Concrete

Dawn of a Green Era

Published

2 years ago

January 12, 2024

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Vimal Kumar Jain, Director – Technical, HeidelbergCement India, discusses how his company has utilised technology to decarbonise the cement manufacturing process with the use of new-age methodologies.

HeidelbergCement India (HC India) produces world-class products under the brands Mycem and Zuari. HC India is a part of Heidelberg Materials, Germany, which is one of the world’s largest producers of building materials. Heidelberg Materials stands for competence and quality, in over 50 countries. HC India has four integrated cement plants, four grinding units and a terminal with an installed capacity of about 14 MTPA.
At the centre of our actions lies our responsibility for the environment. We are the front runner on the road to carbon neutrality and circular economy in the building materials industry. We are working on intelligent and sustainable building materials as well as solutions for the future.
We have taken green initiatives like water positivity, green power generation by installing a waste heat recovery system and solar power plant, NOx emission reduction system (SNCR), alternative fuel utilisation in place of fossil fuels, etc.

Municipal Solid Waste (MSW)
The production of cement requires a high degree of thermal energy. The traditional fuels used in the kilns are coal, oil, petroleum coke etc. The substitution of fossil fuels by alternative fuels in the production of cement clinker is having great importance for society and climate control because it conserves fossil fuel reserves and reduces greenhouse gas (GHG) emissions. We are aiming to maximise the usage of alternative fuels such as industrial wastes, plastics, used tires, biomass wastes and municipal wastes, thus replacing conventional fuels.
Disposal of MSW is a challenge for environment and climate control. Earlier, municipal waste was openly burned or land-filled, which generated greenhouse gas emissions and leachate from the landfilling sites induced secondary pollution. HC India has taken the challenge to co-process the municipal solid waste in kilns to reduce GHG emissions and conserve natural resources.
Co-processing of municipal waste needs special expertise and state-of-the-art technology for safe and environment friendly disposal. HeidelbergCement group has installed a municipal solid waste feeding system with a storage shed.
There are several challenges associated with using municipal waste in kilns. It is highly heterogeneous in nature, which makes it difficult to maintain kiln stability. The main issue is related to size and flowability of municipal waste. Flowability was a bigger issue during waste feeding, due to bigger size up to 300 mm and high moisture content (25-30 per cent) the material frequently stuck up at the hopper discharge chute. To improve this, the hopper chute has been modified and a new shredder machine installed.

This helps to reduce the size of municipal waste less than 50mm. This increases alternative fuel utilisation. A grab crane mechanised system was also installed to ensure continued waste feeding. This technology replaced the previous manual waste feeding system, which was not consistent.
Consistent quality and quantity of municipal waste in the vicinity of a cement plant is also a challenge to prepare suitable raw mix/fuel mix. We made agreements with local municipalities to ensure consistent continuous supply of waste. We have a dedicated lab for analysing alternative fuels. To increase Thermal Substitution Rate (TSR) and MSW utilisation, a shredder and grab crane
were installed.

NOx Emission Control Technology
The ‘clinkerisation’ process is the most important step of cement manufacturing, and the one which requires all our vigilance because of its possible environmental consequences as cement (clinkerisation) processes release nitrogen oxides ( NOx) emissions. In the cement industry normally, 95 per cent of NOx formed is nitric oxide (NO). This gas is colourless and is readily transformed into NO2 in air.

Thermal NOx Formation
Thermal NOx is formed at a temperature greater than about 1200°C by direct oxidation of atmospheric nitrogen. Since the flame temperature in cement rotary kilns is about 2000°C, a considerable amount of thermal NO is generated. The thermal reaction between oxygen and nitrogen to form NO takes place in the process.
NO formation increases rapidly with temperature and in the presence of excess oxygen. Factors affecting the concentration of NO in the kiln gases are:
• Flame temperature
• Flame shape
• Excess air rate
• Maximum material temperature
• Material retention time in burning zone
• Gas retention time in burning zone

Fuel NOx Formation

NOx also results from the oxidation of nitrogen compounds present in fuel, other than gaseous. The reaction normally takes place at relatively lower temperature, less than 1200°C.
Fuel NOx formation normally depends on:
• Nitrogen content in the fuel
• Volatile content in the fuel
• Oxygen level in the combustion zone
• Initial NO concentration in the combustion gas
• Temperature in the secondary combustion zone

Prompt NOx Formation
Prompt NOx is formed by fuel-derived radicals, such as CH reacting with N2 in hydrocarbon flames. The overall contribution of prompt NOx to total NO is relatively less.

Control Techniques
Typical NOx emission in older technologies can be as high as 1800 – 2000 mg/Nm3, while the average emission value in modern plants is around 1000 mg/Nm3. NOx emissions reduction from cement plants can be done in two methods.

Primary NOx Reduction methods
• Optimisation of clinker burning process.
• Automatic kiln control system or expert system.
• Use of low NOx burner to allow low primary air and to control flame flow pattern.
• Addition of water to the flame or fuel of the main burner.
• Staged combustion in precalciner.

In calciner staged combustion, fuel is first burned under reducing conditions to reduce NOx and then the remaining fuel burns under oxidising conditions to complete the combustion. Introduction of raw meal allows control of calciner temperature. Through these mechanisms, both fuel NOx and thermal NOx are controlled.

Secondary NOx Reduction Method
In the secondary reduction measure, a separate gas cleaning unit is added. Selective Non Catalytic Reduction (SNCR) system and this technology can reduce NOx up to 80 per cent. In this process NO reacts with NH3. The reagent typically NH3 or urea is injected into the kiln system at a location with an appropriate temperature window (870°C to 1100°C). The temperature is critical, at higher temperatures the reagents will form additional NOx whereas at lower temperatures the reactions proceed slowly, and substantial amounts of unreacted ammonia will escape.
HC India installed SNCR systems in their cement plants to reduce the NOX emissions to support UN SDG goals. Nox Emission reduced <700 mg/Nm3 by installing SNCR system.

The MIYAWAKI method
Air pollution is a global crisis and high concentrations of harmful gases and particles in our atmosphere negatively affect the health of humans, animals, and plants, and also cause global warming. Tree plantation is the natural remedy to control emissions, trees act as earth purification by absorbing toxic gases and releasing oxygen. We need to plant more trees to tackle global warming.

But the challenge lies in availability of space and growth of plants. The Miyawaki method is a solution for this challenge as these method plants grow rapidly and require less space.
In the 1980s, Dr Akira Miyawaki introduced a new and innovative reforestation approach in Japan with the challenge to restore indigenous ecosystem, and to maintain the global environment, including disaster prevention and greenhouse gas mitigation. The Miyawaki technique is a unique methodology proven to work worldwide, irrespective of the
soil’s agro climatic conditions. A completely chemical free forest in an organic way that sustains itself, supports local biodiversity, and attracts birds and insects.
Reconstitution of ‘indigenous forests by indigenous plants’ produces a rich, dense and efficient protective pioneer forest in 2-3 years. This type of planting resulted in quick production of multi layered forest, a soil rich with microbial activity like that of a normal primary forest. It’s a multi-layered green forest, maintenance free and 100 per cent organic with zero pesticides/ chemical fertilisers.
The Miyawaki planting method was executed at our colony with a total number of 2,700 plants comprising 31 different plant species. Saplings are planted closely together to promote growth. Around 5-6 saplings per square metre are recommended. This is to facilitate a natural forest pattern. Initially the soil is mixed with manures and irrigated at regular intervals. The plants utilise these resources in the beginning and once they are established, all the resources being given are stopped so that the plants could thrive on their own and survive.
The total land area is 0.5 acres (143m x 14m). It was basically an unused waste land with rocks, which is cleared off of all the pebbles, stones, plastic and other domestic waste. The land was dug up
one metre in depth and old soil was replaced with red soil, which was thoroughly mixed with paddy husk, vermicompost, red soil and coco peat in 1:1:1:1 ratio for 0.5 acre of land. Thereafter, 2,700 plants
were planted.

ABOUT THE AUTHOR:

Vimal Kumar Jain, Director – Technical, HeidelbergCement India, in his career spanning over 32 years, he has gained experience in operations and maintenance and project management from concept to commissioning, in the cement sector. He holds a mechanical engineering degree and a business & operations management diploma.

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Concrete

The primary high-power applications are fans and mills

Published

2 days ago

October 10, 2025

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Alex Nazareth, Whole-time Director and CEO, Innomotics India, explains how plants can achieve both cost competitiveness and sustainability by lowering emissions, reducing downtime and planning for significant power savings.

As one of the most energy-intensive industries, cement manufacturing faces growing pressure to optimise power consumption, reduce emissions and improve operational reliability. Technology providers like Innomotics India are enabling this transformation by combining advanced motors, AI-driven digital solutions and intelligent monitoring systems that enhance process stability and reduce energy costs. From severe duty motors built for extreme kiln environments to DigiMine AI solutions that optimise pyro and mill operations, Alex Nazareth, Whole-time Director and CEO, Innomotics India, explains how the company is helping cement plants achieve measurable energy savings while moving closer to their sustainability goals.

How does your Energy Performance Contracting model typically reduce power consumption in cement plants—e.g., MWh saved?
Our artificial intelligence-based DigiMine AI Pyro and Mill solutions developed specifically for the cement industry, supports our customers in improving their process stability, productivity and process efficiency. In Pyro, this is achieved by optimising fuel consumption (Coal / AFR), reducing Specific Heat Consumption and reduction in emissions (CO2, SOx and NOx) through continuous monitoring of thermodynamics in pyro and recommending set-points of crucial parameters in advance for maintaining stable operations.
Within the mill, this is achieved by improving throughput, reduce energy / power consumption and maintaining stable operations on a continuous basis. Our ROI-based value proposition captures the project KPIs like reduction of coal usage, increase of AFR, reduction of specific heat consumption (Kcal / Kg), reduction of specific power consumption (KWH / tonne), reduction of emissions, etc., by a specific percentage. This gives clarity to our customers to understand the investment vis-à-vis savings and estimate the recovery time of their investment, which typically is achieved within one year of DigiMine AI Pyro and Mill solutions implementation.

What role do digitalisation and motor monitoring play in overall plant energy optimisation?
Motors are being used extensively in cement production, and their monitoring play crucial role in ensuring continuous operation of applications. The monitoring system can automatically generate alerts for any anomaly / abnormalities in motor parameters, which allows plant team to take corrective actions and avoid any major equipment damage and breakdown. The alerts help maintenance team to plan maintenance schedule and related activity efficiently. Centralised and organised data gives overview to the engineers for day-to-day activities. Cement is amongst the top energy intensive industries in comparison to other industries. Hence, it becomes critically important to optimise efficiency, productivity and up-time of plant equipment. Motor monitoring and digitalisation plays a vital role in it. Monitoring and control of multiple applications and areas
within the plant or multiple plants becomes possible with digitalisation.
Digitalisation adds a layer on top of OT systems, bringing machine and process data onto a single interface. This solves the challenges such as system silo, different communications protocol, databases and most importantly, creates a common definition and measurement to plant KPIs. Relevant stakeholders, such as engineers, head of departments and plant heads, can see accurate information, analyse it and make better decisions with appropriate timing. In doing so, plant teams can take proactive actions before machine breakdown, enable better coordination during maintenance activities while improving operational efficiency and productivity.
Further using latest technologies like Artificial Intelligence can even assist operators in running their plant with minimal requirement of human intervention, which allows operators to utilise their time in focusing on more critical topics like analysing data to identify further improvements in operation.

Which of your high-efficiency IEC low-voltage motors deliver the best energy savings for cement mills or fans?
Innomotics India offers a range of IEC-compliant low-voltage motors engineered to deliver superior performance and energy savings, particularly for applications such as cement mills, large fans, and blowers. Innomotics has the complete range of IE4 motors from 0.37kW to 1000kW to meet the demands of cement industry. The IE5 range is also available for specific requirements.

Can safe area motors operate safely and efficiently in cement kiln environments?
Yes, safe area motors are designed to operate reliably in these environments without the risk of overheating. These motors have ingress protection that prevents dust, moisture ingress and can withstand mechanical stress. These motors are available in IE3 / IE4 efficiency classes thereby ensuring lower energy consumption during continuous operation. These motors comply with relevant Indian as well as international standards.

How do your SD Severe Duty motors contribute to lower emissions and lower cost in heavy duty cement applications?
Severe duty motors enhances energy efficiency and durability in demanding cement applications, directly contributing to lower emissions and operational costs. With high-efficiency ratings (such as IE3 or better), they reduce power consumption, minimising CO2 output from energy use. Their robust design handles extreme heat, dust and vibration—common in cement environments—ensuring reliable performance and fewer energy losses.
These motors also lower the total cost of ownership by reducing downtime, maintenance and replacement frequency. Their extended service life and minimal performance degradation help cement plants meet sustainability targets, comply with emissions regulations and improve overall energy management—all while keeping production consistent and cost-effective.

What pump, fan or compressor drive upgrades have shown approximately 60 per cent energy savings in industrial settings and can be replicated in cement plants?
In the cement industry, the primary high-power applications are fans and mills. Among these, fans have the greatest potential for energy savings. Examples, the pre-heater fan, bag house fan, and cooler fans. When there are variations in airflow or the need to maintain a constant pressure in a process, using a variable speed drive (VSD) system is a more effective option for starting and controlling these fans. This adaptive approach can lead to significant energy savings. For instance, vanes and dampers can remain open while the variable frequency drive and motor system manage airflow regulation efficiently.

Concrete

We conduct regular internal energy audits

Published

2 days ago

October 10, 2025

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Shaping the future of low-carbon cement production involves integrating renewables, digitalisation and innovative technologies. Uma Suryam, SVP and Head Manufacturing – Northern Region, Nuvoco Vistas, gives us a detailed account of how.

In an industry where energy consumption can account for a significant portion of operating costs, cement manufacturers are under increasing pressure to adopt sustainable practices without compromising efficiency. Nuvoco Vistas has taken a decisive step in this direction, leveraging digitalisation, renewable energy and innovative technologies to drive energy efficiency across its operations. In this exclusive conversation, Uma Suryam, SVP and Head Manufacturing – Northern Region, Nuvoco Vistas, shares its approach to energy management, challenges of modernising brownfield plants and its long-term roadmap to align efficiency with India’s net-zero vision.

How has your company improved energy efficiency over the past five years?
Over the past five years, we have prioritised energy conservation by enhancing operational efficiency and scaling up renewable energy adoption. Through strategic fuel mix optimisation, deployment of cleaner technologies, and greater integration of renewables, we have steadily reduced our environmental footprint while meeting energy needs sustainably.
Technological upgrades across our plants have further strengthened efficiency. These include advanced process control systems, enhanced trend analysis, grinding media optimisation and the integration of solar-powered utilities. Importantly, grid integration at our key plants has delivered significant cost savings and streamlined energy management.
A notable milestone has been the expansion of our solar power capacity and Waste Heat Recovery Systems (WHRS). Our solar power capacity has grown from 1.5 MW in FY 2021–22 to 5.5 MW, while our WHRS capacity has increased from 44.7 MW to 49 MW, underscoring our commitment to sustainable energy solutions.

What technologies or practices have shown the highest energy-saving potential in cement production?
One of our most significant achievements in advancing energy efficiency has been the successful commissioning of a 132 KV Grid Integration Project, which unified three of our major manufacturing units under a single power network. This milestone, enabled by a dedicated transmission line and a state-of-the-art Line-In Line-Out (LILO) substation, has transformed our energy management and operational capabilities.
With this integration, we have substantially reduced our contract demand, eliminated power disruptions, and enhanced operational continuity. Supported by an optical fibre network for real-time communication and automation, this project stands as a testament to our innovation-led manufacturing excellence and underscores Nuvoco’s vision of building a safer, smarter, and sustainable world.

What role does digitalisation play in achieving energy efficiency in your operations?
Digitalisation plays a transformative role in driving energy efficiency across our operations. At Nuvoco, we are leveraging cutting-edge technologies and advanced digital tools to enhance productivity, optimise energy consumption and strengthen our commitment to sustainability and employee safety.
We are developing AI-enabled dashboards to optimise WHRS and kiln operations, ensuring maximum efficiency. Additionally, our advanced AI models evaluate multiple operational parameters — including fuel pricing, moisture content and energy output — to identify the most cost-effective fuel combinations in real time. These initiatives are enabling data-driven decision-making, improving operational excellence and reducing our environmental footprint.

What is your long-term strategy for aligning energy efficiency with decarbonisation goals?
As part of India’s climate action agenda, the cement sector has laid out a clear decarbonisation roadmap to achieve net-zero CO2 emissions by 2070. At Nuvoco, we view this as both a responsibility and an opportunity to redefine the future of sustainable construction. Our long-term strategy focuses on aligning energy efficiency with decarbonisation goals by embracing innovative technologies, alternative raw materials and renewable energy solutions.
We are making strategic investments to scale up solar power installations and enhance our renewable energy mix significantly by 2028. These initiatives are a key part of our broader vision to reduce Scope 2 emissions and strengthen our contribution to India’s net-zero journey, while continuing to deliver innovative and sustainable solutions to our customers.

How do you measure and benchmark energy performance across different plants?
We adopt a comprehensive approach to measure and benchmark energy performance across our plants. Key metrics include Specific Heat Consumption (kCal/kg of clinker) and Specific Power Consumption (kWh/tonne of cement), which are continuously tracked against Best Available Technology (BAT) benchmarks, industry peers and global standards such as the WBCSD-CSI and CII benchmarks.
To ensure consistency and drive improvements, we conduct regular internal energy audits, leverage real-time dashboards and implement robust KPI tracking systems. These tools enable us to compare performance across plants effectively, identify optimisation opportunities and set actionable targets for energy efficiency and sustainability.

What are the key challenges in adopting energy-efficient equipment in brownfield cement plants?
Adopting energy-efficient technologies in brownfield cement plants presents a unique set of challenges due to the constraints of working within existing infrastructure. Firstly, the high capital expenditure and relatively long payback periods often require careful evaluation before investments are made. Additionally, integrating new technologies with legacy equipment can be complex, requiring significant customisation to ensure seamless compatibility and performance.
Another major challenge is minimising production disruptions during installation. Since brownfield plants are already operational, upgrades must be planned meticulously to avoid affecting output. In many cases, space constraints in older facilities add to the difficulty of accommodating advanced equipment without compromising existing layouts.
At Nuvoco, we address these challenges through a phased implementation approach, detailed project planning and by fostering a culture of innovation and collaboration across our plants. This helps us balance operational continuity with our commitment to driving energy efficiency and sustainability.

Concrete

Enlight Metals Supplies 3,200 Tonne of Steel for Navi Mumbai Airport

The airport is set to become Asia’s largest air connectivity hub.

Published

2 days ago

October 10, 2025

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Enlight Metals has supplied 3,200 metric tonne of steel for the newly inaugurated Navi Mumbai International Airport, marking a major contribution to one of India’s largest infrastructure projects and reinforcing the company’s commitment to supporting national development.

The Navi Mumbai International Airport, developed under a Public-Private Partnership led by the Adani Group, was inaugurated today by Prime Minister Narendra Modi. The airport is set to become Asia’s largest air connectivity hub, enhancing regional connectivity, boosting economic growth, and expanding trade opportunities. Prime Minister Modi described the project as a “glimpse of Viksit Bharat,” highlighting its transformative impact on infrastructure and development in the region.

“The supply of 3,200 metric tonne of steel for this key project aligns with our focus on supporting critical infrastructure development through reliable and timely metal sourcing. Enlight Metals is committed to enhancing transparency and efficiency in the steel supply chain, contributing to projects integral to India’s growth objectives,” said Vedant Goel, Director, Enlight Metals.

Enlight Metals has implemented technology-driven solutions to strengthen supply chain efficiency, ensuring consistent availability of construction materials for large-scale projects nationwide. Its contribution to the Navi Mumbai International Airport underscores the company’s growing role in supporting India’s infrastructure development initiatives.

This milestone reflects Enlight Metals’ ongoing engagement in delivering quality materials and timely services for major national projects, further cementing its position as a reliable partner in India’s infrastructure sector