Chemical Processing - March 2008 - (Page 42)

>> PROCESS PUZZLER Long Lasting Won’t Rust or Corrode Avoid Down Tme Save on Maintenance 15-Year Shell Warranty Compare the economics of the solutions. Also, check the physical properties of the caustic solution to make sure there is no salting out. Girish Malhotra, president EPCOT International, Pepper Pike, Ohio Not Harmed by H2O Chemical Treatments Delta Cooling Towers designed the first engineered plastic (polyethylene) cooling tower in 1971. Since then we’ve improved and expanded “The Most Durable Corrosion-Proof Cooling Towers Available” to a full line, factory assembled and ready for any application. Visit us at www.deltacooling.com, or call 1.800.289.3358. The Greatest Thing Since a Delta Cooling Tower. Consider several options A 1-in. line is very small. It is hard to prevent steam from cooking off the water, which forms steam and escapes preferentially leaving the caustic behind. There may be several solutions to this problem. Here are a few that come to mind: 1) replace the 1-in. tubing with a larger line with more heat capacity — this will make it harder to boil away the water; 2) use electric tape, which produces just enough heat to prevent freezing, albeit with higher energy cost; 3) use hot water tracing instead of steam; and 4) “bundle” pipe so that several pipes can be traced at the same time, thus sharing the heat. We solved such a problem by using hot water in place of steam. Dirk Willard, senior process engineer Ambitech Engineering, Hammond, Ind. PROTECT PUMPS • • • • Dry Running Cavitation Bearing Failure Overload • Best Sensitivity COMPACT EASY MOUNTING • Starter Door • Panel • Relay Outputs MODEL PMP-25 • Adjustable Delay Timers 4-20 MILLIAMP ANALOG OUTPUT UNIQUE RANGE FINDER SENSOR • Works on Wide Range of Motors • Simplifies Installation • Raceway • Wall >> MAY’S PUZZLER TRUE POWER LOAD DISPLAY TWO ADJUSTABLE SET POINTS CALL NOW FOR YOUR FREE 30-DAY TRIAL 888-600-3247 A self-priming slurry pump circulates hot slurry through a salt mine several hundred feet below the surface of the plant (Figure 1). Steam is injected into the discharge line to help dissolve the salt — the solution being pumped is above saturation; the pump operates with a low NPSHA/ NPSHR. The pump is designed to run dry for long periods of time. Unlike its predecessor, it hasn’t performed reliably. With the discharge diaphragm valve throttled full open, the pump produces a little noise. The pressure gauge bounces wildly but settles in. Throttling back the valve to its operating point causes the pump to scream. We frequently replace the seals and bearings. During the pump’s installation, the suction diameter was increased to provide more NPSH, new expansion joints were put in, as was a new partial open impeller to replace the fully-open impeller. Operating conditions also have changed. To boost the profitability of the plant, the total dissolved solids’ level has been increased by 10%. How can we improve the performance of this pump? Send us your comments, suggestions or solutions for this question by April 11, 2008. We’ll include as many of them as possible in the May 2008 issue and all on CP.com. Send visuals — a sketch is fine. E-mail us at ProcessPuzzler@putman.net or mail to Process Puzzler, Chemical Processing, 555 W. Pierce Road, Suite 301, Itasca, IL 60143. Fax: (630) 467-1120. Please include your name, title, location and company affiliation in the response. And, of course, if you have a process problem you’d like to pose to our readers, send it along and we’ll be pleased to consider it for publication. WWW.LOADCONTROLS.COM www.chemicalprocessing.com http://www.deltacooling.com http://www.deltacooling.com http://CP.com http://WWW.LOADCONTROLS.COM http://www.chemicalprocessing.com

Table of Contents Feed for the Digital Edition of Chemical Processing - March 2008

Chemical Processing - March 2008 Contents From the Editor ChemicalProcessing.com Field Notes In Process Energy Saver Compliance Advisor Distillation is Bubbling Feel Secure About Vulnerability Assessments The Door Opens For Membranes Achieve Effective Heat Exchanger Control Epoxy Maker Finds the Right Glue for Its Business Process Puzzler Plant InSites Equipment & Services Product Spotlight/Classifieds Ad Index End Point

Chemical Processing - March 2008

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.