Process and system for wastewater solids gasification and vitrification
AssigneeMicroGas Corporation
InventorDennis P. Moraski
Life of this patent
Estimating the term…
Abstract
A process for gasifying solid organic matter from wastewater sludge involves dewatering the sludge to a solids content of at least 35% by weight using a combination of centrifugation, microwave heat exchange and screw press separation. The denatured solids are than at least partially pyrolyzed by passing through a heated inclined screw auger. The pyrolysis solids, tars and gases are then gasified by exposure to a high intensity microwave field. Resulting fuel gas and char from the gasification are then separated, with the char then being combusted in a cyclonic char burner to produce vitrified ash and process heat. Fuel gases are cleaned and then burned in internal combustion engines for the generation of electricity and process heat.
Claims27
A process for gasifying an aqueous sludge containing organic waste solids, comprising the steps of:
- dewatering the sludge containing organic waste solids to a solids content of at least 35% by weight;
- at least partially pyrolyzing the dewatered sludge to produce pyrolysis products;
- gasifying the pyrolysis products after pyrolysis by exposing the pyrolysis products in the absence of oxygen to microwave radiation to produce uncombusted fuel gas and char;
- separating the uncombusted fuel gas and char;
- recovering the uncombusted fuel gas;
- and
- combusting the char for process heat.
A process for gasifying solid organic waste matter, comprising:
- introducing organic waste matter into a reactor;
- generating microwave radiation having a field density of greater than 1,000 watts/cubic foot;
- anoxically exposing the organic waste matter within the reactor to the generated microwave radiation at a temperature of at least 1,800° F. to 2,200° F. to at least partially gasify the organic waste matter to produce uncombusted fuel gas and char;
- and
- collecting the uncombusted fuel gas and the char from the reactor.
A process for gasifying solid organic waste matter, comprising the steps of:
- at least partially pyrolyzing the solid organic waste matter to produce pyrolysis products;
- gasifying the pyrolysis products after pyrolysis by exposing the pyrolysis products to microwave radiation to produce uncombusted fuel gas and char;
- and
- recovering the char and uncombusted fuel gas.
A system for use in gasifying an aqueous sludge containing organic waste solids, comprising:
- a dewatering unit capable of dewatering the sludge containing organic waste solids as necessary to a solids content of at least 35% by weight;
- a pyrolysis unit in fluid communication with the dewatering unit to at least partially pyrolyze the dewatered sludge to produce pyrolysis products;
- a microwave generator that generates microwave radiation having a field strength of greater than 1,000 watts per cubic foot;
- a gasification reactor in fluid communication with the pyrolysis unit to receive the pyrolysis products;
- a wave guide coupled to the microwave generator and the gasification reactor to expose the received pyrolysis products after pyrolysis to the generated microwaves, producing uncombusted fuel gas and char;
- and
- a gas/solid separator in fluid flow communication with the gasification reactor for separating the uncombusted gas and the char produced in the gasification reactor.
Dependencies are inferred from the claim text.