While oil sands companies are expected to reclaim liquid tailings, there has been 40 years of poor performance in addressing this longterm liability. Rheology for deposition control of polymeramended oil sands. Geochemical characteristics of oil sand tailings and bitumen. Mamadou fall in partial fulfillment of the requirements for the degree of master of applied science in environmental engineering department of civil engineering university of ottawa ottawa, canada april, 20. They are a mix of water, sand, silt, clay, unrecovered hydrocarbons, and other contaminants. Sand is defined as having a particle size greater than 44 microns and fines have particle sizes less than 44 microns. To manage the volumes effectively, engineers must be able to predict a rate of compression of these tailings. Funding was provided by the canadian oil sands innovation alliance cosia and the natural science and engineering research council of. Join keith and rita in conversations that matter, a series of short videos about albertas oil sands the alberta energy regulators role. Consolidation testing of oil sand fine tailings ubc. Requirements under the framework will be administered primarily through the oil sands conservation act and the environmental protection and enhancement act.
Geochemical characteristics of oil sand tailings and bitumen upgrading byproducts, alberta, canada bronwenforsyth, stephen day, srk consulting canada inc. Ercb approved s23 production accounting manual, interim directive id 200107. Comparison of hydraulic conductivity of oil sands fine tailings. Oil sands tailings oil sand is composed of 8085% mineral, 1015% bitumen and 34% water by weight. Fine tailings either mature fine tailings or free fine tailings was thickened to a tailings mud, then the tailings mud and coarse sand were placed in alternative layers in a 100 l container, water released from the interlayered. Tailings directive 074 explained oil sands magazine. Geochemical characteristics of oil sand tailings and. Flocculation of limetreated oil sands tailings sciencedirect. The particlesize distribution of oil sands tailings has always figured prominently in the mine planning and overall operations and closure strategy in surfacemined oil sands. Oil sands tailings are a mixture of water, sand, fine silts, clay, residual bitumen and lighter hydrocarbons, inorganic salts and. Feb 03, 2016 composite tailings ct, an engineered, alkaline, saline mixture of oil sands tailings fft, processed sand and gypsum caso 4. Sap based rapid dewatering of oil sands mature fine tailings by aida farkish a thesis submitted under the supervision of dr.
Oil sand tailings contain a mixture of salts, suspended solids and other dissolvable chemical compounds such as acids, benzene, hydrocarbons residual bitumen, fine silts and water. New federal research has strongly backed suspicions that toxic chemicals from albertas vast oil sands tailings ponds are leaching into groundwater and seeping into the athabasca river. The resulting composite sandclay particles settle and dewater rapidly to a stackable product that can be handsqueezed to 4083 wt% solids. Oil sands operators tackle tailings management challenges. Tailings are stored in basins called tailings ponds, which allow the solids in tailings to settle. The mineral component of the oil sand contains both sand and fines. The insitu method of accessing oil sands resources does not produce tailings. Tailings producers are now being required to have plans in place such that it is possible to demonstrate the achieving of five kpa of shear strength within oilsand tailings deposits. Three quarters of albertas oil sands reserves are located in the athabasca region, which are mostly recovered by openpit mining natural resources canada, 2015. Guidelines for performance management of oil sands fluid fine. Oil sands tailings management natural resources canada. Technical guide for fluid fine tailings management cosia. University of calgary characterization of oil sands tailings.
Showdown looming for albertas oilsands over cleanup of. Fluid tailings management for oil sands mining projects october 2017 necessary to ensure it appropriately enables and aligns with changes in the. Proceedings tailings and mine waste 2011 vancouver, bc, november 6 to 9, 2011 consolidation testing of oil sand fine tailings dobroslav znidarcic and robert miller university of colorado, boulder, usa dirk van zyl mining engineering, university of british columbia, vancouver, canada murray fredlund soilvision systems ltd. Tailings ponds are massive earth structures used to store coarse and fine solids contained in the oil sands deposit and recover water back to the main processing plant. Cms workshop lectures volume 22 introduction to oil sands clays organized by daryl hockley srk consulting canada inc. Along with the 2030 wt% of solids sands and clays and slightly alkaline water ph7. Consolidation testing of oil sand fine tailings ubc library.
The role of clays in the performance of oilsands tailings. These ponds are temporary storage facilities and need to be reclaimed when no longer in use. Oil sands tailings pond water tpw according to canadas oil sands innovation alliance cosia, an alliance of oil sands producers formed in 2012, who share research on environmental priority areas epas such as tailing pond water and greenhouse gases, tailings are the sand, silt, clay and water found naturally in oil sands that remain following the mining and bitumen extraction process. Funding was provided by the canadian oil sands innovation alliance cosia and the natural science and engineering research council of canada nserc. In addition, the aer will continually improve the directive based on observations as to the.
Original paper chemical composition of weathering products. In northern alberta, canada, oil sands industries produce large volumes of tailings. Guidelines for performance management of oil sands fluid fine tailings deposits to meet closure commitments february 2014 canadas oil sands innovation alliance page ii this document further defines the process to manage and report annual and fiveyear progress to regulators, for control of fft volumes on each mine site, consistent with. Oil sands tailings and directive 074 oil sands mining operations produce significant quantities of liquid waste materials called tailings. Oil sands tailings ponds are engineered dam and dyke systems used to capture oil sand. Oil sands tailings are a mixture of water, sand, fine silts, clay, residual bitumen and lighter hydrocarbons, inorganic salts and watersoluble organic compounds. In 2008, the former ercb alberta energy resources conservation board, now known as the alberta energy regulator introduced directive 074.
The composition of this manmade material and its influence on the insitu state of tailings is of particular importance. The dewatering of oil sand tailings has become more imperative in the past few years with the creation of directive 074. In order to investigate the feasibility of oil sands tailings filtration, we conducted a series of benchscale filtration tests. Beside its contribution to greenhouse gas emissions, methanogenesis was shown to increase tailings densification. What are tailings and why are people talking about them. Not only have microbes profoundly affected the composition and. Oil sands tailings are a mixture of water, sand, fine silts, clay, residual bitumen and lighter hydrocarbons, inorganic salts and watersoluble organic. May 23, 2017 the authors would like to acknowledge shell canada for providing mft and polymer samples and oil sand tailings research facility ostrf. Sand, clay and other solid particles contained in oil sands tailings does not include bitumen. The objective of this study was to investigate the filterability of the tailings and the effect of various factors, such as tailings composition fines content and flocculant addition, on filtration performance. Members, metagenomics and ecophysiology, handbook of hydrocarbon and lipid. Pdf the oil sands research and information network. Use of toxicity tests in studies of oil sands tailings water detoxification.
The most common sulphide at both sites was pyrite fes. Sulfur biogeochemistry of an oil sands composite tailings. Review of the composition and toxicity of oil sands processaffected. Albertas oil sands miners are testing a variety of methods to process and manage tailings that meet the requirements of a tough new governmental directive.
A method for oil sands tailings consolidation to a trafficable surface soon after its disposal was developed. A blend of mft and sand used to dispose of fine tailings. Based on the results of this thesis, ct srb appear to have a greater ability than irb to utilize recalcitrant oc e. Finely ground rock particles ranging from sandsized to siltsized. The claydominated fine mineral solids contained in the water runoff from the mainly sand tailings discharged from the oil sands bitumen extraction process. W aterfowl that land on oilsands tailings ponds can become coated in oil, causing them to sink to the bottom. The authors would like to acknowledge shell canada for providing mft and polymer samples and oil sand tailings research facility ostrf. Most existing oil sand tailings are stored in large ponds which have been shown to be consolidating very slowly. Metabolism begins with betaoxidation of naphtha such as long and short nalkanes to acetate and h2 by syntrophussmithella.
Oil sand tailings or oil sands processaffected water ospw, have a highly variable composition and a complex mixture of compounds. Fine solids from tailings streams tend to trap large volumes of water, making pond reclamation challenging at best. Large volumes of tailings are a byproduct of bitumen extraction from the oil sands and managing these tailings is one of. Microbial sulfur biogeochemistry of oil sands composite. Geotechnical properties of mine tailings journal of. Delft university of technology dewatering behaviour of fine oil. Federal study says oil sands toxins are leaching into. The objective of this study was to investigate the filterability of the tailings and the effect of various factors, such as tailings composition fines.
Suncor energy inc, canada abstract few studies have characterized the metal leaching and acid rock drainage mlard potential of. Nrcancetc devon facility and location of the oil sands tailings research facility the ostrf is a unique academic and industrial research facility dedicated to collaborative and multidisciplinary tailings research. However, it will fill a management gap by providing a framework in which to monitor and manage longterm fluid tailings accumulation and reclamation on the landscape in the lower athabasca region. We conducted investigations of the feasibility of recovering asphaltenes from the tailings. Sap based rapid dewatering of oil sands mature fine tailings. Tailings, a lasting oil sands legacy wwfcanada, october 2010 3 today four operators suncor, syncrude, shell and canadian natural resources ltd. Under this new directive, oil sands mining operators are required by law to commit to the reduction of fine fluid tailings and reduce any current inventories.
A good starting point is to understand the composition of the oil sands deposits. Geochemical characteristics of oil sand tailings and bitumen upgrading byproducts, alberta, canada bronwen forsyth1, stephen day1 and oladipo omotoso2 1. Oil sands tailings ponds are engineered dam and dyke systems used to capture oil sand tailings. The oil sands tailings ponds are settling ponds that contain the waste byproduct of oil sands extraction and upgrading. A research program was therefore initiated at the university of pretoria, to investigate the composition and state of south african gold tailings on the far west rand gold reefs. Albertas oilsands could be heading for another showdown over tailings ponds after an independent assessment found that the cleanup plans of six major operators dont meet new rules.
Composite tailings ct, an engineered, alkaline, saline mixture of oil sands tailings fft, processed sand and gypsum caso 4. Sulfur biogeochemistry of an oil sands composite tailings deposit. Oct 31, 2012 after solvent recovery, the asphaltenes, water, and mineral solids are discharged as froth treatment tailings. A study on chemical stabilization of oil sands mature fine tailings yixuan wang. We identified 34 oil sands tailings treatment technologies that are discussed. Oil sands operators tackle tailings management challenges e. Guidelines for performance management of oil sands fluid. Bitumen is separated from oil sand using the clark hot water. Current knowledge of seepage from oil sands tailings ponds and its. Tailings producers are now being required to have plans in place such that it is possible to demonstrate the achieving of five kpa of shear strength within oil sand tailings deposits in reasonable times.
Tailings bulk composition showed enrichment of co, mo. Tailings ponds a toxic legacy of albertas oilsands the star. The aim of this report is to serve as a fundamental planning document for future research initiatives by osrin and other research agencies to support, promote, and improve the oil sands industrys capability to deal with the challenges of fine tailings management. A study on chemical stabilization of oil sands mature fine. Wang, yixuan, a study on chemical stabilization of oil sands mature fine tailings 2017. Tailings ponds a toxic legacy of albertas oilsands. Thickening of mature fine oil sands tailings thesis format.
Chemical composition of weathering products in neutral and acidic mine tailings from stibnite exploitation in slovakia. In addition to h 2 s, methane contributes to 6080% of gas flux over oil sands tailings ponds. The oil sands mining and extraction processes in canada produce large volumes of tailings that are. The majority of the fines separate or segregate during tailings. Oil sands processaffected water has been researched for decades. The values of c c of the coal wash tailings and the fine oil sand tailings are 0. An investigation of the use of inline thickened tailings to create composite tailings at a sand to fines ratio, sfr, of 4. Oil sands tailings can be thought of as being made up of two major solids components. Mar 30, 2017 albertas oilsands could be heading for another showdown over tailings ponds after an independent assessment found that the cleanup plans of six major operators dont meet new rules. Whole oil sands tailings resulting from waterbased bitumen extraction processes can be coflocculated, after treatment with slaked lime, with low dosages of a high molecular weight anionic polyacrylamide. The comparison of c c for different tailings indicates that the oil sand tailings and coal wash tailings have a higher compressibility than the other metal tailings, and for the same type of tailings, the. Requirements under the framework will be administered primarily through the oil sands conservation act and the environmental protection and. Oct 06, 2015 what are tailings and why are people talking about them.
Oil sands tailings harbor diverse microbes that generate greenhouse gases. We identified 34 oil sands tailings treatment technologies that are discussed and analyzed. The asphaltenes contained in the tailings constitute valuable hydrocarbons that, if recovered, could be useable as coker feed or paving material. Predicting oil sands tailings behaviour from clay content.
Anaerobic methanogenic hydrocarbon degradation is the source of ch4 emissions in tailings ponds. Rheology for deposition control of polymeramended oil. Oil sands operators tackle tailings management challenges albertas oil sands miners are testing a variety of methods to process and manage tailings that meet the requirements of a tough new governmental directive by russell a. Nov 30, 2011 proceedings tailings and mine waste 2011 vancouver, bc, november 6 to 9, 2011 consolidation testing of oil sand fine tailings dobroslav znidarcic and robert miller university of colorado, boulder, usa dirk van zyl mining engineering, university of british columbia, vancouver, canada murray fredlund soilvision systems ltd. Understanding the implications of the composition of ospw for industrial. Following over two years of consultation and planning, the oil sands tailings consortium ostc was formally launched december 10, 2010 to facilitate cooperation with the objective of accelerating development of tailings management technology and practices. Ultraviolet light is an economical and simple way to clean up the residue, or tailings, left over from extracting oil from canadian tar sands. In handbook on theory and practice of bitumen recovery from athabasca oil sands. Tailings, and characteristics of oil sands tailings ponds. Mine tailings are usually produced from the mill in slurry form, which is a mixture of sunrise dam in western australia and bulyanhulu gold mine in tanzania. The acetate produced is coupled to methanogenesis either by acetoclastic methanogens to generate ch4 gas directly from acetate.