Method and Device for Optimised Fluidised Bed Gasification

Abstract

Method and device for the gasification of feed to form synthesis gas, with a gasifier comprising at least one pulse heater, and with a fluidised bed in the gasifier, in which the fluidised bed is kept in motion in a controlled manner by means of a feed nozzle introducing steam and/or synthesis gas and/or fine dust into the reactor such that the reaction zone is increased.

1 . Method for the gasification of feed to form synthesis gas, with a gasifier comprising at least one pulse heater, and with a fluidised bed in the gasifier, in which the fluidised bed is kept in motion in a controlled manner by means of a feed nozzle introducing steam or synthesis gas or fine dust into the reactor such that the reaction zone is increased. 
   
   
       2 . The method according to  claim 1 , in which the feed nozzle is arranged below the fluidised bed. 
   
   
       3 . The method according to  claim 2 , in which the motion of the fluidised bed is controlled in a specific manner by means of jet nozzles. 
   
   
       4 . The method according to  claim 3 , in which the macroflow to be obtained for the fluidised bed is supposed to be similar to the air-lift pump principle, thereby resulting in an increase in the reaction zone for flash pyrolysis and an increase in the retention time of the primary pyrolysis coke in order to increase heat and mass transfer. 
   
   
       5 . The method according to  claim 1 , in which the circulating fluidised bed is controlled in such a manner that the voluminous biomass introduced into the lower part of the steam converter is accelerated so that the reaction section and therefore the effective reactor volume for the primary conversion for this reaction are increased preferably by the factor of 2 to 4. 
   
   
       6 . The method according to  claim 1 , in which the fine dust is conveyed into the dense fluidised bed with the aid of the driving jet principle, the reaction thus being improved as a result of an increase in the retention time and intensive mixing of the dust with the hot bed material. 
   
   
       7 . Method for the gasification of feed to form synthesis gas, with a gasifier comprising at least one pulse heater, and with a fluidised bed in the gasifier, comprising:
 returning parts of the synthesis into the fluidised bed.   
   
   
       8 . The method according to  claim 7 , in which the synthesis gas is fed to the gasifier together with steam. 
   
   
       9 . The method according to  claim 8 , in which at least one steam jet conveyor is used to introduce the synthesis gas into the steam. 
   
   
       10 . The method according to  claim 9 , in which the use of one or more steam jet conveyors is controlled in such a manner that the quantity of steam required for fluidisation is minimised, part of the steam being replaced by recycled synthesis gas and/or the introduction of heat being increased by material heat conduction from the region of the pulse heaters. 
   
   
       11 . The method according to  claim 7 , in which the synthesis gas is recycled in an only partially purified state. 
   
   
       12 . A device for the gasification of feed to form synthesis gas, with a gasifier comprising at least one pulse heater, and with a fluidised bed in the gasifier, comprising:
 a feed nozzle introducing steam or synthesis gas or fine dust into the reactor and controlled by means in such a manner that the fluidised bed is kept in motion so that the reaction zone is increased.   
   
   
       13 . The device according to  claim 12 , in which the feed nozzle is arranged below the fluidised bed. 
   
   
       14 . The device according to  claim 13 , in which the feed nozzles are jet nozzles which control the motion of the fluidised bed in a specific manner. 
   
   
       15 . The device according to  claim 14 , in which the control means are designed in such a manner that the macroflow to be obtained for the fluidised bed is similar to the air-lift pump principle, thereby resulting in an increase in the reaction zone for flash pyrolysis and an increase in the retention time of the primary pyrolysis coke in order to increase heat and mass transfer. 
   
   
       16 . The device according to  claim 12 , in which the control unit for the feed nozzles is designed in such a manner that the circulating fluidised bed is controlled in such a manner that the voluminous biomass introduced into the lower part of the steam converter is accelerated so that the reaction section and therefore the effective reactor volume for the primary conversion for this reaction are increased preferably by the factor of 2 to 4. 
   
   
       17 . The device according to  claim 12 , in which the feed nozzles inject fine dust from the synthesis gas purification process into the dense fluidised bed, the reaction thus being improved as a result of an increase in the retention time and intensive mixing of the dust with the hot bed material. 
   
   
       18 . A device for the gasification of feed to form synthesis gas, with a gasifier comprising at least one pulse heater, and with a fluidised bed in the gasifier, in which means are provided for returning parts of the synthesis gas to the fluidised bed. 
   
   
       19 . The device according to  claim 18 , in which means are provided for feeding the synthesis gas to the gasifier together with the steam. 
   
   
       20 . The device according to  claim 19 , in which at least one steam jet conveyor is provided to introduce the synthesis gas into the steam. 
   
   
       21 . The device according to  claim 20 , in which means are provided to control the use of one or more steam jet conveyors in such a manner that the quantity of steam required for fluidisation is minimised, part of the steam being replaced by recycled synthesis gas and/or the introduction of heat being increased by material heat conduction from the region of the pulse heaters. 
   
   
       22 . The device according to  claim 18 , in which means are provided for recycling the synthesis gas in an only partially purified state.