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Improved Ozonation Efficiency for Polymerization Mother Liquid from Polyvinyl Chloride Production Using Tandem
Zhiyong Yang1,2,3, Penglei Wang1,2, Yagang Zhang1,2,3,4
1Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011, China.
Molecules (Basel, Switzerland)
|December 11, 2019
Summary
Ozone reactors effectively degrade PVC polymerization mother liquid wastewater. Using more reactors in series significantly improves ozone efficiency for chemical oxygen demand removal.
Area of Science:
- Environmental Chemistry
- Chemical Engineering
Background:
- Polymerization mother liquid (PML) is a major wastewater source in the chlor-alkali industry, particularly from PVC production.
- Effective treatment methods are needed to reduce the environmental impact of PML.
Purpose of the Study:
- To investigate the ozonation efficiency for degrading PML using tandem ozone reactors.
- To determine the effects of ozone concentration, number of reactors, and reaction time on chemical oxygen demand (COD) removal.
Main Methods:
- Ozonation of PML using three and five ozone reactors in series.
- Systematic variation of ozone concentration and reaction time.
- Monitoring of COD removal to assess degradation efficiency.
Main Results:
- COD removal increased with ozone concentration up to 80.6 mg·L⁻¹, reaching 66.4%.
- Higher ozone concentrations and longer reaction times initially increased degradation rates, which then decreased.
- Ozone utilization efficiency significantly improved with more reactors in series, with five reactors being three times more efficient than three.
Conclusions:
- Tandem ozonation is a promising technology for treating PML wastewater.
- Increasing the number of reactors in series enhances ozone utilization efficiency.
- Optimizing ozone concentration and reaction time is crucial for effective PML degradation.
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