A system includes a purification unit configured to process a vapor stream including sulfur dioxide. The purification unit includes an inlet configured to allow the vapor stream to enter the purification unit. The purification unit includes a steam coil configured to circulate steam and provide a source of heat. The purification unit includes a packed bed. The purification unit includes a tray configured to accumulate sulfur. The purification unit includes an absorber section configured to remove at least a portion of the sulfur dioxide from the vapor stream. The purification unit includes an outlet configured to allow an effluent with a lower sulfur dioxide content than the vapor stream to exit the purification unit. The system includes a sulfur tank including a vent line in fluid communication with the inlet. The vent line is configured to allow vapor to flow from the sulfur tank to the purification unit.