Pilot-scale microaerobic hydrolysis-acidification and anoxic-oxic processes for the treatment of petrochemical wastewater

The periodic variation of operation states in triple ditch (BIO-DENITRO process) was investigated in a pilot-scale and a full-scale triple ditch treating raw wastewater containing 70% petrochemical wastewater and 30% domestic wastewater. Mathematical models describing the periodic variation of activated sludge concentrations in each ditch were proposed based on theoretical analysis and were verified in the pilot-scale and full-scale triple ditches respectively. The existence of optimal cycle time and time arrangement of periodic operation programs were demonstrated and discussed according to the mathematical models and the experimental results of the pilot-scale triple ditch operated in four different stages. Four rulers determining the duration and operation programs are suggested.

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Efficient high strength petrochemical wastewater treatment in a hybrid vertical anaerobic biofilm (HyVAB) reactor: a pilot study

Water Practice & Technology ◽

10.2166/wpt.2017.051 ◽

2017 ◽

Vol 12 (3) ◽

pp. 501-513 ◽

Cited By ~ 5

Author(s):

Shuai. Wang ◽

Nirmal. Ghimire ◽

Gang. Xin ◽

Eshetu. Janka ◽

Rune. Bakke

Keyword(s):

Wastewater Treatment ◽

Hydraulic Retention Time ◽

Loading Rate ◽

High Strength ◽

Pilot Scale ◽

Organic Loading Rate ◽

Anaerobic Sludge ◽

Organic Loading ◽

Petrochemical Wastewater ◽

Step Flow

Performance of a pilot scale Hybrid Vertical Anaerobic Biofilm (HyVAB) reactor treating petrochemical refinery wastewater is presented here. The reactor is an integration of a bottom anaerobic sludge bed and a top aerobic biofilm stage and was operated continuously for 92 days at 21 ± 2 °C. Wastewater was fed continuously to the reactor with step flow increases reducing hydraulic retention time from 55 to 12 hours, increasing organic loading rate from 3 to 33 kg-COD/m3·d. The HyVAB removed on average 91% and 86% of the soluble and total feed COD, respectively, at steady state and loads up to 23 kg-COD/m3·d, of which 98% of the soluble COD removal occurred in the anaerobic stage. Methane yield ranged from 0.29 to 0.51 L/g-COD removed, including conversion of settled aerobic sludge to methane. Sludge production was low (0.04 kg-VSS/kg-COD removed) and biogas methane content high (84 ± 2%). The results demonstrated that HyVAB is an efficient, low footprint alternative for high strength wastewater treatment.

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Pilot-scale in situ treatment of landfill leachate using combined coagulation–flocculation, hydrolysis acidification, SBR and electro-Fenton oxidation

Environmental Technology ◽

10.1080/09593330.2017.1329347 ◽

2017 ◽

Vol 40 (17) ◽

pp. 2191-2200 ◽

Cited By ~ 5

Author(s):

Jun Zhang ◽

Xiaogang Wu ◽

Di Qiu ◽

Jianguo Mao ◽

Hui Zhang

Keyword(s):

Landfill Leachate ◽

Pilot Scale ◽

Fenton Oxidation ◽

Hydrolysis Acidification

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Enhanced Treatment of Pharmaceutical Wastewater by an Improved A2/O Process with Ozone Mixed Municipal Wastewater

Water ◽

10.3390/w12102771 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2771

Author(s):

Jian Wang ◽

Cong Du ◽

Feng Qian ◽

Yonghui Song ◽

Liancheng Xiang

Keyword(s):

Municipal Wastewater ◽

Oxygen Demand ◽

Domestic Wastewater ◽

Pilot Scale ◽

Cod Removal ◽

Microbial Community Analysis ◽

Ozone Treatment ◽

Pharmaceutical Wastewater ◽

Nitrogen And Phosphorus ◽

Hydrolysis Acidification

A pilot-scale experiment is carried out for treating mixed wastewater containing pharmaceutical wastewater (PW) and domestic wastewater (DW), by a process that is a combination of hydrolysis acidification-ozone-modified anaerobic–anoxic–aerobic-ozone (A2/O) (pre-ozone) or hydrolysis acidification-modified A2/O-ozone (post-ozone). The effects of different mixing ratios of PW and DW and pre-ozone treatment or post-ozone treatment on the removal of nitrogen and phosphorus and chemical oxygen demand (COD) are compared and studied. The optimal ratio of PW in mixing wastewater is 30%, which has the optimal COD removal efficiency and minimum biotoxicity to biological treatment. The pre-ozone treatment shows more advantages in removing nitrogen and phosphate but the post-ozone treatment shows more advantages in COD removal. Analysis of dissolved organic matter (DOM) demonstrates that post-ozone treatment has a more significant effect on the removal of fulvic acid and humic acid than the effect from the pre-ozone treatment, so the COD removal is better. Overall DOM degradation efficiency by post-ozone treatment is 55%, which is much higher than the pre-ozone treatment efficiency of 38%. Microbial community analysis reveals that the genus Thauera and the genus Parasegetibacter take great responsibility for the degradation of phenolics in this process. All the results show that the post-ozone treatment is more efficient for the mixed wastewater treatment in refractory organics removal.

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