Cement companies should treat a blend of OPC and virgin fly ash as a benchmark, in terms of workability, cost, strength, etc, when setting performance targets for the production of PPC. The usage of PPC or a blend of OPC and fly ash has become the pressing need of today to maintain sustainability in construction, writes Avijit Chaubey, R&D Head of ACC.
Much research has been carried out on properties of concrete containing fly ash as replacement for cement. It is a well-known fact that fly ash holds many positive advantages in terms of resistance to sulphate attack, alkali silica reaction, carbonation, chloride attack and economic benefits to users, or in terms of conservation of resources (since it replaces a part of Ordinary Portland Cement). In addition to these advantages, fly ash also reduces the heat of hydration on account of its comparatively slow reactivity at early ages. These advantages/ facts are very well known across the construction community. The main reason fly ash is able to perform this way is because of its pozzolanic property by virtue of which it reacts with by product of C3S/ C2S hydration i.e, CaOH2(CH). CH being an unstable material both chemically and physically creates a problem in the concrete, leading to problems in durability. The chemical instability of CH relates to its tendency to react with:
1) Sulphates to form CaSO4 which further reacts with C3A (after concrete has hardened) to form expansive ettringite. This is a sulphate attack.
2) It produces a highly alkaline environment due to which Si-O-Si (silicate bond present in aggregates which leads to alkali silica reaction) reacts with water to form expansive silanol or silica gel.
3) CH is a crystalline material which possesses some strength but it has a tendency to react with atmospheric CO2 to form CaCO3, which by nature is an amorphous material possessing no strength.
4) On account of its physical instability, it is highly soluble in water, and leaches out of concrete, forming pores. These pores get interconnected to form a permeable concrete. Chlorides, carbon dioxide find their way into the concrete through these pores, thereby accelerating the process of corrosion in the reinforcement. (Prakash Mehta, 2008.) It is clear that most of the problems relating to durability involve CH. The solution to this problem has been found through replacement of some percentage of Ordinary Portland Cement with a suitable pozzolanic material.
A pozzolanic material is characterised by its property of reactivity with CH in presence of moisture to form tricalcium silicate hydrate gel, (the binding material in hardened concrete). Fly ash produced from thermal power plants, has proven to be a good pozzolanic material, and is widely used to replace a certain percentage of OPC in concrete. Indian standards, which guide the usage of fly ash in concrete, have identified different ways to use fly ash in concrete. IS: 3812 lays down requirement for different uses of fly ash in concrete; they are, for use as admixture, as pozzolana and as fine aggregate in concrete. It is interesting to note that fly ash can be used in production of OPC in percentages not more than 5 per cent (admixture) to improve the performance of OPC (IS 8112:1989, IS 12269:1987).
Prejudices
Although most of the advantages relating to fly ash are well known among engineers, at least theoretically, it is unfortunate to note that most do not encourage fly ash as replacement of OPC in concrete. Some government projects, too, do not have the provision for replacement of OPC with fly ash.
The main reason is inadequate understanding of the effect of fly ash on concrete strength. Whenever fly ash is used as a replacement for OPC, the practice is to equate it with OPC in terms of strength gain. From actual experience, it is found that OPC with fly ash leads to slow strength gain compared to OPC. Moreover, concrete with fly ash is more sensitive towards temperature as compared to OPC. Meaning, a decrease in temperature reduces the strength gain rate in fly ash concrete more than in concretes with pure OPC. Probably, this has led to so- called failures of fly ash concretes in certain laboratories. The fear is not predominant only in construction industry but even cement companies which advocate usage of PPC over OPC and prefer OPC cement for production of concrete in their RMC plants.
Of course, using virgin fly ash for blending in concrete at the batching plant is much better than using inter-ground fly ash and OPC in the form of PPC. The sole reason being that fly ash particles are spherical in shape, due to which they impart better workability to the concrete in which they are introduced, whereas when interground with clinker to form PPC, the shapes get distorted, and these particles no more have their shape in a spherical form. The result is higher water demand for desired workability. It won-Æt be wrong to say that water demand is a cumulative effect of particle shape, particle size distribution and fineness, implying that even after grinding of fly ash and OPC, there could be the possibility that PPC cement may have lower water demand up to a certain time of grinding, as compared to OPC and un-ground fly ash. However, the usual observation on site unfolds a different story, with water demand actually being higher for PPC than OPC in combination with virgin fly ash. This obviously calls for refining the process for production of PPC, with optimising the time of grinding so that there is minimum water demand. HCC has come across cases when a standard consistency of 26 per cent with a blend of OPC and fly ash was achieved, i.e, a reduction by two percent when tested for pure OPC which gave a standard consistency of 28 per cent.
What needs to be done?
Figure 1 gives a clear picture of the effect on strength by replacing cement with fly ash. It can be seen that strength developed in concrete with fly ash is always less than in OPC concrete, whereas most of cement companies show higher strength of fly ash-based concrete beyond 28 days in comparison to concrete with a equal quantity of OPC. Fly ash needs to be characterised by its Cementing Efficiency Index (Peter Hewlett, 2004) for different temperatures at different ages in combination to particular cement.
W = W . – – – – – – – – – – – – (i) Cs (C+FK) Here W, C & F are the weights of water, Ordinary Portland Cement and fly ash respectively for the given mix, and K is the cementing efficiency index of the fly ash. W/Cs is the equivalent water cement ratio, i.e, the required water cement ratio for the same strength but without fly ash. If we try to find out the cementing efficiency indices of the fly ash used in a trial, reproduced in Table 1 (Amit Mittal, 2008), it turns out to be something between 0.45 to match strength for 28 days and 0.8 to match strength at 90 days (for 40per cent replacement with Fly ash) and 0.63 to match strength for 90 days (for 50per cent replacement with fly ash) (figure 2). The steps to calculate cementing efficiency index is shown below: from Table 1 we can find that for OPC (without fly ash), with 350 kg cement and 0.45 W/C ratio the 28 day strength is 37.8 MPa. The closest strength at 28 days is achieved with 450, 40per cent mix (total cementitious, percentage fly ash) using W/C ratio of 0.35.
Using Eqn. (i):
W = W
Cs (C+FK)
Thus, 0.45= 158
(270+180*K)
Thus, K= 0.45 (This index is to match strength for 28 days of OPC concrete).
This data can then be used to design concretes with the desired percentage of fly ash for the required age of concrete.
Another interesting property of fly ash should be incorporated in the mix design procedure, i.e, its ability to produce a better workability with lower water contents. A higher percentage of fly ash in cementitious material can yield better workability. M.L. Gambhir proposes multiplication factors both for water content and cementitious content for different percentages of fly ash (M. L. Gambhir, 2004).concrete made with OPC and fly ash when compared to concrete made with equal quantity of OPC alone, shows better durability in terms of Rapid Chloride Penetration tests, sulphate resistance (Peter Hewlett, 2004), ASR, etc, whereas in the limits for cement content in IS:456- 2000, minimum cement content holds the same for all cements. It rather would be more appropriate to specify limits for test results on concrete/ mortar for various aspects of durability viz. RCPT, sulphate resistance, mortar bar expansion (ASR), etc, rather than specifying minimum cement content per cubic metre of concrete.
If PPC cement, available in the market, were to be compared with blend of same brand OPC and same fly ash, the cost for production of same grade of concrete would be much less in case of concrete made with blend of OPC and fly ash. The reason for comparing costs is to point out the inefficient usage of resources by cement companies. If we had to see this problem from the point of sustainability, it would be clear that energy consumption in producing equivalent grade of PPC concrete will be much higher than the energy for OPC and PFA blend concrete. Another reason for stating the superiority of OPC and PFA blend is the situational advantage to increase or decrease the fly ash content to accelerate the production rate in construction. For example, construction projects in sub- zero temperatures demand faster strength gain rate of concrete to avoid damages due to freezing. In the case of pre-stressed concrete, pre-stressing is done only after achievement of a certain strength; the faster the strength achievement, the more efficiently resources can be handled. In these conditions, if one had to use PPC, the cost can work out to be much higher than OPC, since in these cases early age strengths holds more priority than 28 day strength.
Example
An OPC concrete gives 30 MPa strength at 28 days for W/Cs ratio of 0.5. The water content is 160 litres and cement content 320 kg per cubic metre of concrete. Now we desire to use 40 per cent fly ash for replacing OPC, which has a cementing efficiency Index of 0.4 for 28 days, with the available OPC, so that the strength achieved is equivalent to OPC concrete at 28 days.
Solution
Fly ash reduces water demand say by 12 per cent as compared to OPC (M. L. Gambhir, 2004), so we reduce the water content to 141 litres.
W = W
Cs (C+FK)
i.e. 0.5 = 141 . (Since Fly ash is 40 per cent of total cementitious)
(0.6Cm + 0.4Cm*0.4)
So, Cm= 372 Kg per cubic metre (total cementitious content).
Now the cementitious content is 372 kgs per cubic metre of concrete out of which 150 kgs shall be fly ash and 222 kgs shall be OPC. The water cement ratio required now will be 0.38.
If the strength required was at 90 days instead of 28 days, and the cementing efficiency index found was 0.8, the total cementitious content then would have been 307 Kg per cubic metre of concrete and water cement ratio required would be 0.46 (based on similar calculations shown above).
Economics
320 kg of OPC costs much higher than combination of 222 kgs of OPC and 150 kgs of fly ash. The difference could be somewhere near Rs. 250 per cubic metre of concrete (OPC cost- Rs. 5/kg and fly ash cost- Rs. 1.6/kg). The heat of hydration from 320 kg of OPC at 3 days has been found out to be somewhere near 17.7 Mcal(Mega Calories), whereas with the alternative combination, the heat of hydration comes down to 14.9 Mcal per cubic metre of concrete (based on actual test results as shown in table 2 and interpolation from SP 23: 1982 considering linear relationship between heat of hydration and fly ash content), i.e, a decrease by 15 per cent of heat in three days.
Each tonne of cement produced releases 0.95 tonnes of CO2 in atmosphere (including energy consumption, if the heat is coal generated). It has been possible to reduce OPC by one hundred kgs per cubic metre, or by 30 per cent. Thus by replacing 40 per cent cement, we are able to reduce CO2 emissions by 44 million tonnes per annum, considering 155 million tonnes cement production per annum in India Moreover, the fly ash which otherwise creates an environmental nuisance will be used up in something productive.
Conclusion
It becomes vital to look into this matter, and make necessary changes in the mix design procedures for concrete. It also is very necessary to include cementing efficiency index and capacity to improve workability when used for replacement of OPC. Keeping in view that durability of concrete increases when fly ash is used to replace OPC, the same limits of cementitious content for durability does not seem justified for different types of cement. Rather, limits on test results of durability for various tests of concrete should be specified. Production of PPC is done by inter- grinding clinker of OPC and fly ash, which consumes up energy/ resources. If comparisons of cost of concrete made with PPC and concrete made with blend of OPC and fly ash were to be done, the latter would mostly outperform the concrete made with PPC.
Cement companies should treat blend of OPC and virgin fly ash as benchmark, in terms of workability, cost, strength etc, when setting the performance targets for production of PPC. Although usage of PPC or blend of OPC and fly ash has become need of today to maintain sustainability in construction, it won’t be beneficial to completely stop production of OPC, as it proves economical in comparison to fly ash based concrete when high early age strengths are required from concrete.
Adam Smith in his `invisible hand` theory proposes that allocation of finite resources is done by an invisible hand. This invisible hand is referred to as price in terms of economics, if it were to be defined in a single word. The scarcer the resources are, the higher the cost of the product made from these resources. So, if we have to choose an indicator for sustainable construction, the best indicator would be the cost. Thus, two different concretes made with different costs but the same strength can easily indicate which is better in terms of sustainability. Standards can look into the problem of sustainability by also including cost of production of cement (since cost reflects the efficiency of usage of resources) per MPa strength of cement.
Although this might be a crude step at this moment since not much data is available, it will surely lead to better usage of resources in future. To start with, there could be data generated on effects of grinding of cementitious material on workability, strength, etc. Then a suitable method can be devised to find optimum solution from the available data.
Two cement concrete pavement roads covering a total stretch of 2.2 km in Akhoya village were inaugurated on 27th June 2026 by MLA Nuklutoshi Longkumer, who attended as the special guest. The project comprises the one km L Pangersowa Road and the one point two km Longchara Junction to RC Chiten Jamir Memorial Government High School road. A formal programme followed the inauguration at the school auditorium.
A technical report was presented by Er Waloniba of the Urban Engineering Wing-III, Kohima, which stated the project was sanctioned in March 2026 under the Special Assistance to States for Capital Investment scheme for 2025-26 at a sanctioned cost of Rs 29.1 million (mn). The work order was issued to M/s Ensign Construction on thirtieth April 2026 with a stipulated completion period of 12 months. Work commenced on fourth May 2026 and was completed on sixth June 2026, with the contractor and team finishing the tasks in around two months. The project included a single-lane cement concrete pavement with side drains, two slab culverts and breast walls at required locations.
Longkumer acknowledged the Chief Minister, the advisor for urban development, contractors and other stakeholders for the allocation and support, and he commended the contractor for early completion. He noted that cooperation from landowners and the community had been important in resolving land related issues that can otherwise delay developmental works. He emphasised that planned developmental activities carried out with collective effort would enable more projects to be implemented successfully.
The headmaster of RC Chiten Jamir Memorial Government High School, I Chubasenba Longkumer, outlined the school background, noting it was established in 1962, was earlier known as Government High School Changtongya and was renamed in 2014. Local representatives said the improved approach roads would ease access for students, staff, patients and the general public and fulfil a long standing aspiration of residents. A dedicatory prayer was offered by the pastor and the programme concluded with a ribbon cutting attended by village council and town council representatives.
Indian Cement Review (ICR) and Fuller Technologies brought industry, policy and technology leaders together to discuss how cement innovation can drive green construction at scale, writes Rakesh Rao.
India is building at a pace few countries can match. Highways, airports, housing, logistics parks, industrial corridors and urban infrastructure are reshaping the country’s economic geography. But beneath this growth story lies a difficult question: can India continue to build at scale without locking itself into a high-carbon future?
That question formed the core of an online panel discussion titled “Driving Green Construction Through Cement Innovation”, organised by Indian Cement Review (ICR) in association with Fuller Technologies as the Presenting Partner on June 25, 2026. The webinar brought together experts from cement technology, R&D, global industry platforms, building performance policy and international development cooperation to examine how low-carbon cement and material innovation can accelerate India’s green construction transition.
The discussion came at a crucial time. India has committed to achieving net-zero emissions by 2070 and reducing the carbon intensity of its economy by 45 per cent by 2030. At the same time, the country’s construction sector is expanding rapidly, driven by urbanisation, infrastructure development, housing demand and industrial growth. Cement, as one of the most widely used construction materials, sits at the heart of this transition. It is indispensable to development, but also central to the challenge of reducing embodied carbon in buildings and infrastructure.
Moderated by Nitika Krishan, Senior Urban Infrastructure and Sustainable Policy Consultant, the panel featured:
Dr Hemantkumar Aiyer, VP and Head R&D, Nuvoco Vistas Corp Ltd;
Devika Wattal, Innovation Lead, Global Cement and Concrete Association (GCCA);
Dr Sunita Purushottam, MD, GBPN India (Global Buildings Performance Network); and
Vaibhav Rathi, Senior Technical Advisor, GIZ (the German Agency for International Cooperation)
Setting the tone for the discussion, Nitika Krishan underlined the scale of the challenge before the sector. “The question before us is no longer whether we build, but how we build sustainably,” she said. She pointed out that construction accounts for nearly 40 per cent of global energy-related carbon emissions when both operational and embodied carbon are considered. Cement production, she added, remains one of the hardest industrial processes to decarbonise.
For India, this is not merely an environmental issue. It is a development issue, a competitiveness issue and increasingly, a market issue. As one of the world’s largest cement producers and among the fastest-growing construction markets, India’s material choices will influence the carbon trajectory of its built environment for decades. As Krishan observed, sustainability solutions in economies such as India must not remain limited to laboratory success. They must be scalable, commercially viable and practical at national level.
The innovation gap: From technology to market
Experts believe that there is a need to bridge the innovation gaps for making decarbonisation in cement and concrete scalable. Devika Wattal of GCCA, explained, “The starting point must be the core cement manufacturing process itself. The first and foremost is the heart of our process, the heart of cement manufacturing. How do we reduce clinker? That is always a topic where industry is working very intrinsically.”
Clinker reduction remains one of the most important pathways for lowering emissions in cement. Since clinker production is energy-intensive and chemically emits carbon dioxide, reducing the clinker factor through supplementary cementitious materials (SCMs), blended cements and new chemistries can have a significant impact. Wattal also noted that carbon capture, utilisation and storage (CCUS) will have a role, though it may not be the first lever for all markets.
However, she stressed that innovation cannot stop at technology development. A solution that works in the lab must also be adaptable to industry, scalable in production and acceptable in construction practice. “It is important for that innovation to be adaptable, to be scalable, and so that it can be executed in real time,” she said.
Wattal also called for stronger enabling systems around innovation. These include performance-based standards, product-level embodied carbon databases and clearer frameworks for evaluating green materials. Without these, low-carbon cement products may struggle to compete with conventional materials in procurement and design.
R&D must balance carbon, cost and performance
Bringing in the R&D perspective into the discussion, Dr Hemantkumar Aiyer of Nuvoco Vistas emphasised that low-carbon cement development cannot be treated as a single-variable exercise. Cement must perform in real construction conditions. It must deliver strength, durability, consistency and cost competitiveness, while also reducing carbon.
“The root of understanding and balancing all these aspects lies in materials, and knowing the materials,” he said.
According to Dr Aiyer, R&D teams must understand the variability of raw materials such as fly ash, slag and clinker. Different sources produce different material behaviours. This makes mix optimisation, material characterisation and processing-property relationships critical. When performance is affected, cement manufacturers must understand how strength enhancers, admixtures and other performance chemicals interact with the material system.
He also linked material science with process efficiency. Clinkerisation takes place at extremely high temperatures, around 1,400 to 1,450 degrees Celsius. Any improvement in raw mix design, process control or energy optimisation can, therefore, help reduce emissions and cost. Dr Aiyer pointed to artificial intelligence-based optimisation, Cement 4.0 tools and advanced software as important enablers for real-time process and material control.
“The more you understand the materials, the more you can control it,” he said.
LC3: The promise is proven, the sequencing is not
Limestone calcined clay cement, commonly referred to as LC3, has attracted global attention because it can reduce clinker content significantly by using calcined clay and limestone while maintaining performance in many applications. Kiranmai Sanagavarapu of Fuller Technologies said the technology itself has already moved beyond proof of concept. Fuller Technologies has worked with calcined clay technology for nearly two decades and has seen plants running in France and Ghana. These plants, she said, are meeting local and national specifications, while the economics are beginning to make sense.
“The calciner is performing, the economics is stacking up, it is making business sense to produce,” she said.
But if the technology is viable, why has adoption not scaled faster? For Sanagavarapu, the answer lies in project sequencing. Too often, clay characterisation happens after equipment is specified. This, she warned, is a backward approach because calciner design depends on clay mineralogy, kaolinite content, iron levels, reactivity, moisture and other variables.
“If you don’t know what your deposit looks like before you commit for the equipment, you are, in a way, going blind into designing,” she said.
She also identified permitting and plant integration as major bottlenecks. Environmental clearances, mining permissions and local regulatory approvals must begin early. Similarly, calcined clay must be integrated into existing grinding, blending and logistics systems from the design stage, not treated as an afterthought during commissioning.
India already has IS 18189:2023 standard for LC3, but Sanagavarapu pointed out that the standard is not yet visible enough in procurement documents. “The gap between what is technically being permitted and what the procurement is asking is the single biggest bottleneck,” she said.
In her view, successful scale-up depends on getting the sequence right: clay characterisation first, permitting in parallel, standards aligned with construction, and integration built into plant design.
India’s LC3 journey: Progress, but demand remains thin
Providing details of India’s LC3 commercialisation experience, Vaibhav Rathi of GIZ noted that JK Cement carried out the first commercial production of LC3 at its Rajasthan plant, followed by JK Lakshmi Cement three months later. These initiatives were supported by the International Climate Initiative of the Government of Germany, with IIT Delhi contributing deep institutional knowledge on LC3 research and BIS certification.
Rathi said India’s early experience has produced clear lessons. One of the biggest was the need to build capacity among regulators. While BIS certification existed, State Pollution Control Boards were unfamiliar with the technology and unsure about the approval pathway.
“The capacity building is not just needed amongst the producer and the users of the cement, but also the regulators who are working with this technology for the first time,” he said.
He also highlighted the need for better information on China clay deposits. Since China clay is currently classified as a minor mineral, centralised data on availability, quality and location is limited. If cement manufacturers are to adopt LC3 at scale, stronger mineral intelligence will be important.
The third issue is demand. LC3 has already been used in projects such as Palava City in Mumbai and Noida International Airport, but these remain limited examples. “It is in a chicken and egg situation,” Rathi said. “Cement companies are saying we need more demand, and users are saying there is not enough cement available.”
Public procurement, he suggested, could help break this cycle. If agencies such as CPWD and other public bodies begin testing, accepting and specifying LC3, it could create the market confidence needed for cement companies to invest in production and storage.
Building codes must catch up with innovation
Dr Sunita Purushottam of GBPN India argued that material choices will determine built environment emissions over the long term, but India’s current policy signals remain fragmented. Although LC3 has received BIS recognition, she pointed out that building codes, municipal bylaws, schedules of rates and sustainability codes do not yet provide uniform guidance on low-carbon cement.
“The current cement regulations are largely prescriptive and favouring traditional materials,” she said. This limits the ability of alternative materials to compete on performance, durability and emissions.
Dr Purushottam also raised the issue of taxation. Cement, including LC3, currently falls under the same GST bracket as conventional cement. A differentiated tax structure, she argued, could help accelerate market adoption. “In order for the market to demand LC3, that differentiation in the GST could go a long way,” she said.
She noted that green building certifications such as IGBC and GRIHA are already creating demand for low-carbon materials by assigning points for embodied carbon and sustainable material use. However, she said large-scale adoption will require regulatory mandates, particularly through building codes and state-level notifications.
She also cautioned that low-carbon cement alone does not solve the entire building performance problem. A material may reduce embodied carbon, but the operational carbon of a building depends on thermal performance, design, insulation and energy use. “The energy part has two elements,” she said. “One is the embodied carbon of the material itself, and the other is the operational carbon.”
Collaboration is the bridge between invention and impact
Wattal said GCCA sees innovation as a strategic priority and works through platforms that connect industry with academia and start-ups. “There is no way we will decarbonise our sector without innovation,” she said.
However, she stressed that research must be connected to actual industry challenges. Innovations developed in isolation may fail when they encounter real-world barriers such as raw material variability, plant integration, cost, standards and finance. Start-ups, too, need industry mentorship and scale-up pathways.
Wattal also flagged the importance of finance. Even strong technologies may struggle to attract investment if there is no common understanding of bankability. “We have always put projects into, is this a bankable project? But the definition of a bankable project has never been defined,” she said.
For India, she saw strong potential in its academic and start-up ecosystem, but said the challenge lies in alignment and prioritisation. The country has the research base, industrial capacity and market size. What it now needs is a coordinated route from innovation to deployment.
There is a practical concern for cement manufacturers: how can existing plants be adapted for lower emissions without compromising reliability or commercial viability?
Kiranmai Sanagavarapu addressed, “The reliability risk in calcined clay retrofit is definitely real, but it is almost always self-inflicted. The risk arises when a new process is added to an existing circuit without properly redesigning grinding and blending configurations.”
Existing cement plants, she explained, can take two broad routes. The first is external sourcing of calcined clay combined with mill optimisation. This requires lower capital investment and can potentially move in 12 to 18 months if other conditions are in place. It may reduce emissions by around 20 to 30 per cent. The second route is integrated calcination on site, which requires higher capital expenditure and longer lead times, but provides greater control over quality, supply and emissions reduction potential.
For Sanagavarapu, the principle is simple: low-carbon retrofits must be designed with intent. “Design it with an intent properly from the start. Start in the market conditions where the economics are already working,” she said.
Circularity: The overlooked advantage
According to Vaibhav Rathi, fly ash and slag are already well established in cement and construction (C&D), but construction and demolition waste remains underutilised. “C&D waste is a growing business opportunity which not many have taken up,” he said. India’s continuous construction and demolition activity creates huge volumes of waste, much of which contributes to air pollution, land degradation and material inefficiency. With the right processing and standards, this waste can be converted into useful construction products.
Rathi also pointed out that LC3 has a circular economy dimension that is often overlooked. It can use low-grade kaolin-rich clay left behind after high-grade clay is extracted for other applications. “LC3 is not only a low-carbon solution, but also a circular economy solution,” he said.
At the same time, he cautioned that LC3 in India is not yet cheap because it has not reached scale. Site-specific techno-commercial feasibility studies, supported jointly by development agencies and industry, could help companies assess whether LC3 production makes technical and financial sense at a given location.
Dr Purushottam added that India must address both low-carbon cement and construction waste together. “Both low-carbon cement and C&D waste go hand in hand. India does not have an option but to work on both,” she said.
Dr Aiyer called for policy shifts from both government and industry, including preferential purchasing of sustainable materials, minimum supplementary cementitious material requirements in public and public-private projects, and faster regulatory implementation. “If we can fast-track the regulatory standards and their implementation on the ground, that is the way to go,” he said.
From green ambition to green construction
Cement innovation is no longer only about chemistry. It is about systems. Low-carbon cement will scale only when technology, standards, procurement, finance, regulation, education and construction practice move together.
LC3 and other low-carbon technologies have shown promise. India has early commercial examples, strong research capability and growing market interest. But mainstream adoption will depend on whether demand can be created, regulators can be capacitated, standards can be embedded in procurement, and manufacturers can see a clear business case.
For a country building at India’s scale, the opportunity is enormous. Cement will continue to be central to infrastructure and urban development. The challenge now is to ensure that the cement used in India’s growth story carries a lower carbon burden.
Rakesh Rao
Participate in Cement Expo 2026 and discover how next-gen infrastructure can be built with innovations in cement.
JK Cement gained after being declared preferred bidder for the Gilund Limestone Block in Chittorgarh, Rajasthan, a lease area of 370.96 hectares. The firm saw its shares trade at Rs. 5550.05, up by 28.45 points or 0.52 per cent from the previous close of Rs. 5521.60 on the BSE. The scrip opened at Rs. 5569.15 and touched a high of Rs. 5625.00 and a low of Rs. 5531.00.
The stock recorded turnover of 1742 shares on the counter and the BSE group A stock with face value Rs. 10 has a 52 week high of Rs. 7565.00 on 20-Aug-2025 and a 52 week low of Rs. 4670.05 on 12-Jun-2026. Last one week high and low stood at Rs. 5625.00 and Rs. 5329.00 respectively. The promoters holding in the company stood at 45.66 per cent, while institutions and non-institutions held 40.61 per cent and 13.73 per cent respectively.
The e-auction conducted by the Government of Rajasthan resulted in the company being declared preferred bidder for the mining lease, and the allocation will enable the company to plan phased development of the deposit, subject to regulatory approvals. The Gilund block spans 370.96 hectares and its allocation is intended to support raw material security for the company’s cement operations in the region. The designation follows the government auction process and will allow the company to plan development and integration of the deposit into its supply chain.
The current market capitalisation stands at Rs. 430.38 billion (bn), reflecting market response to the mining news and prevailing valuation levels for the sector. Investors and analysts will watch for formal allotment and related disclosures that can clarify timelines, capital expenditure and expected production profiles. The report is intended for informational purposes and does not constitute investment advice, and market participants are advised to consult advisers before making decisions.
