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- 2019
臭氧催化氧化对固定床蒸氨脱酚废水去除效果研究Keywords: 臭氧催化氧化,臭氧通气量,臭氧浓度,催化剂投加量,单因素试验,正交试验 ozone catalytic oxidation,ozone ventilation,ozone concentration,catalyst dosage,single factor test,orthogonal test Abstract: 为了获得最佳的臭氧催化氧化工艺参数,采用1 t/h臭氧催化氧化装置利用单因素及正交试验法研究了臭氧通气量、臭氧浓度及催化剂投加量对COD去除效果的影响规律,确定了工艺条件的影响主次顺序及最佳工艺参数。最后在最佳工艺参数下进行连续试验80 h,进一步考察了最佳工艺参数下COD的去除效果。结果表明:3种工艺条件(即臭氧浓度、臭氧通气量、催化剂投加量)对COD去除率均有很大影响。通过单因素试验发现,随着臭氧通气量、臭氧、催化剂投加量增加,在同等条件下COD去除率越大,但相应的处理成本会增加,最终选择臭氧通气量为1.5 m3/h≤臭氧通气量≤2.5 m3/h,臭氧浓度为150 mg/L≤臭氧浓度≤250 mg/L,催化剂投加量选择为20 kg/t≤催化剂投加量≤30 kg/t。通过正交试验发现,3种臭氧氧化条件对COD去除率影响的主次顺序为臭氧浓度>通气量>催化剂投加量,验证了上述单因素试验结果,得到最佳工艺参数为:臭氧通气量2.0 m3/h,臭氧浓度250 mg/L,催化剂投加量30 kg/t。最后采用1 t/h臭氧氧化装置,在最佳工艺参数下对脱酚蒸氨后废水进行连续臭氧氧化试验80 h,COD去除率稳定在43.5%左右,反应后可生化性(B/C)稳定至0.4以上,减轻了后续生化处理的负荷及难度。证明臭氧氧化工艺实际应用效果良好。 In order to obtain the best process parameters of ozone catalytic oxidation,the impact of ozone ventilation,ozone concentrationand catalyst dosage on COD removal was studied by using single factor and orthogonal test method in 1 t/h ozone catalytic oxidation device-and the primary and secondary order of process conditions and the best process parameters were determined.Finally,the best process pa-rameters were tested continuously for 80 hours,and the removal effect of COD under the best process parameters was further investigated. Itis concluded that the three process conditions(i.e. ozone concentration,ozone ventilation capacity and catalyst dosage) have a great influ-ence on COD removal rate.Through single factor experiment,it is found that with the increase of ozone ventilation,ozone and catalyst dos-age,the COD removal rate will increase under the same conditions,but the treatment cost will increase. Considering COD removal rate andozone ventilation cost,the ozone ventilation rate is 1.5 m~3/h≤ozone ventilation rate≤2.5 m~3/h;the ozone concentration is 150 mg/L≤ozone concentration≤250 mg/L;the catalyst dosage is selected as 20 kg/t≤catalyst dosage≤30 kg/t.Through the orthogonal experiment,it is found that the primary and secondary order of the influence of three ozone oxidation conditions on COD removal rate is ozone concen-tration > ventilation > catalyst dosage,which confirms the above single factor test results. The best process parameters are obtained:ozoneventilation 2.0 m~3/h,ozone concentration 250 mg/L,catalyst dosage 30 kg/t.Finally,1 t/h ozonation device was used to carry out continu-ous ozonation test on the wastewater after phenol removal and ammonia evaporation for 80 h under the optimal process parameters and theremoval rate of COD was stable at about 43.5%,and the biodegradability(B/C) after reaction was stable above 0.4,which reduced the loadand difficulty of subsequent biochemical treatment. It is proved that the ozone oxidation process has a good practical application
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