Ask an Expert

Q: Is the clean bag startup procedure (seeding) the same for a filter-receiver as it is for a dust collector?

John Constance, The Engineers Collaborative, says: Fine dust particles can leak through the surface of new filter bags and filter cartridges. Precoating (also called seeding) the filters improves startup efficiency by minimizing fine particle bleed through. Also, precoating the filters improves filter life by stopping fine dust particles from embedding themselves within the filter material.

The standard procedure for precoating new filter media, whether for a dust collector or filter-receiver, is as follows:

1. Turn off the filter-cleaning system during the precoat process and be sure to shut down the fan or blower.


2. Remove the old filter media and install the new filter media. Be sure to remove all of the old filter media. Don’t mix old media with new.

CONTINUED...

John Constance is a consulting engineer for The Engineers Collaborative and a member of PBE’s Editorial Advisory Board.

Editor's note: Send your comments or questions about this or other issues related to handling and processing dry bulk solids to awiebe@cscpub.com.

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In the June 1 issue of PBE-News, an Ask the Expert article by Clint Scoble of Filter Media Services LLC discussed selecting filter media for combustible materials.

Click here to read one reader’s comments on the article and Clint’s response.

Q: We have a highly hydroscopic material that we have to meter out of bulk bags. It’s also corrosive to metals. How can we meter and discharge it properly to a belt feeder?

read the answer

Feature

A.B. Flower, A&J Mixing International

Are you in the market for a new mixer, yet feel confused by the whole process of mixing? You’re not alone. Many mixer manufacturers talk at length about their products but don’t define what makes a good mixture, what size samples to take for measuring mixture quality, or what method to use when analyzing the samples’ mixture quality. However, it’s important to clearly define all three to be sure that your mixture meets your requirements and delivers the performance you need.

Read It Here First:

Carl Swisher, Tapco Inc.

The centrifugal discharge bucket elevator is one of the most commonly used mechanical conveyors for transferring large volumes of dry bulk materials vertically. Typically, plastic buckets are used in this elevator because of their durability, long operating life, abrasion resistance, noncorrosive and nonsparking properties, and other qualities. Plastic buckets that show abnormal wear or damage may indicate that your elevator is running outside standard operating parameters and will require adjustment or different buckets to keep running efficiently.

Properly maintaining your centrifugal discharge bucket elevator maximizes elevator throughput and efficiency, cuts maintenance costs, and keeps your operation running smoothly. To ensure proper bucket elevator operation, you need to be able to identify and distinguish the different types of bucket wear or damage. Below are three common examples of bucket wear or damage, the elevator problems they symptomize, and ways to solve the problems.

1. Buckets are covered with material after discharge, diminishing the elevator’s throughput or creating cross-contamination issues.
The buckets are made of an inappropriate material for your application, and you’ll need to replace them with urethane buckets, which resist adhesion and also "flex" to knock out the material.


2. Buckets’ front lips are worn and have sharp edges.
This implies that the elevator’s belt or chain is improperly tensioned. You’ll need to increase the belt or chain tension to prevent the buckets from sliding along the bottom of the boot.


3. Buckets’ interior surface is worn, exhibiting a sandblast effect.
This means that the material’s feed velocity into the bucket is too high. To prevent this, you’ll need to reduce the material’s infeed velocity, install baffles at the leg entrance, or replace the existing buckets with more abrasion-resistant urethane buckets.

For more bucket problems and how to deal with them, you can read "Bucket elevator: Diagnosing and solving seven common problems" by Carl Swisher, Tapco Inc., in the July issue of Powder and Bulk Engineering.

To read it today, click here.

International and National Industry News

MPIF presents distinguished service awards

The Metal Powder Industries Federation (MPIF) presented several powder metallurgy industry professionals with its Distinguished Service to Powder Metallurgy Award during the 2011 International Conference on Powder Metallurgy & Particulate Materials in San Francisco. For more information and a list of recipients, visit www.mpif.org.

ISA publishes second edition of instrumentation book

The North Carolina-based International Society of Automation (ISA) has announced the publication of the second edition of its book Instrumentation and Control Systems Documentation by Fred A. Meier and Clifford A. Meier. This second edition incorporates improvements suggested by readers and those that reflect subsequent changes in industry practice. www.isa.org.

Vidrios Lirquén to open plant in Peru

Vidrios Lirquén, a joint venture between NSG Group, Saint-Gobain Glass, and Inversiones Pathfinder, has announced plans to build a new float line in Lima, Peru. The plant, which will open in 2014, will have a daily glass output of 800 tons and will supply Peru’s construction and automotive markets. For more info, visit www.nsg.com.

Supplier News

BEUMER to open office in Scandinavia

International logistics provider BEUMER, Germany, has announced it will open a new office in Scandinavia to better service its customers in that region. The company supplies specialized conveying, palletization, packaging, and distribution solutions to a variety of industries. Click here for more info.

Editor's note: Send your news items to awiebe@cscpub.com.

Events

Seminar to discuss solids flow

Jenike & Johanson will host its 8th annual "One day at J&J" solids handling seminar on July 14 at its office in Tyngsboro, Massachusetts. The course will provide insights into common flow problems that arise when bulk solids are put into silos, bins, and hoppers. Visit the seminar info page for more information and to register.

Continuing Education

Webinar to discuss central vacuum cleaning design

PBE will host the webinar “Designing Effective Central Vacuum Cleaning Systems” at 12:00 p.m. CST on Thursday, July 7. Gary Johnson will discuss central vacuum cleaning system design strategies that work for system sizing and layout for maximum operability while conserving electrical power consumption. Click here for more information and to register.