| dc.description.abstract | The KOH concentration in strong alkaline dyeing wastewater from the process of the recovery of color glass filter plate is about 2.7N. The strong alkaline dyeing wastewater should be reduced to a suitable pH range of 9~12, so that it can be treated by other process. Electrodialysis is most suitable to reduce the basicity of the wastewater and simultaneously recover the KOH.
And this research is strong alkaline dyeing wastewater from the process of the recovery of color glass filter plate treatment by catalytic Wet Air Oxidation (COD 160000-180000 ppm), pH > 13, conductivity is 57 mS/cm , this research carries on the choice of the catalyst at first, compare V2O5, Ru/C and MnO2 , after 120 minutes, can all make pH drop effectively , and the COD removal is respectively V2O5: 34.2% , MnO2: 37.7% , Ru/C : 36.7%, the result to show MnO2 and Ru/C have better oxidation ability, but the price relatively has Ru/C on the high side, considering the factor of the cost , so choose MnO2 for this wet type of catalysis.
As to adding the system of the catalyst , carry on the comparison of conductivity , pH and COD removal, and change the parameter as reflecting temperature, oxygen pressure, stirring speed , amount of catalyst, in order to seek the optimum condition. stirring speed, there is better getting COD removal in above 400 rpm , so choose 500 rpm; And temperature drops more obvious in pH, but react and lower to 1.77 to its pH value after 120 minutes under 220℃, so choose 200℃; The pressure is increase with Po2, COD removal is also increase relatively, so choose Po2, 0 =350 psig, and Pt = 600 psig; the amount of Catalyst shows that 0.032 g (3% ) and 0.048 g (4% ) have better COD removal, so choose the amount of catalyst of 0.048 g MnO2.
With reflect the increase of time, the quantity of the carbon dioxide increases too, and reduce the oxygen enter the reactor , in order to confirm the carbon dioxide is the influence factor , and then change the concentration of the potassium hydroxide, whether absorb the carbon dioxide because the increase the concentration of potassium hydroxide, enable oxygen to enter and participate in reacting smoothly, reaction: CO2 + KOH K2CO3 . There is better COD removal for 0.27 M and 0.6 M in KOH concentration, so choose 0.27 M.
Synthesize the above result finally, it is determined that the optimum operation parameters (stirring speed 500 rpm , KOH concentration 0.27 M , temperature 200℃, Po2 , 0 = 350 psig ,the amonut of catalysis is 0.048 g (4% )),but with reflect the increase of time, the quantity of the carbon dioxide increases too, makes Po2 drop and difficult to enter reactor, so cooperate with many steps to operate to reject the carbon dioxide, and with the optimum conditions, the many steps, COD removal up to 92.4% already , can make strong alkaline dyeing wastewater to decompose. | en_US |