The raw NF concentrate showed a low BOD5/COD ratio of 0.05, which implied that the organic contents were refractory and difficult to be further biodegraded. After the treatment by ozonation and UV/O3 process, BOD5/COD ratios increased 3.2 and 4.6 times, respectively. The results indicated that biodegradability of NF concentrate was improved after treatment, nevertheless, not satisfactory compared to that reported in previous research [19], which could be due to the difference of water quality, ozone dose, treatment time, etc.
Acute ecotoxicity of raw water and treated samples was tested through evaluating the inhibition of bioluminescence from P. phosphoreum. Results are shown in Fig. 9. For the raw solution spiked with antibiotics, an inhibition ratio of 21% was detected. Both ozonation and UV/O3 process treated samples showed a reduction of toxicity. The remaining toxicity of the treated samples must derive from the degradation products since high removal efficiencies of antibiotics were achieved by both ozonation (above 99%) and UV/O3 treatment (above 99%) after 30 min. The ecotoxicity of NF concentrate from secondary effluent was comparatively prominent (inhibition ratio of 41%). UV/O3 treatment achieved the highest reduction of toxicity of the raw water with inhibition ratio dropped by 58%.
The raw NF concentrate showed a low BOD5/COD ratio of 0.05, which implied that the organic contents were refractory and difficult to be further biodegraded. After the treatment by ozonation and UV/O3 process, BOD5/COD ratios increased 3.2 and 4.6 times, respectively. The results indicated that biodegradability of NF concentrate was improved after treatment, nevertheless, not satisfactory compared to that reported in previous research [19], which could be due to the difference of water quality, ozone dose, treatment time, etc.Acute ecotoxicity of raw water and treated samples was tested through evaluating the inhibition of bioluminescence from P. phosphoreum. Results are shown in Fig. 9. For the raw solution spiked with antibiotics, an inhibition ratio of 21% was detected. Both ozonation and UV/O3 process treated samples showed a reduction of toxicity. The remaining toxicity of the treated samples must derive from the degradation products since high removal efficiencies of antibiotics were achieved by both ozonation (above 99%) and UV/O3 treatment (above 99%) after 30 min. The ecotoxicity of NF concentrate from secondary effluent was comparatively prominent (inhibition ratio of 41%). UV/O3 treatment achieved the highest reduction of toxicity of the raw water with inhibition ratio dropped by 58%.
การแปล กรุณารอสักครู่..