NOVELTY - Gasifying (M1) biosolids obtained from sewage sludge, involves receiving biosolids in a fluidized bed biogasifier having a reactor bed section and freeboard section; introducing gas to fluidized bed reactor to produce superficial velocity of producer gas inside the freeboard section of 0.1-3 m/second (0.33-9.84 ft/second); heating and reacting biosolids inside the biogasifier to 900-1700 degrees F (482.2-926.7 degrees C) such that a thermochemical conversion process occurs with oxygen-to-fuel equivalence ratio of 0.1-0.5 relative to complete stoichiometric combustion, where biosolids are gasified.    USE - For gasifying biosolids obtained from sewage sludge (claimed).    ADVANTAGE - The gasification-combustion process followed by energy recovery utilizes energy in biosolids and reduces or eliminates the need for use of fossil fuels to dry the biosolids. This makes the gasification system an energy-efficient and environmentally friendly solution to biosolids management.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) a fluidized bed biogasifier for gasifying biosolids obtained from sewage sludge, comprising a reactor vessel, a freeboard section, a feeder for feeding biosolids into the reactor vessel, where the feeder is configured to feed the biosolids into the reactor vessel at a biosolids fuel feed rate during steady-state operation of the biogasifier, a fluidized bed in a base of the reactor vessel, where the fluidized bed has a cross-sectional area that is proportional to at least the biosolids fuel feed rate during steady state operation such that a superficial velocity range of gas inside the freeboard section is 0.1-3 m/second (0.33-9.84 ft/second); and    (2) manufacturing (M2) the fluidized bed biogasifier for gasifying biosolids obtained from sewage sludge, involving providing a freeboard section, providing the feeder for feeding biosolids into the reactor vessel, and providing the fluidized bed in a base of the reactor vessel.