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Full-Text Articles in Environmental Engineering
Carbon Injection To Support In-Situ Smouldering Remediation, Gillian Wilton
Carbon Injection To Support In-Situ Smouldering Remediation, Gillian Wilton
Electronic Thesis and Dissertation Repository
Per- and polyfluoroalkyl substances (PFAS) are a group of anthropogenic contaminants that are growing increasing concern due to their associated negative health affects. The properties of PFAS result in their persistence and stability which present challenges for remediation. Activated carbon is currently the most widely used method for PFAS treatment since carbon microparticle injection can be used for in-situ treatment; however, this method does not result in PFAS destruction. Thermal treatment is a promising post-treatment method that can be used with activated carbon as long as sufficient PFAS-destroying temperatures are achieved (> 900°C). A promising in-situ thermal treatment technology is …
Hydrogen-Rich Syngas Derived From Smouldering Biomass And Hydrocarbon Wastes, Joshua K. Brown
Hydrogen-Rich Syngas Derived From Smouldering Biomass And Hydrocarbon Wastes, Joshua K. Brown
Electronic Thesis and Dissertation Repository
In the face of climate change, the world is looking to new fuel sources to meet the surging global energy demand. Hydrogen has been proposed as a promising energy vector being both a net-zero carbon emitter and having one of the highest gravimetric energy densities of known fuels. Production of hydrogen, however, is difficult with many of the technologies which exist today failing to be economically feasible or environmentally sustainable. Smouldering has recently been developed as a cost effective and energy efficient technology for destruction of organic wastes. The unique reaction zones created within a smouldering system have the potential …
Smouldering Combustion Treatment Of Soils And Granular Activated Carbon Contaminated With Per- And Polyfluoroalkyl Substances, Alexandra L. Duchesne
Smouldering Combustion Treatment Of Soils And Granular Activated Carbon Contaminated With Per- And Polyfluoroalkyl Substances, Alexandra L. Duchesne
Electronic Thesis and Dissertation Repository
Per- and polyfluoroalkyl substances (PFAS) are emerging contaminants, ubiquitous in the environment, and are challenging to remediate. Self-sustaining Treatment for Active Remediation (STAR) destroys organic contaminants embedded in porous media using smouldering combustion. Self-sustaining smouldering conditions allow the reaction to propagate through the contaminated media without external energy. This study explored STAR as a remediation option for PFAS-impacted granular activated carbon (GAC) and PFAS-contaminated soil. Three smouldering mixtures were used (i) PFAS-spiked GAC and sand, (ii) PFAS-spiked soil and GAC, (iii) PFAS-contaminated field site soil and GAC. Smouldering temperatures were greater than 900˚C, destroying the GAC. Post-treatment PFAS concentrations of …
The Influence Of Porous Media Heterogeneity On Smouldering Remediation, Jiahao Wang
The Influence Of Porous Media Heterogeneity On Smouldering Remediation, Jiahao Wang
Electronic Thesis and Dissertation Repository
Smouldering remediation is a promising technique for destroying organic contaminants in soil. Forced airflow is vital to supporting the smouldering reaction and to propagate it through the contaminated zone. This research focuses on investigating the effects of permeability heterogeneity on smouldering. A series of unique column experiments, combined with numerical model simulations, were conducted. The results suggest that smouldering can successfully propagate through layers in series despite more than a 1000:1 permeability contrast. However, extinction can occur in the finer layer when smouldering propagates through layers in parallel with a permeability ratio above 3:1. Extinction may occur due to insufficient …
Field Trials Of Ex Situ Smouldering Treatment (Starx) Of Oil Sludge, Cody Murray
Field Trials Of Ex Situ Smouldering Treatment (Starx) Of Oil Sludge, Cody Murray
Electronic Thesis and Dissertation Repository
Growing environmental concern and regulations around petroleum producing and refining facilities, along with the divesting of legacy properties, have necessitated the need for rapid, high capacity, and cost-effective treatment technologies for remediating these sites and their produced wastes. Self-sustained liquid smouldering – known as STAR technology - has been studied extensively at small scales and has been proven as an effective in situ remediation technique for heavy hydrocarbons. However, STAR as a large-scale ex situ waste disposal method (STARx) has yet to be demonstrated. Here STARx is evaluated for the first time in soil pile configurations, using an engineered base …
Field-Scale Implementation Of Sulfidated Nano Zerovalent Iron For In-Situ Remediation, Ariel Nunez Garcia
Field-Scale Implementation Of Sulfidated Nano Zerovalent Iron For In-Situ Remediation, Ariel Nunez Garcia
Electronic Thesis and Dissertation Repository
As far back as the mid-1990s, biogenic sulfidation has been observed during the implementation of iron-based materials for groundwater remediation. This phenomenon has largely been a consequence of natural biogeochemical processes and the prospects of utilizing engineered sulfidated zerovalent iron (ZVI) particles – nano- and/or micro- sized – were not extensively explored. More recently sulfidation of zerovalent iron (ZVI) particles has received considerable attention, highlighting the benefits that engineered/abiotic sulfidation can offer to nZVI, but to date, no field demonstration of the technology has been conducted. The first part of this thesis aims to report the unique challenges and unanswered …
Analysis And Control Of Aluminum Concentration In Groundwater: Mathematical Modelling And Laboratory Study, Daria Popugaeva
Analysis And Control Of Aluminum Concentration In Groundwater: Mathematical Modelling And Laboratory Study, Daria Popugaeva
Electronic Thesis and Dissertation Repository
The remediation of metal-contaminated natural water bodies is prioritized due to metals toxicity, non-biodegradable properties, and accumulative behaviours leading to the increased incidence of adverse health effects. Current investigation is driven by the existing problem of elevated aluminum concentrations in the groundwater of Khibiny alkaline massif (Kola Peninsula). The prohibitive aluminum level exceeding the accepted standard of 0.20 mg L−1 is described as a serious health concern when the groundwater used for the local water supply. The results of comprehensive field data analysis based on chemometric methods applied to the available monitoring data including 12 groundwater quality parameters are …
Role Of Zero Valent Iron And Organic Substrates In Chlorinated Solvent Degradation: An Ex-Situ Remediation Case Study, Alexander Stevenson
Role Of Zero Valent Iron And Organic Substrates In Chlorinated Solvent Degradation: An Ex-Situ Remediation Case Study, Alexander Stevenson
Electronic Thesis and Dissertation Repository
Field practice suggests that a combination of biotic and abiotic technologies to treat soil impacted by chlorinated solvents positively influences a remediation project’s success rate. Two large remediation programs have used a material containing both zero-valent iron (ZVI) and a dry organic substrate to abiotically reduce contaminants and increase anaerobic bioremediation in soil contaminated with tetrachloroethylene and 1,2-dichloroethylene using ex-situ mixing techniques. This research assesses the contributions made by the dry organic substrate and ZVI to the observed changes in chlorinated solvent concentrations by analyzing field samples collected from the sites previously remediated, as well as conducting bench-scale batch reactor …
Time-Lapse Electrical Resistivity Tomography For Mapping In Situ Smouldering Remediation (Star), Lais Muchatte Trento
Time-Lapse Electrical Resistivity Tomography For Mapping In Situ Smouldering Remediation (Star), Lais Muchatte Trento
Electronic Thesis and Dissertation Repository
Time-lapse Electrical Resistivity Tomography (ERT), a surface geophysical technique, was applied for the first time to monitor the first full-scale application of Self-sustaining Treatment for Active Remediation (STAR) at a coal tar contaminated site. STAR is a self-sustaining smouldering technology that destroys contaminants in situ by combustion, generating heat, water, and combustion gases. ERT is used as a complementary source of information to support conventional temperature and gas concentration data collected during STAR operations. A shallow (2.4 mbgs) and a deep (7.8 mbgs) treatment cell were monitored, with 2D surface resistivity surveys conducted before, during and after treatment. Two 36 …
Starx Technology For Waste Oil Sludge Treatment Investigated With Numerical Modelling, Rebecca L. Solinger
Starx Technology For Waste Oil Sludge Treatment Investigated With Numerical Modelling, Rebecca L. Solinger
Electronic Thesis and Dissertation Repository
Growing stockpiles of industrial liquid waste stored in lagoons are an outstanding problem worldwide. Self-sustaining Treatment for Active Remediation (STAR) is an emerging technology based on smouldering combustion that has been successfully deployed for in situ remediation of field sites (Grant et al., 2016). STAR is currently being developed as an ex situ treatment system (STARx) for industrial wastes by intentionally mixing them with sand. One engineering concept for STARx is the “hotpad”, for which some initial experiments have been conducted. However, a thorough experimental investigation is challenging due to the cost and time associated with each experiment. This work …
Hydraulic And Electrokinetic Delivery Of Remediants For In-Situ Remediation, Ahmed I. A. Chowdhury
Hydraulic And Electrokinetic Delivery Of Remediants For In-Situ Remediation, Ahmed I. A. Chowdhury
Electronic Thesis and Dissertation Repository
Nano-scale zero valent iron (nZVI) has shown promising mobility and in-situ reactivity with chlorinated volatile organic compounds when injected into saturated porous media. The current study evaluated nZVI mobility and subsequent reactivity with in-situ contaminants in a variably saturated porous media. The nZVI particles, synthesized onsite at subzero temperatures, demonstrated complete trichloroethene (TCE) degradation within the target area. Furthermore, a three dimensional finite difference model (CompSim) was utilized to investigate nZVI mobility in variably saturated zones. Model predicted well head data were in very good agreement with field observations. Simulation results showed that the injected slurry migrated radially outward from …
Smouldering Remediation: Transient Effects Of Front Propagation, Laura L. Kinsman
Smouldering Remediation: Transient Effects Of Front Propagation, Laura L. Kinsman
Electronic Thesis and Dissertation Repository
Remediation of sites contaminated with non-aqueous phase liquids (NAPLs) presents a significant challenge, particularly for complex and high molecular weight compounds such as coal tar and creosote. Self-sustaining Treatment for Active Remediation (STAR) is an innovative remediation technology based on the principles of smouldering combustion, which has shown potential for rapid destruction of source zone contaminants. The success of smouldering remediation has been previously demonstrated both at the laboratory and field scale, however, these studies have focused primarily on the overall degree of remediation. Laboratory column experiments were employed to identify key transient processes that have the potential to influence …
Electrical Resistivity Tomography For Mapping Subsurface Remediation, Christopher Power
Electrical Resistivity Tomography For Mapping Subsurface Remediation, Christopher Power
Electronic Thesis and Dissertation Repository
Cleaning up sites contaminated with dense non-aqueous phase liquids (DNAPLs) remains a challenging geoenvironmental problem. The performance of site remediation methods is difficult to assess without a practical, non-destructive technique to map where and how quickly DNAPL mass is being reduced. The promise of electrical resistivity tomography (ERT) in this context has not been realized, in part because traditional ERT methods were used to solve the near-impossible problem of mapping the initial DNAPL outline. However, new developments in ERT have emerged that focus on resolving subsurface changes over time. The objective of this work was to evaluate the potential of …
Smouldering Combustion For Soil Remediation: Two-Dimensional Experiments And Modelling, Tanzeer Hasan
Smouldering Combustion For Soil Remediation: Two-Dimensional Experiments And Modelling, Tanzeer Hasan
Electronic Thesis and Dissertation Repository
Sustaining Treatment for Active Remediation (STAR) is a novel technology for the remediation of soils contaminated with Non-Aqueous Phase liquids (NAPLs). STAR is based upon the concept of liquid smouldering, in which NAPLs embedded in a porous medium are progressively destroyed via an exothermic oxidation reaction which propagates in a self-sustaining manner through the contaminated material. The In Situ Smouldering Model (ISSM), developed to simulate the propagation of STAR as a function of NAPL content and local air velocity, was calibrated for a suite of one-dimensional experiments (MacPhee et al., 2010). However, STAR application at field sites involves propagation of …