Performance of a low pressure wet air oxidation unit treating steam cracker spent caustic

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:288687

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1. BP Chemicals Ltd., Grangemouth (United Kingdom)

BP Chemicals Limited (BPCL) and Stone and Webster Engineering Limited (SWEL) carried out a joint development program during 1991 and 1992 on spent caustic treatment by Low Pressure Wet Air Oxidation. This included detailed laboratory oxidation trials, plus computer modeling to relate laboratory findings to expected full scale plant results. The development program showed that low pressure oxidation could achieve very high conversions of sulfide to sulfate and low final COD in steam cracker spent caustics, by optimizing process conditions. A full scale Low Pressure WAO unit was commissioned at BP Chemicals Grangemouth in February of 1993, treating spent caustic from steam cracking of both liquid and gas feeds. The unit immediately achieved complete removal of sulfide and, after some optimization of operation conditions, has given consistently high conversion to sulfate. Operation of this unit has therefore considerably improved the combined BP Chemicals aqueous effluent at the Grangemouth site. The pH has dropped, sulfide has been almost completely removed (some is added from sources other than spent caustic) and COD levels are significantly reduced. This paper gives plant results achieved, problems encountered and also discusses the process computer model, updated from the model developed in the laboratory trials.

• OSTI ID: 288687
• Report Number(s): CONF-9404309--
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
CHEMICAL EFFLUENTS
CHEMICAL OXYGEN DEMAND
COMPUTERIZED SIMULATION
DESIGN
PERFORMANCE
SODIUM SULFIDES
SPENT LIQUORS
SULFIDES
THERMAL CRACKING
THIOSULFATES
WASTE WATER
WATER TREATMENT PLANTS
WET OXIDATION PROCESSES