Coal handling: The FLSmidth way

When Tata Power Decided to upgrade its coal handling facilities, it called on FLSmidth’s expertise to overcome several challenges.

In December 2008, Tata Power’s new 1.54km coal handling system unloaded and conveyed the first coal from barges to the power plant stockyard in Mumbai, India. This event marked the coming into operation of India’s most sophisticated, efficient and environment-friendly system, which includes a continuous ship unloader (CSU) and pipe conveyors supplied by FLSmidth. The project demonstrates Tata’s commitment to high-level technology and social responsibility.

Tata Power has a total installed generating capacity of over 2300MW in the form of thermal, solar, hydro and wind energy plants. In Mumbai, the company operates a 1330MW thermal power station at Trombay. Tata Power was planning to install two more units of 250MW each to cater for Mumbai City’s increasing demand. Besides, it wanted to ensure that all the units are compatible for the coal-based system. Due to governmental regulations it was necessary to install an environmentally-friendly system for unloading coal at the power plant’s jetty and conveying it to and from the stock yard. Tata Power had been working on these requirements for more than a decade before deciding to work with FLSmidth to install a cutting edge system that meets the stringent regulations and is still competitive.

FLSmidth – a preferred partner to Tata Power

In 2004, FLSmidth learned about Tata Power’s requirements for building its own jetty to unload imported coal from Indonesia for its existing power plant and for the new power plant being planned. The challenging part was to transport coal within the congested plant layout over a distance of 1540m, crossing existing power plant units, circumventing an existing flyover, passing below the high-voltage power lines, and crossing the 74m-wide Mumbai Port Trust channel, which houses chemical, gas and oil pipe lines.

In January 2006, FLSmidth was awarded an order on a semi-turnkey basis for a complete system, comprising a continuous ship unloader and two pipe conveyors (including the conveyor at the wharf), structural engineering, electrical supplies and instrumentation.

FLSmidth continuous ship unloader – a design leap

The CSU was preferred instead of a grab, because it is an environmentally-friendly machine for unloading coal at the dedicated jetty. The machine marked a design leap since the unloaders previously supplied by FLSmidth were for capacities 800tph and below. The machine was designed with a perspective to aggressively enter the port business, at the same time bringing in standardisation. Hence, it has a vertical screw of 820mm diameter, which is capable of handling up to 2000tph of coal. The horizontal arm is 21m long and the vertical arm is 16m high, while the total machine weighs 283t. It was developed, designed and sourced by FLSmidth, who also developed and tested the complete electrics including the PLC. The equipment was installed by the FLSmidth team working closely with Tata Power.

FLSmidth pipe conveyors – an engineering marvel

This installation is a classic example of a pipe conveyor application. There are two pipe conveyors of diameter 450mm: PCN-N2 (444m long) and PCN-N3 (1100m long). The pipe conveyors are designed for a speed of 4.5m/s and have a rated capacity of 1550tph. PCN-N2 receives the coal from the wharf conveyor and feeds PCN-N3 at an elevation of 40m in the junction tower. PCN-N3 has curve radii of 135m, the tightest in the world. Pipe conveyor PCN-N3 has 14 curves, one of which measures 94°. The double-pipe conveyor system is an alternative solution that replaces 14 conventional conveyors which would otherwise have been required for this application.

Before manufacturing the pipe conveyor belting, a finite element analysis was done followed by testing in the test rig at CKIT works in South Africa under simulated operating parameters and in the presence of the client, the FLSmidth team, Dr Gabriel from Delft University and belt manufacturer M/S Taeryuk, South Korea. PCN-N2 is also designed for return conveying of coal from the yard to the new power plant units. Gantries with provision for accommodating a standby pipe conveyor for bringing coal to the new plant are already in place.

The Tata Power project overcame several challenges which included space constraints, overhead high-voltage power lines and underground pipelines.

Challenges in the brownfield project

The project was full of challenges right from finalising a feasible route to carrying out the work due to space constraints, existing roads and facilities, overhead high-voltage power lines, underground cables and pipelines at the 50 year-old power plant. Several solutions were devised while executing the project, which was completed to the satisfaction of Tata Power and FLSmidth.

Maximising FLSmidth competency and experience

To date, FLSmidth has successfully installed more than 280 pipe conveyor systems worldwide, which are operating in various industrial applications, handling the easiest to the most challenging materials at 60-2000tph capacities and over lengths ranging from 60m to 8200m. FLSmidth worked closely with CKIT (South Africa) to execute the state-of-the-art system from concept to commissioning. This is the first time a system of this configuration has been installed for this application. The company’s experience from the 280 installations has helped in successfully designing and executing a dream project for TATA Power with its continued support.

One Source One Partner – a preferred approach

The system has been operational since December 2008 and a performance test was scheduled prior to the end of March 2009. In response to FLSmidth’s professional approach, Tata Power awarded another order on a single-party basis to replace a set of four conventional conveyors with two pipe conveyors. In addition, an operation and maintenance (O&M) contract for the ship unloader along with a contract for supervision of pipe conveyor maintenance has been awarded to FLSmidth.

For more information, consider visiting the following websites:
FLSmidth
Tata Power