Electrokinetic Persulfate Delivery for Low Permeability Soil Remediation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for decontaminating organic contaminants in low permeability soils are inefficient, environmentally unfriendly, and have high carbon footprints, as they often require excavation, heat application, or limited oxidant delivery, which are not cost-effective or sustainable.
Innovation Solution
The method involves using direct current electric fields to transport persulfate oxidant through soils via electromigration or electroosmosis, followed by heating with alternating current to activate the oxidant, allowing for in situ treatment of contaminants with reduced energy input and carbon footprint.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If excavation and disposal in landfills is used to remove organic contaminants from low permeability soils, then contaminants are removed from the site, but the process involves transplacement of contaminants to another location and has high environmental impact and cost
Solution Approach 1:
The patent applies electrokinetic principles to deliver oxidants through low permeability soils, converting the challenging low permeability condition into a treatable scenario by using electrical fields to drive contaminant oxidation in place, thereby avoiding excavation and landfill disposal while eliminating harmful environmental impacts
Solution Approach 2:
The patent extracts and eliminates the need for excavation and physical contaminant transplacement by implementing in situ chemical oxidation through electrokinetic delivery of oxidants, thereby removing contaminants from the site without physical displacement to landfills
2Reliability
If heat is applied to volatilize contaminants and capture via vacuum in low permeability soils, then contaminants are treated, but the process has high energy consumption and environmental unfriendly carbon footprint
Solution Approach 1:
The patent replaces the mechanical/thermal system of heat application and vacuum capture with an electrochemical system using electrokinetic oxidant delivery and in situ chemical oxidation, thereby achieving contaminant degradation with significantly reduced energy consumption and eliminated carbon footprint
Solution Approach 2:
The patent changes the fundamental treatment parameters from high-temperature thermal processes to ambient or near-ambient temperature electrochemical oxidation, thereby reducing energy consumption while maintaining effective contaminant degradation
3Adaptability or versatility
If oxidant injection is used to degrade contaminants in permeable soils, then contaminants are degraded in place, but the approach is limited to permeable soils and cannot effectively treat low permeability soils
Solution Approach 1:
The patent introduces electrical fields as an intermediary mechanism to deliver oxidants through low permeability soils, overcoming the natural resistance to oxidant transport and enabling effective treatment of previously intractable soil types
Solution Approach 2:
The patent employs dynamic electrokinetic processes that can adapt to varying soil permeability conditions, allowing the oxidant delivery system to respond to and overcome the specific challenges of low permeability soils while maintaining versatility across different soil types
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
This approach effectively degrades contaminants in place within low permeability soils with moderate energy application, reducing environmental impact and carbon footprint compared to conventional heat-based methods.
Implementation Method 1
electromigration and/or electroosmosis of an oxidant throughout the soil and pore water by means of an applied direct current
Implementation Method 2
electromigration and/or electroosmosis of an oxidant throughout the soil and pore water by means of an applied direct current
Implementation Method 3
heating of the soil and pore water, for example, to at least 30° C. by an applied alternating current
Data Source
AI summary
A method for remediating contaminated soil includes adding a heat-activated oxidizing agent into the soil; exposing the soil to direct current through a first set of electrodes so as to cause migration of the oxidizing agent through the soil and pore water contained in the soil; and exposing the soil to alternating current through a second set of electrodes so as to heat the soil and thus to activate the oxidizing agent. The first and second sets of electrodes are optionally the same set.