I. Positioning and Core Role of the 50T Start-up Boiler

In a 2×1000MW ultra-supercritical large-scale thermal power project, the 50T start-up boiler is not merely an auxiliary component of the main unit, but rather a core pre-installed device ensuring the safe and efficient startup of a megawatt-class unit. The main steam parameters of ultra-supercritical units far exceed those of conventional subcritical units, requiring extremely high temperature and pressure stability of the steam during cold starts. Relying solely on the main unit's own water circulation system makes it difficult to quickly produce qualified steam that meets the requirements for turbine start-up, pipe warm-up, and generator warm-up. The core value of the 50T start-up boiler lies in its ability to independently produce auxiliary steam with matching parameters before the main unit ignition. This significantly shortens the main unit's startup time, reduces fuel consumption during startup, and prevents thermal shock caused by mismatched steam parameters, effectively protecting thick-walled critical components such as the turbine rotor and main steam pipes, thus extending the overall service life of the main unit.

II. Technical Characteristics of the 50T Start-up Boiler Adapted to 1000MW Units

Designed to meet the specific needs of 2×1000MW ultra-supercritical units, this type of 50T start-up boiler features extensive optimizations, fundamentally different from ordinary small-tonnage industrial boilers. It generally adopts a modular integrated design, with core components such as the furnace, heating surfaces, and burners pre-assembled in the factory. Upon arrival at the project site, only interface connection needs to be completed for commissioning. Compared to traditional bulk boilers, this shortens the installation cycle by nearly half and significantly reduces on-site construction safety risks. To match the start-up curve of ultra-supercritical units, its steam parameters can be flexibly adjusted over a wide range, stably outputting high-temperature, high-pressure steam that meets the main unit's start-up requirements. It is also equipped with a low-NOx combustion system, easily meeting the ultra-low emission standards required for current thermal power projects, fully complying with clean production environmental protection requirements.

III. Standard Commissioning Procedures and Key Control Points for the 50T Start-up Boiler

The commissioning of the 50T start-up boiler follows strict operating procedures, with each step directly affecting the safety of subsequent main unit startup. Before ignition, the interlocking protection of the entire system must be verified, including simulation tests of all safety devices such as water level protection, pressure protection, and flameout protection. Simultaneously, individual test runs of auxiliary equipment such as feedwater pumps, induced draft fans, and oil pumps must be completed to confirm that all equipment is in normal standby condition. During the water filling stage, the difference between the feedwater temperature and the boiler drum wall temperature must be strictly controlled to not exceed the specified threshold to avoid excessive initial thermal stress on thick-walled components. After ignition, the boiler water temperature should be gradually increased at a rate not exceeding 2℃/min, with real-time monitoring of boiler water quality throughout. Only when indicators such as conductivity, iron ion content, and pH value all meet the standards can steam parameters be further increased to prepare for subsequent steam supply to the main unit system.

IV. The Operational Value of the 50T Start-up Boiler for 1MW Units

The proper use of the 50T start-up boiler can bring significant comprehensive benefits to the 2×1000MW ultra-supercritical units. During the project's infrastructure commissioning phase, it can independently provide a stable steam source for pipeline purging and chemical cleaning without requiring early start-up of the main unit, significantly reducing fuel oil and plant power consumption during the commissioning phase. During routine peak-shaving start-up and shutdown of the unit, the start-up boiler can provide auxiliary steam to the shaft sealing system and deaerator in advance, making the start-up process of the main unit smoother and significantly reducing equipment losses during start-up and shutdown. Over the long term, this not only reduces the start-up cost of the unit but also effectively improves the peak-shaving flexibility of the entire power plant, enhances the unit's adaptability to grid load fluctuations, and lays a solid foundation for the long-term safe and economical operation of megawatt-class ultra-supercritical units.