Method of coke-oven by-product recovery

Claim 1

IN A PROCESS FOR THE RECOVERY OF BY-PRODUCTS FROM HOT COKE OVEN GASES, THE STEPS OF CONTACTING SAID GASES WITH AN AQUEOUS LIQUOR TO REMOVE TAR THEREFROM, CONTACTING THE GASES WITH A SUBSTANTIALLY NAPHTHALENE-FREE CREOSOTE ABSORBER OIL HAVING AN INITIAL POINT ABOVE ABOUT 225* C. AND AN END POINT NOT HIGHER THAN ABOUT 335* C. TO REMOVE NAPHTHALENE THEREFROM WITH CONSEQUENT ENRICHMENT OF SAID ABSORBER OIL, CONTACTING THE GASES WITH A SUBSTANTIALLY NAPHTHALENE AND LIGHT OIL FREE ABSORBER OIL HAVING AN INITIAL POINT ABOVE ABOUT 225* C. AND AN END POINT NOT HIGHER THAN ABOUT 335* C. TO REMOVE LIGHT OILS THEREFROM, AND CONTINUOUSLY DISTILLING AT LEAST A PORTION OF THE TAR IN ADMIXTURE WITH AT LEAST A PORTION OF THE NAPHTHALENE RICH ABSORBER OIL SEPARATED FROM THE GASES, SAID DISTILLATION COMPRISING A FIRST STAGE WHEREIN PITCH IS CONTINUOUSLY REMOVED FROM THE MIXTURE AND A SECOND STAGE WHEREIN THE PITCHFREE MIXTURE IS CONTINUOUSLY SEPARATED INTO A CREOSOTE OIL HAVING AN END POINT BELOW ABOUT 335* C. AND A LOWER BOILING PORTION, SAID CREOSOTE OIL BEING CONTINUOUSLY RECYCLED FOR USE AS THE ABSORBER OIL IN REMOVING NAPHTHALENE AND LIGHT OILS FROM FRESH COKE OVEN GAS.