Purge system for regenerative thermal oxidizer

A method for purging a regenerative thermal oxidizer, comprising the steps of:

• a) providing at least one purge recovery tank, a stack, a stack bypass, a stack valve in the stack, and a stack bypass valve in the stack bypass, wherein the at least one purge recovery tank is in fluid communication with two heat exchange beds, the stack, the stack bypass and a main waste gas feed, and wherein the stack is in fluid communication with the stack bypass and the at least one heat exchange bed;
• b) reversing flow through the heat exchange beds;
• c) closing the stack valve;
• d) opening the stack bypass valve;
• e) forcing untreated waste gases in a first heat exchange bed into the at least one purge recovery tank and substantially simultaneously forcing the contents of the at least one purge recovery tank out of the stack through the stack bypass;
• f) closing the stack bypass valve such that the untreated waste gases received by the at least one purge recovery tank remain in the at least one purge recovery tank;
• g) opening the stack valve;
• h) recycling the untreated waste gases received in the at least one purge recovery tank to the main waste gas feed;
• and
• i) drawing treated waste gases from the first heat exchange bed into the at least one purge recovery tank.

A purge system for a regenerative thermal oxidizer, comprising:

• a purge recovery tank including an inlet, a first outlet and a second outlet, the inlet to the purge recovery tank connected to two heat exchange beds, the second outlet of the purge recovery tank connected to a main waste gas feed, via a recycle duct;
• a stack connected to the inlet for the purge recovery tank and to the heat exchange beds;
• a stack bypass connecting the stack to the first outlet of the purge recovery tank;
• a stack valve located in the stack between the inlet to the purge recovery tank and a junction of the stack and the stack bypass;
• a stack bypass valve located in the stack bypass;
• and
• a purge recycle control valve located in the recycle duct between the second outlet of the purge recovery tank and the main waste gas feed.