Regeneration of waste chemicals from liquid redox processes

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Environmental Progress; (United States)

DOI:https://doi.org/10.1002/ep.670100322· OSTI ID:5544669

Ciriacks, J A; LaFond, J F ^[1]

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1. Engineered Systems International, Appleton, WI (United States)

To avoid the increasingly costly disposal of the waste stream (blowdown) from liquid redox processes used to clean hydrogen sulfide form gases, a reductive burning recovery (RBR) process has been developed. The RBR system concentrates spent chemicals which are primarily sodium thiosulfate and sodium sulfate. The spent chemicals are then thermally destroyed in a reactor. The regenerated salts flow from the bottom of the reactor as a molten smelt containing sodium carbonate, sodium sulfide and sodium vanadate. The molten salt stream is dissolved in water to form a regenerated solution which is fed back into the Stretford process. For the special case of coke oven gas cleaning, elemental sulfur is added to a portion of the regenerated solution in order to clean hydrogen cyanide from the coke gas before the gas is scrubbed with Stretford solution to remove hydrogen sulfide. The sodium thiocyanate product of hydrogen cyanide scrubbing is also thermally destroyed and regenerated by RBR process.

• OSTI ID: 5544669
• Journal Information: Environmental Progress; (United States), Journal Name: Environmental Progress; (United States) Vol. 10:3; ISSN ENVPD; ISSN 0278-4491
• Country of Publication: United States
• Language: English

Related Subjects

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010402* -- Coal
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CHEMICAL REACTIONS
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