An Experimental on Filtration and Clogging of Geotextile Filters around Drain Pipes in Fine Tailings

• Published in: KSCE journal of civil engineering Vol. 28; no. 5; pp. 1767 - 1776
• Main Authors: Li, Dong-dong, Cui, Xuan, Huang, Jing-qi, Han, Ya-bing
• Format: Journal Article
• Language: English
• Published: Seoul Korean Society of Civil Engineers 01.05.2024; Springer Nature B.V; 대한토목학회
• Subjects: Backwash; Civil Engineering; Cleaning; Drainage; Drainage systems; Electron microscopy; Engineering; Filter cake; Filters; Filtration; Fluid filters; Geotechnical Engineering; Geotechnical Engineering & Applied Earth Sciences; Geotechnical fabrics; Hydraulics; Hydrostatic pressure; Industrial Pollution Prevention; Microscopic analysis; Mine drainage; Mine tailings; Particle decay; Particle size distribution; Permeability; Pipes; Pore pressure; Pore water; Pore water pressure; Radial flow; Scanning electron microscopy; Seepage; Size distribution; Water pollution; Water pressure; 토목공학; Needle-punched geotextiles; Radial flow tests; Clogging mechanism; Backwash; Fine tailings; Filtration behaviour
• ISSN: 1226-7988; 1976-3808
• DOI: 10.1007/s12205-024-1292-0

Needle-punched nonwoven geotextiles have been used as filters for decades in mine drainage systems. But the physical clogging of geotextiles by fine particles has continued to receive increasing attention. In this study, the permeation characteristics of a drain pipe wrapped with geotextiles were investigated based on a new radial flow experiment apparatus, and particle size distribution (PSD), pore water pressure (PWP), and scanning electron microscopy (SEM) analyses were employed to identify the geotextile clogging mechanism. The geotextile cleaning methods after clogging were also discussed. The results showed that an exponential decay of hydraulic conductivity (K) with time under different flow conditions. Particles less than 30 μm migrated to the drainage pipe under the action of seepage forces, and a dense and thick cake layer was formed upstream of the geotextile filter. According to microscopic analysis, the clogging process of geotextiles was divided into three stages: pore blockage and cake formation, filter cake dynamic growth and cake layer filtration. Backwash cleaning is a good way to remove a filter cake layer on the surface of geotextiles, which can recover 60% of the hydraulic conductivity (K 0 ).