Superconducting Coil Layout for High-Gradient Magnetic Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetic density separation systems using permanent magnets are limited by their pole size and strength, which restricts the separation resolution and requires a more concentrated ferrofluid, increasing costs and energy consumption.
Innovation Solution
A unidirectional magnetic field gradient apparatus with a current distribution alternating between opposite directions, utilizing superconducting coils arranged in a specific configuration to generate a magnetic field with a gradient perpendicular to a plane, achieving a strong decay in the vertical direction while maintaining a constant gradient in the horizontal plane, allowing for enhanced separation resolution and reduced ferrofluid concentration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If permanent magnets in the form of Halbach arrays are used, then the magnetic field gradient can be generated for magnetic density separation, but the pole size and strength are limited, restricting separation resolution
Solution Approach 1:
The patent changes the fundamental parameters of the magnetic field generation system by replacing permanent magnets with superconducting coils. This enables generation of much stronger magnetic fields (higher strength parameter) while achieving better field gradient control (improved separation resolution). The superconducting material allows current densities that produce magnetic fields orders of magnitude stronger than permanent magnets.
Solution Approach 2:
The patent substitutes the mechanical permanent magnet system with an electromagnetic system using superconducting coils. This replacement allows dynamic control of the magnetic field through current adjustment, enabling optimization of both field strength and gradient for enhanced separation resolution while overcoming the inherent limitations of permanent magnet pole size and strength.
2Measurement precision
If permanent magnets with limited pole size are used, then the system structure is simpler, but separation resolution is restricted and requires more concentrated ferrofluid, increasing costs
Solution Approach 1:
By changing to superconducting coils, the patent achieves stronger and more controllable magnetic fields that improve separation resolution. This eliminates the need to increase ferrofluid concentration to compensate for weaker magnetic fields, thereby reducing the quantity and cost of ferrofluid required while achieving better separation performance.
3Measurement precision
If superconducting coils are used to generate stronger magnetic fields, then separation resolution is enhanced, but the device complexity increases
Solution Approach 1:
The patent accepts increased device complexity as a necessary trade-off to achieve the desired enhancement in separation resolution. The superconducting coil system, while more complex than permanent magnets, provides superior magnetic field strength and gradient control that directly enables enhanced separation resolution and reduced ferrofluid requirements.
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 apparatus provides improved separation resolution and reduced operational costs by generating a magnetic field with a strong decay in the vertical direction, enabling the separation of particles with higher density and lower ferrofluid concentration, thus enhancing the efficiency and cost-effectiveness of magnetic density separation.
Implementation Method 1
the magnetic field is obtained by having a current distribution of a current in the first plane with a current direction of the current distribution alternating between opposite directions parallel to the second axis with a period λ along the first axis
Implementation Method 2
each leg section comprises a conductor comprising a material having superconducting properties at an operating temperature
Implementation Method 3
The fluid, consisting of a carrier liquid (usually water) with a concentration of ferromagnetic nano-particles dissolved in it, is magnetized by a magnet system that generates a vertical magnetic field gradient. The net force on the feed particles pushes them to an equilibrium height that depends on the mass density of the particle
Data Source
AI summary
The invention relates to a magnet apparatus for generating a magnetic field, the magnet apparatus comprising: at least three coils arranged besides each other along a first axis in a first plane, wherein each coil comprises a conductor comprising a material having superconducting properties at an operating temperature, the coils further comprise two legs and two bent end sections in the first plane, wherein a first and a second leg are arranged parallel to each other along a second axis in the first plane transverse to the first axis, and the two bent sections are arranged opposite to each other; and a controller arranged to control currents through the respective coils to obtain a current distribution in the first plane, wherein a current direction of the current distribution is alternating between opposite directions parallel to the second axis, with a period λ along the first axis. The invention also related to a magnetic density separation apparatus comprising the magnet apparatus.