High-throughput processing of microplastics based on Z-type radial flow separator: Fluid flow characteristics.

Area of Science:

• Environmental Engineering
• Water Treatment Technologies
• Separation Science

Background:

• Traditional axial flow rapid sand filters face limitations like small filtration area and high pressure drop.
• Instability in high-throughput flow hinders the efficiency of conventional filtration methods for microplastic removal.

Purpose of the Study:

• To develop and evaluate an innovative Z-type radial flow separator (ZRS) for enhanced microplastic separation.
• To address the limitations of traditional filters by improving flow dynamics and separation performance.

Main Methods:

• Developed a Z-type radial flow separator (ZRS) with a guide cone structure to modify flow fields.
• Utilized activated alumina for adsorption and synergized it with a radial-spiral composite flow state.
• Conducted pilot experiments at a flow rate of 5 m³/h to assess performance.

Main Results:

• The Type-D ZRS configuration showed a 62.4% lower maximum pressure drop amplitude and reduced MPs distribution inhomogeneity by 63.1% compared to Type-A.
• Separation efficiencies for microplastics (MPs) below and above 10 μm were 87.65% and 86.4%, respectively, outperforming the axial flow mode.
• Stable rejection of 1-20 μm MPs was achieved across a wide concentration range (10-200 mg/L), with 92-96% removal efficiency at low concentrations (10-20 mg/L).

Conclusions:

• The ZRS demonstrates significant potential for high-throughput and deep separation of microplastics.
• The device offers improved pressure drop characteristics and more uniform MPs distribution.
• ZRS shows substantial promise for application in the tertiary treatment stage of wastewater treatment plants.