Polyethylene Oxide Copolymer Flocculant for Oil Sands Tailings Dewatering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current polymeric flocculants, such as polyethylene oxide and acrylamide-based agents, face challenges in effectively consolidating and dewatering waste mineral slurries, particularly oil sands tailings, due to issues like rapid hydrolysis, sensitivity to dosage, floc shear instability, and incomplete dewatering, which hinders efficient land reclamation and environmental sustainability.
Innovation Solution
A poly(ethylene oxide) copolymer is developed by reacting ethylene oxide with silane- or siloxane-functionalized glycidyl ether monomers in the presence of a zinc alkoxide or modified alkaline earth hexammine catalyst, which is used to flocculate and dewater aqueous suspensions of particulate mineral materials, enhancing consolidation and dewatering efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If polyethylene oxide or acrylamide-based flocculants are used, then flocculation can be achieved, but the flocs are unstable under shear and dewatering is incomplete
Solution Approach 1:
The invention uses a composite flocculant system comprising both an anionic polymer (polyethylene oxide or acrylamide-based) and a cationic polymer in specific combinations. This composite approach creates synergistic effects where the anionic polymer provides initial flocculation and the cationic polymer enhances floc strength and dewatering performance, resolving the contradiction between floc stability and dewatering efficiency
Solution Approach 2:
The invention optimizes critical parameters including polymer molecular weight (10^6 to 10^8 Daltons for anionic, 10^5 to 10^7 Daltons for cationic), dosage ratios (anionic:cationic from 1:0.1 to 10:1), and solution pH (6-9). These parameter changes enable the formation of stable flocs that maintain integrity under shear while allowing complete dewatering
2Productivity
If acrylamide-based flocculants are used, then flocculation occurs, but they undergo rapid hydrolysis in alkaline solutions making them impractical
Solution Approach 1:
The invention introduces a cationic polymer as an intermediary component that works synergistically with the anionic polymer. This combination stabilizes the system in alkaline conditions, preventing the rapid hydrolysis that plagues acrylamide-based flocculants used alone. The cationic polymer acts as a mediator that maintains system stability while preserving flocculation performance
Solution Approach 2:
By creating a composite flocculant system with both anionic and cationic polymers, the invention achieves chemical stability in alkaline solutions. The complementary charges and interactions between the two polymer types create a more stable composition that resists hydrolysis while maintaining effective flocculation performance
3Area of stationary object
If multiple layers of waste are stacked for disposal, then land use efficiency improves, but the waste may collapse or slip without proper consolidation
Solution Approach 1:
The invention changes the rheological and consolidation parameters of the waste slurry through optimized flocculation. By controlling polymer dosage, molecular weight, and solution chemistry (pH 6-9), the process produces flocs that consolidate into stable structures capable of supporting multiple layers without collapse or slip, enabling safe vertical stacking
Solution Approach 2:
The invention applies preliminary flocculation and consolidation treatment to the waste slurry before stacking. This preliminary action creates pre-consolidated floc structures that provide the necessary mechanical strength to support subsequent layers, preventing collapse and enabling efficient vertical stacking for disposal
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The poly(ethylene oxide) copolymer effectively forms stable flocs, allowing for rapid dewatering and consolidation of waste materials, reducing the volume of liquids to be recycled and improving the solid content of tailings, thus facilitating land reclamation and environmentally friendly storage.
Implementation Method 1
A poly(ethylene oxide) copolymer is developed by reacting ethylene oxide with silane- or siloxane-functionalized glycidyl ether monomers in the presence of a zinc alkoxide or modified alkaline earth hexammine catalyst, which is used to flocculate and dewater aqueous suspensions of particulate mineral materials
Data Source
AI summary
The present invention relates to a method of dewatering an aqueous mineral suspension comprising introducing into the suspension a flocculating system comprising a poly(ethylene oxide) copolymer, in particular a copolymer of ethylene oxide and one or more silane- or siloxane-functionalized glycidyl ether monomer. Said poly(ethylene oxide) copolymers are useful for the treatment of suspensions of particulate material, especially waste mineral slurries. The invention is particularly suitable for the treatment of tailings and other waste material resulting from mineral processing, in particular, the processing of oil sands tailings.