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A method and system for fueling of a burner in a direct-fired device using syngas. A gasifier produces syngas from a carbonaceous feedstock such as biomass. The syngas is fed to a syngas burner. A booster burner disposed between the gasifier and the syngas burner increases the temperature of the syn

A method and system for fueling of a burner in a direct-fired device using syngas. A gasifier produces syngas from a carbonaceous feedstock such as biomass. The syngas is fed to a syngas burner. A booster burner disposed between the gasifier and the syngas burner increases the temperature of the syngas. The booster burner may be provided with an approximately stoichiometric or sub-stoichiometric amount of oxidant. Operation of the booster burner may be regulated based on the temperature of the syngas. The syngas burner may be used to direct-fire a device requiring a relatively high flame temperature, such as, for example, a lime kiln.

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1. A system in which syngas is supplied as fuel for a burner used to direct-fire a device, the system comprising: a gasifier for producing syngas comprising tars;a syngas burner for receiving syngas from the gasifier by way of a fluid path;a booster burner disposed along the fluid path between the g

1. A system in which syngas is supplied as fuel for a burner used to direct-fire a device, the system comprising: a gasifier for producing syngas comprising tars;a syngas burner for receiving syngas from the gasifier by way of a fluid path;a booster burner disposed along the fluid path between the gasifier and the syngas burner for increasing the temperature of the syngas;one or more temperature sensors for measuring the temperature of the syngas in the fluid path; anda controller configured to regulate the operation of the booster burner based on input from the one or more temperature sensors;wherein the controller is configured to regulate operation of the booster burner to maintain temperatures of syngas being carried along the fluid path above a first threshold temperature that is higher than a temperature at which the tars condense and to prevent the temperatures of syngas being carried along the fluid path from exceeding a second threshold temperature that is lower than a cracking temperature of the tars. 2. A system according to claim 1, wherein the booster burner is positioned so that a flame from the booster burner contacts the syngas directly. 3. A system according to claim 1, wherein the gasifier is a fixed-bed updraft gasifier. 4. A system according to claim 3, wherein the gasifier is connected to receive biomass fuel via a fuel feed assembly. 5. A system according to claim 4, wherein the booster burner is connected to receive fuel comprising natural gas, propane, or oil from a fuel source. 6. A system according to claim 4, wherein the syngas burner is connected to selectively receive both syngas and a fossil fuel. 7. A system according to claim 3, wherein the booster burner is set back within the fluid path so that the stream of syngas travelling in the fluid path does not directly contact the booster burner. 8. A system according to claim 7, wherein the booster burner is positioned so that flame produced by the booster burner intersects with the stream of syngas at a 90° angle. 9. A system according to claim 1, wherein the syngas burner is connected to selectively receive both syngas and a fossil fuel and the controller is connected and configured to control amounts of each of the syngas and fossil fuel based on a temperature within the device direct-fired by the burner. 10. A system according to claim 9 wherein the controller is configured to increase a ratio of fossil fuel to the syngas in response to a decrease of the temperature within the device below a set temperature. 11. A system according to claim 1, wherein the booster burner is configured to use a fuel and an approximately stoichiometric amount of oxidant. 12. A system according to claim 1, wherein the booster burner is configured to use a fuel and slightly less than a stoichiometric amount of oxidant. 13. A system according to claim 1, comprising a lime kiln wherein the syngas burner is a burner of the lime kiln. 14. A system according to claim 1 comprising a power boiler or a dryer wherein the syngas burner is a burner of the power boiler or dryer. 15. A system according to claim 1, wherein the syngas burner is configured to use an approximately stoichiometric amount of oxygen. 16. A system according to claim 1, comprising an oxidizer in fluid communication with the gasifier for oxidizing at least a portion of the syngas. 17. A system according to claim 16, wherein the oxidizer is downstream of the booster burner. 18. A system according to claim 1, wherein the system comprises more than one booster burner. 19. A system according to claim 1, wherein the system comprises two or more gasifiers for producing syngas, each of the gasifiers being located upstream of the booster burner. 20. Apparatus according to claim 1 wherein the controller is configured to regulate operation of the booster burner to maintain the temperatures of syngas being carried along the fluid path to be below 540° C. 21. Apparatus according to claim 1 wherein the controller is configured to regulate operation of the booster burner to maintain the temperatures of syngas being carried along the fluid path to be below 510° C. 22. Apparatus according to claim 21 wherein the controller is configured to regulate operation of the booster burner to maintain the temperatures of syngas being carried along the fluid path to be at least 360° C. 23. Apparatus according to claim 1 comprising ducting directly connecting the gasifier and the syngas burner wherein the fluid path is contained within the ducting. 24. A method for using syngas as fuel in a burner used to direct-fire a device, the method comprising: producing syngas comprising tars in a gasifier;carrying the syngas from the gasifier to a syngas burner along a fluid path;while carrying the syngas along the fluid path, increasing the temperature of the syngas using a booster burner and regulating operation of the booster burner to maintain temperatures of the syngas being carried along the fluid path above a first threshold temperature that is higher than a temperature at which the tars condense and to prevent the temperatures of the syngas being carried along the fluid path from exceeding a second threshold temperature that is lower than a cracking temperature of the tars; andburning the heated syngas in the syngas burner. 25. A method according to claim 24, wherein flame from the booster burner contacts the syngas directly. 26. A method according to claim 24, further comprising monitoring the temperature of the syngas at a point between the gasifier and the syngas burner and adjusting the operation of the booster burner based on the temperature monitored. 27. A method according to claim 26, wherein monitoring the temperature comprises monitoring the temperature at a plurality of points between the gasifier and the syngas burner. 28. A method according to claim 26, comprising turning the booster burner off if the temperature of the syngas at the point between the gasifier and the syngas burner is greater than a predetermined value. 29. A method according to claim 28 comprising feeding biomass into the gasifier, wherein the gasifier generates the syngas from the biomass. 30. A method according to claim 28 wherein the gasifier is a fixed-bed updraft gasifier. 31. A method according to claim 24, further comprising providing a second fuel to the syngas burner in combination with the syngas. 32. A method according to claim 31, further comprising adjusting a ratio of syngas to the second fuel provided to the syngas burner to maintain a flame temperature of the syngas burner of at least about 1800° C. 33. A method according to claim 24, wherein the syngas burner is used to direct-fire a lime kiln. 34. A method according to claim 24, wherein the syngas burner is used to direct-fire a power boiler or dryer. 35. A method according to claim 24, comprising operating the booster burner using a stoichiometric amount of oxygen. 36. A method according to claim 24, further comprising providing at least a portion of the syngas from the gasifier to an oxidizer during start-up of the syngas burner. 37. A method according to claim 24, comprising supplying natural gas as the fuel for the booster burner and operating the booster burner using an approximately stoichiometric amount of oxidant. 38. A method according to claim 24, comprising supplying natural gas as the fuel for the booster burner and operating the booster burner with slightly less than a stoichiometric amount of oxidant. 39. A method according to claim 24, wherein a stream of syngas exiting the gasifier does not impinge directly on the booster burner. 40. A method according to claim 24, comprising maintaining the temperatures of the syngas being carried along the fluid path below 540° C. 41. A method according to claim 24, comprising maintaining the temperatures of the syngas being carried along the fluid path below 510° C. 42. A method according to claim 41, comprising maintaining the temperatures of the syngas being carried along the fluid path to be at least 360° C. 43. A method according to claim 24 comprising delivering the tars to the syngas burner.