SUNJia-wei,ZHANGYang,JINJian-hua,et al.Impact of Advanced Oxidation Methods on Biodegradability and Biological Inhibition in Wastewater[J].China Water & Wastewater,2025,41(17):120-125.
Impact of Advanced Oxidation Methods on Biodegradability and Biological Inhibition in Wastewater
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第41卷
Number:
第17期
Page:
120-125
Column:
Date of publication:
2025-09-01
- Keywords:
- chemical and pharmaceutical wastewater; biodegradability; biological inhibition; advanced oxidation; electro-peroxone; ozonation
- Abstract:
- Ozonation and electro-peroxone (EP) technologies were employed within a fine chemical industrial park in Ningxia to investigate the biodegradability and biological inhibition of wastewater from three representative chemical and pharmaceutical enterprises that were resistant to conventional biological treatment. All three types of wastewater exhibited certain inhibitory effects on the activity of activated sludge, with the primary toxic constituents being phenolic compounds and organochlorine pesticides (OCPs). Specifically, the wastewater from enterprise A predominantly contained 2-nitrophenol, endrin, o,p’-DDE, etc.. In contrast, the wastewater from enterprise B mainly comprised 2,4-nitrophenol, methoxychlor, chloroform,etc.. The wastewater from enterprise C primarily included 2-nitrophenol, dicofol, dieldrin, etc.. The two advanced oxidation methods significantly enhanced the biodegradability of wastewater and reduced biological inhibition. Following ozonation treatment, the BOD5/COD (B/C) ratio of wastewater samples from enterprises A, B, and C increased from initial values of 0.18, 0.02, and 0.11 to 0.56, 0.29, and 0.36, respectively. Consequently, the biodegradability of the wastewater improved from non-biodegradable to better biodegradable, marginally biodegradable, and biodegradable, respectively, and the corresponding biological inhibition rates all decreased. After EP treatment, the B/C ratios increased to 0.34, 0.16, and 0.32, indicating improved biodegradability classifications as biodegradable, non-biodegradable, and biodegradable, respectively. The biological inhibition rates decreased by 16.3%, 25.9%, and 33.4%, respectively. The efficiency of EP could be significantly reduced by low conductivity and high sulfate concentrations, whereas high chloride concentrations might compromise the effectiveness of ozonation. Furthermore, EP could achieve 90% COD removal within one hour, while the corresponding removal efficiency of ozonation was relatively limited at 64%. Adjusting the concentration of gaseous ozone appropriately could enhance the COD removal efficiency of EP. These findings indicate that advanced oxidation technologies, particularly when integrated with primary treatment methods, are highly effective in treating wastewater generated by the chemical and pharmaceutical industries.
Last Update:
2025-09-01