| Upcoming Training Courses:
Rio Grande, Puerto Rico November 10-12, 2008
Atlanta, Georgia December 10-12, 2008
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| Greetings!
Welcome to our cement e-newsletter, which focuses on industry events and solutions to costly bulk material handling problems. 
Even though the demand for cement in the US has been reduced by about 9% in 2007 compared to 2006 (per Portland Cement Association Monitor V. 18, No. 1, January 2008) due to softening domestic economic conditions, many opportunities exist to upgrade, repair, and replace inefficient, poorly operating bulk solids equipment. Whether you have silos that have material hang-ups, transfer chutes that plug and cause excessive dusting, or pneumatic lines that wear prematurely in elbows, proven, practical solutions are available to solve these expensive problems.
Jenike & Johanson is prepared to assist you with projects at your cement plants whether domestic or throughout the world. This e-newsletter is a launching point for helping you to understand how to solve on-going flow difficulties and how to prevent problems with new production lines.
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2009 IEEE/PCA Tutorial Offering
We are pleased to announce our one-day tutorial at next year's 51st IEEE/PCA conference to be held May  31-June 4, 2009 in Palm Springs, California, USA. This practical and interesting course will arm engineers, plant managers, production superintendents, and operators with the knowledge required to reliably handle challenging bulk materials such as limestone, clay, gypsum, and fly ash. Topics covered in this valuable tutorial will include:
- Solving bridging and ratholing problems
- Understanding hopper flow patterns (funnel and mass flow)
- Characterizing raw and finished material flow properties
- Selecting and designing bulk solids feeders
 (belts, screws, rotary valves)
- Key principles for transfer chute design
- Troubleshooting problems with pneumatic systems
- Proven, effective design approach for pneumatic transport
This course is highly recommended for personnel at a cement plant involved in selection and operation of bulk material handling equipment. Though registration at www.ieee.org is not yet available, save the date on next year's calendar so that this important opportunity is not missed!
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Why Kiln Feed Interruptions Occur
It is imperative to keep raw meal (kiln feed) flowing into a kiln in a dry process plant (95% of US plants are dry process). Flow interruptions can be caused by material hang-ups in raw mix storage silos, transfer chutes, or mill feed bins. Two common blockages,  called bridging and ratholing, can readily cease flow from a hopper when handling cohesive bulk materials, like clay, gypsum, or fine/moist limestone. These interruptions not only affect production capacity, but they also affect chemistry of the clinker being produced in the kiln. Clinker requires an accurate proportioning of critical chemicals containing calcium, silica, alumina, and iron, and if these raw materials hang up in storage vessels, then high chemical variations can result.
For instance, have you ever wondered why the LSF or silica/alumina moduli vary during raw meal handling? This could be due to flow interruptions during raw mix formulations or due to segregation of raw meal during filling and feeding out of "homogenization" silos.
 Not only can flow interruptions cause headaches at a cement plant, but other difficulties such as excessive dusting, wear of equipment, and buildup in chutes or conveyors, will often require manual labor to address costly problems, thereby diverting valuable resources from other duties.
If your cement plant is currently experiencing flow problems, Jenike & Johanson can help you. Or, if you are planning for a new plant or production line, we can apply our industry-leading technology and years of experience to help avoid process upsets due to handling cohesive, sticky, and abrasive bulk materials.
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| Did You Know...
- Concrete, with solids composed of cement, sand, and aggregate, is the second most widely
 consumed substance on Earth, after water!
- According to the US Census 2000 and USGS Mineral Survey, the average person in the US uses about 900 lb. (about 400 kg) of cement each year!
- According to the US Department of Transportation, 60% of the interstate highway system is composed of concrete with advantages of superior durability, reflectivity, and traction over traditional asphalt
- Concrete structures built in Egypt 3,600 years ago are still standing!
- Cement can behave like a solid (such as a caked material in a silo) and a liquid (such as when filling bags); both behaviors can present difficulties.
Learn about other cement applications in our case study section!
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Cement-Related Papers
 "Successful Stockpile Operation", Bulk Materials Handling Review, A Supplement to World Cement, August 2008, by Eric Maynard
- "In Safe Hands; Limestone and Clay Handling Strategies", World Cement, May 2005, by Eric Maynard
- "How to Design Transfer Chutes to Eliminate Spillage and Dusting", presented at the North & South American Cement Conference, Miami, Florida, May 13-16, 2002, by Eric Maynard
- "Pneumatic conveying problems? Practical Solutions for the Cement Industry", presented at the 3rd North & South American Cement Conference, Miami, Florida, February 8-10, 2004, by Eric Maynard
Email or call Jenike & Johanson at 978-649-3300 for details about these publications.
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Background of Jenike & Johanson
Jenike & Johanson is a consulting engineering firm specializing in the science and technology of bulk solids handling. In our four laboratories in the United States, Canada, and Chile, we have tested more than 10,000 bulk solids and used the results to design accurate, cost-effective solutions to flow-related problems for more than 3,000 companies around the world in such industries as cement, chemicals, pharmaceuticals, energy, mining, consumer goods, solid waste, and more.
We have over forty years experience applying practical, science-based technologies to implement robust processes, and a history of solving difficult challenges others cannot resolve. | |
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We look forward to providing you with practical, cost-effective solutions to your bulk solids handling problems.
Sincerely, |
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Eric Maynard
Jenike & Johanson, Inc.
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