Concrete

SCMs encourage closed-loop systems

Published

1 year ago

November 22, 2024

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As the cement industry prioritises sustainability and performance, Supplementary Cementitious Materials (SCMs) are redefining standards, explains Tushar Khandhadia, General Manager – Production, Udaipur Cement Works.

What role do supplementary cementitious materials (SCMs) play in enhancing the performance and sustainability of cement and concrete?
SCMs play a crucial role in enhancing the performance and sustainability of cement and concrete. These materials are added to concrete to improve its properties such as strength, durability, and workability, as well as to reduce the environmental impact of cement production. The addition of SCMs to cement reduces the amount of Portland cement required to manufacture concrete, reducing the carbon footprint of the concrete. These materials are often industrial waste products or by-products that can be used as a replacement for cement, such as fly ash, slag and silica fume.
SCMs also reduce the amount of water required to produce concrete, which reduces the environmental impact of concrete production. This is achieved through their ability to improve the workability of concrete, allowing the same amount of work to be done with less water.
In addition, SCMs improve the durability of concrete by reducing the risk of cracking and improving resistance to chemical attack and other forms of degradation.

How has your company integrated SCMs into its production process, and what challenges have you encountered?
The integration of SCMs into cement and concrete production may pose certain challenges in the areas of sourcing, handling and production optimisation.

Sourcing: Finding an adequate and reliable supply of SCMs can be a challenge. Some SCMs, such as fly ash and slag, are readily available by-products of other industrial processes, while others such as silica fume or metakaolin may be more difficult to source.
Handling: The storage, handling, and transportation of SCMs require special considerations due to their physical and chemical properties. For instance, some SCMs are stored in moist conditions to prevent them from drying out and becoming airborne, which could pose a safety risk to workers.
Production optimisation: The addition of SCMs into the mix may require adjustments to the production process to achieve the desired properties of cement and concrete. For example, the use of SCMs may affect the setting time, workability, strength gain, and other properties of the final product, which may require reconfiguration of the production process.
Quality control: The addition of SCMs may introduce variability in the properties of cement and concrete, and rigorous quality control measures are necessary to ensure the final product meets the required specifications and standards.

Proper planning, handling and production optimisation are essential in overcoming the challenges encountered during the integration process.

Can you share insights on how SCMs such as fly ash, slag and silica fume impact the durability and strength of concrete in different environmental conditions?

Fly ash is a by-product of coal combustion and is widely used as an SCM in the production of concrete. When added to concrete, fly ash reacts with the calcium hydroxide present in the concrete to form additional cementitious materials, resulting in improved strength and durability. Fly ash increases the durability of concrete by improving its resistance to sulphate and acid attacks, reducing shrinkage and decreasing the permeability of concrete. Fly ash also enhances the workability and pumpability of concrete while reducing the heat of hydration, which reduces the risk of thermal cracking. In cold climates, fly ash helps to reduce the risk of freeze-thaw damage.
Slag is a by-product of steel production and is used as an SCM because of its high silica and alumina content. When added to concrete, slag reacts with the calcium hydroxide present in the concrete to form additional cementitious materials, resulting in improved strength and durability. Slag increases the durability of concrete by improving its resistance to sulphate and acid attacks, reducing shrinkage and improving the strength of concrete over time. Slag also enhances the workability of concrete, reduces the heat of hydration, and improves the resistance of concrete to chloride penetration.
Silica fume is a by-product of the production of silicon and ferrosilicon alloys and is used as an SCM because of its high silica content. When added to concrete, silica fumes react with the calcium hydroxide present in the concrete to form additional cementitious materials, resulting in improved strength and durability. Silica fume increases the durability of concrete by improving its resistance to sulphate and acid attacks, reducing permeability, and improving abrasion resistance. Silica fume also enhances the workability of concrete, reduces the heat of hydration, and improves the resistance of concrete to chloride penetration.

Overall, the use of SCMs such as fly ash, slag and silica fume can significantly improve the durability and strength of concrete in different environmental conditions. Their impact on concrete varies depending on the availability, physical and chemical properties of the specific SCM being used and proper testing and engineering analysis should be done for each mix design in order to optimise the final product.

With the global push for sustainability, how do SCMs contribute to reducing the carbon footprint of cement production?
SCMs provide an environmentally friendly alternative to traditional Portland cement by reducing the amount of clinker required to produce cement. Clinker is the main ingredient in Portland cement and is produced by heating limestone and other raw materials to high temperatures, which releases significant GHG emissions. Thus, by using SCMs, less clinker is required, thereby reducing GHG emissions, energy use and the environmental impact of cement production. Some SCMs such as fly ash and slag are by-products of other industrial processes, meaning that their use in cement production reduces waste and enhances resource efficiency. Moreover, the use of SCMs can enhance the properties of concrete, thereby increasing its durability and service life which helps to further reduce the overall embodied carbon of the structure.
In short, the use of SCMs contributes to reducing the carbon footprint of cement production by improving the efficiency of resource utilisation and reducing greenhouse gas (GHG) emissions during the production process. This has led to an increased demand for SCMs in the construction industry, as environmental concerns and sustainable development goals have become more prominent factors in the selection of building materials.

What strategies or innovations has your company adopted to ensure a consistent and reliable supply of SCMs, given their reliance on industrial by-products?

Developing partnerships with suppliers: Many cement and concrete manufacturers establish long-term partnerships with suppliers of SCMs. These partnerships provide a reliable supply of high-quality SCMs, improve supply chain efficiency, and often provide access to new sources of SCMs.
Advanced SCM processing techniques: Many companies are investing in advanced processing techniques to unlock new sources of high-quality SCMs. Advanced processing techniques include new separation processes, calcination techniques, and chemical activation methods.
Alternative SCM sources: Many companies are exploring alternative SCM sources to supplement or replace traditional SCMs. Examples include agricultural by-products such as rice hull ash or sugar cane bagasse ash, which can be used in place of fly ash.
Quality control measures: Strict quality control measures are necessary to ensure consistent quality of SCMs. Many companies use advanced testing methods, such as particle size analysis, chemical analysis, and performance testing, to validate the quality of SCM materials used in production.
Supply chain diversification: Diversifying suppliers and SCM sources is another way to ensure a reliable supply. This reduces the risk of supply chain disruptions caused by factors such as natural disasters, market changes, or geopolitical risks.

The strategies and innovations adopted to ensure a consistent and reliable supply of SCMs include establishing long-term partnerships with suppliers, investing in advanced processing techniques, exploring alternative SCM sources, implementing strict quality control measures, and diversifying supply chains. By implementing these approaches, we ensure that use of SCMs in cement production is an effective and viable solution for reducing the environmental impact of operations

How does the use of SCMs align with your company’s broader goals around circular economy and resource efficiency?
Here are some ways in which the use of SCMs supports these goals:

Reducing waste: The use of SCMs, such as fly ash and slag, diverts significant quantities of industrial waste from landfills, turning it into a valuable resource that can be used in construction. This helps to reduce waste and conserve natural resources.
Reducing carbon emissions: Cement production is a significant contributor to greenhouse gas emissions, and the use of SCMs can significantly reduce the amount of cement required in concrete mixtures. This helps to reduce the carbon footprint of construction activities and move towards a low-carbon economy.
Enhancing resource efficiency: The use of SCMs can reduce the demand for raw materials, energy, and water in the production of concrete. This not only conserves natural resources but also reduces the costs associated with the extraction, transportation and processing of these materials.
Closing the loop: SCMs encourage closed-loop systems in the construction sector, where waste materials from one process become input materials for another. This can improve the efficiency and sustainability of the construction industry.
Supporting sustainable design practices: The use of SCMs can support sustainable design practices by improving the durability and performance of structures while also reducing their environmental impact. This supports a circular approach to design, construction and operation of buildings and infrastructure
that improves their social, economic and environmental sustainability.

What future trends or developments do you foresee in the use of SCMs within the cement industry?
Future trends in the use of SCMs within the cement industry are likely to focus on: increased utilisation of diverse waste-derived SCMs, development of new SCM sources to address potential shortages, advanced characterisation techniques to optimise SCM blends and data-driven approaches to predict and optimise SCM usage for reduced carbon footprint and improved concrete performance; all driven by the growing need for sustainable cement production and stricter environmental regulations.
Key aspects of this trend include:

Expanding SCM sources: Exploring a wider range of industrial byproducts and waste materials like recycled concrete aggregate, activated clays and certain types of industrial minerals as potential SCMs to reduce reliance on traditional sources like fly ash, which may become increasingly limited.
Advanced material characterisation: Utilising sophisticated techniques to better understand the chemical and physical properties of SCMs, allowing for more precise blending and optimisation of their use in cement mixtures.
Data-driven decision making: Implementing machine learning and big data analysis to predict the performance of different SCM combinations, allowing for real-time adjustments in cement production based on available SCM sources and desired concrete properties.
Focus on local sourcing: Prioritising the use of locally available SCMs to reduce transportation costs and environmental impact.
Development of new SCM processing techniques: Research into methods to enhance the reactivity and performance of less readily usable SCMs through processes like activation or modification.
Life cycle analysis (LCA) integration: Using LCA to assess the full environmental impact of different SCMs and optimise their use to minimise carbon emissions throughout the cement production process.
Regulatory frameworks and standards:Increased adoption of building codes and industry standards that promote the use of SCMs and set targets for reduced carbon emissions in cement production.

– Kanika Mathur

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Concrete

Dalmia Bharat launches Weather 365 in East India

New water-repellent cement targets weather-resilient housing demand

Published

2 hours ago

May 15, 2026

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Dalmia Bharat Cement has launched Weather 365, a super-premium water-repellent cement brand for retail markets in West Bengal and Bihar. The product is designed to address rising demand for durable and weather-resistant construction materials in Eastern India.

Weather 365 offers protection against seepage, dampness and moisture damage, especially in regions exposed to heavy rainfall, humidity and changing weather cycles. The cement is suited for roofs, columns and foundations, and uses uniform water-repellent technology to reduce water penetration, steel corrosion, efflorescence and damp patches.

The company said the product will be available in water-resistant and tamper-proof BOPP packaging. It will also provide on-site technical support through engineering and technical services teams to guide customers on construction practices and long-term building performance.

Positioned in Dalmia Bharat Cement’s premium portfolio, Weather 365 targets homeowners, contractors and builders seeking stronger concrete, improved paint life and better structural durability. The launch supports the company’s strategy to expand premium construction solutions in key Eastern India markets.

Concrete

Filtration Technology is Critical for Efficient Logistics

Published

4 hours ago

May 15, 2026

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Niranjan Kirloskar, MD, Fleetguard Filters, makes the case that filtration technology, which has been long treated as a routine consumable, is in fact a strategic performance enabler across every stage of cement production and logistics.

India’s cement industry forms the core for infrastructure growth of the country. With an expected compound annual growth rate of six to eight per cent, India has secured its position as the second-largest cement producer globally. This growth is a result of the increasing demand across, resulting in capacity expansion. Consequently, cement manufacturers are now also focusing on running the factories as efficiently as possible to stay competitive and profitable.
While a large portion of focus still remains on production technologies and capacity utilisation, the hidden factor in profitability is the efficiency of cement logistics. The logistics alone account for nearly 30 per cent to 40 per cent of the total cost of cement, making efficiency in this segment a key lever for profitability and reliability.
In the midst of this complex and high-intensity ecosystem, filtration often remains one of the most underappreciated yet essential enablers of performance.

A demanding operational landscape
Cement production and logistics inherently operate in some of the harshest industrial environments. With processes such as quarrying, crushing, grinding, clinker production, and bulk material handling expose the machinery to constant high temperatures, heavy loads, and dust, often the silent destructive force for engines.
The ecosystem is abrasive, and often one with a high contamination index. These challenging conditions demand equipment such as the excavators, crushers, compressors, and transport vehicles to perform and perform efficiently. The continuous exposure to contamination across every aspect like air, fuel, lubrication, and even hydraulic systems causes long-term damage. Studies have also shown that 70 to 80 per cent of hydraulic system failures are directly linked to contamination, while primary cause of engine wear is inadequate air filtration.
For engines as heavy as these, even a minor contaminant has a cascading effect; reducing efficiency, performance and culminating to unplanned downtime. Particles as small as 5 to 10 microns, far smaller than a human hair (~70 microns), can cause significant damage to critical engine components. In an industry where margins are closely linked to operational efficiency, such disruptions can significantly affect both cost structures and delivery timelines.

Dust management: A persistent challenge
Dust is a natural by-product in cement operations. From drilling and blasting in the quarries to packing in plants, this fine particulate matter does occupy a large space in operations. Dust concentration levels in quarry and crushing zones often create extremely high particulate exposure for equipment. These fine particles, when enter the engines and critical systems, accelerates the wear and tear of the component, affecting directly the operational efficiency. Over time every block fall; engine performance declines, fuel consumption rises, and maintenance cycles shorten. In this case, effective air filtration is the natural first line of defence. Advanced filtration systems are designed to capture high volumes of particulate matter while maintaining consistent airflow, ensuring that engines and equipment operate under optimal conditions.
In high-dust applications, as in cement production, even the filtration systems are expected to sustain performance over extended periods without the need of frequent replacement. This becomes crucial in remote quarry locations where access to frequent maintenance may be limited.

Fluid cleanliness and system integrity
Beyond air filtration, fluid systems also play a crucial role for equipment reliability in cement operations. Fuel systems are required to remain free from contaminants for efficient working of combustion and injection protection. Additionally, lubrication systems also need to maintain the oil purity to reduce friction and prevent any premature wear of moving parts. The hydraulic systems, which are key to several heavy equipment operations, are especially sensitive to contamination.
If fine particles or water enters these systems, it can lead to reduced efficiency, erratic performance, and eventual failure of the system. Modern filtration systems are designed with high-efficiency media capable of removing extremely fine contaminants, with advanced fuel and oil filtration solutions filtering particles as small as two to five microns. Multi-stage filtration systems further ensure that fluid performance is maintained even under challenging operating conditions.
Another critical aspect of fuel systems is water separation. Removing moisture helps prevent corrosion, improves combustion efficiency and enhances overall engine reliability. Modern water separation technologies can achieve over 95 per cent efficiency in removing water from fuel systems.

Ensuring reliability across the value chain
Filtration plays a critical role across every stage of cement logistics:
• Quarry operations: Equipment operates in highly abrasive environments, requiring strong protection against dust ingress and hydraulic contamination.
• Processing units: Crushers, kilns, and grinding mills depend on clean lubrication and cooling systems to sustain continuous operations.
• Material handling systems: Pneumatic and mechanical systems rely on clean air and fluid systems for efficiency and reliability.
• Transportation networks: Bulk carriers and trucks must maintain engine health and fuel efficiency to ensure timely deliveries.
Across these operations, filtration plays a vital role; as it supports consistent equipment performance while reducing the risk of unexpected failures.
Effective filtration solutions can reduce unscheduled equipment failures by 30 to 50 per cent across heavy-duty operations.

Uptime as a strategic imperative
In cement manufacturing, uptime is currency. Downtime not only delays the production, but it also greatly impacts the supply commitments and logistics planning. With the right filtration systems, contaminants are kept at bay from entering the
critical systems, and they also significantly extend the service intervals.
Optimised filtration can extend service intervals by 20 to 40 per cent, reducing maintenance frequency while maintaining consistent performance across demanding operating conditions. Filtration systems designed for heavy-duty applications sustain efficiency throughout their lifecycle, ensuring reliable protection with minimal interruptions. This leads to improved equipment availability, lower maintenance costs, and more predictable operations, with well-maintained systems capable of achieving uptime levels of over 90 to 95 per cent in challenging cement environments.

Supporting emission and sustainability goals
With the rising environmental awareness, the cement industry too is aligning with the stricter norms and sustainability targets. In this scenario, the operational efficiency is directly linked to emission control.

Air and fuel systems that are clean enable
much more efficient combustion. They also reduce emissions from both the stationary equipment and transport fleets. Similarly, with a well-maintained fluid cleanliness, emission systems function better. Poor combustion due to contamination can increase emissions by 5 to 10 per cent, making clean systems critical for compliance.
Additionally, efficient and longer lasting filtration systems significantly reduce any waste generation and contribute to increased sustainable maintenance practices. Extended-life filtration solutions can reduce filter disposal and maintenance waste by 15 to 20 per cent. Smart and efficient filtration in this case plays an important role in meeting the both regulatory and environmental objectives within the industry.

Advancements in filtration technology
Over the years, there has been a significant evolution in the filtration technology to meet the modern industrial applications.
Key developments include:
• High-efficiency filtration media capable of capturing very fine particles without restricting flow
• Compact and integrated designs that combine multiple filtration functions
• Extended service life solutions that reduce replacement frequency and maintenance downtime
• Application-specific engineering tailored to different stages of cement operations
Modern multi-layer filtration media can improve dust-holding capacity by up to two to three times compared to conventional systems, while maintaining consistent performance. These advancements have transformed filtration from a basic maintenance component into a critical performance system.

Adapting to diverse operating conditions
The cement industry of India operates across diverse geographies. Spanning across regions with arid regions with higher dust levels, to the coastal areas with higher humidity, challenges of each region pose different threats to the engines. Modern filtration systems are thus tailored to address these unique challenges of each region.
Indian operating environments often range from 0°C to over 50°C, with some of the highest dust loads globally in mining zones.
Additionally, filtration technology can also be customised to variations which then align the system design with factors like dust load, temperature, and equipment usage patterns. Equipment utilisation levels in India are typically higher than global averages, making robust filtration even more critical. This approach ensures optimal performance and durability across different operational contexts.

Impact on total cost of ownership
Filtration has a direct and measurable impact on the total cost of ownership of equipment.
Effective filtration leads to:
• Lower wear and tear on critical components
• Reduced maintenance and repair costs
• Improved fuel efficiency
• Extended equipment life
• Higher operational uptime
Effective filtration can extend engine life by 20 to 30 per cent and reduce overall maintenance costs by 15 to 25 per cent over the equipment lifecycle. These benefits collectively enhance productivity and reduce lifecycle costs. Conversely, inadequate filtration can result in frequent breakdowns, increased maintenance expenditure, and reduced asset utilisation.

Building a more efficient cement ecosystem
With the rising demand across various sectors, the cement industry is expected to expand at an unprecedented rate. This growth is forcing the production to move towards a more efficient and resilient system of operations. This requires attention not only to production technologies but also to the supporting systems that enable consistent performance. Filtration must be viewed as a strategic investment rather than a routine consumable. By ensuring the cleanliness of air and fluids across systems, it supports reliability, efficiency, and sustainability.

The road ahead
The future of cement logistics will be shaped by increasing mechanisation, digital monitoring, and stricter environmental standards. The industry is also witnessing a shift towards predictive maintenance and condition monitoring, where filtration performance is increasingly integrated with real-time equipment diagnostics.
In this evolving landscape, the role of filtration will become even more critical. As equipment becomes more advanced and operating conditions more demanding, the need for precise contamination control will continue to grow. From quarry to construction site, filtration technology underpins the performance of every critical system. It enables equipment to operate efficiently, reduces operational risks, and supports the industry’s broader goals of growth and sustainability. In many ways, it is the unseen force that keeps the cement ecosystem moving, quietly ensuring that every link in the value chain performs as expected.

About the author
Niranjan Kirloskar, Managing Director, Fleetguard Filters, is focused on driving innovation, operational excellence, and long-term business growth through strategic and people-centric leadership. With a strong foundation in ethics and forward-thinking decision-making, he champions a culture of collaboration, accountability, and technological advancement.

Concrete

Cement’s Next Fuel Shift

Published

6 hours ago

May 15, 2026

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Jignesh Kindaria highlights how Thermal Substitution Rate (TSR) is emerging as a critical lever for cost savings, decarbonisation and competitive advantage in the cement industry.

India is simultaneously grappling with two crises: a mounting waste emergency and an urgent need to decarbonise its most carbon-intensive industries. The cement sector, the second-largest in the world and the backbone of the nation’s infrastructure ambitions, sits at the centre of both. It consumes enormous quantities of fossil fuel, and it has the technical capacity to consume something else entirely: the waste our cities cannot get rid of.
According to CPCB and NITI Aayog projections, India generates approximately 62.4 million tonnes of municipal solid waste annually, with that figure expected to reach 165 million tonnes by 2030. Much of this waste is energy-rich and non-recyclable. At the same time, cement kilns operate at material temperatures of approximately 1,450 degrees Celsius, with gas temperatures reaching 2,000 degrees. This high-temperature environment is ideal for co-processing, ensuring the complete thermal destruction of organic compounds without generating toxic residues. The physics are in our favour. The infrastructure is not.
Pre-processing is not the support act for co-processing. It is the main event. Get the particle size wrong, get the moisture wrong, get the calorific value wrong and your kiln thermal stability will suffer the consequences.

The regulatory push is real
The Solid Waste Management (SWM) Rules 2026 mandate that cement plants progressively replace solid fossil fuels with Refuse-Derived Fuel (RDF), starting at a 5 per cent baseline and scaling to 15 per cent within six years. NITI Aayog’s 2026 Roadmap for Cement Sector Decarbonisation targets 20 to 25 per cent Thermal Substitution Rate (TSR) by 2030. Beyond compliance, every tonne of coal replaced by RDF generates measurable carbon reductions which is monetisable under India’s emerging Carbon Credit Trading Scheme (CCTS). TSR is no longer a sustainability metric. It is a financial lever.
Yet our own field assessments across multiple Indian cement plants reveal a sobering reality: the primary barrier to scaling AFR adoption is not waste availability. It is the fragmented and under-engineered pre-processing ecosystem that sits between the waste and the kiln.

Why Indian waste is a different engineering problem
Indian municipal solid waste is not the material that imported shredding equipment was designed for. Our waste streams frequently exceed 40 per cent to 50 per cent moisture content, particularly during monsoon cycles, saturated with abrasive inerts including sand, glass, and stone. Plants relying on imported OEM equipment face months of downtime awaiting proprietary spare parts. Machines built for segregated, low-moisture waste fail quickly and disrupt the entire pre-processing operation in Indian conditions.
The two most common failures we observe are what I call the biting teeth problem and the chewing teeth problem. Plants relying solely on a primary shredder reduce bulk waste to large fractions, but the output remains too coarse for stable kiln combustion. Others attempt to use a secondary shredder as a standalone unit without a primary stage to pre-size the feed, leading to catastrophic mechanical failure. When both stages are present but mismatched in throughput capacity, the system becomes a bottleneck. Achieving the 40 to 70 tonnes per hour required for meaningful coal displacement demands a precisely coordinated two-stage process.

Engineering a made-in-India answer
At Fornnax, our response to these challenges is grounded in one principle: Indian waste demands Indian engineering. Our systems are built around feedstock homogeneity, the holy grail of kiln stability. Consistent particle size and predictable calorific value are the foundation of stable kiln combustion. Without them, no TSR target is achievable at scale.
Our SR-MAX2500 Dual Shaft Primary Shredder (Hydraulic Drive) processes raw, baled, or loosely mixed MSW, C&I waste, bulky waste, and plastics, reducing them to approximately 150 mm fractions at throughputs of up to 40 tonnes per hour. The R-MAX 3300 Single Shaft Secondary Shredder (Hydraulic Drive), introduced in 2025, takes that primary output and produces RDF fractions in the 30 to 80 mm range at up to 30 tonnes per hour, specifically optimised for consistent kiln feeding. We have also introduced electric drive configurations under the SR-100 HD series, with capacities between 5 and 40 tonnes per hour, already operational at a leading Indian waste-processing facility.
Looking ahead, Fornnax is expanding its portfolio with the upcoming SR-MAX3600 Hydraulic Drive primary shredder at up to 70 tonnes per hour and the R-MAX2100 Hydraulic drive secondary shredder at up to 20 tonnes per hour, designed specifically for the large-scale throughput that higher TSR ambitions require.

The investment case is now
The 2070 Net-Zero target is not a distant goal for India’s cement sector. It starts today, with decisions being made on the plant floor.
The SWM Rules 2026 are already in effect, requiring cement plants to replace coal with RDF. Carbon credit markets are opening up, and coal prices are not going to get cheaper. Every tonne of coal a cement plant replaces with waste-derived fuel saves money on one side and generates carbon credit revenue on the other. Pre-processing infrastructure is no longer just a compliance requirement. It is a business investment with a measurable return.
The good news is that nothing is missing. The technology works. The waste is available in every Indian city. The government has provided the policy direction. The only thing standing between where the industry is today and where it needs to be is the commitment to build the right infrastructure.
The cement companies that move now will not just meet the regulations. They will be ahead of every competitor that waits.

About the author
Jignesh Kundaria is the Director and CEO of Fornnax Technology. Over an experience spanning more than two decades in the recycling industry, he has established himself as one of India’s foremost voices on waste-to-fuel technology and alternative fuel infrastructure.