Abstract: A mixture of N2 and NO was used as the simulated flue gas, and removal of NO with using the acid urea solution as the sorbent was studied. Investigated the effects of concentration of NO,gas flow rate,concentration of absorbent, pH value of absorption solution,temperature of absorption solution on removal rate. NO removel experiment was conducted in ultrasonic environment. The results showed that the removal rate of NO could reach 86.84 ％ under the optimum condition as followsthe temperature was 50 ℃, the NO initial concentration was3 300 mg／m3, the gas flow rate was 300 mL／min, the urea mass fraction was 10 ％, the pH was 3.00. The ultrasonic played certain role in promoting the absorption process. The experiment indicated that when the ultrasonic power was 5 kW, the removel rate of NO could reach 89.13％.

Key words: nitric oxide, urea, reduction, ultrasonic