Study of pressurized absorption of nitrogen oxides in water

To find a high efficient method to control the nitrogen oxides pollution, pressurized absorption was studied with simulation waste gas. The results show that at lower pressures (0 - 0.4)MPa, the nitrogen oxides absorption efficiency in water decreases with increasing the inlet concentration of nitrogen oxides, but at higher pressure(0. 4 - 0.8MPa) it increases with increasing the inlet concentration. The absorption efficiency increases with increasing the operation pressure, the efficiency at 0.8MPa is six times more than that of at atmospheric pressure, but the increase become less with the pressure higher than 0.6MPa. So the pressurized absorption is a very good method to control the nitrogen oxides emission, the optimum pressure is 0. 4 - 0.6MPa. The operating cost of pressurizing gas can be compensated by the nitric acid recovery.