According to reports, France’s Alstom and Switzerland-based Foster Wheeler AG are frontrunners for a possible partnership with Bharat Heavy Electricals Ltd (BHEL) in the circulating fluidised bed combustion (CFBC) boiler segment.
This is a technology where the state-owned equipment firm is not considered as strong as competitors in the domestic market such as Thermax and ThyssenKrupp India.
With distinct commercial advantages in the long run and its credentials as a clean carbon platform, CFBC boilers are expected to be increasingly used for power generation as well as for industrial applications in the future, with a projected domestic market potential of around 8,000 MW per annum.
BHEL officials indicated that the company was in various stages of talks with both Alstom and Foster Wheeler for a partnership in the large CFBC boiler segment.
Unlike in the case of coal that is powdered, pulverised and then burnt in a furnace, the CFBC boilers have the advantage of fuel flexibility.
These boilers can also be operated with non-coal fuel options such as lignite, bagasse and straw.
The advantage accruing from clean-coal platform will be by way of fuel flexibility to burn a variety of fuels — coal, lignite, coal washery rejects, biomass and waste materials — at a low combustion temperature.
While BHEL does have some in-house expertise in commissioning small CFBC sets of 125 MW, the state-owned company hopes to design and develop large-sized CFBC boilers in the technology partnership that it is trying with Alstom and Foster Wheeler.
Early last year, BHEL had commissioned its first unit of 250 MW lignite-powered CFBC boiler at Neyveli Lignite Corporation complex in Tamil Nadu, after having supplied two 125 MW CFBC boiler units for Surat lignite power project through a technical collaboration with Germany’s AE&E Lentjes.
Typically, in the CFBC boilers, fluidised beds suspend solid fuels in upward-blowing jets of air during the combustion process, resulting in a stormy mixing of gas and solids.
The tumbling action, quite like a bubbling fluid, provides more effective chemical reactions and heat transfer. The technology was adapted to burn petroleum coke and coal mining waste for residual power generation in the early 1980s in the US, where regulations were in place that offered special incentives to the use of renewable fuels and waste fuels.
In the early 1990s, the technology spread to other parts of the world, especially proving well suited for burning fuels that are difficult to ignite, including petroleum coke and anthracite, low quality fuels like high ash coals and coal mine wastes, and fuels with highly variable heat content, including biomass and mixtures of fuels.