Concrete

Economic Implications of Using SCMs

Published

3 years ago

November 20, 2023

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ICR analyses how the integration of supplementary cementitious materials (SCM) and the strategies thereof has catalysed the cement industry’s economic landscape, fostering streamlined processes and enhanced resource utilisation, ultimately shaping a more resilient and profitable sector within India’s economy.

The way to look at any cementitious material in modern times would be to look at the carbon intensity inherent in it in terms of CO2 emissions, such as clinker, which forms the basis for making cement. After grinding the clinker (95 per cent) with gypsum and some correctives (together at 5 per cent), its emission intensity is 849-868 kg per tonne of output. Thus, when you produce ordinary Portland cement (OPC), which contains only clinker as the base cementitious material, the emission intensity is the highest at 750-860 kg of cement output. The lower end of the band is reserved for those who use the best technology that improves thermal efficiency and electrical efficiency.
Now, OPC could be the best suited for giving the early strength of cement measured by the compressive strength in MPa. Whether you take a 3-day or 7-day or 28-day strength, OPC would remain at the highest when you compare with any other form of cement that supplements clinker in the OPC with other cementitious materials like fly ash, slag, silica fume, natural pozzolans – such as calcined clays, shale and metakaolin, sugarcane bagass ash (SCBA) or rice husk ash (RHA).
The purpose of using supplementary cementitious material is two-fold:

Economic
Environmental
The way to deal with this subject would be to look at the life cycle assessment of each of these and compute the impact. To make matters simple one may first look at the carbon intensity in each in terms of emissions and attach an appropriate environmental cost to it. Let us look at some of these numbers:
Portland Pozzolana Cement (PPC) uses a mix of 60-65 per cent clinker, 5 per cent gypsum and 25-30 per cent fly ash thus taking the overall emission to an average 700 kg per tonne of cement. Efforts have been always to look at ways of maximising fly ash and PPC specifications allow for even 35 per cent fly ash to meet the compressive strength guidelines. However, we must note that compressive strength will be lower for 3 days, 7 days and 28 days for PPC when compared with OPC by at least 8-10 per cent. If one considers the cost of fly ash that is replacing clinker, the economic impact is huge as the cost of the former is a fraction of the latter.

Economic Implications
To compute the economic benefits of fly ash in PPC there are two important factors to be considered. The grinding units that are the final delivery points of cement units must be logistically located such that the cost of fly ash could be minimised. But this is a network optimisation question and the optimisation would entail outbound logistics cost of cement as well. Most advanced economies, India included, have looked at fly ash as an economic agent that not only turns waste into wealth but also reduces environmental impact of cement emissions (850 kg to 700 kg per tonne). The reduction in the landed cost of fly ash would further improve the economics through better logistics cost optimisation and mode-mix improvements. In recent times freight charges on rail in India for fly ash have been reduced to move fly ash over longer distances.
The environmental impact over long distance haulage of fly ash thus could be brought down
using rail as the mode, a crucial factor for the life cycle assessment.
The wider economic implication could be seen in the alternative deployment of a waste that was put to landfill is now an economic alternative to clinker. Some fly ash producers like NTPC or TATA Power or Adani Power, who together produce more than 100 million tonnes of fly ash per year, could be powerful actors to sway economic balance. Fly ash brick manufacturers who operate in the smaller concentrated networks, mostly SMEs, could be the next contenders in the value balance.
Slag based cement, uses 50 per cent clinker and 45 per cent slag and 5 per cent gypsum on an average. It is the next best example of SCM making a huge difference to the economic as well as environmental impact. By replacing a large amount of clinker, slag-based cement thus makes the emission intensity of cement come down to less than 500 kg per tonne of cement. This when looked at the back of the cost of slag vis-à-vis clinker, which it replaces in the cement, the economic implication is huge. The total production of blast furnace slag is growing, despite its environmental impact and it makes an economic case for GGBS.
However, blast furnace slag or the copper smelter slag, as inputs mixed together, is not free and must compete as commodities with clinker. But game theoretic approaches to price negotiations have fructified into either contracts that are short or medium term tenured (a sharp departure from the past) or pure spot contracts through auctions, that could be well mired in quasi-collusion dynamics of all kinds (in the past). Slag producers seeing an economic opportunity (as opposed to the environmental impact they face otherwise) have mostly experimented with a mix of spot and contracting strategy. The slag benefit in cement over clinker could be in the range of 30-40 per cent looking at the range of cost dynamics that would also include transportation cost by rail.
When one adds the CO2 emission impact benefit, fly ash and slag make a stunning case.

Exploring Other Options
The next most talked about SCMs are silica fumes and natural pozzolans, but their use has been limited in most parts of the world due to economic evaluations, including logistics cost. However, this economics could be lopsided in Europe where fly ash is hardly available and slag could be following suit. Natural pozzolans like calcined clay and metakaolin are therefore in news today, especially in Europe. In India, for example, they could be traded at cement cost, whereas in Europe they could well be lower than the clinker cost.
Utilisation of fly ash in cement has been improving in India but it is still far from the developed world numbers. The old wet fly ash lying in ponds and the dry lying in ash mounds could together be in excess of 100 million tonnes. While the vertical roller mills (VRM) technologies offer great benefits overall ball mills in grinding for absorption of wet fly ash, some innovative methods to use wet fly ash without adding to cost have been developed by some. Similarly, those having a logistics advantage towards a mix of fly ash and slag have settled for composite cement that could use a blend of fly ash and slag in their grinding mix. These could offer negotiating leverage while settling contracts in fly ash and slag.
At the end, to weigh the environmental impact in concrete, which uses a mix of sand, gravel, cement and water, one must see the equation differently: in a one cubic metre of concrete, using 14 per cent cement in the mix, the CO2 emission would be of the order of 410 kg/cubic metre compared to 290 kg per cubic using 30 per cent fly ash in PPC.

–Procyon Mukherjee

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JK Lakshmi Cement to Expand EV Fleet to 120 Vehicles by March 2027

JK Lakshmi Cement has deployed more than 70 EVs across its logistics network.

Published

4 hours ago

October 30, 2026

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JK Lakshmi Cement has deployed more than 70 electric vehicles (EVs) across its logistics network and plans to increase the fleet to 120 vehicles by March 2027. The expansion is part of its decarbonisation strategy, which aims to reduce transport-related emissions and improve operational efficiency.

The company has achieved nearly 100 per cent EV-based clinker dispatches from its Sirohi plant in Rajasthan to the Kalol Grinding Unit in Gujarat. The transition marks an increased use of electric mobility for long-haul cement transportation and is intended to lower the environmental impact of logistics operations.

The existing fleet operates on routes connecting the Sirohi plant with the Kalol Grinding Unit, Palanpur Unit and Surat Grinding Unit. JK Lakshmi Cement is working with electric vehicle logistics providers SwitchLabs and Billion E to support fleet deployment and manage transportation requirements across these routes.

The company expects the planned expansion to increase the use of electric mobility throughout its logistics network for moving cement and clinker. Chairperson and Managing Director Vinita Singhania said the programme reflected the integration of sustainable practices with the company’s focus on long-term business efficiency, while describing the Sirohi–Kalol transition as an important step in its wider decarbonisation strategy.

The EV programme forms part of JK Lakshmi Cement’s green logistics and sustainability roadmap, alongside initiatives to improve efficiency and reduce emissions across its value chain. The company has set a long-term target of achieving net-zero emissions by 2047. It is part of the JK Organisation and operates integrated cement plants in Rajasthan and Chhattisgarh, along with grinding units in Gujarat, Haryana and Odisha. The company has an annual turnover of more than Rs. 60 bn, combined cement capacity of approximately 18 mn t per annum and a target to raise capacity to 30 mn t by 2030. Its portfolio includes ready-mix concrete, gypsum plaster, wall putty, primer, adhesives and fly ash blocks.

Concrete

Martin Engineering Appoints Ashwini Khunte as India General Manager

Published

11 hours ago

October 30, 2026

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Martin Engineering names Ashwini Khunte India General Manager to strengthen operations and drive growth across key bulk material handling sectors.

Pune

Martin Engineering, a global provider of bulk material handling solutions, has appointed Ashwini Khunte as General Manager of its India business, strengthening its leadership as the company expands its presence across the country’s cement, mining, steel, power and infrastructure sectors.

Khunte brings more than a decade of experience with Martin Engineering, having joined its Indian operations in 2013 as a Design Engineer, shortly after the company established its presence in the country in 2012.

A mechanical engineer by qualification, she spent her initial five years developing bulk material handling solutions in collaboration with the company’s operations team. During this period, she gained extensive experience addressing operational challenges in the steel, cement and coal industries. She subsequently moved into project engineering, managing major engineering, procurement and construction (EPC) and original equipment manufacturer (OEM) projects from initial enquiry to commissioning. Her responsibilities later expanded to overseeing Martin Engineering’s conveyor product portfolio in India, involving customer engagement, technical presentations and site visits across heavy industries.

In 2024, Khunte was promoted to Head of Sales & Marketing for the company’s Europe, Middle East, Africa and India (EMEAI) region. The position broadened her international market exposure and strengthened her strategic and commercial leadership capabilities.

Commenting on her appointment, Ashwini Khunte, General Manager, Martin Engineering India, said: “India represents a tremendous opportunity for Martin Engineering. The country’s continued investment in cement, mining, steel, power and infrastructure is creating increasing demand for safer, cleaner and more productive bulk material handling, and that’s exactly what we do. My priority will be to build on the strong foundations already established in India, while continuing to develop our people, strengthen customer relationships and bring practical solutions to the challenges faced by our industry.”

Robert Whetstone, Area Vice President – EMEAI, Martin Engineering, highlighted Khunte’s technical expertise, market understanding and leadership experience.

“Ashwini brings an exceptional combination of technical understanding, customer knowledge and commercial leadership. She has grown as Martin Engineering has grown, and has consistently demonstrated outstanding capability to transform her expertise into practical solutions. Her knowledge of the Indian market, together with her international experience, makes her ideally suited to lead our India business through its next stage of growth for years to come.”

Since establishing its Indian business in 2012, Martin Engineering has expanded its local workforce, manufacturing capabilities and dealership network. The company supplies conveyor products, transfer point solutions, material flow aids, training and technical support to bulk material handling industries. Khunte’s appointment positions the company to further strengthen customer relationships and expand its solutions portfolio in India’s growing industrial and infrastructure markets.

Concrete

CII Calls for Greater Alternative Fuel Use in Cement Industry

Published

1 day ago

October 29, 2026

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The Confederation of Indian Industry (CII), through its Green Business Centre and Energy Efficiency Council, inaugurated the 16th Conference on Alternative Fuel and Raw Material Usage (AFR) in Goa on 27 October 2026. The two-day conference brought together more than 350 industry leaders, policymakers, waste management experts and technology providers to explore strategies for accelerating alternative fuel adoption in India’s cement industry.

Held under the theme ‘Preparation for Net-Zero: Alternative Fuels & Raw Material in Cement Manufacturing’, the conference focused on reducing dependence on conventional fuels, improving waste utilisation and strengthening circular economy practices across cement manufacturing operations.

E R Raj Narayanan, Chairman, AFR Conference 2026, and Business Head and Chief Manufacturing Officer, UltraTech Cement, highlighted the industry’s progress in alternative fuel adoption. He emphasised the need to scale implementation, strengthen supply chains and extend circularity beyond fuel substitution to alternative raw materials through technological innovation and industry collaboration.

Harish Adconkar, Managing Director, Goa Waste Management Corporation, highlighted Goa’s progress in scientific waste management and refuse-derived fuel (RDF) production. He stated that approximately 765,000 tonnes of RDF had been supplied to cement plants, contributing to an estimated displacement of 320,000–560,000 tonnes of coal. He emphasised the importance of consistent RDF offtake and stronger coordination between urban local bodies, waste management agencies and cement manufacturers.

Dr L P Singh, Director General, National Council for Cement and Building Materials, identified AFR as an important opportunity for decarbonisation and resource efficiency. Drawing parallels with the industry’s successful utilisation of fly ash, he stressed the need to address quality, technological and economic challenges to expand alternative fuel adoption.

Dr Sharad P Kale, Special Advisor to the Chief Minister of Goa and former Head of Technology Transfer and Collaboration at BARC, emphasised treating waste as a resource. He highlighted decentralised biodegradable waste processing, reduced food waste and improved resource recovery as essential measures for minimising landfill dependence.

Kiran Ananth, Executive Director, Energy Efficiency, Renewable Energy and Green Entrepreneurship, CII-Green Business Centre, noted that India’s cement production reached approximately 491 million tonnes in FY2025-26, while the industry’s thermal substitution rate (TSR) stood at 7.5 per cent, with around 7 million tonnes of alternative fuels utilised annually.

He added that the industry had invested over Rs 12 billion in co-processing infrastructure during the past six years. Improving RDF supply reliability and quality assurance would be crucial to maximising the utilisation of existing infrastructure and accelerating industrial decarbonisation.

The conference also featured discussions on advanced AFR co-processing technologies, waste pre-processing solutions and industrial best practices for improving fuel substitution and resource recovery.

A publication titled ‘From Waste to Kiln: Scaling the Use of MSW-Derived RDF in Indian Cement Plants’ was launched during the inaugural session. The report identified inconsistent RDF supply and quality as major barriers to achieving higher thermal substitution rates.

According to the publication, many cement kilns already possess the technical capability to achieve higher alternative fuel substitution. However, variations in RDF availability, moisture content, particle size and calorific value continue to limit utilisation. The report emphasised the need to strengthen waste segregation, pre-processing and aggregation systems to establish reliable RDF supply chains.

The conference’s second-day agenda includes discussions on innovative domestic and industrial waste management solutions, alternative raw materials for low-carbon cement and strategies to increase alternative fuel utilisation across India’s cement manufacturing sector.