Separation Process of Fine Coals by Ultrasonic Vibration Gas-Solid Fluidized Bed

Area of Science:

• Mineral Processing
• Chemical Engineering
• Materials Science

Background:

• Fine coal separation is crucial for efficient energy utilization and environmental protection.
• Traditional methods face challenges in effectively separating fine coal particles based on density.
• Ultrasonic vibration technology offers a novel approach to enhance separation efficiency.

Purpose of the Study:

• To investigate the application of ultrasonic vibration gas-solid fluidized beds for fine coal separation.
• To evaluate the impact of ultrasonic vibration on density-based particle separation.
• To analyze the composition and characteristics of the separated heavy products.

Main Methods:

• Development and implementation of an ultrasonic vibration gas-solid fluidized bed.
• Utilizing analytical techniques including X-ray Fluorescence (XRF), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and Electron Probe Microanalysis (EPMA).
• Characterization of heavy product composition, including elemental, phase, and surface analysis.

Main Results:

• Ultrasonic vibration significantly enhances density-based particle separation at 35 kHz and a fluidization number of 1.8.
• Maximum ash difference (47.30%) and combustible recovery (89.59%) were achieved.
• Heavy products showed enrichment in pyrite sulfur (up to 6.78%), pyrite, quartz, kaolinite, and harmful elements like F, Pb, and As.

Conclusions:

• Ultrasonic vibration gas-solid fluidized bed technology is effective for fine coal separation.
• The process preferentially concentrates high-density minerals and harmful elements in the heavy fraction.
• This technology holds promise for improving coal cleaning and potentially mitigating environmental impacts.