The SZL series biomass-fired boiler is a chain grate water tube boiler designed by ZOZEN Boiler based on advanced international technology and experience. It features a horizontal double-drum and vertical layout structure. The boiler consists of two major parts: the upper part is the heating surface and the lower part is the combustion equipment. The front of the boiler body is surrounded by water-cooled walls. The upper part is connected with drum and the lower part is connected with the header to form the combustion chamber, absorbing the radiation heat of the furnace. At the rear end, a convection tube bundle is arranged between the upper and lower drums. After the fuel is burned in the furnace, the high-temperature flue gas is swept across the convection tube bundle for the secondary return, then guided to a separately arranged economizer and finally enters the dust collector before being discharged through the chimney.