Chevron produces anhydrous ammonia for sale. Chevron wanted the flexibility to process some of the ammonia in an existing Sulphur Recovery Unit (SRU). As a result, the sulphur recovery unit had to process a higher than normal level of ammonia. An SO2 recycle stream from the tail gas unit that lowers the reaction furnace temperature further complicated the problem. WorleyParsons was contracted to determined how to debottleneck the unit, whilst also ensuring complete ammonia destruction. We recommended replacement of the existing burner with a new, more efficient burner.
Capability to use oxygen enrichment was also provided. In partnership with Linde, the Reaction Furnaces were retrofitted with burners capable of operating over a range of air-only up to 30% oxygen, with virtually complete destruction of up to 30% ammonia in all cases. To date, more than 30 similar burners designed by WorleyParsons/Linde for 28-100% oxygen have been installed on new and existing units. The unit has successfully processed up to 25% ammonia in the feed with air and 35% ammonia with oxygen.
