Select Page

Mechanical Dewatering of Mine Tailings


As the mining industry is currently being challenged to construct fewer tailings dams by replacing conventional tailings production with dewatered tailings technologies, the goal of this project is to research existing technologies that remove excess moisture from tailings waste and in turn, strengthen their shear capacity. As a whole, this project is focused on technologies that allow for dry stacking of tailings, thus removing the need for conventional tailings dams. As the primary goal of this project is to examine and improve upon tailing dewatering systems for large scale mines, the work performed this semester was focused on research and analysis of existing dewatering technologies. As there are many different mine types with different tailings characteristics and site-specific throughputs, this project required the team to take into account the wide range of expected throughputs at different Newmont sites. Daily throughput is often a major limiting factor for dewatering technologies, so great consideration was taken by the team to examine the daily expected capability for the technologies examined. For research and cost analysis, four Newmont mines currently implementing dewatering technologies were examined. The table below summarizes the different technologies each mine is currently implementing. GeoWaste/EcoTails is a newer technology being developed by Newmont to “create an economical and environmentally sustainable solution to tailing in large scale operations by optimizing water re-use and producing a stable GeoWaste”. This system is designed for large-scale fast filtering and will be one of the three technologies examined by this team, but it is not currently being implemented at any Newmont sites.


Mine Name

Mine Location

Filtration Method

Daily Throughput (mtpd)


Quebec, Canada

Filter Press



Northern Territory, Australia

Vacuum Filter



Zacatecas, Mexico

Testing Geowaste/EcoTails



San Miguel, Guatemala

Filter Press


Live Zoom Chat

Use the link below to join us live from 8:00 – 10:30 a.m. on December 3.

Please use passcode: 734735

Or iPhone one-tap: 12532158782,92831700720# or 13462487799,92831700720#

Or Telephone:
Dial: +1 253 215 8782 (US Toll) or +1 346 248 7799 (US Toll)

Meeting ID: 928 3170 0720

Team Members

  • Jarod Horton
  • Brian Schreffler
  • Ryan Espinoza
  • Austin Gates

The Client

  • Newmont Corporation



Project Advisor: Robin Bullock

Newmont Lead: Kim Morrison 

Newmont Technical Advisor: Brett Byler 

Newmont Technical Advisor: Manuel Aparicio



Elevator Pitch


With the increase in the frequency and severity of conventional tailing storage facility (TSF) failures, the mining industry as a whole is in search of alternative tailings handling and storage methods capable of mitigating or eliminating both the risks and the costs associated with conventual TSF and TSF failure. Newmont tasked the team to analyze mechanical dewatering and dry stacking as a potential means to mitigating this risk. The three dewatering methods researched were Filter presses, Vibratory Belt Filters, and Newmont Goldcorp’s developing technology EcoTails/Geowaste. Three key performance indicators were evaluated within each method. These were each method’s achievable moisture content, tailings throughput capacity, and each method’s respective related capital and operational expenditures. Through the utilization of site-specific data provided by Newmont, as well as interviews and articles obtained from various OEM manufacturers, the group was able to evaluate and compare the overall advantages and drawbacks of each type of technology.

It was determined that today’s available filter press technology performs excellently in the achievable water content category, with achievable ranges of ~15-20%. The filter press’s largest drawback was the method’s throughput capabilities, which become unreasonably expensive for operations processing tailings in excess of 10,000 metric tons per day (mtpd). Further development to increase this technologies feasibility on larger throughput sites is currently under development by several manufacturers and will ultimately make filter press technology an extremely viable option in the future. Vibratory Belt Filtering proved to be almost just as capable at dewatering with achievable moisture contents in the range of ~18-20%. The main advantage was the methods throughput handling ability which outperformed the filter press from an overall cost standpoint. The EcoTails/Geowaste technology is extremely new and proprietary to Newmont. The main foreseen advantage of this technology was its ability to process large throughput amounts in the order of ~100,000+ mtpd while maintaining feasible capital and operational expenditures. The technology’s utilization of waste rock was also an appealing characteristic of the method which showed potential to also reduce acid rock drainage specific to problematic tailings.

Design Approach

The design approach for the project was based on researching the three main dewatering technologies identified by Newmont. For filter presses, research was broken down into several sections. Initially, four different manufactures of filter presses were contacted including McLanahan Corporation, M.W. Watermark, Diemme Filtration, and FL Smidth. Each is a company currently manufacturing varying sizes of filter presses, with only Diemme Filtration and FL Smidth producing and improving large-scale presses for mining. Information provided by these companies was compiled and compared with the information provided by Newmont from the Eleonore mine site. After comparing the information provided, research was performed to look into major issues with this technology and areas for improvement currently being pursued in industry.

Vacuum filters, also known as horizontal belt filters, were examined next. This technology is well known in industry so the focus of research was around the information provided by Newmont in relation to the Tanami mine in Australia and the Boddington mine case study. Both of these mines looked into implementing or improving the vacuum belt filter technology, and as they pertained specifically to Newmont, the team decided to focus on compiling and examining the information provided for these sites. The Viper filtration system, currently being implemented at Tanami, was also examined by the team. After compiling and examining the information provided by Newmont, research was performed to look into major issues with this technology and areas for improvement currently being pursued in industry.

The final technology examined is the newest technology being developed by Newmont, GeoWaste/EcoTails. This technology is still in development, so all information compiled was provided directly by Newmont. The research focused on determining how the technology worked and expected major benefits and issues. As this technology is still in development, this research was more theoretical than the other two sections. Major pros and cons are still being discovered as this technology develops, but information on known issues and benefits was compiled by the team.

After examining the different technologies, economic information was compiled for all three dewatering technologies and compared. Each technology excels in different environments and under different conditions, which the team examined in their report. As this project is only in its first semester, the final step was to decide what future steps should be taken to improve upon this project next semester.

Design Solution

          Each system has disadvantages and advantages that make that technology ideal for different environments. For lower throughput mines with finer particle sizes and a desired lower moisture content, current industry designed filter presses should be used. In recent years, filter press manufactures have been working to increase the area of manufactured filter presses, which in turn will increase the daily throughput of each machine by more than 20%. This technology is still in development but could make the filter press technology economically viable for mines with a throughput great than 10,000 tons/day. Vacuum filters are optimal for mines with high daily throughputs, larger grains size, low clay content, and a desired mid-range moisture content. Industry has been developing ways to improve upon the issues with vacuum filters, such as belt speed, by developing technologies like the Viper vibrating filtration system. The Viper system helps decrease the final moisture content and increase the consistency of the final filter cake, improving the overall process for filtering tailings. This technology is limited, however, as it does not perform well with incredibly fine tailings or tailings with high clay content. The newest technology being developed by Newmont, GeoWaste, is being designed to blend filtered tailings with waste rock in transit to create a geotechnically stable product. GeoWaste’s high strength, easily stackable tailings make this option appealing to Newmont, especially in large high production settings such as Newmont’s Penasquito site. Additionally, for mines with a small footprint, this option may be desirable as the final product combines both waste rock and tailings reducing the overall land area required. As this technology has recently been developed, not much is known about areas of issue or total economic feasibility.

When comparing the three separate technologies, no one best technology can be declared without first examine the type of tailings being produced by a mine. At the Eleonore mine in Canada, lower daily throughput and low desired moisture content make filter presses the ideal technology for this mine. The large daily throughput provided by vacuum filters may result in fewer machines required, but the higher final moisture content and smaller particle size distribution would not be ideal for vacuum filters. At the Tanami mine, high daily throughputs of 50,000 tons/day were expected, automatically eliminating filter presses as the CAPEX of buying a large number of filter presses would be economically infeasible. GeoWaste may be a viable option for Tanami due to its high throughput, but higher operating costs may be a detrimental factor. Based on Penasquito’s high fine particle size content, the team would recommend using GeoWaste, which is currently being tested at Penasquito. Finally, at the Marlin mine, high clay, fine particle sizes, and low water content make filter presses the only viable option. In conclusion, determining the optimal technology for a specific mine is highly dependent on the desired final moisture content, particle size, and daily throughput.

Next Steps

Now that an in-depth understanding of three different dewatering technologies has been developed, the work focus can move towards testing and finding areas for improvement. Depending on Newmont’s feedback, the team will start by dewatering tailings using the three dewatering technologies. Using the same batch of tailings with the same tailing’s characteristics, each separate technology will be tested on a small scale to determine which technology optimizes final moisture content, the ability of the produced dried tailings to be stacked, possible expected throughput, and expected area required for storage. After determining which technology has the optimal combination of the metrics described above, testing of the single best-determined technology using several different tailings types with varying tailing characteristics will be performed. By using different tailings types on the same technology, the team hopes to determine the optimal combination of tailing metrics (such as clay, particle size, etc.) which will result in the best-dewatered tailings. In this stage, additional chemical components may be added to see if metrics can be improved. The final work flow for next semester is dependent on feedback and recommendations from Newmont.

Meet the Team

Jarod Horton
My name is Jarod Horton and I’m a first-semester senior civil engineering student here at Mines. My career aspirations lie in and around the construction industry and structural engineering. My hobbies include anything remotely related to the outdoors!


Brian Schreffler

Brian is a senior studying mechanical engineering from Castle Rock, Colorado. Brian managed the budget and compared financial information for the mechanical dewatering project. When not doing school work, Brian spends his time playing soccer, skiing, or hiking depending on the season. After he graduates, Brian is planning to work in the aerospace industry and hopes to one day go to space. 

Ryan Espinoza

I am a Mechanical Engineer for the Fall 2021 Class of School of Mines.
My main task for this project was to research the new mining Filtration option EcoTails.

Austin Gates

Hi, my name is Austin Gates and I am a second-semester senior in mechanical engineering. Upon graduating, I hope to work in either manufacturing or the aerospace industry. In my free time I enjoying reading, watching Netflix, and running.