Efficient degradation of evaporative condensing liquid of shale gas wastewater using O3/UV process
| Autor: | Liu Min, Lu Tao, Chen Ying, Jiang Wenju |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
021110 strategic
defence & security studies Environmental Engineering Ozone Central composite design General Chemical Engineering Chemical oxygen demand 0211 other engineering and technologies 02 engineering and technology 010501 environmental sciences medicine.disease_cause 01 natural sciences chemistry.chemical_compound chemistry Wastewater medicine Environmental Chemistry Hydroxyl radical Response surface methodology Safety Risk Reliability and Quality Hydrogen peroxide Ultraviolet 0105 earth and related environmental sciences Nuclear chemistry |
| Zdroj: | Process Safety and Environmental Protection. 121:175-183 |
| ISSN: | 0957-5820 |
| DOI: | 10.1016/j.psep.2018.10.011 |
| Popis: | In this study, a batch experiment was used to investigate the degradation of real evaporative condensing liquid of shale gas wastewater (ECLSGW). We showed that compared to the O3, ultraviolet (UV), UV/TiO2, and O3/UV/TiO2 processes, the O3/UV process has better performance in removing the chemical oxygen demand (COD) and total organic carbon (TOC) of ECLSGW under the same conditions. The effects of initial pH (3–12), ozone flow rate (0.1–0.5 L/min), UV power (15–50 W), and reaction time (0–60 min) on the degradation of ECLSGW via the O3/UV process were investigated using a single-factor experiment. Moreover, the optimal experimental conditions were obtained using a quadratic polynomial prediction model (RAdj2=0.9961) that was obtained from the central composite design (CCD) of the response surface methodology (RSM). Under optimal experimental conditions, the COD and TOC removal efficiency reached 93.12 and 95.5%, respectively. In addition, gas chromatography–mass spectrometry analysis showed that the O3/UV process could nearly completely mineralize organic pollutants in the ECLSGW. Hydrogen peroxide (H2O2) and hydroxyl radical ( OH) were identified by manganese dioxide (MnO2) and tert-butanol (TBA). The mechanism research showed that OH plays an important role in the degradation of organic pollutants. In summary, the O3/UV process is an effective method to degrade ECLSGW. |
| Databáze: | OpenAIRE |
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