Biswajit Dhar, Senior Vice President (Technology and Research Centre), UltraTech Cement
Several energy saving initiatives taken by Ultratech has got their manufacturing plants not only ready to reap the benefits of PAT initiatives but have also led to significant savings for the company. Biswajit Dhar, Senior Vice President (Technology and Research Centre), UltraTech Cement, talks about the initiatives with ICR. Excerpts from the interview.
How do you rate your company when it comes to energy efficiency?
Ultratech Cement plants have been at the forefront in terms of energy efficiency and have been the recipient of various awards in this domain. Some of its performance parameters are comparable to global standards and most of the plants are among the best performers by Indian standards.
What operational measures have you taken to conserve energy in your plant?
Energy conservation is a key focus area for us. Operational measures towards energy conservation include constant monitoring to reduce downtime, reducing operational inefficiencies ensuring reliability of equipment, optimising productivity, minimising leakages, monitoring day-to-day energy consumption, and sharing of best practices.
Have you done any modifications lately to help conserve energy?
Some of our initiatives include upgradation of pyro-process with modification of preheaters at Reddipalayam Cement Works and Jafrabad Cement Works. We have retrofitted old generation clinker coolers with state-of-the-art coolers to reduce thermal and electrical energy consumption in these two plants, and the process is under implementation at Awarpur Cement Works, Rajashree Cement Works and Hirmi Cement Works. Apart from this, other initiatives like addition of pre-grinders, separators, grinding systems has also been taken up at various units to improve upon the operational performance.
We have used CFD (Computational Fluid Dynamics) analysis and FEA (Finite Element analysis) for optimising performance of fans, cyclones, ESPs, and calciners. CFD and FEA analysis have also been used for improving combustion efficiency in kiln burner through better mixing of fuel and air. We have installed waste heat recovery systems to generate electricity from waste heat at our Tadipatri Cement Works. Similar installations are in progress at Rawan Cement Works, Aditya Cement Works, Awarpur Cement Works, and Rajashree Cement Works.
Use of alternative fuels and raw materials (AFR) has helped reduction in fossil fuel consumption and CO2 footprint. Some of these include biomass, refuse derived fuels, shredded tyres and tyre-derived fuels, and industrial wastes consisting of both hazardous and non-hazardous waste.
Other initiatives include installation of variable voltage variable frequency (VVVF) drives in areas of variable operational demand, advanced DCS control systems for enhanced operational control, installation of energy efficient lighting, etc.
What are your plans for improving energy efficiency?
We are replacing relatively low efficient equipment with energy efficient systems in a phased manner. We are constantly examining and evaluating measures to optimise clinker component per tonne of cement. Transmission losses are reduced through dedicated lines wherever applicable. Condition monitoring and proactive maintenance has helped in reduction of downtime, ensuring better availability.
Are you geared to take advantage of the PAT initiative?
Yes, we have taken several steps to reduce our energy footprint and progress towards meeting Perform Achieve and Trade (PAT) targets, in the current PAT cycle.
Were there any challenges in the purchase of RECs?
Approach of renewable purchase obligation (RPO) enforcement is not uniform across all states, and RPO is being carried forward in a few states. Restrictive measures like banking and wheeling costs discourages capital investment in renewable energy technologies. Non-uniformity in the treatment of cogeneration (WHRS) for considering it as renewable energy between states is also an issue. Proposed changes in the Electricity Act 2003 and National Tariff Policy highlighting important changes from the renewable energy perspective are awaited for better clarity.
What is your RPO target for the year and how do you plan to meet it?
We are aiming to fulfill RPO where demand notice has been issued through purchase of RECs. We have installed solar power of combined capacity equal to 2.6 MW. Possibilities to purchase/generate co-gen power (WHRS) are being explored wherever viable. Parallelly, we are evaluating various options to address RE obligations.
What is the scope of using fly ash in cement manufacture?
Fly ash has a direct impact in reduction of specific energy consumption, since it reduces clinker component in cement to a certain extent. However, use of fly ash has a few constraints. A major constraint is the availability of good quality fly ash. In certain cases, transportation cost of fly ash is a constraint when it has to be sourced from a distance. Moreover, many power plants are replacing conventional coal with petcoke or other alternative fuels. The quantity of fly ash, so generated, diminishes with this.
To what extent can IT be harnessed to save energy?
IT solutions are being used for superior production scheduling to improve PLF (Plant Load Factor). Cost analysis of different sources of energy is carried out on IT platforms. IT solutions enable in identifying idle running equipment and scope for energy optimisation. Heat and light sensing systems help in reducing electricity consumption in office buildings. IT tools are also helpful in enhancing decision making for procurement of fuels/ energy sources based on quality parameters.