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- Particle Transport in Fractures (2)
- Air Emissions from Waste Incineration (1)
- Air pollutants (1)
- Assessment of Air Pollution Control Systems (1)
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- Colloid transport (1)
- Differential transport (1)
- Discontinuous Gas Phase in PM (1)
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- Human impacts (1)
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- Medical waste (1)
- Palaeoecology (1)
- Single fracture (1)
- Stack emissions (1)
- Starved air gasification (1)
- Variable-aperture fracture (1)
- Velocity distributn assioumption (1)
- Waste incineration (1)
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Articles 1 - 5 of 5
Full-Text Articles in Physical Sciences and Mathematics
Palaeoecology: A Tool To Improve The Management Of Australian Estuaries, Krystyna M. Saunders, Kathryn H. Taffs
Palaeoecology: A Tool To Improve The Management Of Australian Estuaries, Krystyna M. Saunders, Kathryn H. Taffs
Dr Kathryn H Taffs
Addressing environmental problems in estuaries is a worldwide problem. Establishing benchmarks and targets for management is critical, whether the aim is conservation, restoration or ‘sustainable wise use’. Palaeoecological techniques have rapidly improved during the past decade, particularly with advances in methods that allow high resolution quantitative assessments of environmental change, allowing pre-impact conditions, the rate, extent and direction of change, and range of natural variability to be determined. Australian estuarine ecosystems are qualitatively different to the often more well-studied estuaries in North America and Europe, which means site-specific studies of Australian estuaries are needed to inform management. While a potentially …
New Observations Of Gas-Phase Expansion Above A Dense Non-Aqueous Phase Liquid Pool, Kevin G. Mumford, James E. Smith, Sarah E. Dickson
New Observations Of Gas-Phase Expansion Above A Dense Non-Aqueous Phase Liquid Pool, Kevin G. Mumford, James E. Smith, Sarah E. Dickson
Sarah E Dickson
The partitioning of volatile dense nonaqueous phase liquid (DNAPL) compounds to a discontinuous gas phase results in the repeated expansion, fragmentation, and vertical mobilization of gas clusters. This process has the potential to significantly affect the dissolution of DNAPL source zones and the characterization of DNAPL-contaminated sites, but has not been included in common conceptual models. This study presents new observations of discontinuous gas-phase growth above a 1,1,1-trichloroethane pool in a two-dimensional flow cell packed with 1.1-mm diameter sand. In contrast to the behavior observed in coarse glass beads, these visualization results show that the gas phase evolves as a …
Influence Of Aperture Field Heterogeneity And Anisotropy On Dispersion Regimes And Dispersivity In Single Fractures, Qinghuai Zheng, Sarah E. Dickson, Yiping Guo
Influence Of Aperture Field Heterogeneity And Anisotropy On Dispersion Regimes And Dispersivity In Single Fractures, Qinghuai Zheng, Sarah E. Dickson, Yiping Guo
Sarah E Dickson
A 33 factorial experimental design was implemented to numerically investigate the interactive effect of the mean (μ b ), standard deviation (σ b ), and anisotropic ratio (AR) (λ b x /λ b y ) of single-fracture apertures on dispersion regimes (specifically Taylor dispersion and geometric dispersion) and dispersivity. The Reynolds equation was solved to obtain the flow fields in each computer-generated fracture, and the random walk particle tracking method was used to simulate solute transport. The simulation results show that (1) for a fixed hydraulic gradient, the dominant dispersion regime is controlled by μ b , and to a …
Differential Transport And Dispersion Of Colloids Relative To Solutes In Single Fractures, Qinghuai Zheng, Sarah E. Dickson, Yiping Guo
Differential Transport And Dispersion Of Colloids Relative To Solutes In Single Fractures, Qinghuai Zheng, Sarah E. Dickson, Yiping Guo
Sarah E Dickson
This work employed numerical experiments simulating colloid and solute transport in single parallelplate fractures, using the random walk particle tracking method, to demonstrate that (1) there exists an aspect ratio of the colloid radius to half the fracture aperture, do, where the average velocities of colloids and solutes are similar. When d > do, the velocity distribution assumption is satisfied, and the fact that the ratio of the colloid transport velocity to the solute transport velocity, sp, decreases as d increases is well documented in the literature. However, when d < do, the velocity distribution assumption is violated, and sp increases as d increases and (2) the Taylor dispersion coefficient and its extension by James and Chrysikopoulos [S.C. James, C. V. Chrysikopoulos, J. Colloid Interface Sci. 263 (2003) 288] will overestimate the colloid dispersion coefficient significantly. Additionally, numerical experiments simulating colloid and solute transport in variable-aperture fractures demonstrated that sp and DL,coll /DL,solute decrease with increasing CoV, and the anisotropy ratio only plays a minor role compared to the CoV. These observations have important implications towards the interpretation of colloid transport in both porous and fractured media.
Suchy System Oczyszczania Spalin Ze Spalania Odpadów Niebezpiecznych – Ocena Skuteczności Usuwania Substancji Gazowych I Możliwości Spełniania Standardów Emisyjnych, Robert Oleniacz
Robert Oleniacz
The research object was a medical waste incineration plant with a flue-gas treatment system based on dry sorption agent injection to combustion gases before a high-efficiency particulate collector. A combustion system was consisted with the fluidized bed reactor (starved air gasifier) and the secondary combustion chamber. As the dry absorbent was used a mixture of high reactive hydrated lime and activated carbon. Activated carbon content in the mixture was 5-10 % by mass. The absorbent was injected in the minimal recommended amount (4-5 kg/h). Applied collector was a ceramic filter with total filtration area of 120 m2 and guaranteed outlet …