Concrete

Material grinding is the largest electrical energy consumer in cement

Published

4 years ago

December 21, 2021

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Indian cement plants are at par with global cement industry in adoption of latest energy efficient technologies such as VRM, roller press in semi-finish and finish mode, believes Dr Bibekananda Mohapatra, Director General- National Council for Cement and Building Materials (NCCBM).

Indian cement plants are at par with global cement industry in adoption of latest energy efficient technologies such as VRM, roller press in semi-finish and finish mode, believes Dr Bibekananda Mohapatra, Director General- National Council for Cement and Building Materials (NCCBM).

Today, the requirement for the cement industry is to reduce power consumption and make the grinding process more energy efficient. Please share your views on how this can be achieved.

Material grinding is the largest electrical energy consumer in cement manufacture. For raw material grinding, the most preferred energy efficient technologies are Vertical Roller Mill (VRM), roller press with ball mill and roller press in finish mode. For coal grinding, VRM is the most energy efficiency technology. VRM is most preferred for using different type of fuels like coal, petcoke etc.

The introduction of an external re-circulation system for material, adjustable louvre ring, latest generation classifier, vortex rectifier, thin liners for ball mill, use of Computational Fluid Dynamics (CFD) to improve classification efficiency, multi-drive systems, secondary classification in the grid cone, installation of high-efficiency fans, the use of slide gates instead of dampers for major fans with Variable Frequency Drives (VFD) and modification of mill body in VRM to improve the air and material trajectories are examples of such changes which increase throughput and improve energy efficiency.

What are the latest energy efficient grinding/technologies/solutions that could benefit Indian cement companies in achieving energy efficiencies?

There are several energy-efficient grinding technologies/solutions available in grinding. Some of them are ceramic grinding media for mono-chamber ball mills, thin liners for ball mills and online particle size distribution analyser for cement mills. In (VRM) grit cone water injection concept can reduce the water consumption by up to 50 per cent and stabilise the grinding bed with less vibrations. Moreover, feeding solutions like rotary feeder, sandwich sealing system for clinker/slag mills results in less wear rate. Comparing different grinding systems, high pressure grinding rolls are at par in energy efficiency as compared to VRMs for grinding purpose. In VRMs, recent development in support rollers is also providing grinding force enabling high energy efficiency. Advancements in VRM main drive gear box is leading to lower cooling requirement and reduction in energy loss. Reduction in mills pressure drop, optimisation of grinding media in ball mills, separator fan volume loading, addition of grinding aids are some of the optimisation measures adopted by cement plants as seen in recent PAT cycles. Some high energy efficient plants have already achieved overall specific electrical energy consumption of 63-65 kWh/t cement. It is anticipated that with the improvements in motor efficiencies, fan efficiencies, implementation of above mentioned technologies and innovations, there is a scope for further electrical energy savings in grinding section.

How is the adoption level of the latest grinding techniques in India as compared to the global cement industry?

Indian cement plants are at par with global cement industry in adoption of latest energy efficient technologies such as VRM, roller press in semi-finish and finish mode. The specific power consumption of grinding section of a cement plant depends on various factors such as type of grinding technology adopted, type of cement produced, fineness requirement, clinker/additives characteristics etc. While it is not possible to trace reduction in specific energy consumption of grinding section over the decades, however, for the Indian cement industry as a whole, the average specific electrical energy consumption for complete plant was around 122 kWh/t of cement in 1960 and started decreasing in late 80’s due to technology change in large cement plants to present level of average of 82.5 kWh/t of cement. The best achieved specific energy consumption for integrated cement plant in India is 63 kWh/t of cement when compared to global best achieved specific energy consumption of 65 kWh/t of cement in Japan.

How have we evolved in terms of innovation in grinding mills at cement plants? What are the latest developments observed in this area?

Innovation is the need of the hour. Grinding technology suppliers are also working consistently in this direction. Some of the innovative grinding technologies are:

Beta-mill: This mill works on the pressure grinding principle. By having defined feeding velocity, material height and width, a defined layer of material is fed to the pressure transaction zone (grinding zone). Energy savings of up to 30 per cent for mill motor as compared to Roller Press and up to 70 per cent as compared to ball mills is possible.

Ultrasonic comminution: Latest development in comminution is based on the application of ultrasonic energy. Ultrasonic comminution efficiently transfers the energy needed for crushing to the raw material, by means of acoustic ultrasonic pulses that are generated by two counter-rotating disks with special aerodynamic surfaces. The small-pulse durations exert pressure waves that pulverize the particles.

Microwave comminution: Grinding is very energy intensive process. Typically, only 1 per cent of the energy input is used to create new surfaces, the rest is turned into noise and heat. Now, prior to mechanically grinding the material, microwaves can be used to selectively heat parts of the rock, causing them to fracture along grain boundaries. This significantly reduces grinding power when the microwave treated material enters into the mill.

Applying ultrasonic field in a roller -press mill: The required energy consumption for grinding is significantly reduced by careful application of an ultrasonic field in the grinding zone. It is also expected to prolong the life of mechanical components. A lower stress on the shafts and a reduction of the required torque can be observed. The lower mechanical stress should also cause less abrasive wear on the rolls. Experimental results obtained by using ultrasound to enhance the performance of a roller-press mill are very encouraging. An experiment was carried out for coal grinding in which the energy consumption was as low as 3 kWh/t of material when compared to 20 kWh/t of material in hammer mills.

Further investigations are required for possible implementation of the above technologies in the cement industry.

Concrete

JSW Cement Commissions Nagaur Plant, Enters North India

New Rajasthan unit boosts capacity to 24.1 MTPA and expands reach

Published

17 hours ago

March 30, 2026

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JSW Cement has strengthened its national presence by commencing production at its greenfield integrated cement plant in Nagaur, Rajasthan, marking its entry into the north Indian market.

With this commissioning, the company’s installed grinding capacity has increased to 24.1 MTPA, while total clinker capacity, including its joint venture operations, stands at 9.74 MTPA.

The Nagaur facility comprises a 3.30 MTPA clinkerisation unit and a 2.50 MTPA cement grinding unit, with an additional 1.00 MTPA grinding capacity currently under development. Strategically located, the plant is positioned to serve high-growth markets across Rajasthan, Haryana, Punjab and the NCR.

The project has been funded through a mix of equity and long-term debt, with Rs 800 crore allocated from IPO proceeds towards part-financing the unit.

Parth Jindal, Managing Director, JSW Cement, stated that the commissioning marks a key milestone in the company’s ambition to become a pan-India player. He added that the project was completed within 21 months and positions the company to achieve its targeted capacity of 41.85 MTPA by FY29.

Nilesh Narwekar, CEO, JSW Cement, highlighted that the expansion aligns with the company’s strategy to tap into rapidly growing northern markets driven by infrastructure development. He noted that the company remains focused on delivering high-quality, eco-friendly cement solutions while progressing towards its long-term capacity goal of 60 MTPA.

The Nagaur plant has been designed with sustainability features, including co-processing of alternative fuels and a 7 km overland belt conveyor for limestone transport to reduce road emissions. The facility will also incorporate a 16 MW Waste Heat Recovery System to improve energy efficiency and lower its carbon footprint.

JSW Cement, part of the JSW Group, operates across the building materials value chain and currently has eight plants across India, along with a clinker unit in the UAE through its joint venture.

Concrete

Cement Prices Likely To Rise As Petcoke Costs Increase

Nuvama warns input costs may lift prices by early April 2026

Published

4 days ago

March 27, 2026

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A report by Nuvama Wealth Management said cement prices in India could rise by the end of March or early April 2026 as producers face higher input costs linked to crude oil. The report identified rising petroleum coke and packaging material costs as principal drivers of upward pressure on production expenses. Petroleum coke, a fuel used in cement manufacturing, rose by about 13 per tonne (t) in US dollar terms in February 2026, a change that could be passed on to buyers. Producers may adjust prices later in the quarter to protect margins.

Cement demand remained stable during February and March 2026, supported by ongoing construction and infrastructure activity, and earlier price increases on non-trade sales were largely reversed by the end of February. Retail prices remained broadly steady through March in most regions. The persistence of demand may allow firms to manage price adjustments rather than apply uniform increases. Market responses will vary by region and logistical cost pressures.

Nuvama said that stock performance of cement companies will likely be influenced by the path of cement prices and petroleum coke costs in the coming weeks. Rising input costs including crude linked fuels and packaging may squeeze profit margins and prompt firms to monitor pricing and demand closely. The balance between input inflation and end demand will determine whether companies absorb costs or transfer them to customers. Analysts will watch forthcoming quarterly results for evidence of margin pressure or successful cost pass through.

Government capital expenditure showed moderation, with overall capex declining 24 per cent year-on-year to around Rs 2 trillion (Rs 2 tn) in January 2026 and cumulative capex from April 2025 to January 2026 at about Rs 20 trillion (Rs 20 tn), up eight per cent year-on-year. The report noted that real estate launches fell 44 per cent year-on-year in January 2026, and overall healthy demand could still be offset by rising crude linked input costs that may push cement prices higher by late March or early April 2026.

Concrete

IIT Guwahati Develops Radiation-Resistant Cement Mortar

Modified mortar offers structural strength and radiation shielding

Published

4 days ago

March 27, 2026

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Researchers at the Indian Institute of Technology Guwahati (IIT Guwahati) have developed a cement mortar that is stronger, more durable and more effective at blocking harmful radiation for nuclear facilities. The modified mortar is designed to act as both a structural component and a radiation shielding barrier by increasing density and durability to limit radiation penetration. Concrete made with the enhanced mortar is expected to reduce the risk of radiation leakage and to support protective structures over extended periods.

To achieve this, the team incorporated four types of microparticles into the cement mortar: boron oxide, lead oxide, bismuth oxide and tungsten oxide. These microparticles were added in small quantities to assess their impact on compressive strength after 28 days and on the material’s ability to shield mixed radiation fields comprising gamma rays and neutrons. The study reported distinct effects for each microparticle, indicating trade-offs between mechanical strength, workability and radiation attenuation.

Professor Hrishikesh Sharma of the Department of Civil Engineering at IIT Guwahati said the safety of nuclear infrastructure depends on the performance of containment materials under extreme mechanical and radiation environments and that the study showed microparticle modifications can improve structural integrity and shielding. The research offers a framework for developing cement-based materials for nuclear power plants, small modular reactors and medical radiation facilities by enhancing resistance to heat, structural loads and radiation. The study was published in Materials and Structures and was co-authored by Professor Sharma, research scholar Sanchit Saxena and Dr Suman Kumar of CSIR-Central Building Research Institute, Roorkee.

Future work will scale up the developed mortar to a full concrete mix design, conduct structural-level testing of reinforced concrete elements and optimise microparticle dosage to balance mechanical strength, workability, durability and shielding performance. The team is seeking collaborations with nuclear energy agencies, material manufacturers and infrastructure firms for real-world testing and pilot applications. These steps aim to validate performance under simulated field conditions and support safer, more resilient nuclear infrastructure.