A METHOD OF CLEANING WATERY VENTILATING AIR CONTAINING LIQUIDS WHICH HAVE BEEN GASIFIED DURING COOLING OR LUBRICATION OF CONVERTING MACHINES, PARTICULARLY ROLLING MILLS, AND AN APPARATUS FOR CARRYING OUT THE METHOD

摘要

A method of cleaning watery ventilating air containing liquids which have been gasified during cooling or lubrication of converting machines, particularly rolling mills, comprises cooling of the ventilating air in one or several stages (I-IV) to temperature below the condensing point of the gasified substances in the ventilating air, so that these substances condensate. In connection with the condensation the larger portion of the condensated cooling or lubricating liquids is separated from the water and reused. The condensated water mixed up with the rests of the condensated cooling and lubricating liquids is returned to the cleaned and dried ventilating air and is caused to be absorbed by the ventilating air. By dividing the cooling operation into two steps, the cooling and lubricating liquids can be caused to condensate in the first stage without condensation of any water and water can be caused to condensate substantially only in the second stage. A portion of the cooling and lubricating liquids condensated in the second stage are separated in a separation tank (24). An apparatus for carrying out the method comprises a plurality of heat exchangers (11-16). The first heat exchangers (11-14) are used for cooling the ventilating air, and the following exchangers (15-16) are used for heating the cleaned and dried ventilating air, so that this air can absorb the condensated water mixed up with the rests of the cooling and lubricating liquids in a moistening device (16a).