With its acquisition of Alstom’s thermal services business in November last year, GE increased its global capability to service non-GE supplied power generation equipment. An early benefit of this expansion is a newly signed agreement with Toshiba to retrofit four of its industrial steam turbines at the POSCO Pohang Works steel manufacturing facility in Pohang, South Korea.
POSCO is a leading steel producer. The project is expected to extend the operating life of the factory’s power plant and nearly double the turbines’ ability to generate process steam used for steel production. The retrofit will enable an increase in process steam production efficiency even as the company retires the power plant’s other older generating units at the factory.
"The project will help our facility to increase the supply of process steam to 70 tons per hour, up from the current 40 tons per hour. The performance gains from these upgrades are significant" commented Mr Kwan-Soo Song, group leader of the head office of finance and investment division of POSCO.
Modernisation of the nearly 50-year-old steam turbines will blend hardware and software technology with newly designed replacements of the turbines’ internal components including a digital electro-hydraulic controller, a condition monitoring system, generator stator rewinding, generator rotor refurbishment, exciter rewinding and turbine installation.
The power plant recycles the factory’s own blast furnace gas (a waste gas created during the steel production process) to fuel the steam boilers for power generation. The factory power plant’s current total on-site generating capacity is 1079 MW and meets approximately 50 % of the factory’s internal energy requirements. The plant includes two 110 MW GT11N2 gas turbines and one 120 MW steam turbine in combined-cycle mode as well as a 100 MW steam turbine. The output of each turbine will be increased by up to 78 MW.
The components for the turbine retrofits are scheduled to be delivered to the factory in stages from February 2017, to December 2019, with retrofits scheduled to be completed between July 2017 and June 2020.
GE will be using its mobile machining equipment from China, also known as its Mobile Machine Shop, to machine the steam turbines’ newly designed internal parts.