19 Feb 2021

Blog Bite 1: Geotube® Systems Come of Age for Mining and Mineral Process Waste Dewatering

By John Smith


Welcome to our blog space where we share our insights and experiences in civil engineering and geosynthetics. We feature bite-sized articles for quick and easy consumption

                                                                                                                                                                                                                                                                                    

Over recent years there has been a noticeable increase in the use of TenCate Geotube® systems in dewatering mineral waste or being part of mine water and waste stream management practice.

So, what is driving this increased acceptance and how successful are Geotube® systems in dewatering complex slurries? We explore 4 key reasons in 4 bite-sized pieces.

Let’s have our first bite where we explore advances in capacity of TenCate Geotube® dewatering systems.

#1. HIGH VOLUME CAPACITY

Tradition = Perception

Geotube® systems have traditionally been limited to the dewatering of relatively small-to-medium sized volumes of mineral, industrial and agricultural waste slurries where the capital cost of installing conventional mechanical dewatering equipment is considered high for the volume of waste to be treated. This resulted in the perception that geotextile tubes are not suitable for high volume applications.

Large-scale dewatering project

Large-scale dewatering project

Market Dynamics

One of the reasons for this narrow use of geotextile tubes relates to local market dynamics. Where dewatering of small waste volumes is mostly driven by local specialist applicators who offer a dredging, pumping, polymer make-down unit (PMU) and disposal package to the asset owner. Many of these applicators source the lowest cost stock geotextile tubes from manufacturers and their distributors without properly comparing tube dry cake capacity or undertaking any real assessment of the slurry and alternative geotextile tube options that could significantly increase productivity and reduce cost.

Dredging silt sediments

What is Viable?

This approach is viable for small volumes of slurry but it is not viable for high volume slurry dewatering which requires a more sophisticated engineered approach and much larger geotextile tubes with substantially higher solids retention capability.

Solutions for Every Project

TenCate has the ability to manufacture super-large Geotube® units with dry cake capacities exceeding  3,000m3 per unit that can be stacked in layers has opened up possibilities for use in applications where previously geotextile tubes would not have been considered.

By assessing the demands of each project as a unique case, TenCate can offer project specific geotextile tube dimensions to accommodate substantially higher slurry flows and solid retention whilst using a smaller footprint and utilizing the same manpower as required for small waste volumes.

So Much to Gain

One example where large capacity geotextile tubes have stimulated thinking is in the re-processing of old mineral rich tailings which would normally require construction of new or expanded Tailing Storage Facility (TSF) cells to contain the reprocessed slurry.

Given that efficiently dewatered Geotube® systems reduce volume footprint, the use of large capacity geotextile tubes placed within the boundary of the old excavated TSF can eliminate or delay TSF expansion and simplify end-of-life closure complexity whilst generating a positive net return.

This concept is very attractive for mineral extraction when ore concentrations or prices are low.


Dewatering Geotube® units deployed 


That’s all for now on. Stay tuned for the second bite-sized piece where we look at the “Application Versatility of TenCate Geotube® Dewatering”.

TenCate Geosynthetics Asia
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