Dateline: April 17, 2007

News
Technically Speaking

North America

U.S. Presence Increased
Brenntag has acquired U.S.-based Ulrich Chemical, a distributor of chemicals and services to pharmaceuticals, food and beverages, paint and coatings, plastics, water and wastewater treatment, cosmetics and personal care.  In 2006, Ulrich had sales of $83.6 million.

World

Restart
Huntsman’s polyurethanes division’s joint-venture crude MDI facility in Caojing, China that’s been offline since mid-December is currently undergoing repairs to replace a damaged heat exchanger.  The facility should resume production this quarter.  The joint venture includes Huntsman, BASF, Shanghai Hua Yi, Shanghai Chlor-Alkali Chemical and Sinopec Shanghai Gao Qiao Petrochemical.  Huntsman’s downstream majority-owned MDI finishing and pre-polymers operation is still running and uses MDI imported from other Huntsman facilities.

Bioethanol Plant
A 100,000 ton/year bioethanol plant will be built in Brzeg Dolny, Poland.  Unicorn Chemical of Northville, Michigan plans to spend $26.7 million to build the plant and will export all of the plant’s output.  Delta-T of Williamsburg, Virginia will be the source for the plant’s technology.

Technically Speaking

What is a "saltation velocity" and how is it used in designing pneumatic conveying systems?

The saltation velocity is defined as the actual gas velocity (in a horizontal pipe run) at which the particles of a homogeneous solid flow will start to fall out of the gas stream.

In designing, the saltation velocity is used as a basis for choosing the design gas velocity in a pneumatic conveying system. Usually, the saltation gas velocity is multiplied by a factor, which is dependent on the nature of the solids, to arrive at a design gas velocity.

For example, the saltation velocity factor for fine particles may be on the order of 2.5 while the factor could be as high as 5 for course particles such as soy beans.