GB920780A - Improvements in or relating to coke oven gas naphthalene absorbing final cooler - Google Patents

Abstract

In the final water cooler of a gas purification system interposed between a saturator in which ammonia is removed from the gas and a scrubber in which benzol is washed out with a wash oil, the gas entering at 24 is sprayed with water supplied from a cooling device (not shown) and in the lower section of the cooler the water is extracted with hot tar to remove naphthalene therefrom before the water is passed back to the water cooler; naphthalene containing water collects above a funnel 33 with a leg 32 which delivers it on to the bottom tray of a series of spaced horizontal trays 35, the water level above the funnel being controlled to give the water sufficient time to lose most of its entrained gas bubbles before discharge on to the trays 35; tar is supplied from a line 50 through line 51 and intermittently or continuously through one or more of lines 52 and contact with the naphthalene containing water is made on the trays 35, each tray being provided with a tar drain 42 leading into a sump at the bottom of the cooler and from where tar is withdrawn under control of a level controlling device 59; the naphthalene-free water rises to the water outlet 43 over a series of inclined trays 36 which prevent foam and entrained gas bubbles and hence tar being carried out with the water to the water cooler, the spaces under the inclined trays being provided with vent pipes 40 leading up to the gas space in the upper part of the cooler. As shown a conical baffle 271 and a ring element 29 are arranged above the <PICT:0920780/III/1> level of the water in the funnel 33 but these may be dispensed with if the space in the upper part of the cooler is provided with a packing. The trays 36 may be horizontal if provided with downwardly extending lips at their free edges.