Application of Polymers in Oil Sands Tailing Ponds

(Suncor Energy 2010)

Kenneth OkonkwoDepartment of Chemical and Material Engineering

University of Alberta

(Suncor Energy 2010)

Overview

BackgroundObjectivesConclusion

Formation:Bitumen hot water extraction process produce tailings:

Coarse particles ( settles quickly )(sand) Residual bitumen Water Fine particles ( suspended in water but settles slowly) (clay )

- Result into to stable suspension in water know as mature fine tailings (MFTs)- Left on its own, the MFTs could take centuries to solidify (Suncor, 2010)- Characteristics of MFTs *

30 wt% solid( 97 wt% fine and less than 44µm size ) 3 wt% hydrocarbons 65 wt% water

Problem:Long-term storage of the MFTs is costly and poses a major environmental liability.

Solution:How to accelerate consolidation of MFTs

*A. Alamgir et.al. Oil Sands Tailings Research Facility (2010 ) 6- 8

Highlights: Oil Sands Tailing Ponds

(Alberta Environment's Information Centre, 2009)

Oil Sands Tailing Ponds - strata

OBJECTIVES

Understanding the application of polymers in in oil sands tailing ponds

Properties of polymersPresent the effect of tailing characteristics on

polymer performance

MFT drying Consolidated Tailing Technology( CTM of Suncor Energy )Tailings Reduction Operations( TROTM of Suncor Energy )Polymers PolymersAnionic commercial polyacrylamide (PAM)An Al(OH)3-PAM hybrid polymer (Al-PAM) synthesized in lab;Non-ionic Poly (N-isopropyl acrylamide) (PNIPAM)

Applicable Solutions

Polyacrylamide N-isopropylacrylamide

Application of Polymers

H. Li et.al, International Oil Sands Tailings Conference Edmonton(2008) 4

Polymers- properties

The flocculation of fine suspensions depends on a number of factors which include:

Type Molecular weight Ionization degree of the flocculants Mineralogical composition Particle size of solid particles pH and chemical composition of the solutions Hydrodynamic conditions

Polymeric flocculantsProperties Al-PAM Magnafloc 1011

Structure Al(OH)3-PAM Acrylamide-Acrylate co-polymer

Molecular weight (Da) 2.0x106 17.5x106

Type Cationic Anionic

A. Alamgir et.al. Oil Sands Tailings Research Facility (2010 ) 6- 8

Comparison of the settling of the laboratory extraction tailings withthe addition of Al-PAM and Magnafloc 1011 (a) low fine tailings (b)high fine tailings

Xiaoyan Wang et.al. Oil Sands Tailings Research Facility ( 2010 )79- 80

(a) Low Fine Tailings (b) High Fine Tailings

Conclusion

Polymers can provide alternatives for oil sands tailings handling

THANK YOU