Reuse and recycle solutions in refineries by ozone-based advanced oxidation processes: A statistical approach

Area of Science:

• Environmental Science
• Chemical Engineering
• Water Treatment Technologies

Background:

• Global freshwater scarcity necessitates industrial wastewater reduction and reuse.
• Refinery effluent requires advanced treatment to meet reuse standards after conventional methods.
• Ozone-based oxidation presents a potential solution for tertiary wastewater treatment.

Purpose of the Study:

• To investigate ozone-based treatments for refinery effluent polishing.
• To optimize treatment parameters for effective contaminant removal and water reuse.
• To reduce operational costs through efficient reagent and energy consumption.

Main Methods:

• Screening tests using fractional factorial design to identify significant parameters (ozone feed ratio, H2O2 amount, processing time).
• Box-Behnken response surface methodology for optimizing significant parameters.
• Analysis of final effluent for total organic carbon (TOC) to assess reuse potential.

Main Results:

• Ozone feed ratio, H2O2 amount, and processing time were significant parameters; pH was not.
• Optimized parameters: 0.9 g/h ozone, 47 mg/L H2O2, 60 min processing time.
• Increasing H2O2 to 80 mg/L reduced treatment time to 37.5 min, cutting costs by 37% and achieving TOC < 4 mg/L.

Conclusions:

• Ozone-based advanced oxidation processes are effective for refinery wastewater treatment.
• Parameter optimization significantly reduces treatment time and costs.
• Achieving low TOC levels (< 4 mg/L) enables water reuse, conserving freshwater resources.