Concrete

Material grinding is the largest electrical energy consumer in cement

Published

5 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

Cement Makers’ Margins To Fall Rs 50-75 Per Tonne Amid West Asia Conflict

Crisil Sees Margins Easing Despite Steady Demand

Published

1 week ago

July 29, 2026

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Crisil said operating margins of Indian cement manufacturers are expected to decline by Rs 50-75 per tonne (t) this fiscal to Rs 925-950 per t due to higher input costs triggered by the West Asia conflict. The analysis covered 18 cement companies accounting for nearly 90 per cent of India’s domestic cement capacity and noted margins had improved sharply to around Rs 1,000 per t in fiscal 2026.

Crisil noted that the reduction would be driven mainly by higher power and fuel costs, which account for about 30 per cent of total costs, as petcoke and imported coal prices have surged amid geopolitical uncertainties. Freight costs, which account for about a quarter of total costs, are also expected to remain elevated because of higher diesel prices. The impact on profitability is likely to be more pronounced in the first half of the fiscal year before easing commodity prices moderate cost pressures later.

The rating agency said steady domestic demand and strong balance sheets should keep credit profiles stable despite the moderation in margins. Green energy currently accounts for 35-40 per cent of the sector’s total electricity consumption and is expected to partly cushion higher energy costs. Operating cash flows are likely to remain resilient, supported by projected 6-7 per cent growth in cement demand this fiscal.

Crisil highlighted that demand growth will be driven primarily by infrastructure spending, which meets about one-third of sector consumption, and by a nearly 18 per cent higher budgetary allocation for core ministries that should support project execution. Weaker rural housing demand amid pressure on agricultural incomes from a possible below-average monsoon may be offset by improved urban housing demand supported by favourable home-loan rates and a strong pipeline of Pradhan Mantri Awas Yojana-Urban projects. Ongoing capacity additions will keep capital expenditure elevated and may lift net debt to EBITDA to between 1.2 and 1.4 times from around 1.0 time last fiscal, though ratios are expected to remain healthy.

Concrete

UltraTech Board Approves Rs 50 bn Fundraise Via NCDs

Company to issue half a million debentures for expansion plan

Published

1 week ago

July 28, 2026

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UltraTech Cement’s board of directors has approved raising Rs 5,000 crore (Rs 50 bn) through non?convertible debentures issued in rupees.

The finance committee cleared a proposal to issue up to 500,000 fully paid, unsecured, listed, rated, redeemable, rupee?denominated, non?convertible, non?cumulative debentures of Rs 1 lakh each (Rs 0.1 mn each), aggregating to the Rs 5,000 crore programme.

As of June 2026 the firm reported net debt of Rs 15,875 crore (Rs 158.75 bn) and said its capacity expansion projects under execution are backed by capital expenditure of about Rs 17,000 crore (Rs 170 bn) over the next two to two?and?a?half years.

UltraTech spent Rs 9,500 crore (Rs 95 bn) on capital expenditure in financial year 2026 and in April the group crossed 200.1 mn tonnes per annum of domestic grey cement capacity and 205.5 mn tonnes per annum of global capacity.

The chief financial officer indicated the company would take consolidated capacity beyond 242 mn tonnes per annum, with grey cement capacity reaching 212.7 mn tonnes per annum by the end of financial year 2027. He noted the net debt?to?earnings before interest, taxes, depreciation and amortisation ratio stood at 0.87 times as of June 2026 and the company was confident of ending financial year 2027 with the ratio below one time.

In the first quarter of financial year 2026?27 UltraTech’s net profit attributable to owners rose 16.8 per cent year?on?year to Rs 2,599.3 crore (Rs 25.993 bn) and revenue from operations increased 15.9 per cent to Rs 24,648.20 crore (Rs 246.482 bn). The board approval is expected to complement internal cash flows as the company advances its expansion programme.

Concrete

Lokesh Lays Stone For Rs 31 Billion Cement Unit In Kadapa

Line-2 expansion to make Kadapa a major cement hub

Published

2 weeks ago

July 20, 2026

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Andhra Pradesh Education and IT Minister Nara Lokesh on Wednesday laid the foundation stone for the Line-2 expansion of Dalmia Bharat Cement at Chinnakomerla village in Mylavaram Mandal in Kadapa district. The project carries an investment of Rs 31 billion (bn) and is slated for completion by the third quarter of the financial year 2028. The expansion is intended to boost industrial growth and employment generation across the Rayalaseema region.

Once commissioned, the Kadapa facility will become Dalmia Bharat’s largest integrated cement manufacturing ecosystem in southern India, creating over 1,000 direct and indirect jobs and opening new business avenues for regional micro, small and medium enterprises and transport operators. Lokesh said the expansion signalled growing corporate confidence in the state and reflected the practical ease of doing business that secured repeat investment.

He placed the project within the government’s wider economic targets and recalled the Yuvagalam padayatra commitment to generate two million (mn) jobs within five years, noting that the state would cultivate talent while industry created opportunities. Lokesh highlighted Andhra Pradesh’s competitive pursuit of major manufacturing accounts, mentioning past successes and a personal initiative to engage global investors when persuading them to anchor expansion in the state.

The plant will leverage Kadapa’s abundant limestone reserves to scale production and sustainability. Clinker capacity is planned to rise from two point five million tonnes per annum (mn tpa) to six point one mn tpa, while overall cement output will increase from three point six mn tpa to nine point six mn tpa. The unit is designed to operate on over eighty per cent renewable energy and deploy waste heat recovery, zero liquid discharge, water recycling and advanced AI systems to optimise efficiency. Industries Minister TG Bharat, BC Welfare Minister S. Savitha and Jammalamadugu MLA C. Adinarayana Reddy attended the ceremony.