Concrete
Environmental Benefits of Using Waste Glass as Pozzolana
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2 years agoon
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admin
Dr SB Hedge, Professor, Jain University and Visiting Professor, Pennsylvania State University, United States of America, discusses the environmental benefits of using waste glass as Pozzolana in this concluding part of the article.
Pozzolanic properties of waste glass refer to its ability to react with calcium hydroxide in the presence of water to form cementitious compounds. This reaction, known as the pozzolanic reaction, contributes to the strength and durability of cementitious materials.
Findings based on the investigation on the Pozzolanic properties
Here are some details on the pozzolanic properties of waste glass and examples of its usage:
Amorphous Silica Content: Waste glass typically contains a significant amount of amorphous silica, which is a key factor in its pozzolanic activity. Amorphous silica has a high
surface area, allowing it to react readily
with calcium hydroxide and form additional cementitious compounds.
Reactivity and Fineness: The reactivity of waste glass depends on factors such as its chemical composition, particle size distribution, and surface area. To enhance its pozzolanic reactivity, waste glass is often ground to a fine powder. Increased fineness improves the contact between waste glass particles and calcium hydroxide, facilitating the pozzolanic reaction.
Pozzolanic Reaction Products: When waste glass reacts with calcium hydroxide in the presence of water, it forms additional cementitious compounds, such as calcium silicate hydrate (C-S-H) gel. The C-S-H gel contributes to the strength and binding properties of the
cementitious matrix.

Examples of Usage
Partial cement replacement: Waste glass can be used as a partial replacement for cement in concrete production. Typically, a portion of the cement is substituted with finely ground waste glass powder. This reduces the overall cement content while maintaining or improving the mechanical properties and durability of the concrete.
Glass powder addition in concrete mixes: Waste glass powder can be directly added to concrete mixes as an additional pozzolanic material. It acts as a supplementary cementitious material (SCM) alongside other pozzolanic materials like fly ash or silica fume. This combination enhances the reactivity and overall performance of the concrete.
Glass aggregate in concrete: In addition to using waste glass as a pozzolanic material, it can also be used as a fine or coarse aggregate in concrete production. By incorporating waste glass aggregates, both the pozzolanic and aggregate properties of the glass are utilised. This approach enhances the sustainability of concrete while maintaining structural integrity.
Glass fibre reinforcement: Waste glass fibres can be used as reinforcement in cementitious composites. The glass fibres provide tensile strength and improve the overall performance of the concrete. This application is particularly useful in construction elements requiring enhanced durability and crack resistance.
Glass as pozzolanic additive in mortars: Waste glass can be used as a pozzolanic additive in mortar mixes. Mortars containing waste glass exhibit improved workability, increased strength and reduced permeability. This makes them suitable for applications such as plastering, masonry and tile adhesives.
Waste glass possesses pozzolanic properties due to its high amorphous silica content. By utilising waste glass as a pozzolanic material, its environmental impact can be reduced while enhancing the performance and sustainability of cementitious materials.
The examples provided demonstrate the versatile usage of waste glass in cement and concrete applications, contributing to a more sustainable construction industry.

Environmental Benefits
The utilisation of waste glass as a pozzolanic material in cement production offers significant environmental benefits. Here is a detailed account of these benefits:
Waste reduction and recycling: Waste glass, if not properly managed, poses a significant environmental challenge. By using waste glass as a pozzolanic material, it is diverted from landfills or incineration, reducing the need for new disposal sites and minimising the environmental impact associated with glass waste. Recycling waste glass as a pozzolana promotes a circular economy by converting it into a valuable resource.
Conservation of natural resources: The incorporation of waste glass in cement production reduces the need for virgin raw materials, such as limestone or silica. By substituting a portion of cement with waste glass, natural resources are conserved, including the energy and water required for extraction and processing of raw materials. This conservation helps in preserving natural ecosystems and reducing the overall ecological footprint.
Energy savings and emissions reduction: The production of cement is energy-intensive and contributes to greenhouse gas emissions, primarily carbon dioxide (CO2). By using waste glass as a pozzolanic material, the cement content in concrete is reduced, resulting in lower energy consumption and CO2 emissions during cement manufacturing. This reduction in energy usage and emissions contributes to mitigating climate change and achieving sustainability goals.
Reduced landfill space and leachate generation: When waste glass is disposed of in landfills, it occupies valuable space and can contribute to environmental concerns. Glass waste in landfills may also produce leachate, potentially contaminating soil and groundwater. Utilising waste glass as a pozzolanic material reduces
the amount of glass waste sent to landfills, alleviating the pressure on waste management infrastructure and minimising the associated environmental risks.
Improved air quality: Cement production is associated with the release of pollutants, including dust, particulate matter, and potentially harmful gases. By replacing a portion of cement with waste glass, the production of cementitious materials can be optimised. The use of waste glass as a pozzolana reduces the overall emissions of particulate matter and improves air quality in and around cement plants, promoting a healthier environment for nearby communities.
Enhanced durability and reduced maintenance: Concrete incorporating waste glass as a pozzolanic material exhibits improved durability and reduced permeability. This translates into longer service life for concrete structures, reduced maintenance requirements, and decreased need for repairs or replacements. By extending the life of concrete, the environmental impact associated with new construction projects is minimised.
Waste Glass Addition
The addition of waste glass to concrete can significantly improve its performance in several ways. Here are the key ways in which waste glass enhances the performance of concrete:
- Increased strength and durability: The incorporation of waste glass as a pozzolanic material in concrete leads to the formation of additional cementitious compounds. These compounds, such as calcium silicate hydrate (C-S-H) gel, contribute to the strength and durability of the concrete. The pozzolanic reaction between waste glass and calcium hydroxide results in denser and more compact concrete, improving its compressive and flexural strength.
- Reduced permeability: Concrete containing waste glass exhibits reduced permeability to water and other potentially harmful substances. The pozzolanic reaction of waste glass results in the formation of a refined pore structure within the concrete matrix. This refined pore structure restricts the movement of water and other aggressive agents, enhancing the concrete’s resistance to moisture ingress, chemical attack, and freeze-thaw damage.
- Enhanced chemical resistance: The pozzolanic reaction of waste glass in concrete leads to the formation of calcium silicate hydrate (C-S-H) gel, which provides improved chemical resistance. This resistance makes the concrete less susceptible to chemical degradation caused by substances such as sulphates, chlorides and acids.
Concrete with waste glass as a pozzolanic material exhibits better long-term performance in aggressive environments. - Improved workability and cohesion: The addition of waste glass as a pozzolanic material can enhance the workability and cohesion of concrete. Due to the fine particle size and pozzolanic nature of waste glass, it acts as a filler material, improving the packing and lubrication of the concrete mixture. This improved workability allows for easier placement, consolidation, and finishing of
the concrete. - Mitigation of alkali-silica reaction: Alkali-Silica Reaction (ASR) is a chemical reaction that can occur between certain reactive silica minerals in aggregates and the alkalis present in cement. This reaction can lead to expansive cracking and deterioration of concrete. Waste glass, being an inert material, can act as a mitigating agent for ASR by replacing some of the reactive silica in the concrete mix.
- Sustainability and eco-friendliness: In addition to performance improvements, the utilisation of waste glass in concrete contributes to sustainability and eco-friendliness. By incorporating waste glass as a pozzolanic material, the consumption of cement is reduced, resulting in CO2 emissions associated with cement production. This reduction in CO2 emissions aligns with environmental goals and contributes to a more sustainable construction industry.
Challenges and Considerations
The utilisation of waste glass as a pozzolanic material in cement production does pose some challenges. Proper processing and grinding of waste glass to achieve optimal fineness is crucial to ensure its reactivity. The potential presence of impurities in the waste glass, such as metals or contaminants, requires careful selection and pre-treatment. Additionally, the impact of incorporating waste glass on the fresh and hardened properties of concrete should be evaluated to ensure compatibility with specific project requirements.
Research and Industry Initiatives
Ongoing research and industry initiatives are focused on optimising the use of waste glass as a pozzolanic material. Studies explore various methods of processing and grinding waste glass to enhance its reactivity and maximise its utilisation. Additionally, there is a scope to investigate the influence of waste glass characteristics, such as particle size, composition and treatment, on the properties of concrete. These efforts aim to develop guidelines and standards for incorporating waste glass in cement production.
Conclusion
The use of waste glass as a pozzolanic material in cement production offers a sustainable solution to address environmental concerns associated with both waste glass disposal and cement manufacturing. By harnessing the pozzolanic properties of waste glass, cement producers can reduce their carbon footprint, enhance concrete performance, and contribute to a more circular economy.
The addition of waste glass as a pozzolanic material significantly enhances the performance of concrete. The improvements include increased strength and durability, reduced permeability, enhanced chemical resistance, improved workability and cohesion, mitigation of alkali-silica reaction and sustainability benefits. By embracing waste glass in concrete production, the construction industry can create more resilient and eco-friendly structures while effectively utilising a valuable waste material.
Further research, collaboration and implementation efforts are essential to fully exploit the potential of waste glass as a valuable resource.
References
- Utilisation of Waste Glass Powder in Concrete by P. Manoj Kumar, K. Sreenivasulu, and M. Srinivasulu Reddy, International Journal of Innovative Research in Science, Engineering and Technology, 2013.
- Recycling of Waste Glass as a Partial Replacement for Fine Aggregate in Concrete Mix by W. A. Rahman, M. A. S. Al-gahtani, and M. A. K. El-Kourd, Journal of King Saud University – Engineering Sciences, 2010.
- Mechanical and Durability Properties of Concrete Containing Glass Powder as Partial Replacement of Cement by A. Shayan and R. Xu, Construction and Building Materials, 2004.
- Properties of Glass Concrete Containing Fine and Coarse Glass Aggregates by Z. Feng, S. Xie, and Y. Zhou, Journal of Materials in Civil Engineering, 2011.
You can find part one in the August issue of Indian Cement Review.
ABOUT THE AUTHOR
Dr SB Hegde is a Professor at Jain University and a Visiting Professor at the Pennsylvania State University, United States of America.
Concrete
Our strategy is to establish reliable local partnerships
Published
4 hours agoon
February 19, 2026By
admin
Jean-Jacques Bois, President, Nanolike, discusses how real-time data is reshaping cement delivery planning and fleet performance.
As cement producers look to extract efficiency gains beyond the plant gate, real-time visibility and data-driven logistics are becoming critical levers of competitiveness. In this interview with Jean-Jacques Bois, President, Nanolike, we discover how the company is helping cement brands optimise delivery planning by digitally connecting RMC silos, improving fleet utilisation and reducing overall logistics costs.
How does SiloConnect enable cement plants to optimise delivery planning and logistics in real time?
In simple terms, SiloConnect is a solution developed to help cement suppliers optimise their logistics by connecting RMC silos in real time, ensuring that the right cement is delivered at the right time and to the right location. The core objective is to provide real-time visibility of silo levels at RMC plants, allowing cement producers to better plan deliveries.
SiloConnect connects all the silos of RMC plants in real time and transmits this data remotely to the logistics teams of cement suppliers. With this information, they can decide when to dispatch trucks, how to prioritise customers, and how to optimise fleet utilisation. The biggest savings we see today are in logistics efficiency. Our customers are able to sell and ship more cement using the same fleet. This is achieved by increasing truck rotation, optimising delivery routes, and ultimately delivering the same volumes at a lower overall logistics cost.
Additionally, SiloConnect is designed as an open platform. It offers multiple connectors that allow data to be transmitted directly to third-party ERP systems. For example, it can integrate seamlessly with SAP or other major ERP platforms, enabling automatic order creation whenever replenishment is required.
How does your non-exclusive sensor design perform in the dusty, high-temperature, and harsh operating conditions typical of cement plants?
Harsh operating conditions such as high temperatures, heavy dust, extreme cold in some regions, and even heavy rainfall are all factored into the product design. These environmental challenges are considered from the very beginning of the development process.
Today, we have thousands of sensors operating reliably across a wide range of geographies, from northern Canada to Latin America, as well as in regions with heavy rainfall and extremely high temperatures, such as southern Europe. This extensive field experience demonstrates that, by design, the SiloConnect solution is highly robust and well-suited for demanding cement plant environments.
Have you initiated any pilot projects in India, and what outcomes do you expect from them?
We are at the very early stages of introducing SiloConnect in India. Recently, we installed our
first sensor at an RMC plant in collaboration with FDC Concrete, marking our initial entry into the Indian market.
In parallel, we are in discussions with a leading cement producer in India to potentially launch a pilot project within the next three months. The goal of these pilots is to demonstrate real-time visibility, logistics optimisation and measurable efficiency gains, paving the way for broader adoption across the industry.
What are your long-term plans and strategic approach for working with Indian cement manufacturers?
For India, our strategy is to establish strong and reliable local partnerships, which will allow us to scale the technology effectively. We believe that on-site service, local presence, and customer support are critical to delivering long-term value to cement producers.
Ideally, our plan is to establish an Indian entity within the next 24 months. This will enable us to serve customers more closely, provide faster support and contribute meaningfully to the digital transformation of logistics and supply chain management in the Indian cement industry.
Pankaj Kejriwal, Whole Time Director and COO, Star Cement, on driving efficiency today and designing sustainability for tomorrow.
In an era where the cement industry is under growing pressure to decarbonise while scaling capacity, Star Cement is charting a pragmatic yet forward-looking path. In this conversation, Pankaj Kejriwal, Whole Time Director and COO, Star Cement, shares how the company is leveraging waste heat recovery, alternative fuels, low-carbon products and clean energy innovations to balance operational efficiency with long-term sustainability.
How has your Lumshnong plant implemented the 24.8 MW Waste Heat Recovery System (WHRS), and what impact has it had on thermal substitution and energy costs?
Earlier, the cost of coal in the Northeast was quite reasonable, but over the past few years, global price increases have also impacted the region. We implemented the WHRS project about five years ago, and it has resulted in significant savings by reducing our overall power costs.
That is why we first installed WHRS in our older kilns, and now it has also been incorporated into our new projects. Going forward, WHRS will be essential for any cement plant. We are also working on utilising the waste gases exiting the WHRS, which are still at around 100 degrees Celsius. To harness this residual heat, we are exploring systems based on the Organic Rankine Cycle, which will allow us to extract additional power from the same process.
With the launch of Star Smart Building Solutions and AAC blocks, how are you positioning yourself in the low-carbon construction materials segment?
We are actively working on low-carbon cement products and are currently evaluating LC3 cement. The introduction of autoclaved aerated concrete (AAC) blocks provided us with an effective entry into the consumer-facing segment of the industry. Since we already share a strong dealer network across products, this segment fits well into our overall strategy.
This move is clearly supporting our transition towards products with lower carbon intensity and aligns with our broader sustainability roadmap.
With a diverse product portfolio, what are the key USPs that enable you to support India’s ongoing infrastructure projects across sectors?
Cement requirements vary depending on application. There is OPC, PPC and PSC cement, and each serves different infrastructure needs. We manufacture blended cements as well, which allows us to supply products according to specific project requirements.
For instance, hydroelectric projects, including those with NHPC, have their own technical norms, which we are able to meet. From individual home builders to road infrastructure, dam projects, and regions with heavy monsoon exposure, where weather-shield cement is required, we are equipped to serve all segments. Our ability to tailor cement solutions across diverse climatic and infrastructure conditions is a key strength.
How are you managing biomass usage, circularity, and waste reduction across
your operations?
The Northeast has been fortunate in terms of biomass availability, particularly bamboo. Earlier, much of this bamboo was supplied to paper plants, but many of those facilities have since shut down. As a result, large quantities of bamboo biomass are now available, which we utilise in our thermal power plants, achieving a Thermal Substitution Rate (TSR) of nearly 60 per cent.
We have also started using bamboo as a fuel in our cement kilns, where the TSR is currently around 10 per cent to 12 per cent and is expected to increase further. From a circularity perspective, we extensively use fly ash, which allows us to reuse a major industrial waste product. Additionally, waste generated from HDPE bags is now being processed through our alternative fuel and raw material (AFR) systems. These initiatives collectively support our circular economy objectives.
As Star Cement expands, what are the key logistical and raw material challenges you face in scaling operations?
Fly ash availability in the Northeast is a constraint, as there are no major thermal power plants in the region. We currently source fly ash from Bihar and West Bengal, which adds significant logistics costs. However, supportive railway policies have helped us manage this challenge effectively.
Beyond the Northeast, we are also expanding into other regions, including the western region, to cater to northern markets. We have secured limestone mines through auctions and are now in the process of identifying and securing other critical raw material resources to support this expansion.
With increasing carbon regulations alongside capacity expansion, how do you balance compliance while sustaining growth?
Compliance and growth go hand in hand for us. On the product side, we are working on LC3 cement and other low-carbon formulations. Within our existing product portfolio, we are optimising operations by increasing the use of green fuels and improving energy efficiency to reduce our carbon footprint.
We are also optimising thermal energy consumption and reducing electrical power usage. Notably, we are the first cement company in the Northeast to deploy EV tippers at scale for limestone transportation from mines to plants. Additionally, we have installed belt conveyors for limestone transfer, which further reduces emissions. All these initiatives together help us achieve regulatory compliance while supporting expansion.
Looking ahead to 2030 and 2050, what are the key innovation and sustainability priorities for Star Cement?
Across the cement industry, carbon capture is emerging as a major focus area, and we are also planning to work actively in this space. In parallel, we see strong potential in green hydrogen and are investing in solar power plants to support this transition.
With the rapid adoption of solar energy, power costs have reduced dramatically – from 10–12 per unit to around2.5 per unit. This reduction will enable the production of green hydrogen at scale. Once available, green hydrogen can be used for electricity generation, to power EV fleets, and even as a fuel in cement kilns.
Burning green hydrogen produces only water and oxygen, eliminating carbon emissions from that part of the process. While process-related CO2 emissions from limestone calcination remain a challenge, carbon capture technologies will help address this. Ultimately, while becoming a carbon-negative industry is challenging, it is a goal we must continue to work towards.
Concrete
Turning Downtime into Actionable Intelligence
Published
5 hours agoon
February 19, 2026By
admin
Stoppage Insights instantly identifies root causes and maps their full operational impact.
In cement, mining and minerals processing operations, every unplanned stoppage equals lost production and reduced profitability. Yet identifying what caused a stoppage remains frustratingly complex. A single motor failure can trigger cascading interlocks and alarm floods, burying the root cause under layers of secondary events. Operators and maintenance teams waste valuable time tracing event chains when they should be solving problems. Until now.
Our latest innovation to our ECS Process Control Solution(1) eliminates this complexity. Stoppage Insights, available with the combined updates to our ECS/ControlCenter™ (ECS) software and ACESYS programming library, transforms stoppage events into clear, actionable intelligence. The system automatically identifies the root cause of every stoppage – whether triggered by alarms, interlocks, or operator actions – and maps all affected equipment. Operators can click any stopped motor’s faceplate to view what caused the shutdown instantly. The Stoppage UI provides a complete record of all stoppages with drill-down capabilities, replacing manual investigation with immediate answers.
Understanding root cause in Stoppage Insights
In Stoppage Insights, ‘root cause’ refers to the first alarm, interlock, or operator action detected by the control system. While this may not reveal the underlying mechanical, electrical or process failure that a maintenance team may later discover, it provides an actionable starting point for rapid troubleshooting and response. And this is where Stoppage Insights steps ahead of traditional first-out alarm systems (ISA 18.2). In this older type of system, the first alarm is identified in a group. This is useful, but limited, as it doesn’t show the complete cascade of events, distinguish between operator-initiated and alarm-triggered stoppages, or map downstream impacts. In contrast, Stoppage Insights provides complete transparency:
- Comprehensive capture: Records both regular operator stops and alarm-triggered shutdowns.
- Complete impact visibility: Maps all affected equipment automatically.
- Contextual clarity: Eliminates manual tracing through alarm floods, saving critical response time.
David Campain, Global Product Manager for Process Control Systems, says, “Stoppage Insights takes fault analysis to the next level. Operators and maintenance engineers no longer need to trace complex event chains. They see the root cause clearly and can respond quickly.”
Driving results
1.Driving results for operations teams
Stoppage Insights maximises clarity to minimise downtime, enabling operators to:
• Rapidly identify root causes to shorten recovery time.
• View initiating events and all affected units in one intuitive interface.
• Access complete records of both planned and unplanned stoppages
- Driving results for maintenance and reliability teams
Stoppage Insights helps prioritise work based on evidence, not guesswork:
• Access structured stoppage data for reliability programmes.
• Replace manual logging with automated, exportable records for CMMS, ERP or MES.(2)
• Identify recurring issues and target preventive maintenance effectively.
A future-proof and cybersecure foundation
Our Stoppage Insights feature is built on the latest (version 9) update to our ACESYS advanced programming library. This industry-leading solution lies at the heart of the ECS process control system. Its structured approach enables fast engineering and consistent control logic across hardware platforms from Siemens, Schneider, Rockwell, and others.
In addition to powering Stoppage Insights, ACESYS v9 positions the ECS system for open, interoperable architectures and future-proof automation. The same structured data used by Stoppage Insights supports AI-driven process control, providing the foundation for machine learning models and advanced analytics.
The latest releases also respond to the growing risk of cyberattacks on industrial operational technology (OT) infrastructure, delivering robust cybersecurity. The latest ECS software update (version 9.2) is certified to IEC 62443-4-1 international cybersecurity standards, protecting your process operations and reducing system vulnerability.
What’s available now and what’s coming next?
The ECS/ControlCenter 9.2 and ACESYS 9 updates, featuring Stoppage Insights, are available now for:
- Greenfield projects.
- ECS system upgrades.
- Brownfield replacement of competitor systems.
Stoppage Insights will also soon integrate with our ECS/UptimeGo downtime analysis software. Stoppage records, including root cause identification and affected equipment, will flow seamlessly into UptimeGo for advanced analytics, trending and long-term reliability reporting. This integration creates a complete ecosystem for managing and improving plant uptime.
(1) The ECS Process Control Solution for cement, mining and minerals processing combines proven control strategies with modern automation architecture to optimise plant performance, reduce downtime and support operational excellence.
(2) CMMS refers to computerised maintenance management systems; ERP, to enterprise resource planning; and MES to manufacturing execution systems.
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