In the cold days of early winter, Tangshan, Hebei is pierced by biting chill. As the bucket-wheel machine, like a "steel behemoth," rolls and grabs, pitch-black coal is continuously conveyed to the raw coal bunker, delivering a stable supply of fuel for the power plant's sustained generation. Recently, the coal feeding of the coal handling system of the Datang International Douhe 2×660 MW cogeneration project, in which PowerChina Nuclear Engineering Company participated in construction, was successfully completed, providing strong support for winter heating in the Tangshan area.

Technology Leads the Way, Overcoming Difficulties

The Datang International Douhe 2×660 MW coal-fired cogeneration equal-capacity replacement project is invested in and constructed by Datang International Power Generation Co., Ltd. The plant site is located in Kaiping District, Tangshan City, Hebei Province, on the west bank of Douhe Reservoir. The project builds two 2×660 MW domestically produced ultra-supercritical coal-fired cogeneration wet-cooling turbine generator units, with simultaneous construction of flue gas dust removal, desulfurization, and denitrification facilities.

The project is listed as a major project and key construction project in the "14th Five-Year Plan" of Hebei Province and Tangshan City. As one of the main heat sources in the region, the project is expected to generate 5.9 billion kWh of electricity annually after completion, with a maximum heating capacity of 28 million square meters, providing strong support for Hebei Province's strategy of accelerating the building of a strong province with new energy and for Tangshan City's energy structure adjustment and green transformation development. It is of great significance for alleviating winter heating pressure in Tangshan, serving economic and social development, and helping achieve carbon peaking and carbon neutrality.

Because the single-unit engineering construction of the dumper area of the Douhe thermal power project is highly technical, has many unsafe factors, and is difficult to construct, the foundation pit depth elevation of the dumper area is minus 23.85 meters, with local depth reaching minus 25.45 meters, setting a record for deep foundation pit construction adjacent to a water source in Tangshan City. The layout of the foundation pit is restricted by some existing buildings, making it impossible to adopt sectional sloping, which increases the vertical depth of the foundation pit. This area is adjacent to Douhe Reservoir and is rich in groundwater resources. Construction faces difficulties such as high groundwater level, large aquifer thickness, and strong permeability of sandy soil layers, which have a significant impact on deep foundation pit construction.

Management Optimization, Quality and Efficiency Improvement

The schedule is a military order. Facing unprecedented difficulties during construction, the Douhe Project Department, together with the owner unit and the supervision unit, held more than 70 expert meetings, on-site meetings, and special meetings to conduct in-depth analysis and implement precise measures. Cadres and employees of the project department worked day and night, joining forces to tackle difficulties, and adopted effective measures such as optimizing the dewatering and cement pile construction plans, overcoming multiple difficult problems in safety, quality, and schedule, including dewatering, sidewall quicksand, and hole collapse. The operation involved a total of 364 slope protection piles, 1,430 anchor cables, and 84 drainage wells, with cumulative earthwork excavation of 130,000 cubic meters, ultimately eliminating safety risks and completing the milestone on schedule.

The coal handling system of the Douhe project is newly built on the original site while demolishing the coal handling system buildings of Units 7 and 8 of the old plant, and a new coal water treatment station and coal handling comprehensive building are also built. At the same time, this year's winter heating task must be ensured. It is characterized by a tight schedule, narrow working areas, limited deployment of large machinery, a large number of single buildings, and complex cross-operation conditions.

Success comes from refined management. In this coal feeding operation, the project department organized meticulously and all disciplines worked collaboratively, conducting a comprehensive and detailed inspection and commissioning of the coal handling system in advance to ensure that the equipment was in optimal operating condition. As the coal feeding order was issued, the equipment of the coal handling system started up in an orderly manner. The belt conveyor operated smoothly, and the coal crusher worked efficiently, continuously conveying coal to the coal bunker.

The safety management team of the Douhe Project Department, based on job characteristics, always abided by job responsibilities and consistently adhered to the guideline of "safety first, prevention foremost, comprehensive management," building a dual prevention mechanism, identifying safety risks in each position and each link in advance, achieving full participation in job risk analysis and full mastery of prevention and control measures by all staff, and promoting the efficient operation of the "dual system" construction.

Party Building Leads, Cohesion and Strength

Under the strong leadership of the company's Party Committee, the Party branch of the Douhe Project Department of PowerChina Nuclear Engineering Company adheres to a problem-oriented approach, combines key Party building tasks with difficult development issues, makes full and flexible use of carriers, highlights precise efforts, promotes Party organization activities centered on the center and serving the overall situation, innovates work ideas, expands integration paths, and resolves pain points, difficulties, and bottlenecks in engineering construction.

Turning the fighting fortress role of grassroots Party organizations into practical actions that support engineering construction is a "golden key" found by the Party branch of the Douhe Project Department in the construction of the coal handling system. The project Party branch deeply integrates the company's "6346" Party building work method with production and operation, takes "six transformations," "three major spirits," "four major brands," and "six capabilities" as the starting points, solidly implements the "dual guidance and dual construction" Party building project, strives to create a distinctive Party building brand, takes production and operation needs as Party building work requirements, and uses Party member demonstration posts as "points," Party member assault teams as "lines," and Party member responsibility areas as "surfaces," adopting measures such as "mentoring and passing on experience" and key assistance, creating a strong atmosphere of undertaking work and starting businesses with an enterprising and motivated work style.

Go all out to ensure heating, and do not forget the original intention to warm thousands of homes. The builders of the Douhe Project Department of PowerChina Nuclear Engineering Company will uphold the management philosophy of "planning when doing projects and standards when doing work," and with greater enthusiasm and a rigorous attitude, ensure the safety and stability of the heating period, establishing the brand image of a responsible central enterprise in the century-old "industrial town."

Panoramic view of the Datang Douhe project

The bucket-wheel machine is operating

Coal feeding operation of the bucket-wheel machine