Provided are: a useful bed medium for a fluidized bed with good fluidity, the bed medium being usable in a fluidized bed furnace using biomass material and coal material as fuel; and a useful bed medium for a fluidized bed with good durability, the bed medium not easily forming an agglomerate of its particles, and being resistant to collapsing. The bed medium for a fluidized bed in a fluidized bed furnace for combusting or gasifying the fuel is formed of artificially-produced spherical refractory particles containing not less than 40% by weight of Al2O3 and not more than 60% by weight of SiO2 and having an apparent porosity of not more than 5%, and a ratio by weight of agglomerated particles in the bed medium is not more than 20% after three heat treatment tests on the bed medium at 900° C. for 2 hours under coexistence with the fuel.

Provided are: a useful bed medium for a fluidized bed with good fluidity, the bed medium being usable in a fluidized bed furnace using biomass material and coal material as fuel; and a useful bed medium for a fluidized bed with good durability, the bed medium not easily forming an agglomerate of its particles, and being resistant to collapsing. The bed medium for a fluidized bed in a fluidized bed furnace for combusting or gasifying the fuel is formed of artificially-produced spherical refractory particles containing not less than 40% by weight of Al2O3 and not more than 60% by weight of SiO2 and having an apparent porosity of not more than 5%, and a ratio by weight of agglomerated particles in the bed medium is not more than 20% after three heat treatment tests on the bed medium at 900° C. for 2 hours under coexistence with the fuel.

The present invention relates to a method for treating waste material comprising organic components and low and/or intermediate level radioactive agents. The method comprises adding material comprising fibers and kaolin to the waste material in order to form a starting material, and gasifying the starting material at a temperature between 600 and 950° C. to form a gaseous fraction and a solid fraction comprising low and/or intermediate level radioactive agents, gasification residues of the organic components and metakaolin. The present invention also relates to a use of mate-rial comprising fibers and kaolin.

The invention provides a system for pyrolysing organic waste. The system comprises a conical housing (4) configured to temporarily, substantially hermetically, enclose the waste and a mixing device provided with a drive shaft rotatably mounted relative to the housing and a conical mixing body (25) configured inside the housing to fluidise the waste, which mixing body fixedly attached substantially does not touch the housing. The system further comprises heating means (24) for heating the side wall of the housing. This system makes it possible to carry out the processing of organic waste in a batch process. The mixing body prevents a portion of the waste from sticking together by fluidising the waste and keeping it fluidised, whereby the heat generated by the heating means can gradually spread through the waste inside the housing.

The invention provides a system for pyrolysing organic waste. The system comprises a conical housing (4) configured to temporarily, substantially hermetically, enclose the waste and a mixing device provided with a drive shaft rotatably mounted relative to the housing and a conical mixing body (25) configured inside the housing to fluidise the waste, which mixing body fixedly attached substantially does not touch the housing. The system further comprises heating means (24) for heating the side wall of the housing. This system makes it possible to carry out the processing of organic waste in a batch process. The mixing body prevents a portion of the waste from sticking together by fluidising the waste and keeping it fluidised, whereby the heat generated by the heating means can gradually spread through the waste inside the housing.

A multi-stage product gas generation system converts a carbonaceous material, such as municipal solid waste, into a product gas which may subsequently be converted into a liquid fuel or other material. One or more reactors containing bed material may be used to conduct reactions to effect the conversions. Unreacted inert feedstock contaminants present in the carbonaceous material may be separated from bed material using a portion of the product gas. A heat transfer medium collecting heat from a reaction in one stage may be applied as a reactant input in another, earlier stage.

A multi-stage product gas generation system converts a carbonaceous material, such as municipal solid waste, into a product gas which may subsequently be converted into a liquid fuel or other material. One or more reactors containing bed material may be used to conduct reactions to effect the conversions. Unreacted inert feedstock contaminants present in the carbonaceous material may be separated from bed material using a portion of the product gas. A heat transfer medium collecting heat from a reaction in one stage may be applied as a reactant input in another, earlier stage.

Disclosed herein are a fluid sand falling type circulating fluidized bed boiler with a plurality of risers for preventing erosion and corrosion of water tubes and increasing combustion efficiency, and a method of operating the same. The fluid sand falling type circulating fluidized bed boiler with a plurality of risers includes a boiler section into which fuel and oxidizer are injected, a riser section connected to the boiler section so that the fuel and fluid sand supplied from the boiler section are introduced from the bottom of the riser section and flow up, and a relay section provided on the boiler section to supply the fluid sand having passed through the riser section to the boiler section, wherein the fuel is injected from the top of the boiler section and burned while flowing down therein.

A pyrolysis and gasification system produce a synthesis gas and bio-char from a biomass feedstock. The system includes a feed hopper that has a flow measurement device. The system also includes a reactor that is operable in a gasification mode or a pyrolysis mode. The reactor is configured to receive the biomass feedstock from the feed hopper. The reactor is operable to provide heat to the biomass feedstock from the feed hopper to produce the synthesis gas and bio-char. The system also includes a cyclone assembly. The produced synthesis gas including the bio-char is fed to the cyclone assembly. The cyclone assembly removes a portion of the bio-char from the synthesis gas.

A pyrolysis and gasification system produce a synthesis gas and bio-char from a biomass feedstock. The system includes a feed hopper that has a flow measurement device. The system also includes a reactor that is operable in a gasification mode or a pyrolysis mode. The reactor is configured to receive the biomass feedstock from the feed hopper. The reactor is operable to provide heat to the biomass feedstock from the feed hopper to produce the synthesis gas and bio-char. The system also includes a cyclone assembly. The produced synthesis gas including the bio-char is fed to the cyclone assembly. The cyclone assembly removes a portion of the bio-char from the synthesis gas.