Process and plant for at least partial gasification of solid organic feed material

Abstract

A process for at least partial gasification of solid organic feed material, in which, from the feed material, in a low-temperature gasifier by low-temperature carbonization, a tar-containing low-temperature carbonization gas is obtained, and the low-temperature carbonization gas is then reacted in a high-temperature gasifier by partial oxidation and subsequent partial reduction to form a syngas, whereby, in a cooling appliance provided downstream of the high-temperature gasifier, the syngas is cooled in such a manner that alkalis present in the syngas remain in the gaseous phase, and coke particles present in the syngas already no longer possess stickiness, and that in a cyclone appliance provided downstream of the cooling appliance, a coarse fraction of coke particles is separated out from the syngas, wherein a fine fraction of the coke particles passes through the cyclone appliance together with the syngas.

1 . A process for at least partial gasification of solid organic feed material, in which, from the feed material, in a low-temperature gasifier by low-temperature carbonization, a tar-containing low-temperature carbonization gas is obtained, and the low-temperature carbonization gas is then reacted in a high-temperature gasifier by partial oxidation and subsequent partial reduction to form a syngas, characterized in that, in a cooling appliance provided downstream of the high-temperature gasifier, the syngas is cooled to a temperature at which alkalis present in the syngas remain at least in part in the gaseous phase, and coke particles present in the syngas no longer possess stickiness, and that in a cyclone appliance provided downstream of the cooling appliance, a coarse fraction of coke particles is separated out from the syngas, wherein a fine fraction of the coke particles passes through the cyclone appliance together with the syngas. 
     
     
         2 . The process as claimed in  claim 1 , characterized in that the syngas passing through the cyclone appliance is cooled in a cooler provided downstream of the cyclone appliance. 
     
     
         3 . The process as claimed in  claim 1 , characterized in that the coarse fraction of the coke particles separated off in the cyclone appliance is recirculated to the high-temperature gasifier. 
     
     
         4 . The process as claimed in  claim 3 , characterized in that the coarse fraction of the coke particles is transferred, in particular using gravity, into a buffer vessel and then into a stand pipe that is arranged vertically, wherein the height of the stand pipe is selected in such a manner that, in the lowest part of the stand pipe, a pressure that is sufficient for fluidization is providable in order to induce dense-phase conveying, and to ensure the entry into the high-temperature gasifier of the coke provided hereby. 
     
     
         5 . The process as claimed in  claim 4 , characterized in that the diameter of the stand pipe is selected in such a manner that bridge formation of the coke particles is prevented. 
     
     
         6 . The process as claimed in  claim 4 , characterized in that the recirculation of coke via the buffer vessel and the stand pipe is carried out at a temperature which substantially corresponds to the temperature in the cyclone appliance. 
     
     
         7 . A plant which is equipped for carrying out a process for at least partial gasification of solid organic feed material, having a low-temperature gasifier in which a tar-containing low-temperature carbonization gas can be obtained by low-temperature carbonization from a solid organic feed material, and a high-temperature gasifier, in which the low-temperature carbonization as can be reacted by partial oxidation and subsequent partial reduction to form a syngas, wherein, downstream of the high-temperature gasifier, a cooling appliance is provided which cools the syngas leaving the high-temperature gasifier in such a manner that alkalis present in the syngas remain in a gaseous state, wherein coke particles present in the syngas already no longer possess stickiness, and a cyclone appliance provided downstream of the cooling appliance, by means of which cyclone appliance a coarse fraction of coke particles is separated out from the syngas, wherein a fine fraction of the coke particles passes through the cyclone appliance together with the syngas.