Concrete

Design for Solid Alternative Fuels

Published

2 years ago

January 12, 2024

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Kapil Kukreja, Group Manager; Dr D K Panda, Joint Director; and Bharat Bhushan, Project Engineer, National Council for Cement and Building Materials (NCB), Ballabgarh, India, present their findings in an article that delves into the methodology used to tackle the identified issue and discusses the R&D project taken up by NCB that resulted in the creation of an innovative design capable of effectively managing diverse alternative fuels and their combinations.

At COP26, India made a significant commitment by pledging to embrace a low-carbon growth path and to shift half of its energy consumption away from fossil fuels and towards non-fossil alternatives by the close of this decade. Moreover, India has set the ambitious goal of achieving carbon neutrality by the year 2070. To achieve the target of carbon neutrality, alternative fuels (AFs), including biomass, refuse-derived fuel (RDF), used tires, plastic waste and hazardous waste, which have the potential to replace conventional fossil fuels such as coal, pet coke, etc. These AF are seen as promising solutions in line with India’s mission to reach carbon neutrality.
Nonetheless, with the adoption of these AF, challenges were encountered in handling of AF and their mix, encompassing environmental, product quality, logistical issues, health and safety concerns, as well as the intricacies of the processes and operations involved. However, one of the main challenges faced while handling AF used in cement plants is the jamming of the transfer chute.
Chute transfers are vital for material handling but can often become weak links in the chain. These components are used in conveying systems to transfer bulk materials between feeders, screens, and from one conveyor to another or for discharge into burners/pre-calciner. Chute design requires careful attention, as handling AFs with variations in material characteristics or operational requirements can lead to productivity losses and operational disruptions due to jamming or unpredictable chute behaviour.

Problem with chutes
A survey was conducted in the Indian cement industry in the year of 2019-20 to assess the issues related with handling of AFs and their mix. Out of 100 questionnaires distributed, 61 responses were received, providing valuable insights. The survey highlighted that 78.7 per cent of respondents faced transfer chute issues when handling AFs, primarily jamming. The main reasons included using conventional chute designs unsuitable for heterogeneous AFs,
lack of knowledge about material flow and properties, and the unexpected introduction of new materials not considered during chute design. These issues led to significant maintenance efforts and operational disruptions.
One significant cause of chute jamming is the reliance on traditional chute design methods, which have been widely employed in the Indian cement industry for handling uniform materials like limestone, coal, bauxite, and iron ore. These methods fall short when dealing with heterogeneous AFs due to the varying properties of these materials throughout the year, depending on their source, mix content, and other factors. Additionally, a lack of understanding of material flow and physical properties, such as shape, size, angle of repose and angle of inclination, contributes to chute issues.
Another key factor identified in the survey is the unexpected introduction of new materials that were not considered during chute design. Anticipating all potential AF types during design is challenging because cement plants select materials based on factors like cost, suitability for their raw mix, fossil fuel prices, and availability. Therefore, it was challenge to design a transfer chute which can handle various AF and their mix without any jamming issues.

Solution
Based on the survey result, NCB took the problem related to jamming of transfer chute while utilising AFs and their mix in Indian Cement Industry as an R&D project. The project commenced with the site visit of cement plants, discussion with plant personnel and determination of material properties, providing essential foundational data. Utilising this data, key input parameters were carefully selected to run the Discrete Element Modelling (DEM) simulations.
To ensure the DEM model’s accuracy, it underwent calibration through the development of CAD calibration models. These models aligned the DEM model with real-world conditions. Following calibration, the existing transfer chute design was simulated using DEM. Accordingly, 14 simulations of AFs were conducted using the DEM, and the subsequent outcomes were thoroughly examined to pinpoint significant concerns associated with the traditional chute design. This analysis served as the basis for developing an improved transfer
chute model. The enhanced design was subsequently subjected to DEM simulation to assess its
performance. The various designs were evaluated and necessary modifications were made to address any identified issues to improve the performance of the transfer chute.

Fig 1: Simulation Results for Industrial Waste
Additionally, adjustments to the DEM parameters were carried out to fine-tune the model’s accuracy. The ultimate goal of this comprehensive process was to arrive at the final design of a transfer chute suitable for handling AF and their mix without jamming. The final parameters obtained after fine tuning and making adjustment to the chute design in simulation are as follows:
• Chute Valley Angle: 70°
• Chute Width (Minimum): 4.3 to 4.5 times the lump size
• Chute Hood Height at the material entrance: Minimum 0.6 times the Belt Width
• Cross-sectional area of transfer chute: Minimum 10 to 11 times of cross-sectional area of the material stream inside the chute.
• Selected Liners: UHMWPE
Based on the above parameters obtained after simulation, an experimental setup comprising four transfer chutes and belt conveyors was established on NCB’s Ballabgarh premises to conduct experimental study on the different samples of AF collected from different cement plants and sites. Thereafter, 19 AF and their mix were collected from different cement plants across India. The materials were experimented on different mass flow rates of 3, 5, 8, 10 and 15 tph and with moisture content levels spanning from 0.18 to 45 per cent. Remarkably, even after a total of 261 hours of operation on the experimental setup, no instances of jamming were observed in the transfer chute.
Even when faced with a jamming scenario, the innovative flexible arrangement introduced in the transfer chute design (patent filed by NCB) proven to be highly effective at swiftly addressing blockages caused by solid AF. It helps in clearing these blockages in just six minutes, representing a significant improvement compared to the conventional method, which typically necessitates a lengthy 85 to 105 minutes to remove and resume operations. This innovative approach optimises the chute cleaning process, ensuring uninterrupted operations.
Figures 2, 3 and 4 shows the general arrangement of the of the experimental setup and glimpses of experiments:

Conclusion
In the cement industry, conventional transfer chute designs have posed challenges when handling a range of diverse alternative fuels. To address this issue, a new transfer chute design capable of handling various AFs and their mixtures has been developed by the NCB. This innovative design can handle various AFs and their mixes and also significantly reduces chute jamming and cleaning time to 6-8 minutes. The NCB led the development of this versatile transfer chute design, which promises to enhance material handling in cement plants. The project’s outcomes led by NCB are valuable for system design improvements and process optimisation, streamlining cement plant operations.

ABOUT THE AUTHOR:
Dr Kapil Kukreja, Group Manager (CME), NCB has over 19 years of work experience in the field of System Design, Project Engineering and Management. He has previously worked with organisations like ACC, Holtec Consulting, JK White Cement etc.

Bharat Bhushan, Project Engineer (CME), NCB has a one-year experience as Project Engineer in the field of System Design, Project Engineering & Management.

Dr Dhirendra Kumar Panda, Joint Director, NCB has over 36 years of experience in the areas of Geology, Raw Materials and Mining and administrative experience as a Team Leader, Programme Leader and Head of the Centre.

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Dalmia Bharat Acquires Jaiprakash Associates Cement Assets for ₹2,850 Crore

Published

1 day ago

May 25, 2026

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Dalmia Cement executed a Business Transfer Agreement with Jaiprakash Associates and Adani Infra, to acquire 5.2 MnTPA of cement capacity across Madhya Pradesh and Uttar Pradesh.

Dalmia Cement (Bharat) announced on May 22, 2026 that it had signed a Business Transfer Agreement with Jaiprakash Associates Limited and Adani Infra (India) Limited for the acquisition of cement plants located at Rewa in Madhya Pradesh and Churk, Chunar and Sadwa in Uttar Pradesh. The deal was struck at an enterprise value of ₹2,850 crore and is expected to close within two weeks of execution.

The acquired assets from Jaiprakash Associates include 5.2 MnTPA of cement capacity and 3.3 MnTPA of clinker capacity. The package also covers 99 MW of thermal power capacity and railway sidings at Rewa, Chunar, and a common siding at Churk. This infrastructure gives the acquisition immediate operational utility beyond just production tonnage.

The transaction has a long backstory. Dalmia Cement had originally entered into a framework agreement with Jaiprakash Associates in December 2022, covering the sale of these business assets along with a long-term clinker supply arrangement. However, before the deal could be completed, Jaiprakash Associates was admitted to insolvency proceedings under the Insolvency and Bankruptcy Code. The earlier agreements could not be consummated as a result.

In an official statement, Puneet Dalmia, Managing Director & CEO, Dalmia Bharat, said, “I am very excited about addition of these assets in our portfolio. This serves as a great strategic fit for Dalmia. It helps us move forward in our journey to be a pan India player and provide a strong head start to serve the high potential markets in Central region. I am optimistic that the expansion potential of these assets along with close proximity with Dalmia’s captive mines will help us create a capacity hub for the future”.

Following the approval of Adani Group’s resolution plan for Jaiprakash Associates under the IBC framework, Dalmia approached the new management to revive discussions. The fresh Business Transfer Agreement was executed to settle all pending disputes, legal proceedings, and arbitration matters arising from the original framework agreement with Jaiprakash Associates.

Expanding market reach

Dalmia added, “Our familiarity with these assets under the earlier tolling arrangement gives us a deep understanding of the facilities and helps us establish strong connect with channel partners and vendors. We believe that this will help us in faster ramp up of capacities and quicker inroads into the market. As we look forward, I am very confident that we will be able to leverage the strengths of Dalmia to operate these assets in a manner where we can maximise value creation for all our stakeholders.”

With the addition of these plants, Dalmia Bharat’s total installed cement capacity will rise to 54.7 MnTPA upon consummation. The company has further expansion projects underway at Belgaum, Pune, and Kadapa, which are expected to take overall capacity to 66.7 MnTPA by Q2 to Q3 FY28.

The Central India location of the Jaiprakash Associates plants gives Dalmia Bharat faster access to markets in Madhya Pradesh and Uttar Pradesh than a greenfield build would have allowed. The company also cited debottlenecking and brownfield expansion as near-term opportunities at the acquired sites. Dalmia Bharat said the assets were expected to contribute positively to EBITDA and overall returns, given the pricing environment in the region and the company’s cost structure.

Concrete

30-Day Traffic Diversion In Place For CC Road Works In Madhapur

Diversions in place from May 16 for cement concrete road works

Published

4 days ago

May 22, 2026

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The Cyberabad Traffic Police issued a traffic advisory as road works begin for the laying of a cement concrete (CC) road from Jaya Shankar Statue to RRR Restaurant at Parvathnagar in Madhapur limits. The advisory indicated that traffic diversions will be in place for 30 days from May 16 to ensure the smooth flow of vehicles and to minimise congestion on the affected stretch. The measure aims to balance uninterrupted construction activity with the movement needs of commuters.

Traffic moving from Toddy Compound towards Parvathnagar village will be diverted at Parvathnagar junction towards Sunnam Cheruvu and the 100 feet road. Local motorists and public transport operators have been advised to follow the diversionary route as directed by traffic personnel on duty. Alternate routes and signage have been planned to mitigate delays and to manage peak hour congestion.

Police officials said the diversion had been planned to facilitate uninterrupted road works while maintaining traffic movement in the area. Commuters were urged to plan their travel accordingly and to cooperate with traffic staff managing the stretch. Authorities indicated that enforcement of diversions would be active and that violations could attract penalties.

The 30 day schedule is intended to allow contractors to complete the laying and curing phases with minimal interruption to vehicular flow. Residents and businesses in adjacent localities have been advised to factor the diversion into deliveries and travel plans. The traffic police promised continuous monitoring of the works and the operational diversions and emphasised that temporary inconvenience was necessary for longer term improvement of the road network. Traffic personnel will be stationed at key junctions and additional signage and temporary markings will be displayed to guide motorists and pedestrians through the revised alignments while public transport services will follow the diversion where feasible and operators have been asked to adjust timetables to minimise disruption.

Concrete

HeidelbergCement India Receives Consent For Khandwa Grinding Unit

Consent granted by Madhya Pradesh Pollution Control Board

Published

5 days ago

May 21, 2026

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HeidelbergCement India (HeidelbergCement India) has received regulatory consent to establish a cement blending and grinding unit at Village Dongaliya, Tehsil Punasa, District Khandwa in Madhya Pradesh. The consent was granted by the Madhya Pradesh Pollution Control Board under the Water (Prevention & Control of Pollution) Act, 1974 and the Air (Prevention & Control of Pollution) Act, 1981 and is dated 17 May 2026. The company disclosed the development in a filing made under Regulation 30 of the SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015.

The project plan envisages procurement of long term availability of fly ash and the allotment of land on lease for setting up the unit. The proposed facility is described as a blending and grinding installation which will process cementitious materials sourced from nearby operations and suppliers. Company filings state the measures required to secure raw material logistics and statutory compliance before commencing construction.

The addition of a grinding unit in Khandwa is intended to strengthen regional supply and improve logistical efficiency by reducing haulage distances for finished product. The unit is expected to complement existing capacities in central India and to offer flexibility in product mix through blending operations. The reliance on fly ash as a supplementary cementitious material will necessitate long term supply agreements with thermal power producers and coordination with waste utilisation policies.

The disclosure to the regulator and to the stock exchanges follows standard corporate governance practice and aims to keep investors apprised of capital expenditure initiatives. The company indicated that subsequent permits and clearances would be sought in accordance with applicable environmental and land use rules. The project is presented as part of HeidelbergCement India’s broader strategy to optimise capacity distribution and to respond to regional demand dynamics.