Polymer aids for settling and filtration of oil sands tailings

Abstract

Commercial Magnafloc 1011 (Percol 727) polymer and in-house synthesised Al-PAM polymer were used to flocculate oil sands tailings that were derived from low and high fines oil sands ores. Fines are defined as mineral solids less than 44 m. The performance of polymers was evaluated in terms of tailings settling, filtration rate, and final moisture content of tilter cakes. Both polymers were shown to effectively flocculate the derived oil sands tailings and hence to enhance tailings settling. Al-PAM performed very well as a filtration aid. The final moisture content of the filter cake obtained from tailings derived from the low fines ore was 6.6 ± 1.2 wt.% and that from the high fines ore was 16.9 ± 0.8 wt.%. This class of polymer can provide an alternative approach for oil sands tailings disposal that has the potential to eliminate tailings ponds. However, the commercial Magnafloc 1011 polymer was found ineffective as a filtration aid for the two tailings tested in this study.Le polymère commercial Magnafloc 1011 (Percol 727) et un polymère synthétiséà l'interne Al-PAM ontété utilisés pour floculer des résidus de sables bitumineux dérivés de minerais de sables bitumineuxà hautes et faibles concentrations de matériaux fins. Les matériaux fins sont définis comme des solides minéraux de moins de 44 m. Le rendement des polymères aétéévalué en termes de la décantation des résidus, du taux de filtration et du contenu final en humidité des gâteaux des réservoirsà basculement. Les deux polymères ont démontré leur capacité a floculer efficacement les résidus de sables bitumineux dérivés et doncà améliorer la décantation des résidus. Le polymère Al-PAM a produit de très bons résultats comme aide de filtration. Le contenu final en humidité du gâteau de filtre obtenuà partir des résidus dérivés du mineraì a faible concentration de matériaux finsétait de 6,6 ± 1,2 en % de poids et de 16,9 ± 0,8 pour le mineraià forte concentration de matériaux. Cette catégorie de polymères peut offrir une approche alternative pour la mise au rebut des résidus de sables bitumineux, alternative qui aurait le potentiel d'éliminer les bassins de décantation de résidus. Cependant, le polymère commercial Magnafloc s'est prouvé inefficace comme aide de filtration pour les deux résidus testés dans cetteétude.

Water Soluble Polymer Flocculants: Synthesis, Characterization, and Performance Assessment

“…The above data was obtained from the filtration of oil sands tailings treated with different flocculants. Reproduced with permission . Copyright 2010, John Wiley & Sons.…”

Current state of fine mineral tailings treatment: A critical review on theory and practice

“…To effectively filter fines-rich feed, either: a) cake thickness must be controlled and minimized (Lockhart & Veal, 1996), or b) particles will need to be coagulated and/or flocculated to promote their effective size and reduce resistance to filtration. The latter approach has seen an increasing number of experimental work and applications in treating fine coal tailings (Alam, et al, 2011), red mud , and oil sand tailings (Xu, et al, 2008;Alamgir, et al, 2012;Wang, et al, 2010), although polymer dosage control is critical for final cake moisture when flocculants are used (Lockhart & Veal, 1996). Surfactants can also be applied at proper dosages to render the particles hydrophobic and hence increase the recession rate of water from the filter cake (Stroh & Stahl, 1990;Morey, 2013).…”

“…As a result, large filtration areas are required to accommodate high-rate processing plants. Laboratory investigations on the pressure filtration of oil sands MFT revealed that higher throughputs can be achieved by proper fine solids flocculation and the selection of a two-stage filtration process (Wang, et al, 2010;Alamgir, et al, 2012). Figure 7 compares single stage filtration (plain region) and two-stage filtration (i.e.…”

“…Permission pending. Product visual of Al-PAM flocs adopted from Wang, et al (2010). Permission pending.…”

Impact of ozonation on particle aggregation in mature fine tailings

“…Many efforts involving physical, chemical, and biological means have been made to consolidate and enable the reclamation of fluid from tailings (Li et al, 2003;Matthews et al, 2002;Mpofu et al, 2004;Proskin et al, 2010;Sworska et al, 2000;Wang et al, 2010). However, the present technologies are environmentally unfriendly or economically unfeasible.…”