催化湿式氧化预处理造纸黑液

Pretreatment of Black Liquor by Catalytic Wet Air Oxidation

采用连续式固定床反应器,利用自制稀土类复合金属氧化物催化剂对草浆造纸黑液进行了催化湿式氧化(CWAO)预处理研究。通过正交实验确定了最佳工艺条件为:进水COD 40 800 mg/L,空速0.8 h-1,反应温度260℃,反应压力6.5 MPa。在此最佳条件下进行实验,COD去除率达90%。经CWAO工艺处理后,草浆造纸黑液的可生化性显著提高,BOD5/COD由0.11提高至0.62。在1 000 h CWAO连续实验中,自制稀土类复合金属氧化物催化剂显示出较高催化活性和较好的稳定性。

The black liquor from straw pulp paper-making was pretreated by catalytic wet air oxidation （CWAO） in the continuous fixed bed reactor with self-made rare earth oxide catalyst. The optimum process conditions determined by the orthogonal tests are as follows： influent COD 40 800 mg/L, space velocity 0.8 h^-1, reaction temperature 260℃, reaction pressure 6.5 MPa. Under these conditions, the COD removal rate is 90%. The biodegradability of the treated black liquor is significantly improved with BOD/COD increased from 0.11 to 0.62. During 1 000 h of the CWAO continuous experiment, the catalytic activity and stability of the self-made rare earth oxide catalyst are good.