Bunting Return to ArabPlast Exhibition

Magnetic Separators and Metal Detectors at ArabPlast 2019

After a successful exhibition in 2017, Bunting Magnetics is, once again, exhibiting at the ArabPlast international exhibition (5-8 January 2019, Dubai World Trade Centre, Dubai, UAE).  On stand 5D125, Bunting is exhibiting magnetic separators and metal detectors specifically designed for use in the plastics industry.

Exhibiting in 2017 was a great success,” explained Dave Hills, Bunting’s Head of Sales.  “We had the opportunity to speak with many new potential customers.  We even secured an order for a FF Drawer Filter Magnet and quickTRON Metal Detector on the stand at the show!”

bunting_europe_arabplast_dubai-1335
Simon Ayling and Dave Hills on the stand at ArabPlast 2017

ArabPlast is the largest trade expo for plastics, petrochemicals and rubber industry in the MENA region.  The 2017 exhibition had 906 exhibitors from 41 countries and 27,268 visitors from 119 countries.

On the stand at ArabPlast, Bunting will be displaying a wide range of equipment used to remove metal contamination from the plastics manufacturing process including:

At ArabPlast, the Bunting team intends to help local plastics companies solve any metal contamination problems.  The team is able to draw upon their vast experience in Europe and the USA.

Bunting Europe at Technivation
FF Drawer Filter Magnet

The Bunting team is also looking forward to helping local recycling companies address plastic waste management.  They intend to share experience of working with UK plastic recyclers such as EcoVyn where the installation of FF Drawer Grate Filters reduced waste by 94%.

“Exhibiting at overseas exhibitions is an important part of our marketing strategy,” said Dave.  “It gives us the opportunity to meet local companies and learn about their market.  We can also share our experiences, helping companies solve metal contamination problems, reducing waste and increasing efficiency.  The Middle East and North Africa market is evolving at a rapid pace and offers great opportunities.”

For further information about metal separation equipment designed for removing metal during the plastic or plastic product manufacturing process, please visit us at ArabPlast, go to our website or contact us on:

Phone: +44 (0) 1442 875081
Email: press@buntingeurope.com
Via the website

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24 Drawer Filter Magnets Destined for France

Metal Removed From Plastics

24 Drawer Filter Magnets are under manufacture at our European HQ in Berkhamsted, UK.  The Drawer Filter Magnets are destined for installation in a plastics production operation in France.

Bunting_Drawer_Filter_Magnets-8
Drawer Filter Magnets at an early stage of manufacture

“The Drawer Filter Magnet is one of our most popular magnetic separators,” said Dave Hills, Bunting’s Head of Sales.

The order for the Drawer Filter Magnets was secured by Bunting’s local representative in France, BMS.  BMS specialise in providing technical support to the plastics sector.

Drawer Filter Magnet Specification

All 24 Drawer Filter Magnets have the same specification:

  • Model:  LP-1600-PL: Low Profile Drawer Filter Magnet
  • Magnets:  Three (3) high strength Neodymium Rare Earth Magnets;, three 25mm diameter stainless steel
  • Dimension of the opening:  150mm square
  • Height:  180mm
  • Rows of Magnets:  One
  • Flanges:  Bottom and top included, 6.35mm thick
  • Slide gate:  6.35mm thick
  • Viewing port:  Unit features a 9.5mm thick clear polycarbonate drawer front

Application

During the manufacturing process of any plastic or plastic product, it is possible for metal to be introduced into the process.  This could be from a wide variety of sources including the wear of processing machinery.

Bunting_Drawer_Filter_Magnets-0346

If metal contamination is not removed, it can damage processing equipment and result in increased final product rejects.  The Drawer Filter Magnets are used to attract, hold and thus remove any magnetically susceptible metal contamination.

Another Export Order

“This is another great export order for Bunting,”said Hills.  “Despite all the concerns about BREXIT, we continue to work hard supporting our regionally based distributors.  This is paying dividends as our sales overseas continue to rise.”

For further information about metal separation equipment designed for removing metal during the plastic or plastic product manufacturing process, please visit our website or contact us on:

Phone: +44 (0) 1442 875081
Email: press@buntingeurope.com
Via the website

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3 Successful Plastics Recycling Projects for Recycle Week

Celebrating Recycling Success

The theme of the 2018 Recycle Week (24-30 September)  is ‘Recycling. We do. Because it matters.’  Recycle Week is a celebration of recycling, organised by WRAP under the ‘Recycle Now‘ brand.

Recycling has never been more prominent in the news, with managing plastic waste high on the agenda.  We work with many plastic recycling companies and have provided many magnetic separators and metal detectors to remove metal contamination.  To celebrate Recycle Week we wanted to talk about plastics recycling success and also highlight the changes faced by companies recycling plastic.

EcoVyn Reduce Waste by 94% with Bunting Drawer Magnets

Bunting Magnetics Drawer Magnets at Ecovyn

EcoVyn Ltd is at the forefront of PVC compounding and brings pioneering new technology to the market place.  They offer one of the most advanced and innovative production processes in the UK producing reprocessed, blended and virgin compounds for a variety of applications.  By installing Drawer Magnet Filters, EcoVyn reduced their waste by 94%.

HFS Drawer Magnets Removes Metal from Recycled Plastics

HFS_Grate_Magnet_Plastics-1866

A French plastic recycling company installed the Drawer Magnets to remove fine iron contamination present in the recovered and granulated plastic.  If the metal is left in the reclaimed plastic, it causes serious defects in the new plastic product and can also damage processing equipment.

Metal Separation Module Cleans Recycled Plastics for Recapture Plastics

Bunting Metal Separation System Recapture Plastics LinkedIn

A new plastics recycling plant was built in Kent, UK.  The plant was designed to handle up to 25 tonnes per hour of reclaimed plastic.  Once shredded, the plastic is passed over a strong Drum Magnet (to remove small ferrous metals) followed by an Eddy Current Separator (to remove non-ferrous metals).  The end product is also passed through a Quicktron Metal Detector prior to the clean plastic being bagged ready for shipment.

Contamination Hinders Plastic Recycling

We work with many plastic recycling companies located across the world.  Every company is faced with the problem of contamination.  Contaminated plastic waste is worthless and processing is required to remove contaminants, such as metal and stone, to make this waste product reusable.

We are fortunate to be working with some amazing companies in the waste and recycling sector.  Their innovation and knowledge continually increases the amount of materials we can recycle and reuse.

For further information metal separation equipment designed for removing metal from plastic waste and in other recycling applications, please visit our website or contact us on:

Phone: +44 (0) 1442 875081
Email: press@buntingeurope.com
Via the website

Photographs taken by Paul Fears Photography

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Metal Contaminated Sugar Alert

Latest Metal Contamination Food Safety Alert

On the 28th July 2018, the UK Food Standards Agency released a food alert announcing ‘Tereos UK recalls Granulated Sugar due to the presence of small metal pieces‘.  This is the third report of metal being found in food reaching the consumer in 2018 after six metal contamination alerts in 2017.

Metal In Sugar

Metal enters the food manufacturing process via many different avenues.  Metal can be present in ingredients being delivered to a food processing plant and unless removed at source can enter the process and cause significant damage.  Equipment failure and wear can also lead to metal contamination and is usually removed with the right combination of magnetic separators and metal detectors.

The source of the metal contamination in the granulated sugar is presently unknown and an investigation is most likely underway.  The sugar is sold in the UK by the retailers Iceland, Poundland, and Sainsbury’s and has been recalled.  The metal contamination will be costly in terms of direct financial cost and reputation.

Getting Metal Out of Sugar

Removing metal contamination from granulated sugar is commonly achieved using Drawer Filter Magnets and Plate Magnets.  Plate Magnets are installed in chutes where the sugar flows over the surface.  Due to the small size of the sugar granules Neodymium Rare Earth Plate Magnets are preferable, producing the highest magnetic attractive force to remove small ferrous and magnetically-susceptible work-hardened stainless steel.

SC FF drawer - no tr#14B20B

Due to the potential sticky nature of the sugar, sleeved Drawer Filter Magnets are often preferred, in an easy-clean design.  The Rare Earth Tube Magnet sits tightly inside a fixed stainless steel outer tube.  Cleaning forms part of a daily maintenance schedule, with the Tube Magnets being withdrawn from the sleeves to drag and deposit metal contamination in a discharge chute.

Magnetic Separation Audits

Bunting engineers conduct regular Magnetic Separation Audits at many food manufacturing plants.  An audit involves the visual and physical inspection of every magnetic separator in a plant to check on the location, suitability integrity (ie checking welds and for wear), and magnetic strength (which can deteriorate with excessive heat, weld damage, or if dropped).  In April three Magnetic Audits were conducted and highlighted a number of issues that have since been addressed.

For more information on preventing Metal Contamination Food Safety Scares, or to arrange a free onsite survey and audit of a particular plant or process, please contact the Bunting team on:

Phone:  +44 (0) 1442 875081

Email:  sales@buntingeurope.com

Via the website

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EcoVyn Reduce Waste by 94% with Bunting Drawer Magnets

Magnetic Separators Remove Contamination from Plastic Waste

EcoVyn Ltd has installed two Bunting Drawer Filter Magnets to remove ferrous metal contamination from plastic waste.  Since the installation of the magnetic separators, EcoVyn has reduced their waste by 94%.

Bunting Magnetics Drawer Magnets at Ecovyn
Bunting Drawer Filter in situ at EcoVyn

EcoVyn Ltd is at the forefront of PVC compounding and brings pioneering new technology to the market place.  They offer one of the most advanced and innovative production processes in the UK producing reprocessed, blended and virgin compounds for a variety of applications.

EcoVyn first met Bunting at the Interplas international plastics exhibition in September 2017.  The company use a high proportion of plastic waste, of which 80% is post-consumer.  Presently, EcoVyn processes 1000 tonnes per month of good quality reclaimed plastic waste, which they plan to increase to 16,000 tonnes per annum.  The cleansed plastic waste is blended into virgin material, resulting in a 90% output of grade A product.  Waste generated during the manufacturing process is also recycled leaving less than 1% being discarded.

Bunting Magnetics Drawer Magnets at Ecovyn
Granulated plastic waste

However, plastic waste is often highly contaminated with metal.  Metal Detectors were already installed to remove the metal contamination, but the reject rate was very high with over 60 tonnes of waste being generated, of which a high proportion was good quality plastic.

At Interplas, EcoVyn explained the problem to the Bunting team who agreed to conduct a site review.  During the review it was concluded that easily removable magnetically-susceptible metal could be removed, leaving the metal detectors to detect and separate non-ferrous metals.  This would then significantly reduce the number of metal detector rejections and, therefore, the amount of waste generated.

After a review of the process, Drawer Filter Magnets were recommended to be installed between the screw conveyor transporting the 8-10mm sized infeed material and the metal detector.  The metal-cleansed material would then pass onto a pulveriser before continuing through the process.

The Bunting Drawer Filter Magnet is used widely in the plastics industry and enables the simple and effective removal of ferrous metal from free-flowing materials.  The Drawer Filters installed at EcoVyn have two rows of high strength Rare Earth Neodymium Magnets.  The top row has two Tube Magnets with three in the second row aligned to sit below the gap in the top row.  This ensures that all the product strikes at least one of the Tube Magnets, where ferrous metal is attracted by the strong magnetic field and captured.

Bunting Magnetics Drawer Magnets at Ecovyn
Ferrous metal captured on the surface of the Tube Magnets

After the installation of Drawer Filter Magnets, the amount of waste was reduced from 60 tonnes to 4 tonnes.

Since installing the Drawer Filter Magnets, EcoVyn has established that a 20 minutes cleaning frequency is required, highlighting the high level of metal contamination commonly found in plastic waste.  The ferrous metal found captured on the Tube Magnets ranges from small fine ferrous dust to nails, washers, steel sheet shards and electrical capacitors.

Bunting Magnetics Drawer Magnets at Ecovyn
Ferrous metals captured by the Bunting Drawer Grate Magnet including nails, a capacitor, washer, wire and steel sheet shard

Following the installation of the Bunting Drawer Filter Magnets, controlled laboratory tests have been conducted at Bunting’s Master Magnets facility in Birmingham which indicated that 99.9% of all ferrous metals had been removed.

The final plastic product produced by EcoVyn is then used to manufacture products such as pipe, internal windows, beading, picture frames, and shoe soles.

For further information on separating metal from plastics during the production of the virgin product or during the recycling process, please contact the Bunting team on:

Plastics Positivity at Technivation

Polymer Training and Innovation Centre Hosts UK Plastics Sector Professionals

The Technivation conference, hosted by the Polymer Training and Innovation Centre in Telford (18th April 2018), attracted delegates from across the UK plastics sector.

The Polymer Training and Innovation Centre (PITC) provides training for engineers working with plastics and has an extensive range of working equipment including moulding machines, pneumatic conveying systems, and magnetic separators.

Bunting Europe at TechnivationAt Technivation, there were talks from machinery manufacturers and also an industry update from the British Plastics Federation.  BPF Membership Services Director, Stephen Hunt, highlighted a change in the awareness and public perception of plastics since the airing of the BBC Blue Planet II series at the end of 2017.  The BPF have been working hard to clarify misconceptions about plastics, highlighting that plastic is vital in the manufacture of so many products including cars, medical equipment, and IT.  They are presently working closely with the UK Government on the proposed tax for single use plastics, which closes on 18th May 2018.

As Stephen Hunt explained, the plastics sector is the 8th largest exporting industry in the UK with a turnover of £25.5 billion.  The sector is also the 2nd largest employer in the manufacturing industry.  He also highlighted how waste from the USA and European Union combined only contributes 2% to the amount of plastic waste found in our oceans.

Delegates at Technivation had the opportunity to tour the training facility and meet representatives from equipment manufacturers including Summit Systems, Kistler, Arburg, and Staubli.  Tom Higginbottom, Bunting’s Sales Engineer, was demonstrating how to effectively remove metal from the plastics process using a combination of a FF Drawer Filter Magnet and Quicktron Metal Detector.

“At Technivation it was really good to be able to demonstrate how to remove metal and also to show how the equipment is actually installed on a working moulding machine,” explained Tom.  “We supplied the FF Drawer Filter Magnets to PTIC so that the importance of metal removal is included in the training programmes.”

For further information on separating metal from plastics during the production of the virgin product or during the recycling process, please contact the Bunting team on:

Bunting Europe at Technivation

Polymer Training and Innovation Centre Protected by Bunting Drawer Filter Magnet

Magnetic Separator Technology for Plastics Training

The Polymer Training & Innovation Centre in Telford has added a Bunting Magnetics Drawer Filter Magnet to the range of equipment at their plastics manufacturing training facility.  The FF Drawer Filter Magnet attracts and captures any fine and coarse magnetically susceptible materials that enter the plastics manufacturing process.

Bunting FF Grate Magnet
A Bunting Magnetics Europe FF Grate Magnet included in a plastics production line at the Polymer Training and Innovation Centre in Telford

The Polymer Training & Innovation Centre provides polymer training and consultancy, specialising in injection moulding, blow moulding and extrusion training.  They are a technical training and consultancy business that is owned by City of Wolverhampton College.

At their Telford training facility, the Polymer Training & Innovation Centre has working production-sized plastics manufacturing equipment for injection moulding, blow moulding, thermoforming, materials handling, and a wide range of other important ancillary equipment.

Technical Trainer, Andrew Dermody, explained the importance of trainees having practical training on the equipment.

“We have great support from the industry and equipment manufacturers such as Bunting.  This support means that we can deliver practical training, with a hands-on approach, and that is the best way for our delegates to learn.  Having the Drawer Filter Magnet installed exactly as it would be in a production plant, is an ideal way to show our students best-practice and highlight the importance of metal removal.”

Bunting FF Grate Magnet

The training facility at Telford was refurbished in early 2017 and Bunting supplied the FF Drawer Filter Magnet in March 2018.  The FF Grate Magnet is bolted onto the bottom flange of a Summit Systems fed hopper.  The Magnetic Separator has a transparent front plate so that operators are able to see the material passing through or held within the system.  Virgin plastic beads fall from the hopper through two rows of high strength Tube Magnets, which attract and hold any magnetically susceptible materials.  The Tube Magnets use ultra-strong, permanent, Neodymium Rare Earth Magnets.  The cleaned plastic beads are then fed into the Engel injection moulding machine.  Removing all metal contamination ensures that the final plastic product is free from defects and reduces the amount of waste and potential damage to moulding machines.

Bunting FF Grate Magnet

On a regular frequency, dictated by the amount of metal captured, the Tube Magnets are removed as one complete assembly from the housing and cleaned.  The design of the Drawer Filter Magnet means that removal of the Magnet Assembly is quick and easy, keeping maintenance times to a minimum.

“The Bunting design is good as it is very visible,” said Dermody.  “Often Magnetic Separators are placed out of sight in hoppers, which means that they can be forgotten.  In this installation, the Drawer Filter Magnet is right in front of the machine operator and the clear front allows easy visual checking of the magnets.”

Bunting also supplied Drawer Filter Magnets for use in the classroom and the Polymer Training & Innovation Centre plan to incorporate ‘metal separation’ as one of the course topics.

The Drawer Grate Magnet is widely regarded as standard for the plastics industry and Bunting has supplied thousands to plastics manufacturing operations globally.

“It is great that delegates are able to see, in practice, the importance of having good Magnetic Separation equipment in the plastics process,” said Tom Higginbottom, Bunting’s Sales Engineer.  “Even with virgin raw materials, there is always a small amount of fine ferrous metal contamination and there is always the risk of larger tramp iron that could seriously damage the injection moulding machine.”

On the 18th April 2018, the Polymer Training & Innovation Centre is staging the Technivation event at their recently upgraded training facility in Telford.  During the day there will be a series of short technical presentations, the opportunity to experience their Polymer on-line simulation software, and the chance to meet and talk with primary and secondary equipment suppliers including Bunting Magnetics.  Visitors will be able to learn more about Polymer Apprenticeship’s and Funding and discuss their organisations own training requirements.

For further information on separating metal from plastics during the production of the virgin product or during the recycling process, please contact the Bunting team on:

Bunting FF Grate Magnet
A Bunting Magnetics Europe FF Grate Magnet included in a plastics production line at the Polymer Training and Innovation Centre in Telford

Review of the Bulk Solids and Powders Industry in Poland

Tom Higginbottom Reports Following Attending the SyMas Exhibition

Last week, our Sales Engineer Tom Higginbottom spent 2-days at the SyMas Bulk Solids and Powders exhibition in Krakow, Poland with Bunting’s local representative, TEKPRO.  Whilst at the show, he gained an insight into the present state of the market and potential opportunities for UK exporters.Bunting_at_SyMas17-17

Tom gives us his insight in the show, local feelings about BREXIT, and the market in general

“SyMas was a really good show with a busy footfall.  There was a lot of equipment on show, from manufacturers based all over the world.

From the type of enquiries and from talking to clients and our distributor, it is clear that the bulk solids and powders sector is growing.  Despite being a member of the EU, Poland remains an emerging nation and wages are still lower than in more developed European countries like the UK, Germany and France, but that gap is closing.  Their skill base is very high and consistently improving.

There is a lot of Western European investment and many of the manufacturing facilities are state-of-the-art.  This matched with the lower wage cost and workforce skills make the Poles very competitive in both European and global markets.

It was interesting speaking with the Poles about the UK leaving the European Union.  Generally, people thought that being a part of the EU makes it possible to compete with larger economies such as China and the USA.  Brexit has introduced an unknown factor and there was a feeling that, without the UK, the EU would have less negotiating power on the world stage.SyMas Tube Magnets 2

I think that the growth of our local representative TEKPRO highlights the expanding market and potential opportunities in Poland.  Since they were founded 10 years ago, they have expanded their workforce from 4 to 84 people.  It is an exciting time and we are working closely with them to maximise our sales potential in Poland.

At the show we received enquiries for both Magnetic Separator and Metal Detectors, including 3 specific projects where clients require Pneumatic Self Clean Drawer Filter Magnets and Drum Magnets.

Attending the SyMas show was really worthwhile and allowed me to gain an insight into the market which simply is not possible without being at the exhibition.

krakow

And Krakow was a beautiful city.  I have never been before and found the people wonderfully friendly and the historical buildings beautiful.”

For further information on removing metal contamination from bulk goods, powders and granules with Magnetic Separators and Metal Detectors please contact us on:

Other relevant Bulk Goods, Powders and Granules Articles

 

Developing Business in Poland at SyMas 2017

Bunting Support TEKPRO at International Trade Fair for Powder & Bulk Solids Technologies in Krakow, Poland

As part of their export business development strategy, Tom Higginbottom from Bunting will be supporting their Polish distributor TEKPRO at SyMas, the powder and bulk solids trade fair in Krakow, Poland (18-19 October 2017).

SyMas is an international exhibition focused on the processing, transport and storage of bulk goods, powders and granules.  TEKPRO are on stand A68.Bunting_at_SyMas17-2

Company TEKPRO Sp. z.o.o. was founded in March 2007 by Danish company TEKEMAS A/S  and the Swiss Dietrich Engineering Consultants sa .  They specialise in providing individual equipment and complete plants to handle and process bulk materials to the Polish market.

“Attending the exhibition and supporting the TEKPRO team is very important,” explained Bunting’s Sales Engineer Tom Higginbottom.  “Being at SyMas allows us to gain an understanding of the market, meeting existing and potential customers, and discussing the industry in general.”

Bunting_at_SyMas17-1TEKPRO will be displaying Bunting FF Drawer Filters and Grate Magnets on the stand.  Tom and the TEKPRO sales team will be giving advice to visitors about eradicating the problem of metal contamination using both Magnetic Separators and Metal Detectors.

“Over the next 2-days it will be great to have an opportunity to get to know the TEKPRO team.  We will also take the opportunity to provide some additional training.  We are really looking forward to the show, and spending time in a very beautiful city,” said Tom.

For further information on removing metal contamination from bulk goods, powders and granules with Magnetic Separators and Metal Detectors please visit the TEKPRO stand at SyMas or contact us on:

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The Challenges of Removing Fine Iron from Powders

Magnetic Separators Designed for Processing Powders

Removing metal contamination when the tramp metal and material is granular is far more straightforward than when in a powder form.  To determine the best solution to remove fine iron contamination from powders, it is necessary to have a good understanding of the way the fine materials behave.

Powders are produced and used in a wide variety of industries including food, pharmaceuticals, refractories, and chemicals.  It is estimated that 80% of materials used in industry are in a powdered form.

flour-791840_960_720A ‘powder’ is defined as fine dry particles produced by the grinding, crushing, or disintegration of a solid substance.  The nature of a powder means that the handling and processing tends to be problematic as powders exhibit similar properties to both solids and liquids.

Metal contamination, commonly in an iron form, can be introduced into a material at any stage within a process.  Tramp metal that is undetected and remains in the product before the powder production stage, becomes significantly reduced in size and, subsequently, increasingly difficult to extract.

Magnetically susceptible metal contamination (i.e. iron) is commonly removed using Magnetic Separation Equipment, which traps metal using Ceramic Ferrite or Rare Earth Neodymium Iron Boron (Neodymium) Magnets.  Although there are Magnetic Separators where the magnetic field is produced via an electrical current, the vast majority utilize permanent magnets such as Ceramic Ferrite and Rare Earth Neodymium Iron Boron (Neodymium).  Ceramic Ferrite Magnets produce low strength but deep magnetic fields, while Neodymium Magnets create the strongest permanent magnetic presently commercially available.

Where Does The Metal Originate?

Metal contamination commonly originates in a powder from two sources:

  1. Primary large tramp metal, such as a nail, screw or bolt;Tube Cartridge Magnets Bunting Magnetics-5
  2. Primary or Secondary fine tramp iron. Primary fine iron or magnetic particles are often present in the raw material.  This originates from primary processing, transportation, or even naturally occurs in the original material.  Secondary fine iron originates from a larger tramp metal source that has been reduced in size during the process.  Typically, this could be from a nail, screw or bolt that has been through a size reduction process, or from damaged or worn processing equipment.  Another common source of secondary fine iron contamination is rust, falling into the process from weathered and worn processing equipment such as chains, hoists, and building cladding.

The separation and detection of tramp metal is easier when the metal contamination is in a larger form and can be successfully removed using a wide range of suitable Magnetic Separators and Metal Detectors.  Magnetic Separators using standard strength Ceramic magnets, with deep magnetic fields, are ideal.  A good example is the Plate Magnet, often installed in a chute, in a housing, or as part of an In-Line Magnetic Separator.

Quicktron05A_Sodium Bicarbonate 2

Larger metal contamination is also easier to detect on a Metal Detector.  Metal is detected as it passes through the coil of the Metal Detector and an automatic reject system removes it from the flow.  For detection, the magnetic field generated by the Metal Detector has to see a state change.  Finer sized metal produces a lesser state change and thus increases the difficulty in detection.

In a project in Pakistan, a processor of fine Sodium Bicarbonate is using a Quicktron Metal Detector to remove the larger tramp metal.

Removing larger tramp metal with a Magnetic Separator and Metal Detector prior to the processing stage not only prevents the metal from being reduced in size (e.g. converted into a secondary source of fine iron contamination), but also protects delicate processing equipment such as granulators, shredders, and mills from being damaged by the metal.

Once in a powder form, there are processing parameters to consider when assessing the optimum method to remove fine iron contamination.

How Does a Powder Flow?

When a powder is sprinkled, it remains light and free.  However, when the same powder is vibrated or compressed, it may become very dense and even lose the ability to flow.

Individual grains in a powder cling to each other in clumps, in accordance with the Van der Waals force.  This coagulation often results in the fine iron being trapped in among clean product.  The ability of any Magnetic Separator to attract, hold and separate the fine iron is dependent on the iron being as close to the magnetic field as is physically possible.  If the fine iron contacts the surface of a Magnetic Separator with a high strength magnetic field, it will be held.  However, when the fine iron is held inside a coagulation of powder, then it could be held out of the reach of the maximum magnetic force.  Thus, it will not be separated.

The way a powder flows impacts on the design of the Magnetic Separator.  Powders flowing in a hopper may experience classic flow problems such as ratholing, bridging or flooding, all of which could be exacerbated by the design of Magnetic Separator.

Different Designs of Magnetic Separator

Plate Magnets Bunting Magnetics-9797High strength magnetic fields, as produced by Neodymium, are needed to capture fine iron metal contamination.  There are four main magnet configurations suitable for handling powders.

  1. Tube Magnets (also known as Rod Magnets and Cartridge Magnets), often in a multi-rod Grate configuration;
  2. Flat-faced Magnetic Plates;
  3. Cone-shaped Magnets;
  4. Magnetic Drums with a curved magnetic arc;

Although occasionally a Tube Magnet may be used on its own, it is more commonly part of a larger multi-cartridge Grate system.  The Magnetic Grate is designed to fit inside a hopper, or can be supplied complete with a housing (i.e. as a Drawer Filter Magnet).ff-neo-4

In operation, powder falls freely onto the surface of the Tube Magnet where fine iron strikes the surface and is held by the strong magnetic field.  To ensure that the powder makes contact with the Cartridge surface, deflectors are often deployed above the gaps between the Cartridges.

Powder build-up on the surface of a Magnetic Cartridge will reduce the separation efficiency.  Also, in severe cases, a slight build up on the surface of the Cartridge may quickly cause a blockage of the whole housing.

Such blockages can be prevented by ensuring that there is optimum space between the Magnetic Cartridges.  Also, in some cases, the mounting of an external vibrating motor on the side of the hopper or housing will provide enough disturbance to prevent any material coagulation.  The frequency of the vibration needs careful consideration as it could affect the flow ability of the powder.  Additionally, when vibrators are used, the Magnetic Cartridges need to be manufactured to withstand prolonged periods of vibration.

Bunting Teardrop Tube Magnet

‘Teardrop’ shaped Tube Magnets are specifically designed to stop the build-up of fine powder on the surface.  The sharp edge of the teardrop faces up into the product flow and allows material to flow around the edge and into the magnetic field.  Magnetic particles are captured and held underneath the Tube Magnet.

Flat-faced Magnetic Plates are ideal when it is possible for the material to flow over the surface.  For fine iron removal, the Magnetic Plates would use high strength Neodymium Magnets.  This magnetic field is further enhanced when a Tapered Step is added to the face of the magnet.  Captured iron migrates behind the step and away from the material flow, reducing the risk of re-entering the cleansed product.

As well as being fitted into chutes, Magnetic Plates are incorporated into housings.  The Plate Housing Magnets resist bridging and choking to remove tramp iron and ferrous fines from flow-resistant bulk materials.  The stainless steel housings mount easily to enclosed spouting or directly on processing equipment.

There are optional square, rectangular, and round adapters for easy connection to existing chute work.  A baffle at the top of the housing helps break up clumps and directs product flow over the unit’s two powerful Plate Magnets.

Bunting Magnetics In Line Magnet

Plate Magnets are also used in In-Line Magnets and there are two designs:

  1. Gravity In-Line Magnets (GIM) – The Plate Magnets are positioned in round, sloping spouting where material is under gravity flow.  For effective tramp metal capture, the spouting should be angled no more than 60° from horizontal;
  2. Pneumatic In-Line Magnets (PIM) – These designs are for use in dilute phase pneumatic conveying systems (up to 15psi). They can be installed easily with optional factory-supplied compression couplings and work best in horizontal runs with the plate magnet down to take advantage of material stratification;

Another design of In-Line Magnet is the Center-Flow, although the magnetic field is generated in a Cone configuration instead of a Plate.  The Magnetic Cone is positioned in the center of the housing, allowing the powder to flow in the space left between the housing.  Center-Flow In-Line Magnetic Separators are commonly used in dilute-phase pneumatic conveying lines up to 15psi.

To achieve optimum contact with the product flow, a conical magnet is suspended in the center-line of the housing.  This tapered, exposed-pole cartridge has a stainless steel “nose cone” to direct the flow of materials around the magnet.  The tapered poles of the cone magnet allow ferrous fines to collect out of the direct air stream.  Additionally, the trailing end of the magnet is an active magnetic pole and holds any tramp metal that is swept down the cone.

Both types of In-Line Magnet are designed with clamps and doors to enable easy access for cleaning.

drumIn specific applications, a high strength Neodymium Drum Magnet will enable the best level of separation.  The Drum Magnet is gravity-fed, usually via a Vibratory Feeder.  The Drum Magnet has a stationary high-strength magnetic arc positioned inside a rotating outer shell.  When material flows onto the drum magnet, the magnetic field projected by the stationary magnetic assembly inside the shell captures fine iron and holds it securely to the drum’s stainless steel surface.  With contaminants removed, the good product falls freely to a discharge point.  As the drum rotates, the captured fine iron travels along the drum surface and out of the magnetic field, where it is discharged.

There are various magnetic field configurations possible, but the most suitable for removing iron from powder is one that produces a Radial Magnetic Field.  This ensures that once captured, the fine iron does not leave the Drum surface until it moves out of the magnetic field.

Processing powder on a Drum Magnet presents more difficulties that other designs of Magnetic Separators.  Firstly, it is recommended that the Vibratory Feeder has an air bed to produce a consistent feed of powder.  Standard Vibratory Feeders may deliver powder in clumps, significantly affecting the separation performance.

Secondly, the shell of the Drum Magnet should be rotated at high speeds.  This will result in some of the powder pluming, and this can be minimized by keeping the distance between the end of the Vibratory Feeder Tray and the rotating surface of the Drum Magnet to a minimum.

The high rotation speed of the Drum Magnet significantly reduces the amount of product lost to the magnetics.  This is because there is less material on the surface of the Drum at any one time, reducing the chance of entrapment.

The use of Drum Magnets operating at high rotational speeds has been very successful in removing fine iron from abrasives, refractories, and other applications where the material has a high specific gravity.

Ensuring Powder is Metal-Free

As the demand for finer and purer powders increases, so does the need to remove even the finest iron.  Understanding the properties and behavior of the powder is vitally important when considering the optimum method of fine iron separation.  Often the ultimate solution is a series of Magnetic Separators and Metal Detectors located at strategic points within the process.

For further information on removing fine metal contamination from powders with Magnetic Separators and Metal Detectors please contact us on: