Off-Gas Recovery with Pressure Condensation and Regenerative Adsorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing soil vapor extraction (SVE) technologies are ineffective in removing halogenated chemicals and volatile organic compounds (VOCs) like chloromethane and freon due to their low condensation points, requiring extreme cooling and leading to increased costs and safety risks, and often result in frequent replacement of scrubbing reagents and potential hazards from heat-induced reactions.
Innovation Solution
An enhanced SVE system incorporating a vacuum and compression module, a vapor elimination module with condensation and regenerative adsorption using activated alumina adsorbers, which adsorbs and desorbs pollutants at different pressures to produce a contaminant-free exhaust, avoiding the need for high-temperature treatments and optimizing condensation processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional scrubbers are used to remove VOCs with low condensation points, then complete removal of pollutants is achieved, but extreme cooling is required which increases costs and safety risks
Solution Approach 1:
The system changes the pressure parameter of the off-gas from atmospheric to high pressure (using a compressor). This pressure change fundamentally alters the condensation behavior of VOCs, allowing them to condense at much higher temperatures than would be required at atmospheric pressure, thereby eliminating the need for extreme cooling
Solution Approach 2:
The system performs compression of the off-gas before the condensation step. This preliminary action of pressurizing the gas stream prepares it for efficient condensation at elevated temperatures, preventing the need for subsequent extreme cooling operations
2Reliability
If heat-induced reactions are used to treat off-gas, then pollutant destruction is achieved, but potential hazards and safety risks increase
Solution Approach 1:
The system utilizes phase transition (condensation) of VOCs from gas to liquid state through pressure-induced condensation. This physical phase change effectively removes pollutants without requiring heat-induced chemical reactions, thereby eliminating the safety hazards associated with thermal treatment while achieving complete pollutant destruction
Solution Approach 2:
The system replaces thermal/chemical treatment mechanisms with a mechanical pressure-based condensation mechanism. By using a compressor to pressurize the off-gas and induce condensation, the system substitutes potentially hazardous heat-induced reactions with a safer mechanical process that achieves the same pollutant removal goal
3Reliability
If scrubbing reagents are used frequently to treat off-gas, then pollutant removal is maintained, but operational costs increase due to frequent replacement
Solution Approach 1:
The system uses the off-gas itself (specifically, a portion of the cleaned off-gas) to facilitate the condensation process by serving as the cooling medium. This self-service approach eliminates the need for external scrubbing reagents and their frequent replacement, thereby reducing operational costs while maintaining consistent pollutant removal effectiveness
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
The system effectively removes a wide range of VOCs, including halogenated compounds, by optimizing condensation and adsorption processes, reducing costs and safety hazards, and achieving efficient remediation of contaminated soils with improved efficiency and safety compared to traditional methods.
Implementation Method 1
a vacuum source
Implementation Method 2
a compressor; compressing the off-gas to form a high pressure concentrated off-gas
Implementation Method 3
at least one condensation module to condense fluid from off gas
Implementation Method 4
a regenerative adsorbing module having a plurality of activated alumina adsorbers. Each adsorber adsorbs pollutants from a high pressure gas and desorbs the pollutants into a low pressure gas
Data Source
AI summary
An off gas extraction system provides superior results to other systems for cleaning polluted soil. Off gas is extracted, followed by compression and condensation. Compression and condensation produce an off gas that must be further treated to produce pollutant-free exhaust. A regenerative adsorber cleans the influent gas/air by adsorbing residual chemical vapor and concentrates the removed chemical vapor and reprocesses them. Conventional scrubbers are used on the back end of the system to produce a final exhaust as prescribed by environmental regulation. Methods of accomplishing the same are similarly provided, including unique business methods for conforming extraction plans with current environmental regulations and compliance impact generation based on an evolved knowledge base.