Hydrodynamics of a large oil sand tailings impoundment and related environmental implications

2009 ◽  
Vol 46 (12) ◽  
pp. 1446-1460 ◽  
Author(s):  
G. P. Ferguson ◽  
D. L. Rudolph ◽  
J. F. Barker
Keyword(s):  
Groundwater Flow ◽  
Environmental Impacts ◽  
Flow Characteristics ◽  
Coarse Sand ◽  
Process Water ◽  
Oil Sand ◽  
Environmental Implications ◽  
Fine Tailings ◽  
Flow Pathways

Oil sand mine tailings are primarily contained by dykes constructed of permeable sand tailings. The environmental impacts of process waters released from these tailings facilities are controlled by groundwater flow within the impoundment structures. Transient groundwater flow characteristics were assessed within the Tar Island Dyke structure at the Suncor Inc. site near Fort McMurray, Alberta, to assist in quantifying potential long-term environmental impacts. A sequence of low-permeability fine tailings underlying the tailings water pond is supported by coarse sand tailings that are connected to and form the containment dyke structure. A clay unit separates the foundation from the underlying limestone that is hydraulically connected to the Athabasca River. The primary groundwater flow pathways are through the toe of the dyke and through the foundation. Field data and numerical simulations indicate that drainage of process water within the structure remains transient yet decreases over time. The fine tailings and pond become perched atop unsaturated coarse tailings, significantly restricting seepage and producing an environmental legacy with reclamation implications. The release of potentially contaminated process water continues to decrease, resulting in diminishing environmental risk. The lowering of pore-water pressures within the main dyke has increased its strength and long-term stability.

Interpreting the seasonal and long-term trend of nitrate in both groundwater and spring water in a typical headwater wetland with well-defined groundwater flow pathways

2016 ◽  
Vol 16 (5) ◽  
pp. 1327-1338
Author(s):  
Yingjie Cao ◽  
Changyuan Tang ◽  
Zhiwei Han ◽  
Sako Yoko ◽  
Xing Li
Keyword(s):  
Groundwater Flow ◽  
Soil Water ◽  
Residence Time ◽  
Spring Water ◽  
Hydrological Process ◽  
Term Trend ◽  
Increasing Trend ◽  
Flow Pathways ◽  
Long Term Trend

Timescale problems of nitrate behavior (i.e. seasonal variation and long-term trend) in headwater are closely related to its hydrological process. In a typical agricultural headwater catchment in the Chiba prefecture, Japan, the groundwater nitrate concentration showed an increasing trend, while for spring water, a substantial decreasing trend was observed during our monitoring period. Two key issues, (1) identification of multiple flow pathways and (2) evaluation of the residence time for different pathways, were emphasized to reveal the factors controlling the different patterns of nitrate trend. Three major flow pathways including vertical soil water flow (VF), lateral groundwater flow (LG) and deep groundwater flow (DG) along the upland-slope-valley were differentiated. Different timescales of three flow pathways were identified. The residence time of VF was calculated as 9–10 years based on the soil water budget equation and the apparent age of LG was estimated as 41 years by chlorofluorocarbon (CFC) traces. The increasing trend of NO3− in groundwater agreed well with the historical nitrate loading, and the decreasing trend of NO3− in spring was mainly influenced by nitrate behavior of LF, which substantially decreased due to reduction of nitrogen fertilizer loadings since 2000.

Chemical Disequilibrium In Oil Sand Fine Tailings

1991 ◽  
Author(s):  
R. Jonasson ◽  
Z. Zhou ◽  
R. Schutte ◽  
L. Danielson
Keyword(s):  
Oil Sand ◽  
Fine Tailings

Research on the Economic Organization Environmental Impact

2017 ◽  
Vol 68 (3) ◽  
pp. 599-601
Author(s):  
Dan Paul Stefanescu ◽  
Oana Roxana Chivu ◽  
Claudiu Babis ◽  
Augustin Semenescu ◽  
Alina Gligor
Keyword(s):  
Economic Activity ◽  
Economic Organization ◽  
Economic Activities ◽  
Environmental Implications ◽  
Minimal Impact ◽  
Wide Range ◽  
Material Environment ◽  
Negative Effect ◽  
Harmful Effects

Any economic activity carried out by an organization, can generate a wide range of environmental implications. Particularly important, must be considered the activities that have a significant negative effect on the environment, meaning those which pollute. Being known the harmful effects of pollution on the human health, the paper presents two models of utmost importance, one of the material environment-economy interactions balance and the other of the material flows between environmental factors and socio-economic activities. The study of these models enable specific conditions that must be satisfied for the economic processes friendly coexist to the environment for long term, meaning to have a minimal impact in that the residues resulting from the economic activity of the organization to be as less harmful to the environment.

scholarly journals Surface water and groundwater interaction at long-term exploited riverbank filtration site based on groundwater flow modelling (Mosina-Krajkowo, Poland)

2021 ◽  
Vol 37 ◽  
pp. 100882
Author(s):  
Magdalena Matusiak ◽  
Krzysztof Dragon ◽  
Jozef Gorski ◽  
Roksana Kruc-Fijałkowska ◽  
Jan Przybylek
Keyword(s):  
Surface Water ◽  
Groundwater Flow ◽  
Riverbank Filtration ◽  
Flow Modelling ◽  
Surface Water And Groundwater ◽  
Groundwater Flow Modelling

Case study on the implementation of deammonification for the process water treatment of Munich WWTPs

2012 ◽  
Vol 65 (10) ◽  
pp. 1895-1902 ◽  
Author(s):  
Rita Hilliges ◽  
Eberhard Steinle ◽  
Bernhard Böhm
Keyword(s):  
Water Treatment ◽  
Operating Costs ◽  
Process Water ◽  
Second Stage ◽  
Sludge Disposal ◽  
Sludge Digestion ◽  
High Investment ◽  
Flow Treatment

The two-staged WWTP ‘Gut Grosslappen’ has a capacity of 2 mio. PE. It comprises a pre-denitrification in the first stage using recirculation from the nitrifying second stage. A residual post-denitrification in a downstream sand filter is required in order to achieve the effluent standards. Presently the process water from sludge digestion is treated separately by nitrification/denitrification. Due to necessary reconstruction of the biological stages, the process water treatment was included in the future overall process concept of the WWTP. A case study was conducted comparing the processes nitritation/denitrititation and deammonification with nitrification/denitrification including their effect on the operational costs of the planned main flow treatment. Besides the different operating costs the investment costs required for the process water treatment played a significant role. Six cases for the process water treatment were compared. As a result, in Munich deammonification can only be recommended for long-term future developments, due to the high investment costs, compared with the nitritation/denitritation alternative realizable in existing tanks. The savings concerning aeration, sludge disposal and chemicals were not sufficient to compensate for the additional investment costs. Due to the specific circumstances in Munich, for the time being the use of existing tanks for nitritation/denitritation proved to be most economical.

Addition of Tubifex accelerates dewatering of oil sands tailings

2016 ◽  
Vol 43 (12) ◽  
pp. 1025-1033 ◽  
Author(s):  
Xiaojuan Yang ◽  
Miguel de Lucas Pardo ◽  
Maria Ibanez ◽  
Lijun Deng ◽  
Luca Sittoni ◽  
...  
Keyword(s):  
Oil Sands ◽  
Land Reclamation ◽  
Test Results ◽  
Anionic Polymer ◽  
Fine Tailings ◽  
Fluid Fine Tailings ◽  
Oil Sands Tailings ◽  
Set Up ◽  
Solids Content

Accelerating dewatering of fluid fine tailings (FFT) to facilitate land reclamation is a major challenge to the oil sands industry in Canada. A new method was tested, addition of Tubifex to FFT. Tubifex is an indigenous earthworm in Canada. The survival rate tests showed that Tubifex can survive in oil sands tailings and penetrate to 42 cm depth (maximum depth tested). Columns (5 L of FFT) were set-up with tailings alone, Tubifex treated tailings and polymer-Tubifex treated tailings. Test results showed that (a) the final mud–water interface of tailings alone was 26% higher than that of Tubifex treated tailings; (b) solids content of Tubifex treated tailings was 21% more than that of tailings alone; (c) Tubifex was capable to accelerate the dewatering process of both cationic and anionic polymer treated tailings; (d) anionic polymer was superior in facilitating long-term dewatering and its coupled effects with Tubifex were better than the cationic polymer.

Effects of Stator Configurations on the Flotation Performance of Induced Gas Flotation Machine

2016 ◽  
Author(s):  
Ji-Gu Lee ◽  
Ji-Yun Kang ◽  
Youn-Jea Kim
Keyword(s):  
Flow Characteristics ◽  
Chemical Plants ◽  
Oil Sand ◽  
Two Phase ◽  
Ansys Cfx ◽  
Commercial Code ◽  
Flotation Cell ◽  
Flotation Performance ◽  
Forced Air ◽  
Phase Water

Induced Gas Flotation (IGF) vessel is used for water treatment of plant industries such as oil sand and chemical plants. An understanding of the interaction between the stator and rotor is essential for the design of IGF with consideration of geometric blade configuration is essential for the design of IGF. In this study, the effect of the number of stator blades on flotation performance was numerically investigated using the commercial code, ANSYS CFX ver. 16.1. The two-phase (water and air) flow characteristics in the forced-air mechanically stirred Dorr-Oliver flotation cell were considered. The flotation performance was evaluated on the basis of the correlations among the number of stator blades (8, 12, 16, 20, 24), power number and void fraction. By comparing the result of each case, the newly designed model with 12 stator blades which had the highest flotation performance was derived.

Controlling factors and environmental implications of mercury contamination in urban and agricultural soils under a long-term influence of a chlor-alkali plant in the North–West Portugal

2008 ◽  
Vol 57 (1) ◽  
pp. 91-98 ◽  
Author(s):  
A. Cachada ◽  
S. M. Rodrigues ◽  
C. Mieiro ◽  
E. Ferreira da Silva ◽  
E. Pereira ◽  
...  
Keyword(s):  
Agricultural Soils ◽  
Controlling Factors ◽  
Mercury Contamination ◽  
Environmental Implications ◽  
North West ◽  
The North
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