Economy & Market

Microgrids can transform cement plant energy sourcing

Published

6 months ago

September 10, 2025

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Dr Avijit Mondal, Deputy General Manager (DGM), NTPC Energy Technology Research Alliance (NETRA), NTPC, explains in detail how power sector innovations are opening new frontiers for energy-intensive industries like cement.

As the cement sector seeks pathways to efficiency and decarbonisation, lessons from the power sector—particularly thermal and renewable energy research—are becoming indispensable. Dr Avijit Mondal, Deputy General Manager, NTPC Energy Technology Research Alliance (NETRA), NTPC, shares how innovations ranging from microgrids and biomass co-firing to CO2-to-methanol pilots and CFD modelling are reshaping cement plant energy sourcing. In this conversation, he outlines a roadmap where power plant technologies and cement operations converge to deliver cleaner, more reliable and cost-efficient production.

How does research in thermal power plants drive energy efficiency for heavy industrial loads such as cement?
Cement is India’s second-largest industrial power consumer, and every kilowatt-hour saved or sourced from cleaner energy directly lowers the cost of clinker production. Research and development in thermal power plants (TPPs) plays a critical role in achieving these gains, delivering benefits through high-efficiency generation, flexible operation, improved power quality and integrated carbon management. Most importantly proper combustion in boilers (thermal power plants) creates good quality fly ash (bottom ash), which is an important raw material for the cement industry.
Advancements such as supercritical and ultra-supercritical steam cycles, improved turbine designs and auxiliary systems with variable frequency drives on feedwater, induced-draft, and forced-draft fans lower heat rates by 1.5 per cent to 3 per cent, reducing both grid emission factors and delivered tariffs-especially during off-peak hours. Ultra-low-load stable operation enables cement plants to shift energy-intensive processes such as finish grinding and mine operations to off-peak night hours, reducing power costs. R&D in coal-quality handling-using on-belt analysers and AI-driven blending-enhances steam generator stability, reducing ramp losses and improving heat rates, which in turn minimises power price volatility for industrial users.
Power quality research, including stat-coms, synchronous condensers and harmonic filters, stabilises voltage and frequency for large drives, reducing motor losses, tripping incidents and rework in cement operations. Flexible load management and industrial demand response strategies co-developed with utilities-such as automated compressor/crusher set-backs and ‘grind-at-night, burn-by-day’ schedules-help align cement energy use with renewable-rich periods. On the thermal side, TPP waste-heat recovery concepts, air preheaters and regenerative exchangers have been adapted for cement kilns, enabling exhaust gas recovery for process heat or captive power.
Parallel work in low-NOx combustion, biomass co-firing and fuel preparation optimises kiln firing efficiency, while digitalisation and predictive analytics, pioneered in TPP operations, enhance process control, maintenance scheduling, and energy loss detection in cement plants. Cogeneration models allow direct supply of steam or heat from nearby TPPs, and joint carbon capture and utilisation research offers pathways to mineralise captured CO2 in cement or use it in curing, further reducing emissions.
The combined effect of these interventions is substantial: incremental heat-rate improvements alone can lower grid CO2 intensity by 20-40 g/kWh, while smart time-of-use alignment can cut plant power costs by 2 per cent to 4 per cent. Together, these innovations lower specific energy consumption, improve process stability, and make cement manufacturing more cost-competitive and sustainable.

What innovations in microgrids or Solar/BESS could benefit cement power sourcing microgrid architecture for cement?
Cement manufacturing is among the most energy-intensive industrial processes, with continuous high loads from kilns, grinding mills, crushers and conveyors. Integrating a hybrid behind-the-meter microgrid offers a powerful solution to improve energy efficiency, reduce power costs, and enhance operational resilience. A typical integrated cement plant can deploy a hybrid system comprising 8-15 MWp of rooftop and ground-mounted solar PV, 8-25 MW of waste heat recovery (WHR) capacity, and a Battery Energy Storage System (BESS) sized for 15-30 minutes of peak plant load. In this configuration, solar PV supplies the daytime base load for processes like grinding and material transport, WHR delivers steady baseload power for kiln and cooler exhaust, and BESS handles ramping and flicker control. The BESS also enables peak shaving during kiln starts or crusher surges, provides frequency and VAR support to safeguard large variable frequency drives (VFDs), smooths renewable fluctuations to stabilise kiln induced-draft (ID) control, and offers black-start capability for captive power systems.
The system is coordinated by an advanced Energy Management System (EMS) with process awareness. This EMS forecasts solar generation and plant load, dynamically reschedules non-critical operations such as mills, packing lines and mine conveyors into solar-rich periods, and isolates the kiln and calciner from disturbances. It can also manage load shifting strategies, such as ‘grind at day, burn at night,’ aligning with renewable-rich grid periods.
Recent innovations in industrial-scale BESS include long-duration storage (4-8 hours) to cover full or partial shifts on solar and WHR, and high-C-rate batteries capable of handling sudden restarts or process surges. Some plants also deploy DC-coupled PV + BESS configurations, which reduce inverter losses and improve round-trip efficiency compared to AC-coupled systems. Capturing curtailed renewables by storing excess solar or wind energy in BESS or using it for low priority loads such as precursing further enhances system value.

Supporting infrastructure includes microgrid-ready switchgear and fast-transfer/static breakers to enable seamless islanding from the grid without tripping large motors. The architecture supports multiple operating modes:

Grid-Connected Optimised Mode: Minimises grid draw during peak tariff hours.
Island Mode: Operates on WHR + Solar + BESS during grid outages.
Peak Shaving Mode: Uses BESS to offset short-term spikes, reducing demand charges.
Load Shifting Mode: Aligns high-energy processes with solar availability.

Impact: Field implementations show 18 per cent to 28 per cent reductions in grid imports, 3 per cent to 6 per cent lower specific power costs, improved power quality (fewer nuisance trips), and measurable gains in kiln uptime. By combining solar, WHR, storage and intelligent control, microgrids can transform cement plant energy sourcing into a cleaner, more reliable and more cost-effective system.

How does a flue-gas CO2-to-methanol pilot translate to process efficiencies?
A flue-gas CO2-to-methanol pilot can translate into process efficiencies for both power plants and the cement industry in ways that go beyond just making methanol-it can also improve energy utilisation, plant integration and operational flexibility.

Here’s the breakdown in context:

A. Productive Use of a Waste Stream

Traditional: Flue gas CO2 is a liability-needs to be vented or captured and stored, consuming energy without direct revenue.
With CO2-to-Methanol: CO2 becomes a feedstock for a value-added product (methanol), effectively monetising a waste stream.
Efficiency Link: This improves the overall resource efficiency of the plant because the carbon in the fuel/raw material is not wasted but transformed into a marketable chemical.

B. Integration with Heat and Power Flows

The hydrogen for methanol synthesis (via water electrolysis) requires significant electricity, ideally from renewable or low-cost surplus power.
In power plants: The process can use low-grade waste heat from turbines or economisers to preheat CO2/H2 streams, reducing compression and reaction energy.
In cement plants: Kiln and clinker cooler waste heat can play the same role, allowing higher overall thermal efficiency without disrupting clinker production.

C. Smoothing Power Plant Load and Improving Capacity Factor

Electrolysers for H2 production can act as a flexible load:
Ramp up when grid demand is low or renewable generation is high.
Ramp down when power demand is high.
Benefit for TPPs: Reduces the need for inefficient low-load operation and enables steadier turbine efficiency.

Benefit for cement plants: If tied to an on-site WHR + PV/BESS microgrid, it can soak up excess renewable/WHR power during low cement demand periods.

D. Synergy with Flue Gas Conditioning

The CO2 capture step for methanol production often includes flue gas cleaning (removing SOx, NOx, particulates).
This upgrades the quality of flue gas, which can reduce corrosion/fouling in downstream WHR boilers, improving plant availability and heat recovery efficiency.

E. Reduction in Carbon Intensity

Power sector: Each tonne of CO2 converted to methanol lowers net emissions, improving compliance with carbon pricing or emission norms.
Cement sector: Reduces CO2 intensity per tonne of clinker by diverting a portion of process emissions into methanol synthesis.

F. Methanol as a Circular Energy Carrier
The methanol produced can be:

Sold as a chemical feedstock or marine fuel.
Used internally in dual-fuel boilers/turbines for backup power.

This creates an energy loop-CO2 captured from flue gas ? methanol ? reconverted to energy when needed, improving energy storage and fuel flexibility.

Can biomass co-firing methods from power plants be customised for cement kilns?
Yes-adaptation is practical, with kiln-specific care:

Transferable learnings from utility co-firing

Feedstock prep: Size reduction, torrefaction/pelletising, moisture control ? stable feeding through calciner/kiln burners.
Metering and pneumatics: Proven dosing/air-assist systems maintain steady thermal input and flame shape.
Chlorine/alkali management: Power-plant protocols for fuel qualification apply directly; in cement, they also protect clinker quality and rings.
Cement-specific customisations
Burner tuning: Biomass raises volatiles and lowers flame temperature; adjust primary/secondary air, swirl, momentum to avoid over-penetration or CO spikes.
Ash chemistry: Track K2O/Na2O/Cl and P2O5 to manage coating and alite formation; limit certain agri residues unless pre-leached or blended.
Where to fire: Higher substitution is often easier in the calciner than main burner; start 10 per cent to 20 per cent TSR in calciner, step up with monitoring.
Outcomes: 15 per cent to 35 per cent thermal substitution is realistic with prepared biomass; 1 per cent to 4 per cent specific heat consumption (SHC) reduction from improved combustion stability and moisture trimming.

How does CFD modelling optimise combustion for lower fuel use and emissions?
Computational Fluid Dynamics (CFD) has emerged as an indispensable tool for optimising energy efficiency, combustion stability, and emissions control in cement manufacturing. By simulating the three-dimensional flow dynamics and combustion chemistry inside the kiln, calciner, tertiary air ducts, and burners, CFD provides a deep, visual understanding of how gases, fuels and solids interact. These insights enable targeted design improvements and operational fine-tuning, ultimately reducing energy consumption and extending equipment life.
Design and operational applications. CFD modelling allows engineers to evaluate and optimise critical parameters including:

Burner Quarles and Jet Geometry: Adjusting jet angles, swirl intensity, and momentum ratios for ideal flame characteristics.
Airflow Distribution: Balancing secondary and tertiary air splits to match process demand.
Calciner Staging: Sequencing combustion zones to maximise calcination efficiency.
SNCR/AFR Injection Points: Locating selective non-catalytic reduction systems and alternative fuel inlets for optimal mixing and burnout.

Efficiency and performance levers are identified through CFD

Burner Optimisation: Tailoring swirl and jet momentum to create a narrower, elongated flame enhances heat transfer to the kiln bed, delivering a 0.5 per cent to 2 per cent reduction in specific heat consumption (SHC).
Optimised Calciner Staging: Achieving complete calcination at reduced excess air levels cuts NO emissions by 15 per cent to 30 per cent while avoiding the energy penalties of over-firing.
Hot-Spot Mitigation: Detecting and eliminating localised high-temperature zones prevents ring formation and coating build-ups, extending refractory life and improving uptime-a significant indirect energy saving.
Strategic AFR Placement: Injecting late-volatile alternative fuels in zones with the right oxygen and temperature balance avoids CO spikes and unburnt fuel losses.

The power of CFD lies not only in simulation but also in validation and integration. Best practice involves confirming model predictions through on-site measurements, including kiln hood and calciner thermography, CO/NOx traverses, and clinker microscopy. Once validated, these insights can be locked into operations using Advanced Process Control (APC) systems, ensuring consistent, long-term efficiency gains.

What role will hydrogen technologies play in decarbonising heavy industries?
Near-term actions (0-5 Years)

Hydrogen Enrichment of Burners (5 per cent to 20 per cent): Enhance flame stability and precision, enabling higher biomass and alternative fuel (AFR) substitution without incurring CO emissions penalties.
Green Oxygen Integration: Use oxygen generated from electrolysers to reduce excess air requirements and achieve better stoichiometric control, lowering NOx formation.
Power-to-Heat Applications – Deploy electro-boilers and electric dryers for plant auxiliaries in solar-rich regions, freeing up fossil-fuel-derived heat for the kiln.
Medium-term actions (5-10 Years)
Hydrogen-Ready Burners: Install kiln and calciner burners designed for high hydrogen blends, with ammonia used as a hydrogen carrier and cracked near the point of use.
E-Fuels Co-Firing: Incorporate e-methanol or e-syngas to provide dispatchable, low-carbon thermal energy.

How are ash or waste-heat recovery (WHR) technologies from power plants applicable to cement production?
Ash utilisation

Fly Ash in Blended Cements (PPC/PSC): Substituting 25 per cent to 35 per cent clinker with fly ash significantly reduces thermal load and CO2 intensity. Performance depends on Loss on Ignition (LOI), fineness, and phase composition; selectively harvested dry-silo ash offers the most consistent quality.
Bottom Ash / Pond Ash: Usable in certain
products after classification and grinding, though attention is needed to control unburnt carbon and contaminants.
FGD Gypsum: Flue Gas Desulphurisation gypsum from power plants provides a dependable alternative to natural gypsum for setting regulation.

Waste heat and power integration
• Cement WHR Systems: Using AQC/SP boilers with steam turbines or Organic Rankine Cycle (ORC) units typically recovers 20-35 kWh/t clinker. Best practice involves applying utility pinch-analysis learnings, controlling fouling,
and optimising condenser pressure for uptime and efficiency.
• Cross-Industry Synergies: Co-location with power plants enables use of their low-grade heat (or CO2 capture waste heat) for pre-drying alternative fuels or raw mix; conversely, WHR output from cement plants can supply auxiliary loads during grid peak demand.
• Circular Economy Benefits: Combining ash and FGD gypsum utilisation closes the mineral loop, while WHR and low-grade heat recovery close the energy loop-together lowering Specific Heat Consumption (SHC) and Scope 1 and 2 emissions.
A practical 6-step roadmap for cement plants
• Step 1: Energy Mapping and Pinch Analysis: Assess kiln, calciner, mills, and auxiliaries to identify 1 per cent to 3 per cent SHC savings.
• Step 2: CFD and Advanced Process
Control: Optimise burner, calciner, and AFR injection points for improved efficiency and emissions control.
• Step 3: Solar-WHR-BESS Microgrid: Implement process-aware Energy Management Systems to achieve 15 per cent to 20 per cent peak-shaving.
• Step 4: Biomass/AFR Scale-Up: Apply fuel-lab testing protocols to safely reach 20 per cent to 30 per cent Thermal Substitution Rate (TSR) in the calciner first.
• Step 5: CO2-to-X Pilots: Integrate heat
cascade systems and O2 reuse where green power is accessible.
• Step 6: Power-Sector Partnerships: Secure agreements for deep-turndown tariffs, power-quality guarantees, and consistent Class-A fly ash and FGD gypsum supply.

With contribution from Dr Gaurav Richhariya,
Executive R&D (Ash Technology), NTPC Energy Technology and Research Alliance (NETRA), NTPC.

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Economy & Market

Smart Pumping for Rock Blasting

Published

1 week ago

March 2, 2026

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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 ago

February 20, 2026

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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 ago

February 20, 2026

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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.