Patent ID: 9505999
Filing Date: 2016-11-29
CPC Classification: C10J,C10K,Y02E

Claim Text:
1. A method to reduce the formation of effluent water in coal gasification and syngas pretreatment processes comprising the following steps: transferring a high temperature syngas from a gasifier to a cooler for initial cooling to produce a first cooled syngas, transferring the first cooled syngas to a dust remover to produce a dedusted syngas, transferring the dedusted syngas to a concentrator to produce a concentrated syngas, transferring the concentrated syngas from the concentrator to a scrubber to remove impurities to produce a scrubbed syngas, heating the scrubbed syngas to a superheated syngas in a heat exchanger, transferring the impurities to washing water to produce a salt-containing water, transferring said salt-containing water from the scrubber to the concentrator, a concentration step within the concentrator comprising: contacting the salt-containing water with the dedusted syngas, evaporating a portion of the salt-containing water by the heat from the dedusted syngas to produce a high salt concentration residual water, transferring the high salt concentration residual water out of the concentrator, and mixing the vapor generated by evaporation with said dedusted syngas; transferring the superheated syngas out from the heat exchanger to a catalytic shift reactor for water-gas shift reaction, transferring the superheated syngas from the catalytic shift reactor to produce a second cooled syngas in a plurality of cooling stages: in a first cooling stage producing a first condensate water and transferring this to the scrubber as the washing water, in a second cooling stage producing a second condensate water and returning the second condensate water to the second cooling stage as cooling water; transferring the second cooled syngas to an ammonia washing tower and washing with demineralized water to produce additional washing water, transferring the additional washing water to the scrubber for syngas scrubbing, transferring the syngas from the ammonia washing tower to a purification system.