Gas purification device

A gas purification device for purifying a first gas containing ammonia and hydrogen sulfide, comprising:

• an ammonia removal part configured to remove a part of ammonia contained in the first gas from the first gas;
• a first off-gas recovery part configured to recover a first off-gas containing ammonia removed by the ammonia removal part;
• a hydrogen sulfide/ammonia removal part configured to remove hydrogen sulfide and ammonia from a second gas produced by removing the part of ammonia by the ammonia removal part;
• a second off-gas recovery part configured to recover a second off-gas containing hydrogen sulfide and ammonia removed by the hydrogen sulfide/ammonia removal part;
• and
• a combustion part configured to combust the first off-gas and the second off-gas,
• wherein the combustion part includes:
• a first combustion chamber in which combustion is performed in a reducing atmosphere;
• a second combustion chamber in which combustion is performed in a reducing atmosphere downstream of the first combustion chamber;
• and
• a third combustion chamber in which combustion is performed in an oxidizing atmosphere downstream of the second combustion chamber, and
• wherein the gas purification is configured such that the first off-gas flows into the first combustion chamber, and the second off-gas flows into the third combustion chamber.