Dr SB Hegde discusses the importance of grinding aids as essential chemical additives that enhance cement grinding efficiency, reduce energy consumption and improve overall cement quality in the concluding part of his article.

Grinding aids represent a critical segment of the cement additives market, driven by their ability to enhance grinding efficiency, reduce energy consumption, and improve cement quality. The market dynamics of grinding aids vary significantly across regions, influenced by economic growth, cement production capacities and regulatory environments.

Global market size and growth projections
The global grinding aids market was valued at approximately US $ 1.2 billion in 2023 and is expected to grow at a CAGR of 5.5 per cent from 2023 to 2030, reaching nearly US $ 1.8 billion by 2030.
This growth is fueled by the increasing focus on energy efficiency and sustainable cement production practices worldwide.
Rapid urbanisation and infrastructure development, especially in emerging economies, are major growth drivers. Cement producers are increasingly adopting grinding aids to address rising energy costs, reduce carbon footprints, and improve production efficiencies. For instance, grinding aids have been shown to lower energy consumption by up to 25 per cent, making them a cost-effective solution for plants facing energy price volatility.

Regional trends: Developed vs. developing markets

• Developed markets: Europe and North America represent mature markets for grinding aids. Europe, driven by stringent environmental regulations such as the EU Emissions Trading System (EU ETS), has witnessed a steady rise in the adoption of low-VOC and eco-friendly grinding aids. Leading players in these markets emphasise sustainability and compliance with regulatory frameworks, contributing to steady demand.
  In North America, the focus is on productivity enhancements in large-scale cement plants, with grinding aids used to achieve finer cement grades and support blended cement production.
• Developing markets: Emerging economies in Asia-Pacific, the Middle East, and Africa exhibit the fastest growth in grinding aid adoption. The Asia-Pacific region accounted for over 40 per cent of global grinding aid consumption in 2023, with countries like India, China, and Vietnam leading the way. The rapid urbanisation, rising construction activity, and increasing cement production capacities in these regions are
  driving demand.

In Africa, grinding aids are gaining traction as manufacturers focus on optimising production costs in an environment of fluctuating raw material and energy prices.

Market size and adoption rate in India
India, the world’s second-largest cement producer, offers a significant growth opportunity for grinding aids. In 2023, the grinding aids market in India was valued at US$ 150 million, with a projected growth rate of over seven per cent CAGR through 2030. The adoption rate remains relatively low at smaller plants, which prioritise cost-saving over efficiency gains. However, leading manufacturers and integrated cement plants are increasingly embracing grinding aids, particularly for blended cement production.
Blended cements, such as Portland Pozzolana Cement (PPC) and Portland Slag Cement (PSC), account for more than 70 per cent of the Indian cement market. Grinding aids tailored for fly ash and slag-blended cements are in high demand, with some products delivering up to a 15 per cent increase in mill throughput and improved early strength development.

Emerging trends

• Eco-friendly formulations: The growing demand for sustainable grinding aids has prompted companies to develop low-VOC and biodegradable alternatives.
• Customised solutions: Grinding aid formulations are increasingly tailored to address specific raw material challenges and production processes, such as VRMs or high-SCM cement blends.
• Digitalisation: Smart dosing systems integrated with real-time mill monitoring are enabling optimised grinding aid usage, ensuring consistent performance across diverse production conditions.

Bridging the Trust Gap
For cement plant operators, the quality and performance of grinding aids often appear as a ‘black box.’ The lack of transparency in the formulation and quality checks of these additives has historically limited trust and widespread adoption. Grinding aid manufacturers must address this issue by fostering transparency and providing detailed insights into the testing and validation of their products. This would not only instill confidence but also strengthen collaboration with cement companies.
Grinding aid producers should provide robust documentation outlining the physical and chemical characteristics of their formulations, supported by consistent performance data from laboratory tests, industrial-scale trials, and third-party validations. This transparency is essential to demystify grinding aids’ performance and demonstrate their effectiveness across diverse operational conditions.

Emerging innovations in grinding aid chemistry
The path forward for grinding aid manufacturers lies in innovation. Recent research highlights the potential of hybrid formulations combining traditional amines and glycols with advanced polymeric additives like polycarboxylate ethers (PCEs). These hybrid products can address specific challenges such as improving grindability in blended cements containing fly ash or slag, where traditional additives often underperform. Nano-engineering of grinding aids, incorporating nanoparticles for optimised dispersion and enhanced hydration kinetics, represents another promising avenue.

Leveraging AI for optimisation

The integration of artificial intelligence (AI) and machine learning tools into grinding aid application systems is reshaping the cement industry. AI-driven systems enable real-time optimisation of grinding aid dosages by analysing mill performance data, such as power consumption, throughput, and particle size distribution. For example, a cement plant in Europe reported a 15 per cent reduction in specific energy consumption and a 10 per cent
increase in mill throughput using AI-optimised dosing systems. This innovation reduces operational variability and improves the predictability of grinding aid performance.

Expectations from grinding aid producers
The cement industry demands more than just products; it seeks partnerships with grinding aid manufacturers. Key expectations include:
1. Customised formulations: Tailored products designed for specific raw materials, clinker compositions, and mill configurations to maximise efficiency and performance.
2. Eco-friendly additives: Grinding aids with low volatile organic compound (VOC) emissions and biodegradable ingredients that align with the industry’s sustainability goals.
3. Comprehensive technical support: On-site training and technical services to help plant operators understand grinding aid chemistry, application techniques and performance optimisation strategies.
4. Advanced quality control systems: Transparent testing protocols, including real-time quality assurance of grinding aids delivered to cement plants. Regular reporting of performance consistency through defined KPIs like grindability index and Blaine fineness is essential.

Role of cement companies in promoting grinding aid usage
Cement producers must take an active role in promoting grinding aid adoption. Sharing success stories of energy savings, improved mill performance, and enhanced cement quality can encourage industry-wide adoption. For example, an Indian cement manufacturer recently documented a 20 per cent improvement in 28-day compressive strength and a 10 per cent reduction in energy consumption with glycol-based additives, driving interest among peers.
Moreover, collaborative initiatives between cement producers and grinding aid manufacturers, such as joint research programs and knowledge-sharing forums, could lead to significant advancements in grinding technology. Organisations like the Cement Manufacturers’ Association of India and the World Cement Association can facilitate these partnerships.

Conclusion
Grinding aids play a pivotal role in modern cement manufacturing, offering significant advantages in energy efficiency, mill productivity and cement quality. Despite their transformative potential, adoption remains inconsistent due to challenges like raw material variability, operational concerns and limited trust in product formulations. Transparency and collaboration between grinding aid producers and cement manufacturers are critical to addressing these issues and fostering broader acceptance.
Innovations in grinding aid chemistry, including hybrid formulations and nano-engineered additives, have unlocked new possibilities for enhancing grindability and hydration performance. Meanwhile, advancements in artificial intelligence and data analytics have opened avenues for real-time optimisation, ensuring precise dosing and measurable cost savings. These developments underscore the evolving synergy between technology and grinding aid applications.
Globally, the grinding aid market is poised for growth, with developed regions leading adoption and emerging economies like India offering immense potential driven by infrastructure demands. However, tapping into these opportunities requires grinding aid producers to align with industry expectations. Cement manufacturers expect customised solutions, eco-friendly formulations, technical support and transparent quality assurance processes to build trust and confidence.
The path forward demands a collaborative approach. Grinding aid producers must continue investing in research and innovation while actively engaging with the cement industry to educate stakeholders and demonstrate measurable benefits. Concurrently, the cement industry must champion adoption through case studies, knowledge sharing, and regulatory support. Together, these efforts will ensure grinding aids fulfill their promise of enabling a more efficient, sustainable, and resilient cement manufacturing sector.

References
1. Gao, J., Zhang, S., Wang, X., & Ma, B. (2011). “Effect of organic grinding aids on cement properties and the analysis via liquid chromatography-mass spectrometry.” Construction and Building Materials, 25(8), 3600–3605.
2. Amritphale, S. S., Patel, M., & Singh, R. (2017). “Grinding aids: A study on their mechanism of action in cement grinding processes.” Indian Cement Review.
3. Cembureau – The European Cement Association. “Cement grinding optimisation through grinding aids.” Industry Report, 2023.
4. Flatt, R. J., & Schober, I. (2012). “Superplasticisers and the rheology of concrete.” International Journal of Cement Chemistry, 64(4), 91–109.
5. Mejeoumov, G. G. (2007). “Improved cement quality and grinding efficiency by means of closed mill circuit modeling.” PhD Dissertation, Texas A&M University.
6. Global Cement. “Advances in grinding aids: Market trends and new technologies.” Published October 2024.
7. Statista. “Global grinding aids market size and forecast (2023-2030).” Published March 2024.
8. Pal, B. K., & Rath, P. C. (2020). “Influence of grinding aids on particle size distribution, strength, and hydration of cement.” Journal of Materials Science and Applications, 45(2), 234–246.
9. Indian Cement Review. “Emerging market scope of grinding aids in India.” Published July 2023.
10. Zhang, H., Li, X., & Zhao, Y. (2022). “The role of grinding aids in improving cement hydration kinetics.” Journal of Advanced Materials Science, 17(6), 527–540.
11. Sika AG. “Technical Report on Polycarboxylate Ether (PCE) based grinding aids.” Published 2022.
12. Cement and Concrete Research. “AI-driven optimisation in cement grinding: Case studies and industrial applications.” Volume 152, 2023.
13. Taylor, H. F. W. (1997). Cement Chemistry (2nd Edition). Thomas Telford Publishing.
14. Indian Bureau of Mines (IBM). “Market trends and challenges in cement manufacturing.” Annual Report, 2024.
15. World Cement Association. “Sustainability in grinding aids and cement additives.” Published 2024.

About the author:
Dr SB Hegde, a global cement industry leader with over 30 years of experience, is a Professor at Jain College of Engineering, India, and a Visiting Professor at Pennsylvania State University, USA. Recipient of the ‘Global Visionary’ award, Dr Hegde advises India’s think tank CSTEP on hydrogen usage in cement and consults for major cement companies. He also serves on expert panels of key industry bodies and journals globally.

Efficient bulk material handling has always been critical for seamless production, cost reduction and environmental compliance. Kanika Mathur delves into advanced automation, smart sensors and sustainable transport solutions that are key to overcoming challenges.

The cement industry is a cornerstone of infrastructure development, contributing significantly to economic growth. However, cement production involves the handling and transportation of vast quantities of raw materials such as limestone, clay, iron ore, fly ash and gypsum, as well as the final product—cement itself. Efficient bulk material handling (BMH) systems are crucial in ensuring uninterrupted production, reducing operational costs, minimising material wastage and improving overall efficiency.

In an industry where material losses, dust emissions, and energy consumption are major concerns, advancements in bulk material handling technology are playing a vital role in optimising operations. Automated and energy-efficient bulk handling solutions, such as pneumatic conveying systems, belt conveyors and stacker-reclaimer systems, are transforming the way cement plants manage their raw materials and finished products. This article explores the key aspects of bulk material handling in the cement industry, the latest technological advancements, and the challenges and opportunities in this space.

Importance of bulk material handling
Cement manufacturing requires the continuous movement of raw materials from mines and quarries to processing plants, followed by the transportation of the finished product to storage facilities and distribution networks. Bulk material handling systems ensure that this process runs smoothly, reducing downtime and enhancing productivity.
According to the Global Cement Report (2023), inefficient material handling contributes to 5 – 10 per cent of total cement production losses in India. Additionally, poor handling practices lead to high levels of dust pollution, which is a significant environmental and health concern. With cement production in India expected to reach 500 million metric tonnes by 2025, the demand for advanced and automated material handling systems is increasing rapidly.
Jacob Jose, CEO and Managing Director, Methods India, says, “With our advanced pipe conveyors, downhill conveyors and cross-country conveyors, we have revolutionised the way cement plants transport raw materials. Our technology helps reduce operational costs, minimise environmental impact and improve energy efficiency. Over the years, we have observed a positive impact in the industry, particularly with the growing adoption of pipe conveyors and cross-country conveyors, which have proven to be more efficient and environmentally friendly alternatives to traditional transport methods.”

Key bulk material handling technologies
1. Belt conveyors: The workhorse of cement plants
Belt conveyors are one of the most widely used bulk material handling solutions in the cement industry. They transport raw materials, clinker and finished cement over long distances within the plant and to storage facilities. Modern high-capacity belt conveyors can handle loads exceeding 10,000 tonnes per hour, significantly improving efficiency.

• Advantages: High efficiency, low operational costs, and reduced manual intervention.
• Challenges: Belt wear and tear, spillage, and maintenance requirements.
• Technological advancement: The introduction of heat-resistant and fire-retardant conveyor belts has improved durability, while sensor-based predictive maintenance systems help detect belt failures before they occur.

2. Stacker and reclaimer systems: Optimising storage and retrieval
Stackers and reclaimers are essential for managing bulk raw materials in cement plants. Stackers pile materials such as limestone, coal, and gypsum, while reclaimers retrieve them for processing. These systems ensure homogeneous blending, reducing material variability and enhancing cement quality.

• Latest innovation: Automated stacker and reclaimer systems with AI-driven optimisation help maximise storage space and minimise
  retrieval time.
• Efficiency gains: Newer stacker-reclaimer designs allow for material recovery rates of over 90 per cent, reducing wastage and ensuring a steady feed to the production line.

3. Pneumatic conveying systems: Dust-free material transfer
Pneumatic conveying systems use air pressure or vacuum systems to move powdered and granular materials such as fly ash, cement and kiln dust through pipelines. They are particularly useful in reducing dust emissions and preventing material contamination.

• Advantages: Dust-free operation, reduced environmental impact, and minimal maintenance.
• Industry adoption: Many Indian cement plants are shifting from mechanical conveyors to high-pressure pneumatic conveying systems to comply with pollution control regulations set by the Central Pollution Control Board (CPCB).

4. Screw conveyors and bucket elevators: Compact and versatile solutions

• Screw conveyors: Used for short-distance material movement, particularly for handling fine and powdered materials such as cement, gypsum, and pulverised coal.
• Bucket elevators: Ideal for vertical material transport, commonly used for lifting raw meal, cement, and clinker to storage silos.
• Technological upgrades: The introduction of wear-resistant alloy buckets and variable-speed drives has enhanced the reliability and efficiency of these systems.

Challenges in bulk material handling
Despite significant advancements, several challenges continue to hinder bulk material handling efficiency in cement plants:
1. Material spillage and dust emissions
Material spillage and dust emissions pose environmental, health, and financial challenges. Uncontrolled dust emissions from conveyors, transfer points, and storage facilities not only violate regulatory norms but also lead to material losses. Studies show that up to three per cent of bulk materials are lost due to improper handling in Indian cement plants.

• Solution: Enclosed conveyors, dust suppression systems, and bag filters help reduce dust pollution.

2. High energy consumption
Bulk material handling systems consume a significant amount of energy, especially in large cement plants where materials need to be transported over long distances. According to a CII (Confederation of Indian Industry) report (2023), energy costs account for nearly 40 per cent of total production expenses in cement manufacturing.

• Solution: Energy-efficient conveyor motors, regenerative braking systems, and smart automation can help reduce power consumption.

3. Wear and tear of equipment
Continuous exposure to abrasive materials like limestone and clinker leads to significant wear and tear in bulk material handling equipment, increasing maintenance costs and downtime.

• Solution: The use of wear-resistant liners, ceramic-coated conveyor belts, and automated lubrication systems extends equipment life and reduces maintenance downtime.

4. Logistics and transportation bottlenecks
Moving bulk materials from cement plants to distribution centers requires an efficient logistics network. Rail and road congestion, inadequate infrastructure, and high transportation costs often result in delays and increased operational expenses.

• Solution: Integrated bulk terminals and automated dispatch systems improve supply chain efficiency. The Indian government’s push for multi-modal logistics parks (MMLPs) is expected to enhance cement transportation efficiency.

Indrendra Singh Raghuwanshi, Sales Head – Cement Division, ATS Conveyors, says, “Ensuring that our systems handle diverse alternative fuels reliably is at the core of our engineering approach. Alternative fuels, such as biomass, MSW, RDF and industrial waste vary significantly in terms of composition, size, moisture content, and combustibility. All our systems are designed with flexibility and robustness to meet the unique challenges posed by these fuels while maintaining operational efficiency and safety. Also, before deployment to site, we conduct extensive testing for our equipment to ensure that they can reliably handle alternative fuels under a variety of conditions. This includes testing different fuel types, moisture levels, and feeding rates to identify any potential challenges. Our systems are then fine-tuned during the commissioning phase to ensure optimal performance in real-world conditions.”

The future is automation and digitalisation

The future of bulk material handling in the cement industry lies in automation, artificial intelligence (AI), and digital twin technologies. Leading cement manufacturers are investing in IoT-enabled bulk handling systems that provide real-time monitoring, predictive maintenance, and AI-based process optimisation.

1. Smart sensors and predictive maintenance
AI-powered sensors are now being integrated into conveyors and stackers to detect early signs of wear and tear, enabling proactive maintenance and reducing unplanned downtime.
Nishith Kundar, Co-Managing Partner, Cemtech Engineering Solutions, says, “One of our latest advancements is the introduction of drone inspection technology. Since silos are confined spaces, it is often difficult to assess their internal condition, particularly at the top. We have incorporated drone inspections for both pre-cleaning and post-cleaning assessments. Pre-cleaning drone inspections help us analyse the extent of material buildup, while post-cleaning inspections ensure that the silo has been thoroughly cleaned. This technology is also applicable to pre-heaters, allowing us to monitor internal conditions in confined spaces. By leveraging drone technology, we provide precise and efficient cleaning services, improving safety and operational efficiency.”

2. Digital twin technology
Digital twin models create a virtual replica of bulk handling systems, allowing operators to simulate various scenarios and optimise material flow before implementing changes in real time.

3. Automated Guided Vehicles (AGVs) and robotics
The adoption of AGVs and robotic material handling systems is gaining traction in cement plants for automated raw material transport, warehouse management, and truck loading/unloading.
Gaurav Gautam, Business Unit Head,
Beumer Group, says, “A major recent focus has been integrating digital monitoring tools into our equipment. These tools include condition monitoring sensors that track temperature variations, vibrations and operational anomalies in real-time. By capturing this data, plant operators can take proactive actions when conditions start deviating from normal parameters. This approach prevents sudden breakdowns and, in the long term, enhances the durability and reliability of the equipment.”
“Moving forward, digitalisation will play a key role in tackling wear and tear challenges. By increasing the number of data capture points and applying advanced analytics tools, we can gain deeper insights into equipment health and performance, ensuring a more efficient and predictive maintenance strategy,” he adds.

Conclusion
Efficient bulk material handling is the backbone of cement manufacturing, ensuring a seamless flow of raw materials and finished products while minimising environmental impact and operational costs. As India’s cement industry moves towards higher production capacities and stricter environmental norms, investing in advanced, automated and energy-efficient bulk handling solutions will be key to maintaining competitiveness.
By embracing smart technologies, automation and sustainable handling practices, cement manufacturers can enhance productivity, reduce material losses, and contribute to a greener and more efficient future for the industry.

Accelerating sustainability in the cement industry through alternative fuels and raw materials is key to reducing carbon emissions, optimising resources, and advancing circular economy initiatives. As the industry moves towards a low-carbon future, ICR discusses these critical developments with industry experts.

The cement industry plays a crucial role in infrastructure development and economic growth. However, it is also one of the most carbon-intensive industries, responsible for nearly seven per cent of global CO2 emissions (IEA, 2023). The industry’s heavy reliance on fossil fuels such as coal and petroleum coke, combined with the high emissions from clinker production, has led to growing concerns over its environmental impact.
To address these challenges, cement manufacturers worldwide are increasingly adopting alternative fuels and raw materials (AFR) as part of their sustainability strategies. AFR not only helps in reducing carbon emissions but also supports waste management by utilising industrial by-products and municipal waste. By replacing conventional fuels and raw materials with more sustainable alternatives, the cement industry can significantly lower its environmental footprint while contributing to the circular economy.
Traditional cement manufacturing processes consume large amounts of natural resources, including limestone, clay, and fossil fuels. The production
of one tonne of cement generates approximately 0.9 tonnes of CO2, with the calcination of limestone contributing to 60 per cent of total emissions, while the burning of fossil fuels accounts for the remaining 40 per cent (GCCA, 2023). With global demand for cement expected to rise due to rapid urbanisation and infrastructure expansion, the urgency to adopt low-carbon alternatives has never been greater.
A study by the Global Cement and Concrete Association (GCCA, 2023) highlights that to achieve net-zero emissions by 2050, the cement industry must reduce its carbon footprint by at least 40 per cent by 2030. Alternative fuels and raw materials present a viable pathway to achieving this goal by replacing traditional carbon-intensive inputs with more sustainable and energy-efficient options.

Reducing fossil fuel dependency in cement kilns
Cement kilns operate at extremely high temperatures—often exceeding 1,400°C—making them highly suitable for the incineration of alternative fuels. These high temperatures ensure complete combustion, effectively neutralising pollutants and reducing waste disposal challenges. The most commonly used alternative fuels in cement manufacturing include:

Municipal Solid Waste (MSW) and Refuse-Derived Fuel (RDF)
Municipal solid waste, particularly its non-recyclable components, can be processed into refuse-derived fuel (RDF), which serves as a viable replacement for coal. RDF is composed of materials such as plastics, paper, textiles, and organic waste, which are processed to achieve a high calorific value.
In India, the use of RDF has increased by 12 per cent annually, driven by government initiatives like the Swachh Bharat Mission and the Central Pollution Control Board (CPCB) directives on waste-to-energy projects. Cement plants that integrate RDF in their fuel mix not only reduce reliance on fossil fuels but also contribute to municipal
waste management, preventing large-scale landfill accumulation.

Biomass and agricultural waste
India generates over 500 million tonnes of agricultural waste annually (NITI Aayog, 2022), a significant portion of which goes unutilised or is burned in open fields, contributing to severe air pollution. By leveraging biomass materials such as rice husks, sawdust, coconut shells, sugarcane bagasse, and groundnut shells, cement kilns can replace conventional fuels with carbon-neutral alternatives.
Biomass combustion releases only the CO2 absorbed by plants during their growth cycle, making it an environmentally friendly energy source. Moreover, cement plants using biomass benefit from reduced fuel costs and government incentives for sustainable energy adoption.
Tushar Khandhadia, General Manager – Production, Udaipur Cement Works, says, “Alternative fuels (such as biomass, waste-derived fuels or industrial by-products) often have lower energy content compared to traditional fuels like coal or pet coke. This means that more of the alternative fuel is required to achieve the same level of heat generation. As a result, more fuel needs to be burned, potentially increasing the overall heat consumption of the kiln.”
“Some alternative fuels have higher moisture content or volatile substances, requiring additional energy to evaporate the moisture or combust these volatile compounds. This can lead to a higher heat consumption during the combustion process,”he adds.

Scrap tires and rubber waste
Discarded rubber tires pose a significant waste disposal challenge, with millions accumulating in landfills each year. Cement kilns provide an ideal solution by using shredded tires as an alternative fuel, leveraging their high calorific value, which is comparable to coal. Studies indicate that each ton of scrap tires used in cement kilns can replace approximately 0.7 tonnes of coal, resulting in substantial CO2 emission reductions (CEMBUREAU, 2023).

Industrial and hazardous waste
Cement kilns are also used to incinerate industrial and hazardous waste, including solvents, paint sludge, petrochemical residues and pharmaceutical waste. The extreme temperatures and long residence times in kilns ensure complete combustion, preventing toxic emissions.
India’s Hazardous Waste Management Rules (2016) encourage industries to co-process their waste in cement plants rather than disposing of it in landfills, thus minimising environmental risks while supporting sustainable fuel alternatives.
S Sathish, Partner and National Sector Leader – Industrial Manufacturing, KPMG India, says, “Energy and fuel cost is one of the key costs for cement sector. While a lot of focus has been done on energy consumption optimisation, waste heat recovery areas, buying optimisation of coal and petcoke is a new area, which cement companies are focusing on. Having an AI-based model to optimise the buying cost of fuel, based on petcoke price trends, price trends of coal from different sources, both import and domestic, quality variation analysis of different sources, etc. is a best practice adopted by some leading players to optimise fuel buying. Exploration with green fuels and alternative fuel resources is another big area cement players are working on.”

AFR: A sustainable approach to clinker reduction
The production of clinker, the key ingredient in cement, is highly energy-intensive and generates a significant amount of CO2. By using alternative raw materials (ARMs), manufacturers can reduce their clinker factor, leading to lower emissions and improved resource efficiency.
While replacing fossil fuels like coal and pet coke with alternative fuels can help lower CO2 emissions in the cement industry, the overall reduction is often limited—typically ranging from 1–5 per cent in most cases, with a maximum potential of 18 per cent in select scenarios. The extent of reduction depends largely on the biogenic content of the alternative fuel source. Additionally, certain alternative fuels contain higher levels of sulphur, nitrogen, chlorine, heavy metals and other volatile compounds, which can lead to increased emissions of non-CO2 air pollutants. As a result, maintaining control over emissions—beyond just CO2, including SOX and NOX—has become a key focus. To mitigate these risks, ongoing investments have been necessary as the use of refuse-derived fuel (RDF) continues
to grow.

The most widely used ARMs in cement production include:

Fly ash and bottom ash
Fly ash, a by-product of coal-fired thermal power plants, has gained widespread adoption as a partial clinker substitute. India produces around 226 million tonnes of fly ash annually (CEA, 2023), a substantial portion of which can be utilised in cement production.
Fly ash not only reduces CO2 emissions but also enhances cement properties such as durability, workability, and resistance to sulfate attacks. The Bureau of Indian Standards (BIS) allows up to 35 per cent fly ash in Portland

Pozzolana Cement
(PPC), making it a key component of sustainable cement formulations.

Steel slag and granulated blast furnace slag (GBFS)
The steel industry generates approximately 25 million tonnes of slag annually (Ministry of Steel, 2023). Granulated Blast Furnace Slag (GBFS) is a valuable clinker substitute, with the potential to replace up to 60 per cent of clinker in cement production.
GBFS-based cement exhibits superior strength, durability, and resistance to harsh environmental conditions, making it a preferred choice for infrastructure projects, marine structures, and
road construction.
Olli Hänninen, Owner and Co-founder, Moviator Oy says “The key advantage of using slag today is its ability to reduce CO2 emissions. Cement production relies on four key oxides: calcium oxide, silicon oxide, aluminum oxide and iron oxide—all of which are present in slag. Since slag has already undergone thermal treatment, its use in cement manufacturing requires less energy. As a result, producing cement with slag generates lower CO2 emissions.”

Limestone calcined clay cement (LC3)
Limestone calcined clay cement (LC3) is an innovative low-carbon cement that reduces clinker content by 50 per cent, significantly lowering energy consumption and CO2 emissions. Research conducted by IIT Delhi and EPFL Switzerland suggests that LC3 cement has 25 per cent to 30 per cent lower CO2 emissions compared to Ordinary Portland Cement (OPC) while maintaining comparable strength and performance.

Challenges in large-scale AFR adoption
Despite the significant benefits of AFR, its widespread adoption in India remains limited, accounting for less than 5 per cent of total cement production, compared to 40 per cent in Germany and 60 per cent in the Netherlands (GCCA, 2023). Key challenges include:

Lack of infrastructure for waste collection, sorting, and processing.
Variability in AFR quality, leading to inconsistent combustion efficiency.
Regulatory hurdles in obtaining permits for hazardous waste co-processing.
Limited public awareness about the environmental benefits of AFR.

Strategies for enhancing AFR utilisation
To accelerate the adoption of AFR in India, cement manufacturers must focus on:
1. Developing pre-processing facilities: Establishing regional AFR hubs for waste segregation and processing.
2. Enhancing policy incentives: Government support through tax benefits, subsidies and carbon credits.
3. Industry collaboration: Partnerships between cement companies, municipalities and waste management firms.
4. Advanced emission monitoring: Implementing real-time air quality sensors to ensure compliance with environmental norms.

Andrey Korablin, Founder, SmartScrap, says, “One of the biggest challenges is the human factor. Unfortunately, in many industrial enterprises, people are resistant to change. This is not only because mid-level employees are reluctant to adapt but also due to a lack of proper motivation for using alternative raw materials. In many cases, alternative materials can initially lead to lower productivity or increased energy consumption.”
“These factors directly impact key performance indicators (KPIs) for employees. If using alternative raw materials negatively affects these KPIs, it can also reduce their salaries. Additionally, there is little incentive for employees to seek alternative solutions—if their initiative proves successful, they may receive no financial reward. However, if they make a mistake, they could be demotivated or even risk losing their jobs. This is why, at the top management level, it is crucial to create a system of motivation and a company culture that encourages change and innovation,”
he adds.

Conclusion
The integration of alternative fuels and raw materials is essential for the cement industry’s transition towards low-carbon and sustainable manufacturing practices. By replacing fossil fuels and traditional raw materials with eco-friendly alternatives, the industry can significantly reduce emissions, lower energy consumption, and contribute to a circular economy. With the right policies, technological advancements, and industry collaboration, AFR adoption in India can scale up, paving the way for a more sustainable and resilient cement sector.

– Kanika Mathur