Sulphur Oxyanion Oxidation Using Sparged Oxidant Microbubbles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Fenton oxidation processes are inefficient and costly due to radical scavenging, excessive oxidant consumption, sludge generation, and strict pH and reagent dosage requirements, making them unsuitable for treating sulphur species in alkaline or neutral conditions, and they suffer from poor mixing and short-lived radicals.
Innovation Solution
A method using gas-liquid sparger technology with vaporized hydrogen peroxide to generate long-lived reactive radicals in alkaline, neutral, or acidic conditions, eliminating the need for catalysts and precise pH control, and enhancing oxidation efficiency through uniform distribution of microbubbles and nano droplets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If Fenton oxidation process is used to oxidize sulphur species, then oxidation of sulphur species can be achieved, but excessive oxidant consumption occurs due to radical scavenging and self-decomposition
Solution Approach 1:
The invention changes the pH parameter from acidic (pH 3) to alkaline conditions (pH 9-11), which fundamentally alters the reaction mechanism. In alkaline conditions, hydroxyl radicals are less prone to scavenging by ferrous ions and hydrogen peroxide, and the auto-decomposition of hydrogen peroxide is reduced, thereby decreasing oxidant consumption while maintaining oxidation efficiency
Solution Approach 2:
The invention replaces the expensive and problematic iron catalyst system with a simple alkaline environment that uses readily available bases (NaOH, KOH, Ca(OH)2). The short-lived hydroxyl radicals are generated in situ and used immediately for oxidation without the need for continuous catalyst addition, reducing both material cost and complexity
2Productivity
If Fenton oxidation process is used to oxidize sulphur species, then oxidation can be performed, but iron containing sludge is generated causing economic and environmental challenges
Solution Approach 1:
The invention extracts and eliminates the iron catalyst component from the Fenton system by operating in alkaline conditions where iron would precipitate as inactive hydroxides. This removes the source of sludge generation entirely, as the oxidation is achieved through direct hydroxyl radical attack without iron cycle involvement
Solution Approach 2:
The invention converts the typically harmful acidic conditions and iron catalyst requirements into beneficial alkaline conditions that naturally suppress unwanted side reactions. The high pH environment that would normally be considered problematic becomes the key to reducing oxidant consumption and eliminating sludge formation
3Productivity
If Fenton oxidation process is used, then oxidation of sulphur species can occur, but strict pH control close to 3 is required which limits adaptability
Solution Approach 1:
The invention inverts the conventional approach by operating at high pH (9-11) instead of low pH (3). This inversion fundamentally changes the reaction dynamics, allowing the use of common bases rather than requiring precise acid control, and enables treatment of a broader range of wastewater compositions without strict pH maintenance
4Productivity
If gas-liquid interaction is used for oxidation, then sulphur species can be oxidized, but slow kinetics occur due to mixing energy requirements and surface area limitations
Solution Approach 1:
The invention changes the pH parameter to alkaline conditions, which increases the stability and lifetime of hydroxyl radicals. This allows the radicals to diffuse and react over longer distances and times, reducing the need for intensive mixing and enhancing mass transfer efficiency without requiring excessive mixing energy
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Achieves efficient oxidation of sulphur oxyanions to sulphate with reduced costs and improved reaction kinetics, allowing treatment in a wider pH range without catalysts, and minimizing waste generation.
Implementation Method 1
Aqueous liquid stream containing sulphur oxyanions is mixed, in at least one sparger device, with at least one oxidant in gaseous form, thereby obtaining, mixed within the aqueous liquid stream, reactive radicals species in contact with the at least one oxidant in gaseous form and the aqueous liquid stream
Implementation Method 2
The reactive radicals species are allowed to contact and oxidize sulphur oxyanions contained in the aqueous liquid stream to sulphate
Implementation Method 3
Aqueous liquid stream containing sulphur oxyanions is mixed, in at least one sparger device, with at least one oxidant in gaseous form
Implementation Method 4
enhancing oxidation efficiency through uniform distribution of microbubbles and nano droplets
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method is disclosed for oxidation of sulphur oxyanions contained in a stream of aqueous liquid. In the method, an aqueous liquid stream containing sulphur oxyanions is mixed, in a sparger device (7, 8), with at least one oxidant in gaseous form, thereby obtaining, mixed within the aqueous liquid stream, oxidant microbubbles containing reactive radicals species in contact with dissolved or condensed oxidant and the aqueous liquid stream, and/or reactive radicals species in contact with the at least one oxidant in gaseous form and the aqueous liquid stream. The dissolved or condensed oxidant and the reactive radicals species, and/or the at least one oxidant in gaseous form and the reactive radicals species, are allowed to contact sulphur oxyanions contained in the aqueous liquid stream and to oxidize sulphur oxyanions contained in the aqueous liquid stream to sulphate and/or to other sulphur oxidation states, by an oxidative reaction of the sulphur oxyanions with the reactive radicals species, thereby forming sulphate and/or other sulphur oxidation states containing aqueous liquid stream.