Transporting more material over a smaller footprint

India implemented a five-year plan to remedy its issue with power deficits—which are over 20% at times of peak demand—and in an effort to meet the power requirements, the country’s National Thermal Power Corporation adopted a multi-pronged growth strategy to set up joint ventures with state electricity board power stations. NTECL (NTPC Tamil Nadu Energy Company Limited) is one such project. It is a joint venture company consisting of NTPC and TNEB that set up a port-based 3 x 500 MW power station at Ennore, which is 45 km north of Chennai in India.

I have never seen a pipe conveyor running at 6.2 m/s , which is faster than Indian freight trains. it’s the Longest pipe conveyor I’ve ever seen.
— NTECL Chief Engineer

NTECL Project
At NTECL, coal for the power station is received from the Ennore port and conveyed to the plant, crossing creeks, fishing habitats, sea backwaters and a main railway line that connects two major cities. The specifications drawn up for the coal conveying system had options to traverse the 4.5 km stretch by trough, totally enclosed conveyor or by pipe.
The conveying system was conceived in order to unload coal from Capsize/Panamax vessels and transport it to the power station in line with an unloading of 4,000 tph to the crusher house located inside the plant. This warranted an efficient system with a reduced environmental footprint.

FLSmidth initiative

Overcoming challenges that were unthinkable even ten years ago became a reality in 2006 when the pipe conveyor concept was created. Through FLSmidth’s collaboration with the client and high level of expertise, meeting the Indian power industry’s need for efficient mega power projects with greener development paths and reduced CO2 emissions was easily achievable.

FLSmidth was the frontrunner in this project, standing out against competition from conventional conveyor and pipe conveyor companies. The company’s track record of installing efficient pipe conveyors around the world helped to secure this project.

Engineering excellence

After the order was placed, there were challenges and critiques from many Indian industries that opposed the introduction of pipe conveyors, since trough conveyors had been the preferred method for many years.

FLSmidth overcame all challenges, illustrating its engineering capabilities at the design, testing and construction stages. Every component of the system was critically examined based on application and was sourced from globally renowned OEM to ensure a reliable operating system. Close cooperation with FLSmidth’s global engineering and technology teams made this possible.

FLSmidth used a number of engineering tools, such as computational simulation techniques for belt design and the testing of the belt at FLSmidth’s Wadgassen location for collapsibility and stiffness. Drive controls were custom-built and variable frequency driven for a smooth start-up sequence to ensure the success of this system.

The entire conveyor system was checked for dynamic analysis and audited for all critical components by Dr. Gabriel Lodewijks of Delft University in Holland. This included a discrete element model for designing chutes at transfer points to achieve the life expectancy of the belt and smooth material flow. The system was also provided with adequate safety interlocks to prevent surge loads from the presiding system for smooth operation and an accident-free working zone.

Project execution

During execution, FLSmidth adopted several unique approaches, not only in design but also in construction, fabrication and belt laying. These included pulling the belt and installing the entire length in one go by pre-splicing for full length, which saved more than three months on the schedule. Construction activities had faced many challenges from the start, including casting foundations in seawater-logged areas, crossing local fishing hamlets and protecting existing vegetation.
The entire project was handled locally by the FLSmidth India team, and the project was trail commissioned in 2013.

Summary

The NTECL Pipe Conveyor Project is a classic example of FLSmidth's engineering excellence and its innovative approach and quality execution. This forerunner approach has created a global benchmark resulting in demand for environmentally clean material handling systems.
By opting to use a pipe conveyor, NTECL gained optimal power consumption per ton of coal conveyed, upheld land requirements and created a dust-free environment. This system was commissioned in 2013, just as global ports began looking for the faster turnaround of ships.
FLSmidth’s conveyor system addressed NTPC’s initiative in line with global standards and in complete harmony with environment and nature.

CONTACT: Bhaskar Ramamurthy