NOVELTY - A semi-water gas producer for solid biomass comprises furnace body (1) capable of constructing a hearth, and transmission mechanism equipped in upper of furnace body (1), spiral feeder (11), ash chamber (12) and spiral extractor (17); where an insulating layer (2) and refractory layer (3) are equipped in the inner wall of furnace body (1); furnace body (1) is equipped with a semi-water gas outlet (5) and detection port (6); lower part of furnace body (1) is connected to the ash chamber (12), and a cooling water tank (13) is equipped outside the ash chamber (12).    USE - The semi-water gas producer is useful for solid biomass (claimed).    ADVANTAGE - In the semi-water gas producer, continuity and stability for gasification process can be ensured by feeding and discharging continuously; and the vapor participated in gasification reaction is generated by residual heat, such that utilization ratio of carbon element is improved, and gasification rate of solid biomass is improved; compared with the gasification furnace having the same section, gasification intensity is improved to 1.5-2.0 times, and heat value of combustible gas is doubled.    DETAILED DESCRIPTION - A semi-water gas producer for solid biomass comprises furnace body (1) capable of constructing a hearth, and transmission mechanism equipped in upper of furnace body (1), spiral feeder (11), ash chamber (12) and spiral extractor (17) equipped in lower part of the spiral feeder (11); where an insulating layer (2) and refractory layer (3) are equipped in inner wall of furnace body (1); surface of refractory layer (3) is a curved surface for which middle part of hearth is showed in girdled shape; a spiral heat exchanging tube (4) is equipped in refractory layer (3); furnace body (1) is equipped with a semi-water gas outlet (5) and detection port (6); upper part for hearth constructed by the furnace body (1) is equipped with a dentoid harrow (7) for refining material, and the harrow (7) is driven by transmission mechanism; lower part of furnace body (1) is connected to the ash chamber (12), and a cooling water tank (13) is equipped outside the ash chamber (12); the ash chamber (12) is equipped with a gasification agent inlet (14), and its bottom is equipped with an ash outlet (15), it is further equipped with a valve (16) and connected to the spiral extractor (17); and gate bar (18), which is matched to transmission bevel gear (19) and roller (20), is equipped in the interface between hearth and ash chamber (12).    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of a semi-water gas producer for solid biomass.    Furnace body (1)    Insulating layer (2)    Refractory layer (3)    Spiral heat exchanging tube (4)    Semi-water gas outlet (5)    Detection port (6)