The waste heat boiler flue is composed of a distribution header, a lower header, a tube group, and an upper header.

         Boiler feed water is drawn from the boiler drum into the distribution header. In order to prevent the temperature deviation of each part of the header, the distribution header and the lower header are introduced by dispersing downcomers. After the water enters the lower header, it is dispersed into 132 φ42×4 The heating surface of the circular flue with a pitch circle of φ2400mm composed of seamless steel pipes and 6mm thick flat steel, then produces a mixture of soda and water enters the upper header, and is introduced into the drum by the riser.

         In order to keep the header from the flame zone, the lower part of the tube bundle is a U-shaped bend, and the angle between the flue at the furnace mouth section and the horizontal is 55 degrees.

         In order to prevent the flue from being deformed, a reinforcement ring is provided at an appropriate position on the flue.

    The flue pipe group of each section of the oblique section of flue, the oblique section of flue, the last section of flue, and the last section of flue is composed of a distribution header, a lower header, a tube group, and an upper header.

Boiler feed water is drawn from the drum into the distribution header. In order to prevent the temperature deviation of the various parts of the header, the distribution header and the lower header are introduced by dispersing downcomers. After the water enters the lower header, it is dispersed into 132 φ42×4 The circular flue heating surface with a pitch circle of φ2636mm, composed of seamless steel pipes and 6mm thick flat steel, produces a mixture of soda and water into the upper header, and is introduced into the drum by the riser.

         In order to prevent the flue from being deformed, a reinforcement ring is installed at the appropriate position on the flue. In order to facilitate maintenance, manholes are also provided in the flue. The material of header and pipe are both 20.