Concrete

The future shall demand less energy intensive greener cements

Published

4 years ago

June 21, 2022

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Dr Sujit Ghosh, Executive Director – New Product and R&D, Dalmia Cement (Bharat), discusses the alternative raw materials that can be used in the production of cement and its impact on carbon emissions while underscoring the major challenges faced in using other cementitious materials.

What are the core raw materials used in the production of cement?

The core raw materials used in the production of cement are limestone (calcium carbonate) and clay (a source of silica). First, the limestone is roasted/calcined to create activated lime (CaO) in a calciner and then the activated lime along with siliceous clay is proportioned along with some other minor ingredients into a raw mix design and charged inside a kiln to form cement clinker; which is basically made of complex compounds of calcium-silica-oxides primarily, which when mixed with water, reacts, to form a cementitious gel paste that binds all aggregates together and when dried up provides strength to the concrete/plaster, made with cement and the aggregates.

Limestone (calcium carbonate) and clay (silica), which are both available in nature, are inert materials. Only when they are heat-treated at temperatures above 900^oC, they become activated lime (CaO) and activated/amorphous silica (SiO₂), and fuse inside the cement kiln in liquid form to form complex calcium-silica-oxides, that is cement or cement clinker.

What are the alternative raw materials that can be used in the production of cement? How does that impact the process of production?

As explained in the previous paragraph, any activated lime (CaO) and/or activated/amorphous silica (SiO₂), could be potential sources of cementitious material. These could be alternative raw materials for cement production. Thus far, the most widely found and used sources of alternative materials are primarily ‘fly ash’ and ‘blast furnace slag’. Fly ash is a waste product from the burning of coal (as in a thermal power plant etc). It primarily contains amorphous/activated silica (SiO₂), but very little active lime (CaO) in the Indian context. So, it is not reactive on its own, it needs activated lime (CaO) to become cementitious – which is available from cement clinker, when the two are co-processed in a cement manufacturing plant. Blast furnace slag likewise is a waste product from the steel manufacturing process and does contain some activated silica and activated lime, but again, not in the proportion/concentration to itself become cementitious. It also has to be co-processed with a cement clinker in a cement manufacturing plant. Overall, these alternative or supplementary cementitious materials, which are other industry wastes, due to the need for co-processing with cement clinker, may add some costs to the production process, but since the use of such alternative raw materials, reduces the dependence on highly energy-intensive clinker, they are welcome by the cement manufacturing fraternity, that helps lower the carbon footprint of production. These cements are called ‘blended cements’ – either fly ash blended (popularly known as PPC) or slag blended (popularly known as PSC) or fly ash + slag blended (popularly known as PCC).

How can the cost of production be reduced by using alternative or supplementary raw materials in cement production?

Since the use of alternative / supplementary cementitious materials has been prevalent in the world and in India, for blended cement production, for the last couple of decades, the demand for such other industry wastes (primarily from thermal power plant or steel plant) has been increasing steadily. This has led to a steep increase in prices for these industry wastes (mainly slags from steel plants) which otherwise were previously dumped in landfills, by opportunistic players and profiteering groups. Also, since steel plants and thermal power plants are not co-located with cement plants geographically, transportation costs of such bulky waste materials have also been increasing. Cost of blended cement production has to reduce or at least maintain at par, as well as, at the same time assist the nation in beneficially getting rid of other-industry-wastes. Cement players can do justice to climate-change by producing less energy intensive blended cements that are in no way inferior in quality to pure-clinker cements. Transport subsidies should also be provided to cement manufacturers by the government as well as at the same time try and administer some polluter-to-pay mechanism (so that these wastes are not conveniently dumped away in nearby landfills by the relevant industries).

–Kanika Mathur

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CII Calls for Greater Alternative Fuel Use in Cement Industry

Published

16 hours 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.

Concrete

Sameera Group Enters Industrial and Logistics Real Estate

Rs. 1.5 bn project to support manufacturing and supply-chain firms

Published

2 days ago

October 28, 2026

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Sameera Group has entered the industrial and logistics real estate segment with a 450,000 sq ft development in Sriperumbudur, Chennai. The group will invest Rs. 1.5 bn in the project, expanding beyond residential plotted developments into business-to-business real estate.

The proposed park will serve light manufacturing, e-commerce, third-party logistics and other supply-chain businesses. Building plan approvals have been secured, with construction expected to begin shortly. The development is scheduled to become operational within 12 to 15 months.

Sameera Group Managing Director and Chief Executive Officer Jayakumar Murugesan said the project marked the next stage of the company’s growth after nearly four decades in land acquisition and real estate development. He attributed the choice of Sriperumbudur to its industrial activity and growth prospects.

The Grade A development will include internal movement routes and shared infrastructure for modern manufacturing and logistics operations. The group is pursuing Indian Green Building Council (IGBC) Platinum certification and plans to provide rooftop solar readiness, rainwater harvesting, wastewater recycling, energy and water monitoring, and electric vehicle charging facilities.

The project is being developed amid increased demand for industrial and warehousing space in Chennai. Knight Frank’s India Warehousing Market Report 2026 recorded 8.3 mn sq ft of warehousing transactions in the city during 2025, up 42 per cent from the previous year, with manufacturing accounting for 59 per cent of demand. The Sriperumbudur-Oragadam cluster contributed 77 per cent of transactions.

Sameera Group plans to develop 5 to 6 mn sq ft across a larger industrial and logistics portfolio over the next five years, involving an estimated investment of Rs. 18 bn. Land has been acquired for projects in Chennai, Hosur and Bengaluru. Established in 1982, the group has developed more than 900 acres, sold over 13,700 residential plots, and currently has 35 projects under development and 28 in its pipeline.

Concrete

UltraTech Cement Expands in Andhra Pradesh with Rs. 26.5 bn

Petnikota plant adds 3.6 MTPA cement dispatch capacity

Published

7 days ago

October 23, 2026

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UltraTech Cement has expanded its manufacturing footprint in Andhra Pradesh with the commissioning of Petnikota Cement Works, an integrated cement plant built with an investment of around Rs. 26.5 bn. The facility is located in Petnikota village in Kolimigundla mandal of Nandyal district, in the Rayalaseema region.

Construction of the plant began in May 2025. The facility has a clinkerisation capacity of 3.3 MTPA and a cement dispatch capacity of 3.6 MTPA, strengthening the company’s production and distribution presence in the State.

The plant is expected to provide direct employment to 650 people and indirect employment to another 2,000. It has been designed to operate entirely on green energy and does not have a captive thermal power plant. The project also uses no groundwater, according to information released by the Andhra Pradesh Government.

Nara Lokesh, Andhra Pradesh Minister for Information Technology, said in the release that the facility was taken from groundbreaking to commissioning in 14 months. He described the project as a state-of-the-art addition to the company’s operations in the State and said it would create 2,650 direct and indirect employment opportunities.

Petnikota Cement Works adds to UltraTech Cement’s manufacturing capacity in Andhra Pradesh while supporting industrial activity in Nandyal district. The plant’s energy design and stated groundwater-use policy are also intended to reduce the environmental impact of its operations. The company has identified the facility as part of its continuing capacity expansion in the Indian cement market.