Economy & Market

Advances in Cement Analysis

Published

10 years ago

July 4, 2016

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Though Blaine analysis is a time tested method of measuring fineness of cement. Today Laser Diffraction technology scores over it mainly due to more accurate and real time measurement. Dr. Michael Caves, India ? Business Development Manager of Malvern AIMIL explains the advantages of laser based particle size analysers.

The final steps in cement manufacturing involve grinding (milling) and blending in order to produce the fine powder that is recognizable as cement. Every step in the manufacture of cement is checked by frequent physical tests, as is finished product, to ensure that it complies with all necessary specifications. Cement is ground to a particular fineness since the influence of particle size on the kinetics of cement hydration and development of strength is well known. A reduction in median particle size generally produces a higher compressive strength. Consequently the fineness of Portland cements has been increased over the years to improve properties such as higher early strengths. Nevertheless, other effects of increased fineness, such as higher water demands and more rapid heat generation in the concrete cannot be ignored. Despite the availability of instrumental methods of measuring particle size distributions, the classical method of air permeametry remains.

Understanding Blaine
Many plants control cement fineness using an air permeability apparatus to measure the Blaine number, a parameter related to the cement particle size. The Blaine surface area measurement has been used since the 1940s to determine cement quality and despite its longevity the limitations of this off-line technique are widely recognized. It is slow and suffers from poor reproducibility, which can lead to significant errors, including unnecessary or inaccurate changes to the classifier speed. Blaine analysis measures the specific surface area of a sample, the surface area per unit mass. Finer particle sizes have higher specific surface area: more area per unit mass, so Blaine is an indirect measure of particle size.

But, Blaine delivers just a single averaged figure. Figure 1 shows analysis of 2 cement samples using a Malvern Mastersizer Laser Diffraction system. Sample 2 contains more fines than sample 1 but also more coarse material. These two differences cancel each other out so average specific surface area remains the same, illustrating why two quite different samples can have the same Blaine. The more important question is ?do we need to know about the difference indicated by the particle size distribution??

Size Distribution Measurements
However two cement samples with identical Blaine figures can show different particle size distributions when measured by laser diffraction. Should we classify these two cements as different or the same?

For answers, we need to look at how the data are used. Cement manufacturers measure Blaine to quantify product quality. The hydration speed of cement particles is a function of particle size and determines the strength of the set cement. Generally, finer particles hydrate more quickly, giving greater strength, and within certain limits finer cement is better cement.

Returning to our samples, these materials will behave differently when used. Very fine cement particles, in the 2 – 3 micron range can cause exothermic cracking. Conversely particles over 50 microns may not hydrate, compromising product strength. Sample 1 contains less of both types of particles and consequently is a superior cement, even though Blaine ranks it the same as sample 2. So, the size distribution data are most certainly relevant.

Switching to laser diffraction
The practicalities of switching to laser diffraction are equally compelling. Laser diffraction, however, is fast and automated. In the lab this means greater productivity and better reproducibility. For processing it means on-line instrumentation and real-time measurement.

Malvern Mastersizer 3000 (Figure 2), which has a measurement range of 0.01 to 3500 microns, is an essential component of a high-quality cement laboratory. Finished products, as well as replacement material such as fly ash and blast furnace slag and fuels, have varying size distributions and so behavioral understanding and prediction requires Mastersizer analysis.

A vital element in successful laser diffraction particle size analysis is ensuring that samples are dispersed properly. In cement manufacture it is the primary particle size of a sample that is most usually the parameter of interest, rather than the size of any agglomerated material present. When using laser diffraction, samples can be dispersed and measured wet in the form of a suspension, or as dry powders. Dry dispersion, using dry compressed air, has a number of advantages, not least its obvious suitability for water sensitive material such as cement. It also avoids the need for solvent based dispersants and is rapid, thus increasing instrument productivity. The dry dispersion accessory, Aero S, available with Mastersizer 3000 has modular dispersion nozzles with different impaction surfaces. Keeping in mind that flow of abrasive material like cement for a prolonged period of time can cause damage to metal surfaces, there are options available for ceramic coated flow paths. It is worth highlighting the value of considering an analyzer that can switch easily between different samples with a minimum of fuss. Being able to change between different types of samples without fear of cross contamination, or to move simply or quickly from dry to wet measurement (or vice versa) as required, can make a real difference to analytical productivity, helping to maximize the return of investment in the system.

Finally, another important reason to switch to laser diffraction is the possibilities the technique offers for on-line analysis. Insitec systems deliver fully automated real-time analysis of cement particle size distribution from 0.1 to 2500 microns and can be configured to suit practically every process.

Conclusion
Whilst traditional Blaine measurements have served the cement industry well since the development of the Blaine method in the 1940s, the efficiency and quality of production of modern cements can be improved greatly by using Laser Diffraction technology. Efficient data acquisition, adaptable methods, and information-rich data explain the increasing use of the Malvern Mastersizer 3000 and Insitec range of systems in cement production around the world.

For more details, pls contact: Malvern Aimil Instruments Pvt. Ltd. Tel : 011-30810244 Fax : 011-26950011, Email : delhi@aimil.com

Economy & Market

TSR Will Define Which Cement Companies Win India’s Net-Zero Race

Published

3 days ago

April 27, 2026

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Jignesh Kundaria, Director and CEO, Fornnax Technology

India is simultaneously grappling with two crises: a mounting waste emergency and an urgent need to decarbonise its most carbon-intensive industries. The cement sector, the second-largest in the world and the backbone of the nation’s infrastructure ambitions, sits at the centre of both. It consumes enormous quantities of fossil fuel, and it has the technical capacity to consume something else entirely: the waste our cities cannot get rid of.

According to CPCB and NITI Aayog projections, India generates approximately 62.4 million tonnes of municipal solid waste annually, with that figure expected to reach 165 million tonnes by 2030. Much of this waste is energy-rich and non-recyclable. At the same time, cement kilns operate at material temperatures of approximately 1,450 degrees Celsius, with gas temperatures reaching 2,000 degrees. This high-temperature environment is ideal for co-processing, ensuring the complete thermal destruction of organic compounds without generating toxic residues. The physics are in our favour. The infrastructure is not.

Pre-processing is not the support act for co-processing. It is the main event. Get the particle size wrong, get the moisture wrong, get the calorific value wrong and your kiln thermal stability will suffer the consequences.

The Regulatory Push Is Real

The Solid Waste Management (SWM) Rules 2026 mandate that cement plants progressively replace solid fossil fuels with Refuse-Derived Fuel (RDF), starting at a 5 per cent baseline and scaling to 15 per cent within six years. NITI Aayog’s 2026 Roadmap for Cement Sector Decarbonisation targets 20 to 25 per cent Thermal Substitution Rate (TSR) by 2030. Beyond compliance, every tonne of coal replaced by RDF generates measurable carbon reductions which is monetisable under India’s emerging Carbon Credit Trading Scheme (CCTS). TSR is no longer a sustainability metric. It is a financial lever.

Yet our own field assessments across multiple Indian cement plants reveal a sobering reality: the primary barrier to scaling AFR adoption is not waste availability. It is the fragmented and under-engineered pre-processing ecosystem that sits between the waste and the kiln.

Why Indian Waste Is a Different Engineering Problem

Indian municipal solid waste is not the material that imported shredding equipment was designed for. Our waste streams frequently exceed 40 per cent to 50 per cent moisture content, particularly during monsoon cycles, saturated with abrasive inerts including sand, glass, and stone. Plants relying on imported OEM equipment face months of downtime awaiting proprietary spare parts. Machines built for segregated, low-moisture waste fail quickly and disrupt the entire pre-processing operation in Indian conditions.

The two most common failures we observe are what I call the biting teeth problem and the chewing teeth problem. Plants relying solely on a primary shredder reduce bulk waste to large fractions, but the output remains too coarse for stable kiln combustion. Others attempt to use a secondary shredder as a standalone unit without a primary stage to pre-size the feed, leading to catastrophic mechanical failure. When both stages are present but mismatched in throughput capacity, the system becomes a bottleneck. Achieving the 40 to 70 tonnes per hour required for meaningful coal displacement demands a precisely coordinated two-stage process.

Engineering a Made-in-India Answer

At Fornnax, our response to these challenges is grounded in one principle: Indian waste demands Indian engineering. Our systems are built around feedstock homogeneity, the holy grail of kiln stability. Consistent particle size and predictable calorific value are the foundation of stable kiln combustion. Without them, no TSR target is achievable at scale.

Our SR-MAX2500 Dual Shaft Primary Shredder (Hydraulic Drive) processes raw, baled, or loosely mixed MSW, C&I waste, bulky waste, and plastics, reducing them to approximately 150 mm fractions at throughputs of up to 40 tonnes per hour. The R-MAX 3300 Single Shaft Secondary Shredder (Hydraulic Drive), introduced in 2025, takes that primary output and produces RDF fractions in the 30 to 80 mm range at up to 30 tonnes per hour, specifically optimised for consistent kiln feeding. We have also introduced electric drive configurations under the SR-100 HD series, with capacities between 5 and 40 tonnes per hour, already operational at a leading Indian waste-processing facility.

Looking ahead, Fornnax is expanding its portfolio with the upcoming SR-MAX3600 Hydraulic Drive primary shredder at up to 70 tonnes per hour and the R-MAX2100 Hydraulic drive secondary shredder at up to 20 tonnes per hour, designed specifically for the large-scale throughput that higher TSR ambitions require.

The Investment Case Is Now

The 2070 Net-Zero target is not a distant goal for India’s cement sector. It starts today, with decisions being made on the plant floor.

The SWM Rules 2026 are already in effect, requiring cement plants to replace coal with RDF. Carbon credit markets are opening up, and coal prices are not going to get cheaper. Every tonne of coal a cement plant replaces with waste-derived fuel saves money on one side and generates carbon credit revenue on the other. Pre-processing infrastructure is no longer just a compliance requirement. It is a business investment with a measurable return.

The good news is that nothing is missing. The technology works. The waste is available in every Indian city. The government has provided the policy direction. The only thing standing between where the industry is today and where it needs to be is the commitment to build the right infrastructure.

The cement companies that move now will not just meet the regulations. They will be ahead of every competitor that waits.

About The Author

Jignesh Kundaria is the Director and CEO of Fornnax Technology. Over an experience spanning more than two decades in the recycling industry, he has established himself as one of India’s foremost voices on waste-to-fuel technology and alternative fuel infrastructure.

Concrete

WCA Welcomes SiloConnect as associate corporate member

Published

2 weeks ago

April 13, 2026

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The World Cement Association (WCA) has announced SiloConnect as its newest associate corporate member, expanding its network of technology providers supporting digitalisation in the cement industry. SiloConnect offers smart sensor technology that provides real-time visibility of cement inventory levels at customer silos, enabling producers to monitor stock remotely and plan deliveries more efficiently. The solution helps companies move from reactive to proactive logistics, improving delivery planning, operational efficiency and safety by reducing manual inspections. The technology is already used by major cement producers such as Holcim, Cemex and Heidelberg Materials and is deployed across more than 30 countries worldwide.

Concrete

TotalEnergies and Holcim Launch Floating Solar Plant in Belgium

Published

2 weeks ago

April 13, 2026

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TotalEnergies and Holcim have commissioned a floating solar power plant in Obourg, Belgium, built on a rehabilitated former chalk quarry that has been converted into a lake. The project has a generation capacity of 31 MW and produces around 30 GWh of renewable electricity annually, which will be used to power Holcim’s nearby industrial operations. The project is currently the largest floating solar installation in Europe dedicated entirely to industrial self-consumption. To ensure minimal impact on the surrounding landscape, more than 700 metres of horizontal directional drilling were used to connect the solar installation to the electrical substation. The project reflects ongoing collaboration between the two companies to support industrial decarbonisation through renewable energy solutions and innovative infrastructure development.