Process for carbonizing wood residues and producing activated carbon
AssigneeCommonwealth Scientific and Industrial Research Organization
InventorPaul Y H Fung
Life of this patent
Estimating the term…
Abstract
An apparatus and process for preparing activated carbon from a wood or wood residue feedstock using fluidized bed technology. The fluidized bed apparatus has a number of wood residue inlets that allow differing residence times in the fluidized bed apparatus appropriate for the wood or wood residue feedstock to be carbonized. The carbonized material may then be activated to form activated carbon.
Claims16
A process for carbonizing wood residues to produce charcoal, said wood residues including wood or woody-type particles of varying size and/or moisture content, the process including the steps of feeding the wood residue to a fluidized bed having a plurality of wood residue inlets, the wood or woody-type particles of varying size and/or dryness being fed to differing ones of the plurality of wood residue inlets according to an expected time for carbonization for said wood or woody-type particles, the fluidized bed including a bed of inert particulate material fluidized with or having injected therein a gas or gas mixture containing an oxidizing gas, carbonizing the wood residues in the fluidized bed under reaction conditions selected such that volatile components in the wood residues are removed during carbonization and are burned in or above the bed or in an afterburner to thereby supply the heat requirements for carbonization and separating charcoal from the inert particulate material.
An apparatus for carbonizing wood residues to produce charcoal including a fluidized bed reactor having a plurality of wood residue inlets for supplying wood residues including wood or woody-type particles of varying size and/or moisture content, a discharge outlet for removing fluidized bed contents from the fluidized bed and at least one fluidizing gas inlet, characterized in that each one of said plurality of wood residue inlets is positioned at different locations with respect to said discharge outlet and that residence time of or woody type particle in the fluidize bed reactor is dependent upon the inlet through which the wood or woody type particle is fed to the fluidized bed reactor.
An apparatus for producing activated carbon including:
- a furnace;
- a reactor positioned inside the furnace, the reactor including solids inlet means for supplying solids to the reactor and gas inlet means for supplying gas to the reactor, at least one pipe connected to the gas inlet means of the reactor, said at least one pipe having at least a portion of its length extending within the furnace whereby gas flowing through said at least one pipe to the reactor is heated to an elevated temperature by the furnace;
- and
- a gas manifold inside the furnace, the gas manifold having an inlet and a plurality of outlets, each of the plurality of manifold outlets having respective ones of a plurality of pipes extending therefrom, the plurality of pipes being connected at their other ends to the gas inlet means of the reactor.
A process for carbonizing wood residues to produce activated carbon, said wood residues including wood or woody-type particles of varying size and/or moisture consent, the process including the steps of:
- feeding the wood residue to a first fluidized bed having a plurality of wood residue inlets, the wood or woody-type particles of varying size and/or dryness being fed to differing ones of the plurality of wood residue inlets according to an expected time for carbonization for said wood or woody-type particles, the first fluidized bed including a bed of inert particulate material fluidized with or having injected therein a gas or gas mixture containing an oxidizing gas;
- carbonizing the wood residues in the fluidized bed under reaction conditions selected such that volatile components in the wood residues are removed during carbonization and are burned in or above the bed or in an afterburner to thereby supply the heat requirements for carbonization;
- separating charcoal from the inert particulate material of the first fluidized bed;
- adding particulate material to a second fluidized bed reactor to form a bed of particulate material;
- adding said charcoal to said second fluidized bed reactor and fluidizing the bed;
- activating the carbon feedstock by adding superheated steam to the fluidized bed to produce activated carbon;
- and
- recovering activated carbon from the bed.
Dependencies are inferred from the claim text.