With a proud history spanning 200 years, Valmet has perfected its high-quality filter fabric solutions over many years.
Long term co-operation with suppliers, customers, universities and research institutes has cemented the company as one of the world’s leading suppliers of filter fabrics.
Coupled with extensive in-house R&D as well as the wealth of expertise and manufacturing facilities that comes with a global company, it has meant Valmet has remained at the forefront of innovation.
This vast experience extends to the high-level solutions that Valmet supplies to the mining industry for all applications, from disc, drum and press filter fabrics to tower press, belt filters and linear screens.
Its fabrics are developed to withstand high process temperatures, complex chemical environments, and a wide variety of slurries.
Australian Mining Review spoke to Valmet’s ANZ Filtration Product Manager Mike Murphy about how the company’s smart cloth technology is enhancing chemical and mining filtration processes by increasing productivity and delivering savings.
Smart Cloth Monitoring System
The process of filtration or dewatering involves a slurry coming up against a cloth, which is an integral part of any filter.
As the water from the slurry passes through the cloth, the “dirt” or ‘’cake’’ which is the tailings, metal concentrates or industrial minerals, is captured by the cloth.
Valmet provides the interface that allows this separation of the liquids from the solids.
It is important to note the company does not build filters but rather supplies the cloth that goes into filter.
Valmet’s cloths can be equipped with smart cloth technology.
Michael said a filtration operation can consist of several filter presses and consume thousands of filter cloths every year.
“Getting accurate analytical information about cloth lifetime, the reasons for cloth removal, failure modes and cloth consumption, allows the entire filtration process to be improved,” he said.
Valmet has developed a world-first Industrial Internet application, based on a program used to gather and analyse data to provide informative visual reports.
This allows continuous improvement of the filter cloth and the process to get the most out of a filtration operation and minimises the need for shutdowns.
Operators access an easy-to-use tablet interface to load data during cloth installation and removal.
An online reporting portal provides real time concise data to stakeholders, such as early-stage plate damage and failure patterns to enable quick improvements.
Information gathered about cloth performance provides a valuable tool for operators about the performance of filters and can be projected onto other process parameters.
The benefits of using the system are:
- Increased production
- Reduced OH&S risks from fewer cloth changes
- Savings through planned maintenance
- Reduced filter downtime
- Optimised filter cloth performance
- Remote filter cloth technology support
- Better control over the filtration process
“This reporting and analysing system allows end-users to analyse cloth use and how they might optimise their machine and their processes around that usage,” Michael said.
“It is not something our competitors are doing that we are aware of, so it is very unique.”
Case Study
Valmet supplies filter fabrics with smart cloth technology to Karara Mining, which is the largest mining operation and the first major magnetite mine in Australia’s Midwest region.
The delivery includes filter fabrics for 11 chamber press filters for concentrate and tailings de-watering.
Karara hand-picked Valmet to meet objectives for increased cloth life, improved machine availability and, ultimately, to boost production with new technology.
At the beginning of 2020, Karara devised a pilot project to identify a supplier who could provide world class filter fabrics with technical support and Valmet’s products stood out with excellent results.
Karara Production Coordinator Gavin Kelly said the company was always seeking innovative and world class technology, and for that reason organised a pilot project to select the cloth with best performance.
“The average life of Valmet cloths is approximately 5500 cycles whereas the current supplier’s is about 1500 cycles, which brings tangible benefits to our operation,” he said.
Michael said extensive site trials provided the customer with valuable data insight regarding the technical and commercial benefits.
Tailored Solutions
The right choice of filter fabrics makes a huge difference in today’s chemical and mining industry processes.
The demands on materials are tough and fabrics may have to endure high temperatures and difficult chemical environments for prolonged periods.
They must be able to filter different slurries and various particle sizes and, in addition to all of this, they must deliver a clear filtrate, have excellent cake release and a dry cake.
All of Valmet’s fabrics are engineered to suit specific applications, based on extensive testing and a thorough knowledge of the required outcomes.
Fabrics can be made from a wide variety of raw materials including polypropylene, polyethylene, polyamides, nylon and polyester.
“The raw material is based on the process parameters, which might be the temperatures the slurry or the machine is operating at and what kind of chemicals are involved,” Michael said.
“For instance, the use of raw materials at an alumina refinery would be limited due to the corrosive nature of the product.
“Even if you had two mines both handling magnetite, you could never assume the same cloth will work at both, nothing can be further from the truth, you have to engineer each one.
“You have to carefully consider the weave type so for sticky clays, polypropylene might not be suitable so you might use polyester.
“Then you need to start drilling down into what the permeability and robustness needs to be.
“Some machines are much harsher on cloths than others— for instance, a disc filter may not wear the cloth very much but something like a chamber press may do.”
Valmet’s fabrics are engineered to meet the customer’s requirement, down to the smallest detail, to provide customers with the best possible filtration results, both technically and economically.
Valmet’s ability to offer such an extensive product range of tailored solutions and technical support through its highly trained product managers make them the go-to partner for the world’s leading mining and chemical companies for their filter cloth needs.
Research And Development
Through a world-class facility in Portugal, Valmet’s extensive in-house R&D allows it to stay one step ahead of other fabric manufacturers.
Laboratory analysis of raw materials and finished goods allows the company to devise custom made solutions in collaboration with customers, universities, research institutes and suppliers.
Capabilities include research facilities for used fabrics, chemical analysis and wear studies for fabrics, filters and dewatering equipment.
Mike said Valmet will often run large scale trials to ensure all client criteria are met.
This can include cake moisture content, filtrate clarity, and solids retention.
As filter cloth is a consumable, Total Cost of Ownership (TCO) must be determined to understand the real cost.
“The longer the cloth lasts, the lower the cost of ownership.
“Valmet cloths may be slightly more expensive than a competitors, however, if ours last three times longer, then we are actually cheaper.
“The work that goes into making a new cloth is extensive, it is very much a niche industry and there aren’t many companies around who can do this on a large scale.”
Mining Applications
Valmet continues to be the world’s leading developer and producer of filter fabrics for the mining and chemical industries.
Its range of filter fabrics is the most extensive on the market and includes tower press filters, belt filters, press filters, horizontal vacuum belt filters, drum filters, Kelly filters and vacuum disc filters.
Following the dam collapses in Brazil, Valmet is leading the global movement to de-water tailings.
Robust Valmet Tower Press Filter Fabrics execute most of the work at the heart of the tower press, producing clear filtrate and cake with a low moisture content.
The fabrics result in significant cost savings in filter cloths as well as enhanced productivity thanks to more durable cloth, and higher filter availability.
Many of the leading mining companies and disc filter manufacturers use Valmet’s disc filter fabrics and services.
With easy installation and a perfect fit, Valmet’s plastic sectors, disc filter bags, and easy fix caulking rubbers provide high capacity and durable filtration solutions.
Valmet offers high-quality press filter fabrics for vertical plate pressure filters (VPA) for filtration of metal concentrates, industrial minerals and tailings, and for filters in fast-opening filter presses (FFP) for bulk mining.
Valmet has a range of belt filter fabrics for horizontal vacuum belt filters, belt press filters, linear screens and conveyor belt applications to improve dryness, enable faster speeds and reduce energy consumption.
The range offers a solution for any filtered particle size, including dense multifilament fabrics, needled felts, double layer weave and mesh horizontal vacuum belt filter fabrics.
History
Valmet’s experience in chemical and mining filtration spans more than 50 years, but the history of the company extends all the way back to 1797 when it started manufacturing traditional textiles in Finland.
The mill started making felts for papermaking in 1882 and then moved into filter fabric manufacturing in 1965.
The company name has changed several times through the years (Verkatehdas, Tamfelt, Metso, Valmet) but the commitment to quality and level of expertise has endured.
Long term relationships with customers built on trust and close cooperation with the world’s leading filter manufacturers are the key to the company’s longevity.
Original Tamfelt filter fabrics are still part of Valmet’s product offering.
Headquartered in Finland, Valmet is known as the leading global developer of process technologies, automation and services for the pulp, paper and energy industries.
But it is now carving out an equally solid reputation in the niche industry of filter fabric solutions to improve processes and lift productivity at major Australian mine sites.
SOURCE
Valmet
P 0436 100 033
E [email protected]
W www.valmet.com/en-AU/products–services/mining/filtration-facbrics/