Waste heat recovery: A solution for the future
UltraTech Cement is one of the earliest proponents of waste heat recovery, alternative
fuels and other environmental practices among cement manufacturers in India. It
has undertaken a voluntary strategy to reduce the impact of its operations on Climate
Change. As a member of the Cement Sustainability Initiative, it is committed to
publishing its emission data and set environmental performance targets.
Cement manufacturing is an energy-intensive process. The present situation of scarcity
of natural fuels is an ever growing concern for the cement industry. Given these
dynamics, it makes sense for cement manufacturers to adopt waste heat recovery systems
(WHRS) to meet a portion of their energy requirements.
Establishing its footprint
WHRS makes economic sense for cement companies as it enables greater energy security,
(capability to meet 20% of power requirement), improves competitive positioning,
and ensures compliance to regulatory policies (push towards use of minimum 5-10%
renewable/WHR energy in several states in India).
With improvements in technology, increased cost of power, and the pressing need
to reduce energy consumption and CO2 footprint, waste heat recovery systems have
emerged as a feasible option. However, the challenge lies in integrating a system
for waste heat recovery into the existing site without affecting the process. And
this is exactly what UltraTech Cement has successfully done. Rising energy prices
and depleting energy sources are a major challenge for the industry. UltraTech Cement
is always looking for technologies and solutions that can lower its environmental
footprint as well as be economically viable. The company is in the process of installing
waste heat recovery power plants wherever feasible.
As part of its commitment to reduce its carbon footprint, UltraTech Cement has commissioned
Waste Heat Recovery Systems at some of its units in India. It has recently commissioned
Waste Heat Recovery Systems (WHRS) at Rawan Cement Works in Chhattisgarh, Awarpur
Cement Works in Maharashtra, Rajashree Cement Works in Karnataka and Aditya Cement
Works in Rajasthan. UltraTech also has a 3.5 MW waste heat recovery plant operational
at Andhra Pradesh Cement Works, Tadipatri.
The current capacity of WHR systems at these units is as under:
• Awarpur Cement Works: 13 MW commissioned in April
• Rajashree Cement Works: 10.7 MW commissioned in April
• Rawan Cement Works: 13 MW (Pre-Heater Boiler for
additional 2 MW to be commissioned by June 2015)
• Aditya Cement Works: 10 MW (Boiler for additional
6 MW to be commissioned by March 2016)
Post the complete commissioning of the WHR power projects in these four plants,
UltraTech Cement will be one of the leaders in India in waste heat recovery systems
in cement manufacturing with a combined capacity of about 58 MW. UltraTech has adopted
the strategy of installing WHR power projects in all its operating integrated plants
and will be considering WHR right from the beginning for its upcoming projects.
Waste heat recovery is not only the cheapest source of energy but it also reduces
carbon footprint. WHR systems are now part of all new projects at UltraTech Cement.
A feasible option for the future
The average cost of a WHR plant is approximately Rs 10 crore per MW. Carbon footprint
reduction and PAT (perform achieve trade) benefit of waste heat recovery across
the five systems can be estimated after complete commissioning.
The benefits of WHR systems include carbon footprint reduction and PAT benefits,
and cost benefits with reduction in cost per unit. Thermal power cost is about Rs
4 per unit, and WHR can bring it down to Rs 0.5 per unit. As fossil fuels become
scarcer and power costs edge higher, waste heat recovery is going to be a strategic
option to gain cost leadership in manufacturing.