| 摘要: | 彩色濾光片所產生之甚高濃度有機廢水之催化溼室氧化處理中，氫氧化鉀濃度大約1.7 N，須降至適當的pH = 9~12 才能做後續處理。而電透析是為一種有效降低該廢水氫氧化鉀濃度、並且回收氫氧化鉀的方法。而後續處理就是濕式催化氧化。 而本研究是以催化濕式氧化法(Catalytic Wet Air Oxidation ，CWAO)處理彩色濾光片玻璃基板再生製程強鹼染料廢水，(COD約160000-180000 ppm)，pH值> 14，導電度約87 mS/cm，本研究首先進行催化劑的選擇，比較氧化銅 ( CuO )、氧化亞銅 (Cu2O)、Ru on Carbon、二氧化錳 ( MnO2 )、四氧化三鈷 ( Co3O4 )、以及氧化鋅 (ZnO)等等催化劑對於此反應的催化氧化能力，在溫度120 oC，反應至120分鐘後，部份的催化劑能使COD明顯的下降，而COD去除率較佳的分別為Cu2O : 29.7 %、CuO : 21 %、Co3O4 : 19 %，其結果顯示Cu2O較佳，故選擇Cu2O為此處理程序的催化劑。 對於有無添加催化劑的系統，進行導電度、pH值及COD去除率之比較，並改變操作參數，如反應溫度、氧氣壓力、攪拌速率、催化劑含量等可控因素對催化濕式氧化系統之影響，以尋求最適處理條件。攪拌速率方面，在500 rpm以上有較佳的COD去除率，故選擇600 rpm；而溫度方面120 ℃以上其COD去除率較佳；壓力方面隨著Po2,0(初始通入氧氣量)的增加，COD去除率也相對增加，所以選擇Po2,0 = 500 psig，而反應總壓為530 psig；催化劑量方面顯示1.2 g (15 g/L)較佳的COD除去率。 最後綜合以上結果，決定出最適化的操作參數進行反應(攪拌速率600 rpm、溫度120 ℃、Po2,0 = 500 psig、催化劑量1.2 g (15 g/L)，但反應時間的增加Pco2的量已佔總壓的大部份，使Po2量下降且氧氣不易進入，所以配合多段操作的方式去除產生的二氧化碳，使氧氣能順利進入並參與反應，而本研究的成果在以上最佳操作條件下，以多段操作洩除Pco2方式，配合後半段變溫的操作，在反應330分鐘後COD去除率已達91.69 %，已能使高強度的廢水被氧化分解，期望能更進一步深度處理而達到回收再利用的標準。 The KOH concentration of the very high organics contaminated wastewater from the process of the recovery of color glass filter plate is about 1.7N. The very high organics contaminated wastewater should be reduced to a suitable pH range of 9 to12, so that it can be treated by other process. Electrodialysis is a suitable process to reduce the basicity of the wastewater and simultaneously recover the KOH. And the process after electrodialysis is wet air oxidation. This research is the very high organics contaminated wastewater from the process of the recovery of color glass filter plate treatment by catalytic Wet Air Oxidation (COD 160000-180000 ppm), pH > 14, conductivity is 87 mS/cm . At the first, this research carries on the choice of the catalyst, compare CuO, Cu2O and Ru on Carbon , MnO2 , Co3O4, ZnO etc. to react for 120 minutes at 120 oC, some of them could make COD removal % increase effectively , and the more effective catalysts in COD removal % are respectively Cu2O : 29.7 % , CuO : 21 % , Co3O4 : 19 %, the result to show Cu2O has better oxidation ability, so choose Cu2O as catalysis for process. And then, comparing the no catalyst system and different kind of catalysts system, carry on the comparison of conductivity , pH and COD removal %, and change the parameter as react 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 500 rpm , so choose 600 rpm; And temperature is more effective above 120 ℃; The pressure is increase with Po2, COD removal % is also increase relatively, so choose Po2 =500 psig, and Pt = 530 psig; the amount of Catalyst shows that 1.2 g (15 g/L) has better COD removal %. Synthesize the above result finally, it is determined that the optimum operation parameters (stirring speed 600 rpm , temperature 120 ℃, Po2 = 500 psig ,the amount of catalysis is 1.2 g (15 g/L),but with the increasing of time, the quantity of the carbon dioxide increases too. It makes Po2 drop and difficult to enter reactor, so we cooperate with many steps and changing temperature to 150 oC upper 150 min to operate to reject the carbon dioxide and increase COD removal %. After operating the many steps in the optimum conditions, the COD removal could be up to 91.69 % already , can make the very high organics contaminated wastewater to decompose. |
