
According to Dr Aiyer, R&D teams must understand the variability of raw materials such as fly ash, slag and clinker. Different sources produce different material behaviours. This makes mix optimisation, material characterisation and processing-property relationships critical. When performance is affected, cement manufacturers must understand how strength enhancers, admixtures and other performance chemicals interact with the material system.
He also linked material science with process efficiency. Clinkerisation takes place at extremely high temperatures, around 1,400 to 1,450 degrees Celsius. Any improvement in raw mix design, process control or energy optimisation can, therefore, help reduce emissions and cost. Dr Aiyer pointed to artificial intelligence-based optimisation, Cement 4.0 tools and advanced software as important enablers for real-time process and material control.
“The more you understand the materials, the more you can control it,” he said.
LC3: The promise is proven, the sequencing is not
Limestone calcined clay cement, commonly referred to as LC3, has attracted global attention because it can reduce clinker content significantly by using calcined clay and limestone while maintaining performance in many applications. Kiranmai Sanagavarapu of Fuller Technologies said the technology itself has already moved beyond proof of concept. Fuller Technologies has worked with calcined clay technology for nearly two decades and has seen plants running in France and Ghana. These plants, she said, are meeting local and national specifications, while the economics are beginning to make sense.
“The calciner is performing, the economics is stacking up, it is making business sense to produce,” she said.
But if the technology is viable, why has adoption not scaled faster? For Sanagavarapu, the answer lies in project sequencing. Too often, clay characterisation happens after equipment is specified. This, she warned, is a backward approach because calciner design depends on clay mineralogy, kaolinite content, iron levels, reactivity, moisture and other variables.
“If you don’t know what your deposit looks like before you commit for the equipment, you are, in a way, going blind into designing,” she said.
She also identified permitting and plant integration as major bottlenecks. Environmental clearances, mining permissions and local regulatory approvals must begin early. Similarly, calcined clay must be integrated into existing grinding, blending and logistics systems from the design stage, not treated as an afterthought during commissioning.
India already has IS 18189:2023 standard for LC3, but Sanagavarapu pointed out that the standard is not yet visible enough in procurement documents. “The gap between what is technically being permitted and what the procurement is asking is the single biggest bottleneck,” she said.
In her view, successful scale-up depends on getting the sequence right: clay characterisation first, permitting in parallel, standards aligned with construction, and integration built into plant design.
India’s LC3 journey: Progress, but demand remains thin
Providing details of India’s LC3 commercialisation experience, Vaibhav Rathi of GIZ noted that JK Cement carried out the first commercial production of LC3 at its Rajasthan plant, followed by JK Lakshmi Cement three months later. These initiatives were supported by the International Climate Initiative of the Government of Germany, with IIT Delhi contributing deep institutional knowledge on LC3 research and BIS certification.
Rathi said India’s early experience has produced clear lessons. One of the biggest was the need to build capacity among regulators. While BIS certification existed, State Pollution Control Boards were unfamiliar with the technology and unsure about the approval pathway.
“The capacity building is not just needed amongst the producer and the users of the cement, but also the regulators who are working with this technology for the first time,” he said.
He also highlighted the need for better information on China clay deposits. Since China clay is currently classified as a minor mineral, centralised data on availability, quality and location is limited. If cement manufacturers are to adopt LC3 at scale, stronger mineral intelligence will be important.
The third issue is demand. LC3 has already been used in projects such as Palava City in Mumbai and Noida International Airport, but these remain limited examples. “It is in a chicken and egg situation,” Rathi said. “Cement companies are saying we need more demand, and users are saying there is not enough cement available.”
Public procurement, he suggested, could help break this cycle. If agencies such as CPWD and other public bodies begin testing, accepting and specifying LC3, it could create the market confidence needed for cement companies to invest in production and storage.
Building codes must catch up with innovation
Dr Sunita Purushottam of GBPN India argued that material choices will determine built environment emissions over the long term, but India’s current policy signals remain fragmented. Although LC3 has received BIS recognition, she pointed out that building codes, municipal bylaws, schedules of rates and sustainability codes do not yet provide uniform guidance on low-carbon cement.
“The current cement regulations are largely prescriptive and favouring traditional materials,” she said. This limits the ability of alternative materials to compete on performance, durability and emissions.
Dr Purushottam also raised the issue of taxation. Cement, including LC3, currently falls under the same GST bracket as conventional cement. A differentiated tax structure, she argued, could help accelerate market adoption. “In order for the market to demand LC3, that differentiation in the GST could go a long way,” she said.
She noted that green building certifications such as IGBC and GRIHA are already creating demand for low-carbon materials by assigning points for embodied carbon and sustainable material use. However, she said large-scale adoption will require regulatory mandates, particularly through building codes and state-level notifications.
She also cautioned that low-carbon cement alone does not solve the entire building performance problem. A material may reduce embodied carbon, but the operational carbon of a building depends on thermal performance, design, insulation and energy use. “The energy part has two elements,” she said. “One is the embodied carbon of the material itself, and the other is the operational carbon.”
Collaboration is the bridge between invention and impact
Wattal said GCCA sees innovation as a strategic priority and works through platforms that connect industry with academia and start-ups. “There is no way we will decarbonise our sector without innovation,” she said.
However, she stressed that research must be connected to actual industry challenges. Innovations developed in isolation may fail when they encounter real-world barriers such as raw material variability, plant integration, cost, standards and finance. Start-ups, too, need industry mentorship and scale-up pathways.
Wattal also flagged the importance of finance. Even strong technologies may struggle to attract investment if there is no common understanding of bankability. “We have always put projects into, is this a bankable project? But the definition of a bankable project has never been defined,” she said.
For India, she saw strong potential in its academic and start-up ecosystem, but said the challenge lies in alignment and prioritisation. The country has the research base, industrial capacity and market size. What it now needs is a coordinated route from innovation to deployment.
There is a practical concern for cement manufacturers: how can existing plants be adapted for lower emissions without compromising reliability or commercial viability?
Kiranmai Sanagavarapu addressed, “The reliability risk in calcined clay retrofit is definitely real, but it is almost always self-inflicted. The risk arises when a new process is added to an existing circuit without properly redesigning grinding and blending configurations.”
Existing cement plants, she explained, can take two broad routes. The first is external sourcing of calcined clay combined with mill optimisation. This requires lower capital investment and can potentially move in 12 to 18 months if other conditions are in place. It may reduce emissions by around 20 to 30 per cent. The second route is integrated calcination on site, which requires higher capital expenditure and longer lead times, but provides greater control over quality, supply and emissions reduction potential.
For Sanagavarapu, the principle is simple: low-carbon retrofits must be designed with intent. “Design it with an intent properly from the start. Start in the market conditions where the economics are already working,” she said.
Circularity: The overlooked advantage
According to Vaibhav Rathi, fly ash and slag are already well established in cement and construction (C&D), but construction and demolition waste remains underutilised. “C&D waste is a growing business opportunity which not many have taken up,” he said. India’s continuous construction and demolition activity creates huge volumes of waste, much of which contributes to air pollution, land degradation and material inefficiency. With the right processing and standards, this waste can be converted into useful construction products.
Rathi also pointed out that LC3 has a circular economy dimension that is often overlooked. It can use low-grade kaolin-rich clay left behind after high-grade clay is extracted for other applications. “LC3 is not only a low-carbon solution, but also a circular economy solution,” he said.
At the same time, he cautioned that LC3 in India is not yet cheap because it has not reached scale. Site-specific techno-commercial feasibility studies, supported jointly by development agencies and industry, could help companies assess whether LC3 production makes technical and financial sense at a given location.
Dr Purushottam added that India must address both low-carbon cement and construction waste together. “Both low-carbon cement and C&D waste go hand in hand. India does not have an option but to work on both,” she said.
Dr Aiyer called for policy shifts from both government and industry, including preferential purchasing of sustainable materials, minimum supplementary cementitious material requirements in public and public-private projects, and faster regulatory implementation. “If we can fast-track the regulatory standards and their implementation on the ground, that is the way to go,” he said.
From green ambition to green construction
Cement innovation is no longer only about chemistry. It is about systems. Low-carbon cement will scale only when technology, standards, procurement, finance, regulation, education and construction practice move together.
LC3 and other low-carbon technologies have shown promise. India has early commercial examples, strong research capability and growing market interest. But mainstream adoption will depend on whether demand can be created, regulators can be capacitated, standards can be embedded in procurement, and manufacturers can see a clear business case.
For a country building at India’s scale, the opportunity is enormous. Cement will continue to be central to infrastructure and urban development. The challenge now is to ensure that the cement used in India’s growth story carries a lower carbon burden.
Rakesh Rao
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Specialised rail logistics will move fly ash from power plants to infrastructure industries.
New Delhi
Indian Railways is planning a large-scale green logistics initiative to transport fly ash from thermal power plants to industries where it can be reused in infrastructure and construction activities.
The initiative was discussed during a review meeting chaired by Union Minister for Railways Ashwini Vaishnaw. Union Ministers of State for Railways V Somanna and Ravneet Singh Bittu were also present.
India generates nearly 340 million tonnes of fly ash every year from thermal power plants. The proposed initiative aims to create an efficient rail-based transport system using specialised containers and dedicated logistics arrangements to move fly ash safely from power plants to end-use industries.
Fly ash is widely used in road construction, cement manufacturing, brick production, concrete, blocks and boards. By improving its movement through the railway network, the initiative is expected to support better utilisation of this industrial by-product while reducing environmental concerns linked to storage and disposal.
The move also aligns with India’s circular economy goals by converting waste from thermal power generation into a useful raw material for the construction and infrastructure sectors. Wider availability of fly ash can help reduce material costs in areas such as bricks and cement, supporting more affordable infrastructure and housing development.
Through this initiative, Indian Railways aims to provide a cleaner, safer and more organised transport solution for fly ash, turning an environmental challenge into an infrastructure resource.
