Effect of Weathering on Surface Characteristics of Solids and Bitumen from Oil Sands

Abstract

The effect of weathering on the surface chemical composition and wettability of the oil sand solids and bitumen was studied by contact angle measurement, film flotation technique, XPS analysis, and ellipsometry thickness measurement. It was found that mild bitumen oxidation occurred during ore weathering. However, it has negligible effect on the bitumen surface wettability. In contrast, weathering forced more organic matters to adsorb onto the mineral solid surfaces, which made the solids more hydrophobic. A mechanism on how the organic matters adsorb on the solid surface due to weathering was put forward. The loss of the formation water due to weathering resulted in an intimate contact of bitumen with the mineral solids and thus offered the opportunity for the organic matters to adsorb, which was responsible for the enrichment of organic matters on the mineral solid surface. It was further observed that hot water washing partially removed the organic matters from the solids surface and hence decreased the solids hydrophobicity.

Application of microbial enhanced oil recovery technology in water‐based bitumen extraction from weathered oil sands

“…Extra deionized water was added to the cell to meet the requirement of 900 mL. 11 Then, the extraction processes was conducted at 60 C under mechanical agitation at 1500 rpm for 5 min. After conditioning, air was introduced at a flow rate of 150 mL/min and the bitumen froth was collected as a function of time for a total of 15 min.…”

“…Weathered oil sands is referred to as ore that has been exposed to external environment for an extended period e of time and/or is not deeply buried under the overburden. 11 The effect of weathering on oil sands processability has been reported recently. 9,[12][13][14][15][16] By studying a laboratory weathered ore and a naturally weathered ore, a mechanism on the deteriorated processability of oil sands due to weathering was proposed by Masliyah and coworkers.…”

“…9,[12][13][14][15][16] By studying a laboratory weathered ore and a naturally weathered ore, a mechanism on the deteriorated processability of oil sands due to weathering was proposed by Masliyah and coworkers. 11,13 It was suggested that the formation water loss because of weathering led to a close contact of bitumen with the solids surface and hence resulted in the adsorption of organic matter. The increased hydrophobicity of the solids Correspondence concerning this article should be addressed to S. Ren at slren@licp.cas.cn.…”

“…9,11,13 The important reason leading to these problems is that the hydrophobic characteristic of the solid sands or the high bitumen viscosity. 11,28 However, as far as we know, there is no one effective method yet to solve the poor processability of the weathered oil sands.…”

“…9,11,13 The important reason leading to these problems is that the hydrophobic characteristic of the solid sands or the high bitumen viscosity. 11,28 However, as far as we know, there is no one effective method yet to solve the poor processability of the weathered oil sands. Considering that the MEOR processes could produce biosurfactants to alter the solids wettabiltiy and degrade the heavy component of oil to reduce the oil viscosity, the MEOR technique was first proposed to be applied in the water-based bitumen extraction from weathered ores.…”