Improving the efficiency of cleaning gas emissions from foundry

The work is devoted to the topical problem of increasing the efficiency of cleaning process of gases in packed-type scrubbers in order to reduce emissions of harmful substances and solid impurities into the atmosphere and improve the technical and economic indicators of wet gas cleaning systems. For this, a triangular cross-cut packing has been developed. Due to the size of the holes and their specific shape, the triangular packing provides longer contact of the packaging with water, which reduces water consumption. The packing is made of alloy steel AISI 316, so it can be used even in the most aggressive environment. In the work, the efficiency of cleaning with a scrubber with this packing is experimentally determined. The tests were performed at an ambient temperature of 23 °C. Several measurements were made for each type of packing, in a typical scrubber design. To conduct these industrial tests, a thermohygrometer-carbon dioxide gas analyzerAZ-7797 was used with high-precision NDIR (infrared) sensor, automatic background calibration (W/ABC), and compensation for deviations during long-term operation. The concentration measurement range is 0-9999 ppm with an error of ± 5 %. The gases were cooled in two stages. At first, they were cooled with ammonia water from 750 to 80 °C. Then they were fed to a primary gas refrigerator (basic type) of direct action, where its temperature were falled to 15 °C. Carbon dioxide concentration was measured after the first stage of cooling, after the final cooling, and after the cleaning process. The comparison is carried out with the most effective types of packing for wet gas cleaning today – chordal wood and Raschig rings. It is shown that the developed triangular packing with cross-shaped notches during the purification of coke oven gas from carbon dioxide improves the purification by 25 % in comparison with the wooden chord one, and by 15 % - with Raschig rings. This allows us to recommend it for widespread implementation.