Patent ID: 9353321
Filing Date: 2016-05-31
CPC Classification: C01B,C10J,C10K

Claim Text:
1. A method for producing product gas substantially free of tar by gasification of carbonaceous material wherein said method comprises: producing char-ash and tar-laden product gas in a first stage of gasification and transporting said char-ash and tar-laden product gas from the first stage to a second stage of gasification said second stage comprising: substantial separation of char-ash from product gas arising from the second stage of gasification, recycling said char-ash from the second stage by recombining at least a portion of the separated char-ash from the second stage of gasification with the tar-laden product gas and char-ash from the first stage of gasification at an inlet of the second stage of gasification, and providing sufficient time, temperature, and char-ash concentration for tar conversion reactions to take place.