Kinetics of wet air oxidation of wastewater from natural fiber web desizing

This work described the application of wet air oxidation (WAO) to the treat ment of desizing wastewater from natural fiber processing. A two-liter auto clave batch reactor was used for the experiments. The range of operating te mperature examined was between 150 and 290 degrees C, and partial pressure of oxygen ranged from 0.375 to 2.25 MPa standardized at 25 degrees C. Varia tions in Chemical Oxygen Demand(COD) and Total Organic Carbon(TOC) were mon itored during each experiment and used to assess the performance of the pro cess. Experimental results showed that WAO can be an efficient method for t he treatment of desizing wastewater. Furthermore, Catalytic Wet Air Oxidati on (CWAO) was applied to reduce the reaction temperature and pressure in WA O process. A higher COD removal ratio was achieved under more mild reaction condition with the aid of CWAO. A mathematical model was also proposed to simulate the WAO process of desizing wastewater, in which three distinct ki netics steps were considered to describe the degradation of starch. The mod el simulations were in well agreement with the experimental data.