Filament Geotextile for Mining Drainage and Tailings Storage Facilities

Filtration

Filtration is one of the most important functions in tailings drainage. The geotextile allows water to pass through while limiting the migration of unwanted fine particles into the drainage layer. A filter should not simply block all soil particles. The objective is to achieve a suitable balance between water flow and particle retention.

Separation

In mine roads and stockpile areas, geotextiles can separate weak subgrade soil from gravel. This reduces intermixing between different soil layers under construction and traffic loads.

Drainage Assistance

Nonwoven geotextiles allow water to pass through their pore structure. However, they should not be considered a direct replacement for drainage pipes or granular drainage layers. The geotextile mainly provides filtration and interface drainage, while the drainage layer carries the larger volume of water.

Geomembrane Protection

Where HDPE geomembranes are used for containment, a nonwoven geotextile may be incorporated as a protection layer to reduce the risk of mechanical damage.

Filament nonwoven geotextiles can be used in mining tailings dams, tailings drying areas, and mine drainage systems for filtration, drainage, and soil separation. For iron ore tailings containing a high proportion of fine particles, geotextile selection should not be based only on mass per unit area such as 200, 400, or 600 g/m². The design should also consider thickness, filtration opening size, permeability, tailings particle-size distribution, fines content, and long-term clogging behavior.

For similar mining projects, NUOKUN’s selection approach is to evaluate the tailings material and hydraulic conditions first, and then determine the geotextile mass, thickness, filtration opening, and permeability, rather than selecting the product only to meet price per square meter.

Q1. Is 400 g/m² geotextile suitable for a tailings dam?

It may be suitable for certain projects, but it should not be treated as a universal specification. The Germano research included 400 g/m² continuous-filament polyester nonwoven geotextile, but the appropriate specification depends on the actual project conditions. 

Q2. Can geotextile filters clog?

Yes. Fine particles may accumulate within or on the surface of a geotextile under certain long-term hydraulic conditions.

A 2024 experimental study of geotextile filters around drain pipes in fine tailings also observed hydraulic conductivity reduction over time and the development of filter cake layers. 

Q3. Can geotextile be used together with HDPE geomembrane?

Yes. HDPE geomembrane is mainly used for containment, while geotextile can provide protection, filtration or separation depending on the system design.

Q4. Should a mining project use PP or PET geotextile?

Both materials can be used in geotechnical applications. The appropriate choice depends on the required mechanical properties, durability requirements, environmental conditions and project specifications.