Concrete

Increasing Use of Supplementary Cementitious Materials

Published

1 year ago

October 19, 2023

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Jens Mose and John Terembula, Product Line Management, FLSmidth A/S, explore how cement manufacturers can utilise VRMs to reduce the clinker factor and meet their environmental targets, in the final part of this three-part series. You can find parts one and two in the August and September issues of Indian Cement Review.

OPTIMISING PARTICLE SIZE DISTRIBUTION
Experience has shown that practically every type of cement around the world can be – and is already being – produced in an OK MillTM.
While the particle size distribution (PSD) of the product is normally steeper in a VRM cement mill compared to a traditional ball mill, this can, to some extent, be modified by working with various parameters such as grinding pressure and dam ring height. The air flow and the separator speed are also used to customise the PSD curve to customer specific requirements.
However, as interest in greater utilisation of SCMs increases, cement manufacturers are keen to grind to an even steeper PSD curve to allow for the possibility of mixing more SCMs into the finished product.

THE ADVANTAGES OF VRMS FOR SCMS
When the VRM is designed specifically for grinding cement and cementitious materials, cement manufacturers experience better:

Efficiency: Lowest power consumption compared to other vertical roller mills on the market.
Reliability: The run factor is very high, > 95 per cent
Versatility: Rapid change between different feed compositions and the ability to grind a wide range of materials to very high Blaine or the lowest residues

The OK MillTM was designed with these priorities in mind, and has retained its original shape with a dual lobed roller surface and central grooved and bowl-shaped table design. As the only VRM in the market specifically designed for cement grinding, all rollers are active with each performing material bed compaction and de-aeration, and high-pressure grinding.
Sustainability is also a priority, which is why the mill is designed to require minimal water injection on the mill table, using an average 50 per cent less water than competing mill designs.

Maintenance is also a sustainability issue. Better to repair a part than replace it; better to be proactive than reactive. Predictive maintenance services aim to enable a higher level of proactivity, preventing unexpected downtime and reducing the cost of maintenance.
Over the last 20 years, in-situ rewelding or hard facing has become the standard maintenance practice for VRM, particularly for OK MillsTM with segmented wear liners that can tolerate repeated welding. Roller liner segments can be rewelded as many as 10 times or more and table segments 15 times or more. In order to improve its service capability for VRMs, FLSmidth works with welding services providers across the globe. We have also developed ceramic wear segments in an OK MillTM, which not only perform better but can also be recycled.

DIGITAL TOOLS FOR GREATER FLEXIBILITY
Digitalisation makes it easier to use SCMs and will enable further reductions in the clinker factor. The following are just a snapshot of the tools currently available; more are in development all the time:

Process control solutions give operators greater control over their mill operating parameters to optimise performance and ensure maximum efficiency.
Sensors continually monitor mill operation, enabling you to see any drop in stability as it happens and react swiftly.
Automated laboratories enable optimum quality control throughout the process.
Condition monitoring services and remote service support give you 24/7 access to expert assistance.

CONCLUSION
As the cement industry works to reduce its carbon footprint, investments have to be made in future-proof technologies capable of adapting to changing cement mixes and regulatory requirements. In the grinding process, cement manufacturers need a flexible, efficient system that is operated and maintained in an optimal manner. With the latest VRM technologies, advanced digital offerings and condition monitoring services, FLSmidth believes the industry is ready to achieve more widespread use of SCMs and achieve its carbon reduction goals.

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Concrete

Jefferies’ Optimism Fuels Cement Stock Rally

The industry is aiming price hikes of Rs 10-15 per bag in December.

Published

2 weeks ago

December 4, 2024

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Cement stocks surged over 5% on Monday, driven by Jefferies’ positive outlook on demand recovery, supported by increased government capital expenditure and favourable price trends.

JK Cement led the rally with a 5.3% jump, while UltraTech Cement rose 3.82%, making it the top performer on the Nifty 50. Dalmia Bharat and Grasim Industries gained over 3% each, with Shree Cement and Ambuja Cement adding 2.77% and 1.32%, respectively.

“Cement stocks have been consolidating without significant upward movement for over a year,” noted Vikas Jain, head of research at Reliance Securities. “The Jefferies report with positive price feedback prompted a revaluation of these stocks today.”

According to Jefferies, cement prices were stable in November, with earlier declines bottoming out. The industry is now targeting price hikes of Rs 10-15 per bag in December.

The brokerage highlighted moderate demand growth in October and November, with recovery expected to strengthen in the fourth quarter, supported by a revival in government infrastructure spending.
Analysts are optimistic about a stronger recovery in the latter half of FY25, driven by anticipated increases in government investments in infrastructure projects.
(ET)

Concrete

Steel Ministry Proposes 25% Safeguard Duty on Steel Imports

The duty aims to counter the impact of rising low-cost steel imports.

Published

2 weeks ago

December 4, 2024

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The Ministry of Steel has proposed a 25% safeguard duty on certain steel imports to address concerns raised by domestic producers. The proposal emerged during a meeting between Union Steel Minister H.D. Kumaraswamy and Commerce and Industry Minister Piyush Goyal in New Delhi, attended by senior officials and executives from leading steel companies like SAIL, Tata Steel, JSW Steel, and AMNS India.

Following the meeting, Goyal highlighted on X the importance of steel and metallurgical coke industries in India’s development, emphasising discussions on boosting production, improving quality, and enhancing global competitiveness. Kumaraswamy echoed the sentiment, pledging collaboration between ministries to create a business-friendly environment for domestic steelmakers.

The safeguard duty proposal aims to counter the impact of rising low-cost steel imports, particularly from free trade agreement (FTA) nations. Steel Secretary Sandeep Poundrik noted that 62% of steel imports currently enter at zero duty under FTAs, with imports rising to 5.51 million tonnes (MT) during April-September 2024-25, compared to 3.66 MT in the same period last year. Imports from China surged significantly, reaching 1.85 MT, up from 1.02 MT a year ago.

Industry experts, including think tank GTRI, have raised concerns about FTAs, highlighting cases where foreign producers partner with Indian firms to re-import steel at concessional rates. GTRI founder Ajay Srivastava also pointed to challenges like port delays and regulatory hurdles, which strain over 10,000 steel user units in India.

The government’s proposal reflects its commitment to supporting the domestic steel industry while addressing trade imbalances and promoting a self-reliant manufacturing sector.

(ET)

Concrete

India Imposes Anti-Dumping Duty on Solar Panel Aluminium Frames

Move boosts domestic aluminium industry, curbs low-cost imports

Published

2 weeks ago

December 4, 2024

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The Indian government has introduced anti-dumping duties on anodized aluminium frames for solar panels and modules imported from China, a move hailed by the Aluminium Association of India (AAI) as a significant step toward fostering a self-reliant aluminium sector.

The duties, effective for five years, aim to counter the influx of low-cost imports that have hindered domestic manufacturing. According to the Ministry of Finance, Chinese dumping has limited India’s ability to develop local production capabilities.

Ahead of Budget 2025, the aluminium industry has urged the government to introduce stronger trade protections. Key demands include raising import duties on primary and downstream aluminium products from 7.5% to 10% and imposing a uniform 7.5% duty on aluminium scrap to curb the influx of low-quality imports.

India’s heavy reliance on aluminium imports, which now account for 54% of the country’s demand, has resulted in an annual foreign exchange outflow of Rupees 562.91 billion. Scrap imports, doubling over the last decade, have surged to 1,825 KT in FY25, primarily sourced from China, the Middle East, the US, and the UK.

The AAI noted that while advanced economies like the US and China impose strict tariffs and restrictions to protect their aluminium industries, India has become the largest importer of aluminium scrap globally. This trend undermines local producers, who are urging robust measures to enhance the domestic aluminium ecosystem.

With India’s aluminium demand projected to reach 10 million tonnes by 2030, industry leaders emphasize the need for stronger policies to support local production and drive investments in capacity expansion. The anti-dumping duties on solar panel components, they say, are a vital first step in building a sustainable and competitive aluminium sector.