化学工学およびプロセス技術ジャーナル
オープンアクセス

概要

Scrubbing of HCl Gas from Synthesis Gas in a Multistage Dual-Flow Sieve Plate Wet Scrubber by Alkaline Solution

Swamy Kurella, Mounika Balla, Pavan Kishan Bhukya and Meikap BC

The synthesis gas leaving from the coal gasification process is having particulate matter and other gaseous pollutants majorly hydrogen sulphide and hydrogen chloride (HCl). Wet scrubbers can simultaneously remove the gaseous pollutants and dust particles from effluent gas streams. Dual-flow sieve plate column wet scrubbers can be used for the removal of acid gases from the exhaust gases. A three stage lab scale dual-flow sieve plate scrubber has been designed, fabricated and installed. Experiments were conducted to remove the HCl from the synthesis gas at different gas-liquid ratios within the gas flow rates (QG) 8.297 × 10-4 Nm3/s, 13.829 × 10-4 Nm3/s and 19.36 × 10-4 Nm3/s, liquid flow rates (QL) 20.649 × 10-6 m3/s, 34.415 × 10-6 m3/s and 48.183 × 10-6 m3/s and at different inlet HCl concentrations (CHCl,i) 100 ppm, 200 ppm and 300 ppm range using sodium hydroxide solution as scrubbing liquid. The maximum percentage removal of HCl (%ηHCl) 93.98% are observed at QG=8.297 × 10-4 Nm3/s, QL= 48.183 × 10-6 m3/s and CHCl,i=300 ppm with 0.005 kmol/m3 NaOH solution. A semi empirical model has been developed to predict the efficiency of the HCl scrubbing using the experimental results and the variables which show the impact on the scrubber performance. Almost 80% of the experimental results are matched well with the predicted values with less than ± 15% deviation.