Sumit Banerjee, Vice-Chairman, Reliance Cement.
All our cement plants, either in project phase or in project development phase, will be highly energy- efficient. These plants will be designed to use alternative fuel and raw materials (AFR) and be equipped with waste heat recovery system for power generation. A sustainability roadmap with medium and long- term action plans to adopt various carbon emission reduction levers has been developed, says Sumit Banerjee, Vice-Chairman, Reliance Cement. Excerpts from the interview.
How do you look at the sustainability issues in the cement industry?
Technological improvement is a key pillar in the cement industry’s drive to reduce emissions levels and energy consumption. Research and development investments have enabled cement producers worldwide to install modern, energy-efficient technology in new, and to some extent, in existing, cement plants. New technologies have enabled increased use of clinker substitutes and alternative fuels in cement production, leading to significant direct (e.g. from limestone decarbonisation and fuel burning) CO2 emissions reductions. Technology developments have also enabled significant indirect emissions reductions (e.g. from electricity use). CO2 emissions on account of cement are expected to go up to 488 mt from about 145 mt in 2010 if no action is taken on carbon emission levers. The industry need to focus on five broad categories of carbon emission reduction levers: thermal and electrical energy efficiency, co-processing of alternate fuels and raw materials, clinker substitution, waste heat recovery for power generation and adoption of new technologies like CCS (Carbon Capture and Storage) algal growth promotion and use of bio-fuels.
Highlight the strategies to conserve the fossil fuel through the use AFR?
As against the global average of alternative fuel usage of 4.3 per cent, the Indian cement industry is just at 0.6 per cent. There is a huge potential to increase the AFR usage in India. Finding ways to reduce both energy needs and reliance on fossil fuels is a top priority for Reliance Cement. Although coal, petroleum coke, and other fossil fuels have been traditionally burned in cement kilns, we are closely working with equipment manufacturers, government agencies and technology supplier to increase use of AFR in our cement plants.
Brief us on the thrust given to renewable energy sources.
With the ever-growing thrust on conservation of fossil fuel resources, Reliance Cement emphasises the need for integrating the alternate and renewable energy into the system. We are working on installation of waste heat recovery systems in all our plants. We are also exploring other sources such as wind power, biomass based power generation, hydropower generation to name a few.
What are the steps taken to reduce carbon footprint through WHR systems?
The WHR system is a proven technology that supplies a significant part of a plant’s power needs at no extra fuel cost, reduces its carbon footprint and saves precious water. Most of the WHR solutions supplied in industry today employ Rankine steam cycle systems. In cement and minerals processes, vent hot gas is used to generate steam in a boiler. A 10 mw WHR power plant can give reduction of 50 KT CO2 emissions annually. The payback period for a waste heat recovery project is attractive. In fact, savings in production costs and emissions can lead to a return on investment within a few years, depending on the cost of electricity and scale of the plant.
What are the steps initiated to reduce water consumption in your plants?
Considering the fact that over-consumption of water leads to the over-consumption of other non-renewable resources, Reliance Cement is in advance stage for setting up state-of- the-art cement plants, wherein we have selected the following eco friendly equipment: Roller press in place of vertical mill for raw material grinding, in order to reduce the water as well as power consumption.
- Reduction in water consumption by installing waste heat recovery unit, treated water from STP and waste water recycling – RO plant.
- Collection of rooftop rain water in reservoir.
- Air cooled condensers.
- Rain water harvesting and storm water catchments’ ponds connected to all drains and recycle of catchments’ water after filtration.
Tell us about high efficiency pollution control equipment used?
Electrostatic precipitators (ESP) and bag houses are primarily used in cement plant to reduce particulate emissions. ESPs are used to clean the clinker cooler and captive power plant exhaust gases, whereas bag houses are used mainly to filter raw mill-kiln exhaust gases, cement mill, coal mill, packing plant and other process gas venting. There are other systems used in cement plant to reduce SOx and NOx emissions. Selective non-catalytic reduction is used to prevent NOx formation in the cement kiln. Granulated activated carbon systems, bio filtration, acid scrubbers, hot waste ceramic filters are used to reduce volatile organic compounds (VOC) and sulfurous emissions in cement plant.
- How green is Reliance Cement’s operation, from mining to production and despatch?
- Various steps have been taken in terms of technology and equipment selection, engineering, logistics optimisation so that Reliance Cement can achieve benchmark in energy efficiency while the plants will be in operation. Some of them are described below: Electric excavators in mining operation and transport of limestone from mines by 7 km long over land belt conveyor.
- Covered storage for all materials and fuels.
- High pressure roller press grinding mill for raw material.
- Fuel efficient pyro-processing with 6-stage preheater, inline calciner, most efficient clinker cooler, most efficient fuel burner.
- Technology compatible to use AFR in future.
- WHRS power generation unit. Vertical roller mills for cement grinding. End to end laboratory automation covering automated sampling, sample preparation for testing, inline analysis of all quality parameters through most sophistication quality testing analysers and software driven quality control not only to achieve best quality of cement but also to achieve highest possible clinker substitute.
- Intelligent MCCs and gas insulated substations.Performance guarantees for stack emissions has been kept lower than European Union norms, additionally performance guarantees for fugitive emission has been asked from vendors with stringent norms.
What are the advantages of PAT Scheme?
The PAT scheme is a unique and innovative programme with no precedence anywhere else in the world. The key goal of the scheme is to mandate specific energy efficiency for the most energy efficiency for the most energy intensive industries, and further incentivise them to achieve better energy efficiency improvements that are superior to their specified specific energy consumption improvement targets. To facilitate this, the scheme provides the option to industries which achieve superior savings to receive energy savings certificates for these excess savings, and to trade the additional energy savings certificates with other energy-intensive industries (the Designated Consumers, who can utilise these certificates to comply with their own reduction targets. The Energy Savings Certificates (ESCerts) so issued will be tradable on special trading platforms to be created in the two power exchanges (Indian Energy Exchange and Power Exchange India). The cement plant is an energy intensive unit, where the energy cost accounts for about 30 per cent of the total manufacturing cost. Energy savings of 0.816 million tonnes of oil equivalent (Mtoe) (34PJ) per year are expected to be achieved, which is around 12 per cent of total national energy savings targets assessed under PAT.
Will Reliance Cement be opting for a Greenco Rating?
Yes, Reliance Cement would opt for the Greenco rating after stabilisation of its Maihar plant.
How do you assess the challenges on the logistics front?
Logistics is a major challenge for the cement industry. Cement is a high volume, low value commodity. The logistics cost today is almost 1/3rd of the total cost and this will further increase in future years. We, at Reliance Cement, are exploring various modes of logistics that can provide a cost-effective means of cement transportation. This includes using more railway routes than roads, shrinking lead distance (distance between the manufacturing facility and market) and use of inland waterways. Reliance is setting up blending units near to the Reliance power plants where very fine fly ash will be blended with OPC to produce PPC and coarser fly ash will be transported to integrated units and grinding units to produce PPC. In this way, grinding energy to grind fine fly ash is eliminated. Split units will reduce emissions due to better logistic options.
Where does the company see itself five years down the line? The opportunity for improvement does exist, particularly in the area of five key levers that can contribute to emissions reductions: alternative fuel and raw materials; energy efficiency; clinker substitution; waste heat recovery and newer technologies. This roadmap sets out a pathway by which the Indian cement industry can reach its targets to improve energy efficiency and reduce CO2 emissions by 2050, thereby laying the foundation for low-carbon growth in the years beyond.