Economy & Market
AFRs: Cutting Carbon Emissions
Published
4 months agoon
By
Roshna
Ulhas Parlikar, Director MRAI and Global Consultant, recommends harnessing India’s vast waste potential. The cement industry can dramatically cut carbon emissions through advanced co-processing of alternative fuels and raw materials (AFRs).
Indian cement plants emitted approximately 177 million tonnes of CO2 in 2023, representing about 6 per cent of the country’s total fossil and industrial emissions. These emissions result primarily from the calcination of limestone (about 56 per cent), combustion of fuels for process heat (about 32 per cent) and about 12 per cent is from the electricity used in the manufacturing process. The sector’s total emissions are rising due to increased cement demand to meet rapid urbanisation and infrastructure needs. Without policy interventions to reduce the emissions, they are projected to rise significantly with the demand projections of the cement of the future.
There are following five major initiatives
feasible for reducing the carbon emissions from the cement manufacture.
1. Reducing energy consumption and use of waste heat recovery processes
2. Reducing clinker content
3. Use of alternative fuels and raw materials (AFRs)
4. Carbon capture, use and storage (CCUS)
5. Developing low carbon cements, novel binders etc.
The first three options are immediately feasible to be implemented for carbon emission reduction by the Indian cement industry and among them the use of AFRs offers a huge opportunity. This is because the Thermal Substitution Rate (TSR) of Indian cement industry is only at a level of about 7-8 per cent as at present and is easily feasible to be increased to >80 per cent with the availability of large quantum of untreated waste in the country and is already established as feasible in some of the countries.
With the available policy support, the Indian cement plants can easily leverage use of AFRs as a feasible local and sustainable solution for the management of wastes. This initiative of use of wastes as AFRs provides a great opportunity to the Indian cement industry to contribute to targets set by themselves to comply to the India’s commitment to reach net-zero by 2070.
Use of waste materials as AFRs
Use of waste as AFRs requires the waste materials to be converted into AFRs by pre-processing. The technology of utilising these waste materials as AFRs is called as co-processing. The Indian cement plants are advancing co-processing technology by using industrial, agricultural and municipal wastes as AFRs.
The key AFR sources in India include:
- Refuse-derived fuel (RDF): Made from urban municipal waste diverted away from landfill and fresh waste.
- Biomass: Crop residues such as rice husk, bagasse, coconut shells, and other regionally abundant wastes and also the harvest residues, field leftovers, rejects from the food and agro processing industries, forest felling and dry leaves, etc.
- Industrial by-products: Hazardous and non-hazardous waste from pharmaceuticals,chemical, automobile, refinery and other manufacturing sectors.
- Waste plastics that is non-recyclable.
AFR co-processing strategy
The co-processing strategy of AFRs in India supports national waste management goals such as reducing landfill, incineration of hazardous and municipal wastes, and enabling safe resource recovery. Cement kilns are uniquely positioned to help address the country’s growing urban and industrial waste challenge, aligning climate goals and circular economy priorities.
Many plants manufacturing clinker in India that belong to Adani Group, UltraTech, Dalmia, Shree, JK, JK Lakshmi, Nuvoco Vista, Vicat, Heidelberg, Ramco, KCP, Nagarjuna, Chettinad and others are operating at a reasonable scale of AFR utilisation. Some of these plants have even achieved a TSR level of more than 35 per cent. Some of these cement plants that have reached the higher levels of chlorine have also set up the chlorine by-pass systems.
Barriers in use of waste materials
While cement units strive towards their target thermal substitution rate (TSR), they face following logistical and technical barriers.
- Consistency in the quality of the input waste materials
- Higher levels of moisture
- Appropriate facilities to handle and processing them efficiently
- Appropriate facilities to feed AFRs in a consistent manner to achieve stability in the kiln operations.
- Innovations in achieving improved calciner and feed chute design for efficient combustion.
- Innovations to deal with the inefficient combustion of AFRs experienced in the kiln system.
- Availability of only marginal grade limestone in most of the clusters manufacturing cement.
- Advanced innovations to deal with the coatings experienced kiln process due to chlorine, alkalis and sulphur.
- Unavailability of the personnel that are equipped with the science and technology knowledge associated with the pre-processing and co-processing operations.
- Lack of opportunity to improve the skill levels of the operating personnel associated with the pre-processing and co-processing of AFRs.
Indian policy instruments and national programmes
The Indian policy instruments such as the Perform, Achieve, Trade (PAT) scheme and Extended Producer Responsibility (EPR) have accelerated the efforts towards improving the energy efficiency, AFR co-processing and waste heat recovery within Indian cement plants. Other national programmes such as Swatch Bharat Abhiyan, Mission Samarth and Carbon Emission Trading scheme are also expected to contribute this drive of increasing AFR utilisation in the clinker manufacture by way of bringing more and more waste material in the market place.
To facilitate the desired level of growth in the co-processing initiative in India, following measures are desired.
- Characterisation of the region-specific wastes along with their inventory.
- Investment in pre-processing facilities by the waste management agency to produce uniform quality AFRs from waste materials having diverse level of characteristics.
- Investment in the co-processing infrastructure to feed higher level of AFRs with consistent flow rates in the calciners, kiln inlet and main burners of the cement plant.
- Standardisation and certification to assure quality of AFRs.
- Appropriate intervention related to artificial intelligence, machine learning and block chain technologies and other technologies in the kiln process to achieve process stability.
- Cross-industry partnerships for waste stream security.
- Community awareness and local government participation are essential for robust waste supply chains.
Improving good quality waste streams
RDF from municipal source and biomass from agricultural sectors are the two waste streams that get generated in large volumes and are available for use by the cement industry in India. To harness the use potential of these large quantum waste streams and gainfully co-process them in the cement kilns following are the proposed recommendations.
- Raise awareness across municipalities and farmers about co-processing benefits.
- Incentivise and accelerate the investments in waste sorting, transportation, and pre-processing infrastructure.
- Encourage collaboration between cement companies, regulators, city authorities, waste management agencies, farmers and research institutions.
- Mandate the inclusion of the production of RDF meeting Grade 1, Grade 2 and Grade 3 in the DPR & RFQ of the treatment projects of the municipalities that are being implemented for the management of fresh MSW and also MSW from dump yards.
- Mandate the use of leftover biomass from the fields as well as from the food and agro processing industries as AFR in the power plants and cement plants through suitable incentive schemes.
- To promote use of biomass being secured under mission Samarth for use in cement industry, too.
Key success factors
Following are the key factors that facilitate successful co-processing with smooth kiln operation. These need to be respected critically.
- Securing consistent quality and quantity of segregated waste for pre-processing into AFRs.
- Continuous technology improvement (handling, blending, emissions monitoring) to achieve processed AFR having consistent quality that is aligned with the raw mix and fuel mix design.
- Strong partnerships with waste processors with win-win, adaptable and operable business models.
- Adaptable infrastructure to deal with the variable waste feeds, higher TSR and regulatory changes.
Equipment for co-processing
For achieving successful co-processing of AFRs, cement plant needs following well designed equipment and facilities.
- Environmentally sound waste receiving and storage systems (open and covered) with impervious floor, leachate management and fire-fighting systems for different kinds of waste materials.
- Pre-processing equipment consisting of shredders, dryers, screens, metal separators etc to homogenise AF feed and achieve desired level of standard deviation in its quality.
- AFR co-processing equipment consisting of appropriately designed feeding, weighing and dosing systems with control instrumentation that feed the AFR at each entry pint of the kiln system with consistent rate with defined accuracy levels.
- Appropriate fire-fighting system for the protection of the preprocessing and coprocessing facilities.
Kiln burner with required upgrades and momentum to permit efficient combustion of the AFRs. - Automated process control and emissions monitoring with required sensors and AI interventions for smooth process operation.
- Laboratory facility to monitor and control the AFR quality, its consistency, impact of AFR and its heavy metals, chlorine and sulphur content on the process, environment and clinker product etc.
Conclusion
By aggressively pursuing alternative fuels and raw materials, Indian cement plants can leverage their geographic, industrial and policy strengths, rapidly cutting carbon intensity while solving waste challenges and supporting sustainable growth. Leading companies are already pioneering these transitions; the sector’s future lies in scaling these solutions, investing in technical innovation, and collaborating widely with different stakeholders to fulfil India’s climate commitments and infrastructural ambitions.
ABOUT THE AUTHOR:
Ulhas Parlikar, Director MRAI and Global Consultant, served on numerous national and international committees leading initiatives in waste management, AFR utilisation, and sustainable practices.
SEEPEX introduces BN pumps with Smart Joint Access (SJA) to improve efficiency, reliability, and inspection speed in demanding rock blasting operations.
Designed for abrasive and chemical media, the solution supports precise dosing, reduced downtime, and enhanced operational safety.
SEEPEX has introduced BN pumps with Smart Joint Access (SJA), engineered for the reliable and precise transfer of abrasive, corrosive, and chemical media in mining and construction. Designed for rock blasting, the pump features a large inspection opening for quick joint checks, a compact footprint for mobile or skid-mounted installations, and flexible drive and material options for consistent performance and uptime.

“Operators can inspect joints quickly and rely on precise pumping of shear-sensitive and abrasive emulsions,” said Magalie Levray, Global Business Development Manager Mining at SEEPEX. “This is particularly critical in rock blasting, where every borehole counts for productivity.” Industry Context
Rock blasting is essential for extracting hard rock and shaping safe excavation profiles in mining and construction. Accurate and consistent loading of explosive emulsions ensures controlled fragmentation, protects personnel, and maximizes productivity. Even minor deviations in pumping can cause delays or reduce product quality. BN pumps with SJA support routine maintenance and pre-operation checks by allowing fast verification of joint integrity, enabling more efficient operations.
Always Inspection Ready
Smart Joint Access is designed for inspection-friendly operations. The large inspection opening in the suction housing provides direct access to both joints, enabling rapid pre-operation checks while maintaining high operational reliability. Technicians can assess joint condition quickly, supporting continuous, reliable operation.
Key Features
- Compact Footprint: Fits truck-mounted mobile units, skid-mounted systems, and factory installations.
- Flexible Drive Options: Compact hydraulic drive or electric drive configurations.
- Hydraulic Efficiency: Low-displacement design reduces oil requirements and supports low total cost of ownership.
- Equal Wall Stator Design: Ensures high-pressure performance in a compact footprint.
- Material Flexibility: Stainless steel or steel housings, chrome-plated rotors, and stators in NBR, EPDM, or FKM.
Operators benefit from shorter inspection cycles, reliable dosing, seamless integration, and fast delivery through framework agreements, helping to maintain uptime in critical rock blasting processes.
Applications – Optimized for Rock Blasting
BN pumps with SJA are designed for mining, tunneling, quarrying, civil works, dam construction, and other sectors requiring precise handling of abrasive or chemical media. They provide robust performance while enabling fast, reliable inspection and maintenance.With SJA, operators can quickly access both joints without disassembly, ensuring emulsions are transferred accurately and consistently. This reduces downtime, preserves product integrity, and supports uniform dosing across multiple bore holes.
With the Smart Joint Access inspection opening, operators can quickly access and assess the condition of both joints without disassembly, enabling immediate verification of pump readiness prior to blast hole loading. This allows operators to confirm that emulsions are transferred accurately and consistently, protecting personnel, minimizing product degradation, and maintaining uniform dosing across multiple bore holes.
The combination of equal wall stator design, compact integration, flexible drives, and progressive cavity pump technology ensures continuous, reliable operation even in space-limited, high-pressure environments.
From Inspection to Operation
A leading explosives provider implemented BN pumps with SJA in open pit and underground operations. By replacing legacy pumps, inspection cycles were significantly shortened, allowing crews to complete pre-operation checks and return mobile units to productive work faster. Direct joint access through SJA enabled immediate verification, consistent emulsion dosing, and reduced downtime caused by joint-related deviations.
“The inspection opening gives immediate confidence that each joint is secure before proceeding to bore holes,” said a site technician. “It allows us to act quickly, keeping blasting schedules on track.”
Framework agreements ensured rapid pump supply and minimal downtime, supporting multi-site operations across continents
Concrete
Digital process control is transforming grinding
Published
3 weeks agoon
February 20, 2026By
admin
Satish Maheshwari, Chief Manufacturing Officer, Shree Cement, delves into how digital intelligence is transforming cement grinding into a predictive, stable, and energy-efficient operation.
Grinding sits at the heart of cement manufacturing, accounting for the largest share of electrical energy consumption. In this interview, Satish Maheshwari, Chief Manufacturing Officer, Shree Cement, explains how advanced grinding technologies, data-driven optimisation and process intelligence are transforming mill performance, reducing power consumption and supporting the industry’s decarbonisation goals.
How has the grinding process evolved in Indian cement plants to meet rising efficiency and sustainability expectations?
Over the past decade, Indian cement plants have seen a clear evolution in grinding technology, moving from conventional open-circuit ball mills to high-efficiency closed-circuit systems, Roller Press–Ball Mill combinations and Vertical Roller Mills (VRMs). This shift has been supported by advances in separator design, improved wear-resistant materials, and the growing use of digital process automation. As a result, grinding units today operate as highly controlled manufacturing systems where real-time data, process intelligence and efficient separation work together to deliver stable and predictable performance.
From a sustainability perspective, these developments directly reduce specific power consumption, improve equipment reliability and lower the carbon footprint per tonne of cement produced.
How critical is grinding optimisation in reducing specific power consumption across ball mills and VRMs?
Grinding is the largest consumer of electrical energy in a cement plant, which makes optimisation one of the most effective levers for improving energy efficiency. In ball mill systems, optimisation through correct media selection, charge design, diaphragm configuration, ventilation management and separator tuning can typically deliver power savings of 5 per cent to 8 per cent. In VRMs, fine-tuning airflow balance, grinding pressure, nozzle ring settings, and circulating load can unlock energy reductions in the range of 8 per cent to 12 per cent. Across both systems, sustained operation under stable conditions is critical. Consistency in mill loading and operating parameters improves quality control, reduces wear, and enables long-term energy efficiency, making stability a key operational KPI.
What challenges arise in maintaining consistent cement quality when using alternative raw materials and blended compositions?
The increased use of alternative raw materials and supplementary cementitious materials (SCM) introduces variability in chemistry, moisture, hardness, and loss on ignition. This variability makes it more challenging to maintain consistent fineness, particle size distribution, throughput and downstream performance parameters such as setting time, strength development and workability.
As clinker substitution levels rise, grinding precision becomes increasingly important. Even small improvements in consistency enable higher SCM utilisation without compromising cement performance.
Addressing these challenges requires stronger feed homogenisation, real-time quality monitoring and dynamic adjustment of grinding parameters so that output quality remains stable despite changing input characteristics.
How is digital process control changing the way grinding performance is optimised?
Digital process control is transforming grinding from an operator-dependent activity into a predictive, model-driven operation. Technologies such as online particle size and residue analysers, AI-based optimisation platforms, digital twins for VRMs and Roller Press systems, and advanced process control solutions are redefining how performance is managed.
At the same time, workforce roles are evolving. Operators are increasingly focused on interpreting data trends through digital dashboards and responding proactively rather than relying on manual interventions. Together, these tools improve mill stability, enable faster response to disturbances, maintain consistent fineness, and reduce specific energy consumption while minimising manual effort.
How do you see grinding technologies supporting the industry’s low-clinker and decarbonisation goals?
Modern grinding technologies are central to the industry’s decarbonisation efforts. They enable higher incorporation of SCMs such as fly ash, slag, and limestone, improve particle fineness and reactivity, and reduce overall power consumption. Efficient grinding makes it possible to maintain consistent cement quality at lower clinker factors. Every improvement in energy intensity and particle engineering directly contributes to lower CO2 emissions.
As India moves toward low-carbon construction, precision grinding will remain a foundational capability for delivering sustainable, high-performance cement aligned with national and global climate objectives.
How much potential does grinding optimisation hold for immediate energy
and cost savings?
The potential for near-term savings is substantial. Without major capital investment, most plants can achieve 5 per cent to 15 per cent power reduction through measures such as improving separator efficiency, optimising ventilation, refining media grading, and fine-tuning operating parameters.
With continued capacity expansion across India, advanced optimisation tools will help ensure that productivity gains are not matched by proportional increases in energy demand. Given current power costs, this translates into direct and measurable financial benefits, making grinding optimisation one of the fastest-payback operational initiatives available to cement manufacturers today.
Concrete
Refractory demands in our kiln have changed
Published
3 weeks agoon
February 20, 2026By
admin
Radha Singh, Senior Manager (P&Q), Shree Digvijay Cement, points out why performance, predictability and life-cycle value now matter more than routine replacement in cement kilns.
As Indian cement plants push for higher throughput, increased alternative fuel usage and tighter shutdown cycles, refractory performance in kilns and pyro-processing systems is under growing pressure. In this interview, Radha Singh, Senior Manager (P&Q), Shree Digvijay Cement, shares how refractory demands have evolved on the ground and how smarter digital monitoring is improving kiln stability, uptime and clinker quality.
How have refractory demands changed in your kiln and pyro-processing line over the last five years?
Over the last five years, refractory demands in our kiln and pyro line have changed. Earlier, the focus was mostly on standard grades and routine shutdown-based replacement. But now, because of higher production loads, more alternative fuels and raw materials (AFR) usage and greater temperature variation, the expectation from refractory has increased.
In our own case, the current kiln refractory has already completed around 1.5 years, which itself shows how much more we now rely on materials that can handle thermal shock, alkali attack and coating fluctuations. We have moved towards more stable, high-performance linings so that we don’t have to enter the kiln frequently for repairs.
Overall, the shift has been from just ‘installation and run’ to selecting refractories that give longer life, better coating behaviour and more predictable performance under tougher operating conditions.
What are the biggest refractory challenges in the preheater, calciner and cooler zones?
• Preheater: Coating instability, chloride/sulphur cycles and brick erosion.
• Calciner: AFR firing, thermal shock and alkali infiltration.
• Cooler: Severe abrasion, red-river formation and mechanical stress on linings.
Overall, the biggest challenge is maintaining lining stability under highly variable operating conditions.
How do you evaluate and select refractory partners for long-term performance?
In real plant conditions, we don’t select a refractory partner just by looking at price. First, we see their past performance in similar kilns and whether their material has actually survived our operating conditions. We also check how strong their technical support is during shutdowns, because installation quality matters as much as the material itself.
Another key point is how quickly they respond during breakdowns or hot spots. A good partner should be available on short notice. We also look at their failure analysis capability, whether they can explain why a lining failed and suggest improvements.
On top of this, we review the life they delivered in the last few campaigns, their supply reliability and their willingness to offer plant-specific custom solutions instead of generic grades. Only a partner who supports us throughout the life cycle, which includes selection, installation, monitoring and post-failure analysis, fits our long-term requirement.
Can you share a recent example where better refractory selection improved uptime or clinker quality?
Recently, we upgraded to a high-abrasion basic brick at the kiln outlet. Earlier we had frequent chipping and coating loss. With the new lining, thermal stability improved and the coating became much more stable. As a result, our shutdown interval increased and clinker quality remained more consistent. It had a direct impact on our uptime.
How is increased AFR use affecting refractory behaviour?
Increased AFR use is definitely putting more stress on the refractory. The biggest issue we see daily is the rise in chlorine, alkalis and volatiles, which directly attack the lining, especially in the calciner and kiln inlet. AFR firing is also not as stable as conventional fuel, so we face frequent temperature fluctuations, which cause more thermal shock and small cracks in the lining.
Another real problem is coating instability. Some days the coating builds too fast, other days it suddenly drops, and both conditions impact refractory life. We also notice more dust circulation and buildup inside the calciner whenever the AFR mix changes, which again increases erosion.
Because of these practical issues, we have started relying more on alkali-resistant, low-porosity and better thermal shock–resistant materials to handle the additional stress coming from AFR.
What role does digital monitoring or thermal profiling play in your refractory strategy?
Digital tools like kiln shell scanners, IR imaging and thermal profiling help us detect weakening areas much earlier. This reduces unplanned shutdowns, helps identify hotspots accurately and allows us to replace only the critical sections. Overall, our maintenance has shifted from reactive to predictive, improving lining life significantly.
How do you balance cost, durability and installation speed during refractory shutdowns?
We focus on three points:
• Material quality that suits our thermal profile and chemistry.
• Installation speed, in fast turnarounds, we prefer monolithic.
• Life-cycle cost—the cheapest material is not the most economical. We look at durability, future downtime and total cost of ownership.
This balance ensures reliable performance without unnecessary expenditure.
What refractory or pyro-processing innovations could transform Indian cement operations?
Some promising developments include:
• High-performance, low-porosity and nano-bonded refractories
• Precast modular linings to drastically reduce shutdown time
• AI-driven kiln thermal analytics
• Advanced coating management solutions
• More AFR-compatible refractory mixes
These innovations can significantly improve kiln stability, efficiency and maintenance planning across the industry.
UltraTech Appoints Jayant Dua As MD-Designate For 2027
Merlin Prime Spaces Acquires 13,185 Sq M Land Parcel In Pune
Adani Cement and Naredco Partner to Promote Sustainable Construction
Operational Excellence Redefined!
World Cement Association Annual Conference 2026 in Bangkok
UltraTech Appoints Jayant Dua As MD-Designate For 2027
Merlin Prime Spaces Acquires 13,185 Sq M Land Parcel In Pune
Adani Cement and Naredco Partner to Promote Sustainable Construction
Operational Excellence Redefined!


