High Density Cleaners

SKU: C-694Duration: 21 Minutes Certificate Included

Pay-per-view (PPV) format perfect for individual users.

Get immediate access to this interactive eLearning course online. Must be used within 30 days, expires 48 hours after launch.

Great for in-person classroom training or as an alternative to DVD.

Includes printable documents and Convergence Video Player for Windows systems. Content expires after 1 year.

Ideal for corporate licensing and volume users who also need administrative tracking and reporting on training.

Get this interactive eLearning course into your LMS or learn how you can leverage our LMS to deliver training to your workforce.

Need multiple courses or have lots of users? Just let us know a little more about what you need and we’ll get you some great volume pricing.

 Need help deciding? Compare delivery formats.

Course Details


Training Time: 21 minutes

Compatibility: Desktop, Tablet, Phone

Based on: Industry Standards and Best Practices

Languages: English

High density (or HD) cleaners are large diameter forward cleaners capable of processing several hundred tons of fiber per day. The main purpose of high density cleaners is to separate heavy contaminants from fibers in suspensions of fibers in water (often referred to as "stock"). This protects downstream equipment from excessive wear and damage. They may also be used for fiber recovery. This module will describe the operation of high density cleaners and identify typical applications of high density cleaners in secondary fiber, pulp mill, stock preparation, and broke systems.

At the end of this module, you will be able to:

  • Describe how high density cleaners differ from other centrifugal cleaners
  • Identify safety hazards associated with high density cleaners
  • Identify the purpose of high density cleaners
  • Describe the operation of a "junk trap" during a dump cycle
  • Describe the purpose of the main components of a junk trap
  • Identify typical applications of high density cleaners in secondary fiber, pulp mill, stock preparation, and broke systems

The following key questions are answered in this module:

What is the purpose of high density cleaners?
Their main purpose is to separate heavy contaminants from fibers in fiber-water suspensions in order to protect downstream equipment from wear and damage.

Where are high density cleaners typically used?
They are often used in secondary fiber systems, pulp mills, paper and board machine thick stock systems, and broke systems.

How are high density cleaners different from other forward cleaners used in the production of paper and board?
High density cleaners are larger in size physically, discharge their rejects intermittently rather than continuously, and operate with higher feed stock consistencies than other forward cleaners.

What is the purpose of the elutriation water in a high density cleaner?
A continuous stream of elutriation water is used to flush fibers out of the rejects chamber, at the bottom of the cleaner, during cleaner operation.

How often are the junk traps on high density cleaners emptied?
The frequency of the junk trap dump cycle and the length of the purge depends on the level of contaminants in the stock suspension.

Below is a transcript of the video sample provided for this module:

High-density cleaners are specifically designed to remove high and medium-density contaminants or contaminants with high and medium specific gravities from stock. Contaminants such as rocks, nuts, bolts, nails, paperclips, staples, glass, and other heavy debris are removed by the cleaner. High-density cleaners are not designed to remove wax or other low-density or low specific gravity materials. The stock suspension is pumped tangentially into the top of the cylindrical cleaner body at relatively high velocity. As the stock flows inward, centrifugal force and fluid sheer create a vortex near the center of the cleaner. Dense materials move to the outside wall and drop down into a bottom rejects collection chamber. The fibers migrate to the center vortex and travel upwards to the accepted stock outlet.

Use the additional resources and links below to learn more about this topic:

Customer Q&A

Ask a Question

Sorry, we're missing some information

How do I log in to watch a video that I have already paid for?

Easy! Moments after you purchase your pay-per-view (PPV) course, you'll receive an email with login details. Just click the link and log in with your user name and password and you're on your way!

I would like to have some of my employees take 5 of your driving related courses, how can i set this up?

We're in the process of making bulk purchases and purchases for multiple users easier. But for now, you can order multiple courses and just let us know who you'd like to assign courses to. With an email for each user, we can set up their training plans and make sure everyone gets the eLearning assignments they need.

How can I get your paper-making courses for free?

Well, we can't blame you for asking... And while we're a for-profit company, there are situations with students and certain educational organizations where we can help out with a selection of eLearning. However, our online courses are extremely economical. And our paper industry courses are in very high demand. So, without knowing more about your situation, we think you'll get loads of value from the $39 you'll spend on any of our premium courses.

Do you have eLearning in Portuguese?

Yes, we do! And in addition to primary English narration, we produce many courses in a growing number of languages, including Spanish, Chinese, Dutch, German, Italian, Japanese, Korean, Polish, Russian, Tamil, and Thai.

I'm unemployed, but I really like your eLearning. Do I get a certificate when I complete a course?

Yes! All of our courses allow you to print a completion certficate upon successfully passing the integrated test at the end of eLearning. In the future, we'll have badges for you to use in your LinkedIn profiles.
Added to Cart! Click here to view your cart.