Removal of naphthalene from recirculated wash oil
AssigneeBethlehem Steel Corporation
InventorsKenneth R. Burcaw, Jr., Robert E. Watkins, Jr.
Life of this patent
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Abstract
A bleed stream from the recirculating wash oil in a final cooling system for coke oven gas is centrifugally separated into a waste water stream, a sludge stream and a clean, dry oil stream which is substantially free of solids and has a water content less than 0.5% (wt.). The clean, dry oil stream is heated to less than about 160.degree. C., preferably 125.degree.-135.degree. C., before entering a naphthalene stripper-wash oil still.
Claims9
In a method for the final cooling of coke oven gas using a recirculating water immiscible wash solvent in which the coke oven gas is cooled by contact with the wash solvent in a final cooling tower, a naphthalene enriched wash solvent containing condensed water and solid material emerges from the cooling tower as an effluent and the effluent is split into a recirculated naphthalene enriched wash solvent flow which contains water and solids, and a water flow, the improvement comprising:
- (a) removing a bleed stream of wash solvent from the naphthalene enriched wash solvent flow,
- (b) continually and simultaneously centrifugally separating the wash solvent bleed stream of step (a) into a waste water stream, a sludge stream and a clean, dry wash solvent stream which is substantially free of solids and has a water content less than 0.5% (wt.),
- (c) heating the clean, dry wash solvent stream to a temperature of less than about 160.degree. C., and
- (d) stripping the naphthalene from the clean, dry wash solvent stream with steam to yield a stripped wash solvent.
Dependencies are inferred from the claim text.