BHEL develops fuel flexible supercritical boilers; a look at Indian boiler market

AT A time when the country is grappling with severe coal shortages resulting in long outages, Bharat Heavy Electricals Ltd (BHEL) has developed a super critical boiler with fuel flexibility of indigenous and imported coals, which will end uncertainties regarding coal shortages.

The boiler can run run on both...

domestic as well as imported coal, a development that would provide more flexibility for power generators.

Super critical boilers have higher efficiency.

According to the company, the new boiler can work over the entire range of blending ratios and “would protect the project developer against the vagaries in coal availability, thereby providing him with an opportunity to operate the plant throughout the year”.

Bharat Heavy Electricals Ltd (BHEL), a leading power equipment maker, has been designing boilers for three decades.

According to BHEL, the new boiler would provide developers with much needed freedom regarding the ratio of blending as well as the characteristics of the domestic and imported coal to be blended.

Due to dwindling supply of coal a number of Indian companies have either resorted to operating the plant on part load due to non-availability of domestic coal or make up for the shortfall by blending indigenous coal with imported coal.

The performance of power equipment is dependent on the coal being fed to the power plant.

Based on BHEL's extensive in-house experience of working with a great variety of indigenous as well as imported coals over the years, the Maharatna PSU has developed a the new boiler with fuel flexibility of indigenous and imported coals.

BHEL is now ready to offer the new boiler design to overcome these issues, the company said.

This new boiler design is based on a unique combination of indigenous and imported coals but is capable of firing both extremes of 100 percent domestic coal as well as 100 percent imported coal.

It will provide developers with much needed freedom regarding the ratio of blending as well as the characteristics of the domestic and imported coal to be blended. This enables the boiler to work over the entire range of blending ratios and would protect the project developer against the vagaries in coal availability, thereby providing him with an opportunity to operate the plant throughout the year, BHEL added.

BHEL has a coal research centre at Tiruchirapally plant, which will be used to identify the unique combination of blended coal after carrying out the analysis of imported and domestic coal samples supplied by the customers. The associated boiler auxiliaries, also manufactured by BHEL, will be designed to accommodate the variation during firing of different type of fuels.

Addressing today's environment where thermal power plants are starved for fuel and developers face severe uncertainties regarding the availability of domestic and imported coals, BHEL's new design with fuel flexibility will be a major step forward in this direction, the company said.

This new boiler design is based on a unique combination of indigenous and imported coals but is capable of firing both extremes of 100 percent domestic coal as well as 100 percent imported coal.

It will provide developers with much needed freedom regarding the ratio of blending as well as the characteristics of the domestic and imported coal to be blended. This enables the boiler to work over the entire range of blending ratios and would protect the project developer against the vagaries in coal availability, thereby providing him with an opportunity to operate the plant throughout the year, BHEL added.

BHEL said it has a coal research centre at its Tiruchirapally plant, which will be used to identify the unique combination of blended coal after carrying out the analysis of imported and domestic coal samples supplied by the customers. The associated boiler auxiliaries, also manufactured by BHEL, will be designed to accommodate the variation during firing of different type of fuels.

Addressing today's environment where thermal power plants are starved for fuel and developers face severe uncertainties regarding the availability of domestic and imported coals, BHEL's new design with fuel flexibility will be a major step forward in this direction, the company said.

A supercritical steam generator is a type of boiler that operates at supercritical pressure, frequently used in the production of electric power. In contrast to a subcritical boiler, a supercritical steam generator operates at pressures above the critical pressure — 3,200 psi or 22 MPa — in which bubbles can form. Instead, liquid water immediately becomes steam. Water passes below the critical point as it does work in a high pressure turbine and enters the generator's condenser, resulting in slightly less fuel use and therefore less greenhouse gas production.

Technically, the term "boiler" should not be used for a supercritical pressure steam generator as no "boiling" actually occurs in the device.

Boiler markets in India have been growing continuously for past few years with a CAGR of

24.53 percent. While the demand outlook is favourable, the domestic BTG industry is faced with strong competition from original equipment manufacturers (OEMs) based in China, as several private sector players have preferred to import boiler-turbine-generator (BTG) sets from China on the grounds of relatively faster delivery schedule and competitive cost of sourcing.
According to 17th Electric Power Survey Report: The electrical energy demand for 2016–17 is expected to be at least 1392 Tera Watt Hours, with a peak electric demand of 218 GW. The electrical energy demand for 2021–22 is expected to be at least 1915 Tera Watt Hours, with a peak electric demand of 298 GW which will increase in future energy requirement.

For the period 2000-2013 total imports in boiler equipment grew continuously at a CAGR of 29.63 percent in terms of lakh rupees and at a CAGR of 26.62 percent in terms of quantity. Boiler markets in India have been growing continuously for past few years with a CAGR of 24.53 percent. According to Department of Heavy Industries annual report 2009-2012; India's Boiler Production during 2007-08 was Rs. 8231.34 crore with a capacity addition of 9263MW. During 2008-09, it was Rs. 10153.94 crore with a capacity addition of 3453MW.

Some of the supercritical projects under execution in the public sector include: NTPC (capacity 2640MW); APGENCO (Andhra Pradesh Power Generation Corporation) (capacity 1600MW); MSPGCL (Maharashtra State Power Generation Company, 1980MW); RRUVNL (Rajasthan Rajya Vidyut Utpadan Nigam Ltd, 1320MW); KPCL (Karnataka Power Corporation, capacity 700MW).

Supercritical technology is gaining prominence in the Indian market. During the Eleventh Plan, the share of supercritical technology was 14 percent, while in the Twelfth Plan the share was over 60 percent. Indian players, as well as the global players focusing on the Indian market, have put in place facilities to manufacture products based on supercritical technology.