Biomass gas fuel steam boiler

The invention discloses a biomass gas fuel steam boiler, and relates to the technical field of steam boilers. The boiler comprises a cylinder body, the cylinder body is horizontally arranged above the ground through two supporting columns, a boiler furnace inserted into the cylinder body is installed at the horizontal end of the cylinder body in a penetrating mode, a water storage cavity is formed between the boiler furnace and the cylinder body, and a reciprocating flue inserted into the water storage cavity in a penetrating mode is arranged in the cylinder body; the combustion engine is fixedly connected to one end of the cylinder body and is inserted into the furnace pipe; the feeding mechanism comprises a feeding frame fixedly communicated between the burner and the furnace pipe, and a gas feeding pipe is arranged on one side of the feeding frame. The feeding frame is arranged between the combustor and the furnace pipe, biomass solid fuel and biomass gas fuel are conveyed into the feeding frame at the sam