The cement industry will have to gear up to meet fresh challenges in the future, such as upgrading its technologies for carbon capture and storage, says SAILESH MOHTA, PRESIDENT - MARKETING, WONDER CEMENT.
India is the second-largest cement producer in the world and accounts for 6.7 per cent of the world’s cement output. If you look at the statistics, cement production capacity is estimated to touch 550 million tonnes (MT) by FY20. Of the total capacity, 98 per cent lies with the private sector and the rest with the public sector.
While construction activities will keep driving demand, the Indian cement industry will need to control costs and continuously upgrade technology to stay globally competitive. The Indian cement industry has realised that strong business growth can be achieved by sustaining manufacturing in an ecofriendly manner.
There is a vital need for the cement industry to bring in new technologies and processes to achieve higher energy efficiency and to drive sustainability. In a due process of moving ahead to embrace green technologies, we should be aware of the pros and cons of greenhouse technology.
Cement Industry Analysis
Many years of industry experience have shown that the use of wastes as alternative fuels by cement plants is both ecologically and economically justified. Alternative fuel utilisation in the cement industry started in the 1980s. Starting in calciner lines, up to almost 100 per cent alternative fuel firing at the pre-calciner stage was very quickly achieved.
Energy costs and environmental concerns have encouraged cement companies worldwide to evaluate to what extent conventional fuels can be replaced by waste materials, such as waste oils, mixtures of non-recycled plastics and paper, used tires, biomass wastes, and even wastewater sludge. The clinker firing process is well-suited for various alternative fuels; the goal is to optimise process controls and alternative fuel consumption, while maintaining clinker product quality. The potential is enormous, since the global cement industry produces about 3.5 billion tonnes that consume nearly 350 million tonnes of coal-equivalent fossil and alternative fuels. This study has shown that several cement plants have replaced part of the fossil fuel used by alternative fuels, such as waste-recovered fuels.
The traditional fuels used in traditional kilns include coal, oil, petroleum coke, and natural gas. The substitution of fossil fuels by alternative fuels in the production of cement clinker is of great importance both for cement producers and for society, because it conserves fossil fuel reserves and, in the case of biogenic wastes, reduces greenhouse gas emissions. In addition, the use of alternative fuels can help to reduce the costs of cement production.
Cement entrepreneurs have to face many challenges while setting up new cement manufacturing plants on greenfield sites. Emphasis on sustainable development is a new dimension to consider while designing the plant. The cement industry is committed to reducing the emission of Greenhouse Gasses (GHG) and to save limestone reserves and fossil fuels, while simultaneously maintaining the quality of the ambient air. All new cement plants are adopting green processes. This means they would be making blended/composite cement, using alternate fuels, using waste gases to co-generate power or to even make cement using renewable sources of power like wind and solar.
Though not mandatory now, the industry is expected to monitor emissions of greenhouse gases. These stipulations are to be met by all proposed cement plants, green or gray. Since the cement industry is committed to the principle of sustainable development, it will willingly comply with these stipulations and do necessary planning in advance.
Norms have been developed for green buildings that make maximum use of sun and wind to reduce dependence on lighting and air- conditioning. Though not mandatory, adopting them would make the existing plants greener. The Bureau of Energy Efficiency has issued norms for lighting fixtures and cooling media to be used in refrigerators and air- conditioners. It would be best to keep these in mind right from the planning stage.
meeting these challenges
There are several real and tangible benefits of accepting the challenges and in greening the cement plants. GHG emissions can be reduced from ~0.76 t/t for OPC to 0.30 t/t for slag cement with Alternate Fuels (AF) and Waste Heat Recovery Systems (WHR). Substantial savings can be achieved by conserving reserves of limestone and fossil fuels. Capital costs of annual capacity can come down by 30 to 40 per cent even after allowing for additional costs for AF and WHR. Costs of production of naked cement excluding works also come down by 20 to 25 per cent in case of blended cements with AF and WHR.
Power plants based on renewable sources such as wind and solar power will soon become an integral part of a new cement plant, making them greener as these sources of energy are totally free of GHG emissions. The necessary technology to meet these goals is now available and very reliable.
However, the main problem associated with these sources is that the generation of wind and solar power is not consistent. The capacity factor is also very low compared to that of thermal power plants. Secondly, it may not always be possible to locate wind or solar power plants close to a cement plant. The plant would have to manage several sources of electrical energy, grid, captive power plant, WHRS and power from renewable energy. A sound strategy must be in place to ensure continuity of power at optimum cost.
The cement industry will have to gear up to meet new challenges in the future, such as upgrading its technologies for carbon capture and storage. GHG emissions cannot be pulled down to the targeted levels merely by making blended cement and by using AF. There are technologies for separating CO2 from waste gases on the horizon. It could be used by other industries or it can also be used for making new cement substitutes such as those made by Calera Corporation.
Several cement substitutes like Calera, Novacem and Aether, are in various stages of development. All the new cement is green. The cement industry should be watchful and examine how these green products can be made in their existing production facilities.
Worldwide, the cement industry is facing growing challenges in conserving material and energy resources, as well as reducing CO2 emissions. Cement producers are striving to increase energy efficiency and the use of alternative raw materials and fuels. Therefore, the use of alternative fuels has already increased significantly, but the potential for further increases still exists. In a modern cement plant, 60 per cent of the CO2 emitted by a cement plant results from the calculations of limestone, 30 per cent from combustion of fuels in the kiln and 10 per cent from other downstream plant operations.
The main part of fuel consumption and consequently CO2 generation takes place in the calciner and clinker forming kiln. The utilisation of low-carbon content fuel with high hydrogen-to-carbon (H/C) ratio instead of conventional fossil fuels can remarkably diminish the rate of CO2 emissions in the process. In addition to producing a smaller quantity of CO2, the use of alternative fuels has been shown to improve refractory life and also reduce pressure drop in preheater tower.
The use of alternative fuels in cement plants also reduces emissions from landfills. Therefore, it has been estimated that the utilisation of this type of fuel will increase at the rate of 1 per cent per year worldwide.
Energy-efficiency improvements (use of energy-efficient equipment, process modifications, etc.), fuel switching to waste as alternative fuel and cement blending using industrial byproducts have helped decrease CO2 emissions associated with energy conversion.
About the author
Being one of the youngest Chartered Accountants in the country during his time, Sailesh Mohta had to wait for only six months to get his CA Membership. That did not stop him from scaling the heights he has reached today. With over 30 years of experience in the cement industry, his experience is not only immensely valuable, but also insightful.
Not only does he come with a strong academic background and extensive management experience, he also strongly believes in teamwork.
Prior to this, Mohta was Head of Marketing of a leading cement brand, and had a fruitful stint. He’s persistent, believes in bringing out the best in others, and is extremely sharp and focused.
He believes in living a balanced life, and truly brings a level of sportsmanship to his work, that defines his entrepreneurial skills.
Cement production in India is growing rapidly
Cement production increased at a CAGR of 6.44 per cent to 282.79 MT over FY07–16.
As per the 12th Five-Year Plan, production is expected to reach 407 MT by FY17.
In August 2016, cement production in the country increased by 3.1 per cent in comparison to 1.4 per cent in July 2016.