Biomass vacuum boiler

The invention discloses a biomass vacuum boiler and relates to the technical field of boilers. The biomass vacuum boiler comprises a boiler body, a boiler furnace, a combustor, a smoke tube bundle, abaffle and a heat exchanger. The boiler furnace is arranged on the lower portion of the interior of the boiler body, and the heat exchanger is arranged on the upper portion of the interior of the boiler body. The boiler body communicates with a vacuum pump, and the inner wall of the boiler body and the outer wall of the boiler furnace form a heat exchanging cavity. One end of the boiler furnace communicates with the combustor, and the other end of the boiler furnace communicates with a reversal chamber. The baffle is arranged on the outer side of the boiler body, and the baffle and the outer wall of the boiler body from a recovering cavity. A smoke outlet hole is formed in the outer side of the recovering cavity. One end of the smoke tube bundle communicates with the reversal chamber, andthe other end of the smoke