On April 17, the 700 MW high-efficiency ultra-supercritical circulating fluidized bed generator set of Yunneng Honghe Power Plant successfully completed 168 hours of trial operation, marking the official operation of the world's first 700 MW ultra-supercritical circulating fluidized bed boiler developed by Dongfang Electric.

After the completion of the unit, the Honghe Power Plant will have a total installed capacity of 1,300 megawatts and an annual power generation capacity of more than 8 billion kilowatt hours, which will become the largest stable power supply support point in southern Yunnan and play an important role in ensuring regional energy supply security, promoting local economic development and social stability.

The project adopts the boiler, steam turbine and generator independently developed by Dongfang Electric, among which the boiler adopts the most advanced high-efficiency ultra-supercritical circulating fluidized bed power generation technology, which has the characteristics of large single unit capacity, advanced power generation technology, high unit efficiency, excellent comprehensive benefits of energy conservation and environmental protection, and overcomes the challenges brought by lignite with high altitude, high moisture and low calorific value.

In terms of boiler development, it is the first to adopt the M-type overall structure layout of a single furnace without an external bed and four separators, and adopts large-scale furnace uniformity control technology, patented technology of all-water-cooled partition wall, and patented technology of multi-stage folded furnace structure, etc., which successfully solves key technical problems such as combustion uniformity and material uniformity of super-large furnace, secondary air penetration, and hydrodynamic safety and stability, and lays a solid foundation for operation.

The project is synchronously equipped with the flue gas desulfurization and flue gas denitrification device of Dongfang Boiler with independent intellectual property rights to achieve ultra-low pollutant emissions. Among them, flue gas desulfurization adopts the general contracting mode of engineering, and the desulfurization unit integrates the latest research results such as slurry pH cascade control and differentiated spray layer design, which is the world's first benchmark project to achieve a desulfurization efficiency of more than 99.5% by using a single tower and single cycle, and more economically and effectively realizes the ultra-low emission of high-sulfur coal flue gas.

In terms of generator development, the 700 MW generator with high parameters and high reliability developed by Dongfang Electric is adopted. The key technical indicators such as generator efficiency, short-circuit ratio and maximum continuous output are at the leading level of the same type of machine at home and abroad. The product design innovation applies advanced technologies such as stator and rotor end elastic support technology, stator end shielding technology and rotor full damping, which adapts to the new power grid operation environment and fully meets the flexible operation requirements of the unit.

In terms of steam turbine development, the latest intermediate reheat, four-cylinder, four-exhaust, wet condensing steam 700 MW steam turbine developed by Dongfang Steam Turbine is adopted. The steam turbine applies advanced fourth-generation flow technology, with excellent performance, outstanding deep peak regulation ability and load carrying capacity at high temperature, which can effectively ensure the safety of the power grid, and at the same time apply smart products to realize intelligent equipment, reduce the difficulty of operation and maintenance, and improve the operation efficiency and reliability of the unit.

The boiler was ignited for the first time on February 20 this year, the blowing pipe was completed on February 26, the first grid-connected power generation was carried out on March 21, the first full-load operation was carried out on April 5, and the 168-hour trial operation was passed on April 17. During the trial operation, the parameters of the main reheat steam reached the design value, the deviation of the heating surface at all levels was well controlled, there was no overtemperature on all heating surfaces, and the emission concentrations of soot, sulfur dioxide and nitrogen oxides reached the ultra-low emission standard.

With excellent performance parameters, stable operation performance, flexible adjustment characteristics, reliable equipment quality, and the high-quality services provided by Dongfang Electric, Dongfang Electric has successfully won unanimous recognition and high praise from the owner, the general contractor and the commissioning unit.

Dongfang Electric will continue to deepen the field of circulating fluidized bed power generation technology, and with its accumulated rich experience and innovation capabilities, it will continue to optimize existing technologies, launch more efficient and environmentally friendly boiler products that adapt to different working conditions, gather industry wisdom, overcome more energy technology problems, and contribute more to the construction of a new energy pattern of sustainable development. (This article is from the official website of Jiandao www.seetao.com it may not be reproduced without permission, otherwise it must be investigated, please indicate Jiandao.com + original link) Jiandao.com strategic column editor / Sun Fengjuan