That's entrainment

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That's entrainment

  1. 1. February 2010 Energy Audits Page 34 www.che.com 2Distillation trouble shooting • energy auDits Page 26 VFDs for Supercritical Centrifugal Pumps Co2 Simulation Software Focus on Smart Mixing ActuatorsVol. 117 no. 2 february 2010 Positive Displacement Pumps
  2. 2. Fluids thatMove YourWorldIt takes the right fluids to achieve high levels of performance, ™ help maintain winter aviationproductivity and economy. For operating supplies that meet critical safety while contributing to on-time flight departure performance.functional and protection needs in demanding applications, choose www.ucaradf.comfluids from Dow. We supply advanced, proven, and reliablesolutions for heat transfer, lubrication, fluid power, freeze and We stand behind our fluids with a global support team that cancorrosion protection, and deicing. provide the application, technical, regulatory, sales and customer service assistance you require. For fluids that perform, choose ™ † fluids from Dow. increase processing efficiency and economics inhigh temperature processing environments. www.dowtherm.com U.S, Canada, and Mexico: 1-800-447-4369 ™ ™ Latin America: (+55) 11-5188-9222 help prevent system corrosion and freeze damage Europe: +800-3-694-6367* or (+32) 3-450-2240in water-based HVAC, food and beverage, and other systems. Asia-Pacific: +800-7776-7776* or (+60) 3-7958-3392www.dowfrost.com ™ reduce wear and extend the lifeof industrial, mobile, marine and other equipment while offering ®TM Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow †SYLTHERM Fluids are manufactured by Dow Corning Corporation and distributed byimportant fire-resistance and economic benefits. www.ucon.com The Dow Chemical Company *Toll-free service not available in all countries. Circle 1 on p. 54 or go to adlinks.che.com/29247-01
  3. 3. Improve bulk dumping 4 ways with new TIP-TITE™ Dumpers from Flexicon®New TIP-TITE™ Universal Drum Dumper handles New TIP-TITE™ Box/Container Dumper handles New TIP-TITE™ High-Lift Box/Container Dumperdrums from 30 to 55 gal (114 to 208 liter) boxes up to 48 in. W x 48 in. D x 44 in. H (shown) and Drum Dumper discharge into vessels (1220 mm W x 1220 mm D x 1118 mm H) 6 to 10 ft (183 to 305 cm) high, dust-free TIP-TITE™ Dumpers bring newfound efficiencies and cost savings to the age-old task of dumping bulk materials from drums, boxes and containers, redefining this class of everyday plant equipment1 Stop dust 3 Increase reliability Flexicon offers TIP-TITE™ Dumpers in mild steel TIP-TITE™ Dumpers hydraulically raise and Flexicon engineers and builds TIP-TITE™ with durable industrial finishes, with stainless rotate the container, creating a dust-tight seal Dumpers specifically for fail-safe reliability steel material contact surfaces, or in all-stainless against a discharge hood that mates with a under constant use in demanding environ- models finished to food, dairy, pharmaceutical or gasketted inlet port fitted to any receiving vessel. ments—and backs them 100% with a industrial standards. All are available with Flexicon Pneumatic or manual slide gates control flow. performance guarantee. mechanical or pneumatic conveyors, rotary airlock valves or with flanged outlets to feed any process.2 Improve safety 4 Cut cost Most importantly, all are engineered, manufac- Ergonomic concerns of manual methods Smooth, safe, dust-free and reliable operation tured, guaranteed and supported by Flexicon— can be eliminated with controlled, automated improves the efficiency of a repetitive task, your single-source solution for virtually any bulk TIP-TITE™ Dumpers, which incorporate with significant savings in labor and downtime, handling problem. features of stringent global safety standards. maximizing your payback. USA UK +44 (0)1227 374710 sales@flexicon.com AUSTRALIA +61 (0)7 3879 4180 1 888 FLEXICON SOUTH AFRICA +27 (0)41 453 1871 Y-0297 Also available (left to right): Open Chute Drum Dumpers, Open Chute Box/Container Dumpers and High Lift Drum Dump Filling Systems .com See the full range of fast-payback equipment at flexicon.com: Flexible Screw Conveyors, Pneumatic Conveying Systems, Bulk Bag Unloaders, Bulk Bag Conditioners, Bulk Bag Fillers, Bag Dump Stations, Drum/Box/Tote Dumpers, Weigh Batching and Blending Systems, and Automated Plant-Wide Bulk Handling Systems ©2010 Flexicon Corporation. Flexicon Corporation has registrations and pending applications for the trademark FLEXICON throughout the world. Circle 4 on p. 54 or go to adlinks.che.com/29247-04
  4. 4. r es… s in over 5,000 sto ave  o m t ana ge product “We h and popular items in stock keep the most and antdsier to manag make sure e our orders are filled on time ea make i low cash f and automate our paper proces a ses dat o act on be able time and in real t e efficiently and Microsoft Dynamics® ERP helps us work mor and provide better customer serv ice.”Microsoft Dynamics® ERP fits your company and business processes, not the other way around.It gives your people easier access to real-time actionable customer information for betterdecision-making and higher ROI.To learn more about the efficiencies Microsoft Dynamics® ERP can create for your business,go to microsoftdynamics.com/manufacturing Circle 5 on p. 54 or go to adlinks.che.com/29247-05
  5. 5. february 2010 In ThIs Issue Volume 117, no. 2 Commentary www.che.com 5 Editor’s Page Status of World- wide R&D In general, R&D expen- ditures indicate the priority that a nationCover story or region gives to advancing science26 Cover Story Kettle Trouble- and technology rela- shooting Heres proof that tive to other goals. kettle reboilers can behave like The recently released thermosiphons and thereby bot- Science and Engineer- tleneck an entire plant. Under- ing Indicators 2010 stand the mechanism to blame report gives the latest and avoid it with these preven- figures for this indica- tion and troubleshooting tips tor across the globenews departments11 Chementator Demonstration Letters . . . . . . . . . . . 6 plant for a biomass-to-gasoline process; Scaleup for a “greener” Calendar . . . . . . . . 7, 8 cement; Oxygen separation mem- Who’s Who . . . . . . . 25 branes; Seal selection in handling Reader Service and storing biofuels; Hydrogen page . . . . . . . . . . . . 54 from a can; Carbon nanotube production process; Vitrification Economic makes a product from rice husk Indicators . . . . . 55, 56 waste; Lignite-fired power plant advertisers uses activated carbon to capture mercury; and more Product Showcase. . 4915 Newsfront Supercritical CO2: Classified A Green Solvent Carbon dioxide, in its equipment & serviCes Advertising . . . . .50–52 supercritical state, is being used to replace 24D-1 Pump User’s Symposium Preview Advertiser Index . . . 53 conventional organic solvents in chemical (Domestic Edition) The 26th International Coming in marCh processes Pump Users Symposium will be held March19 Newsfront Beyond Plant Design Simu- 15–18 at the George R. Brown Convention Look for: Feature Re- lation software finds use in plant optimiza- Center in Houston. A sampling of products ports on Agglomeration tion, energy reduction and operator train- to be displayed is given, including: Find de- Mechanisms and Process ing projects sign files quickly with this search software; Selection; and Using This pump is available in many size combi- Catalysts for Energyengineering nations; and more Savings in Regenerative24 Facts At Your Fingertips Positive Dis- 24D-2 New Products & Services Oxidizers; Engineering placement Pumps This one-page guide (Domestic Edition) This blower applies Practice articles on covers the essentials of selecting positive rotary screw technology; This laboratory Using a Safety PLC for displacement pumps reactor can handle the pressure; Enforce Process Control; Treat- tighter security with this portable finger- ment Method for Coke-34 Feature Report Doing an Energy print reader; Eliminate static electricity Cooling Wastewater; Audit Some pointers to help you find from surfaces with this air jet system; Drift- and Water Solubility in where energy savings can be found at free dew-point measurement is now por- Hydrocarbons; Focus your plant table; A faster way to evaporate solvent on Analyzers; News38 Engineering Practice Variable Fre- articles on Greenhouse from laboratory samples; A control device quency Drives: An Algorithm for Se- Gases — Mandatory that cuts energy consupmtion lecting VFDs for Centrifugal Pumps Reporting and Outlook for making WFI; and more Using this algorithm, engineers can identify for Practical Reduction the most cost-effective and energy-efficient 47 Focus Mixing Uniformly Techniques; and High- pump-system design blend batches with this Purity Processing; Facts44 Environmental Manager The ‘BIST’ inline mixer; Quickly change at Your Fingertips on In Electronic Valve Actuators Smart mount configurations with Steam Systems; and actuators designed with built-in self-test this modular system; A microchip for mix- more capabilities allow rapid identification of ing immiscible fluids; Side-entry mixers for asphalt agitation; A double planetary Cover: potential downtime and increased overall mixer for viscous materials; and more David Whitcher plant safety ChemiCal engineering www.Che.Com february 2010 3
  6. 6. © 2009 Swagelok Company Contrary to what you may think, we’re much more than a tube fitting company. And we have our obsession with Customer Focus to thank for that. Yes, we’re In addition to tube fittings, known throughout the world for our tube fittings. And yes, we’ve been at it for over 60 years. But when companies are looking harder than ever for greater value, it’s we also make valves, our broad range of products, including orbital welders, modular systems, and a regulators, filters, complete line of hose, that helps us offer more than you expect. See for yourself and happier customers. at swagelok.com/moreproducts. Circle 6 on p. 54 or go to adlinks.che.com/29247-06
  7. 7. Winner of Eight Jesse H. Neal Awards for Editorial Excellence Editor’s Page Published since 1902 An Access Intelligence Publication Status of worldwide R&D LPublisHEr Art & dEsiGN ate last month, in an event at the White House, the U.S. National Sci-MikE O’rOurkE dAvid WHitcHEr ence Board (NSB) released its Science and Engineering Indicators 2010Publisher Art Director/ report. Produced every two years by NSB — the governing body formorourke@che.com Editorial Production Manager dwhitcher@che.com the National Science Foundation (NSF; Arlington, Va.; www.nsf.gov) andEditOrs PrOductiON NSF’s div. of Science Resources Statistics — the Science and EngineeringrEbEkkAH J. MArsHAllEditor in Chief MicHAEl d. krAus Indicators Series is an authoritative source of U.S. and international data VP of Production & Manufacturingrmarshall@che.com mkraus@accessintel.com on science, engineering and technology. The NSF likens the publication todOrOtHy lOzOWski stEvE OlsON a report card on U.S. science, engineering and technology, comparing U.S.Managing Editordlozowski@che.com Director of Production & performance with other nations. For the broader, global context of CE’s ManufacturingGErAld ONdrEy (Frankfurt) solson@accessintel.com audience, the report reveals a number of interesting facts about the pres pres-Senior Editor JOHN blAylOck-cOOkE ent status and future outlook of research and development (R&D), andgondrey@che.com Ad Production Manager jcooke@accessintel.com therefore, the innovation platform on which our profession rides.scOtt JENkiNsAssociate Editor MArkEtiNG In general, R&D expenditures indicate the priority that a nation or re-sjenkins@che.com HOlly rOuNtrEE gion gives to advancing science and technology relative to other goals. ThecONtributiNG EditOrs Marketing Manager hrountree@accessintel.com report estimates that worldwide R&D expenditures in 2007 (the most re re-suzANNE A. sHEllEy AudiENcE cent year for which data is available) totaled an estimated $1,107 billion.sshelley@che.com dEvElOPMENt Even though many countries conduct R&D, for now the lion’s share contin contin-cHArlEs butcHEr (U.K.) sylviA siErrAcbutcher@che.com Senior Vice President, ues to be concentrated in a few high-income countries or regions. The U.S.PAul s. GrAd (Australia) Corporate Audience Development alone accounts for about 33% of the current global R&D total. The next ssierra@accessintel.compgrad@che.com four performers are Japan (13%), China (9%), Germany (6%) and FrancetEtsuO sAtOH (Japan) JOHN rOckWElltsatoh@che.com Vice President, (4%). NSB’s report puts that in perspective by noting that the top twoJOy lEPrEE (New Jersey) Audience Development Chemical countries account for around 47% of the global R&D total, while the top jrockwell@accessintel.comjlepree@che.com sArAH GArWOOd five countries represent about 66%. When the report factors in the nextGErAld PArkiNsON Audience Marketing Director five countries — South Korea, the U.K., the Russian Federation, Canada sgarwood@Accessintel.com(California) gparkinson@che.com and Italy — the total increases to just below 80%, meaning that four-fifths tErry bEstEditOriAl Audience Development Manager of the world’s R&D is concentrated in only ten countries.AdvisOry bOArd tbest@accessintel.com There are a number of trends, however, that predict an inevitable upsetJOHN cArsON GEOrGE sEvEriNEJenike & Johanson, Inc. Fulfillment Manager in the status quo. Consider, for instance, that growth of R&D expendi-dAvid dickEy gseverine@accessintel.com tures in the U.S. and the EU averaged 5–6% annually over the periodMixTech, Inc. JEN fElliNG 1996–2007. At the same time, comparable R&D growth rates of the Asia-8MukEsH dOblE List Sales, Statlistics (203) 778-8700IIT Madras, India j.felling@statlistics.com (China, India, Japan, Malaysia, Singapore, South Korea, Taiwan andHENry kistEr cONfErENcEs Thailand) economies often exceeded 10%, and in China’s case approachedFluor Corp. dANA d. cArEy 20%. Meanwhile, both India and Brazil are in the report’s top-15 R&D Director, Global Event SponsorshipstrEvOr klEtz dcarey@chemweek.com performers and are acknowledged for essentially doubling their R&D ex-Loughborough University, U.K. PEck siM penditures over the past decade or so. Also noteworthy is that researchGErHArd krEysA (retired)DECHEMA e.V. Senior Manager, publications with authors in Asia are relatively more heavily concentrated Conference ProgrammingrAM rAMAcHANdrAN psim@chemweek.com in engineering (China at 16%, Japan at 11%, and the Asia-8 at 19%) thanBOC bEAtriz suArEz those with authors in the U.S. (7%) or the European Union (8%), where Director of Conference OperationsiNfOrMAtiON bsuarez@chemweek.com focus instead leans toward medical research.sErvicEsrObErt PAciOrEk cOrPOrAtE Another basis for the report’s geographical comparisons is R&D inten-Senior VP & Chief Information Officer stEvE bArbEr sity, typically measured as the ratio of a country’s national R&D expen-rpaciorek@accessintel.com VP, Financial Planning & Internal Audit sbarber@accessintel.com ditures to GDP for a given year. This approach does not require currencycHArlEs sANdsSenior Developer briAN NEssEN conversion to a standard international benchmark and provides a way toWeb/business Applications Architect Group Publisher adjust for differences in the sizes of national economies. In 2007, Israelcsands@accessintel.com bnessen@accessintel.com had the highest R&D intensity (4.7%), followed by Sweden (3.6%), FinlandHEAdquArtErs (3.5%), South Korea (3.5%), Japan (3.4%), Switzerland (2.9%) and Iceland110 William Street, 11th Floor, New York, NY 10038, U.S.Tel: 212-621-4900 Fax: 212-621-4694 (2.8%). In comparison, R&D intensity was lower in theEurOPEAN EditOriAl OfficEs U.S. (2.7%), the EU (1.8%) and China (1.5%).Zeilweg 44, D-60439 Frankfurt am Main, Germany In an April 2009 speech and on several occasions sinceTel: 49-69-2547-2073 Fax: 49-69-5700-2484 then, U.S. President Barack Obama set a R&D intensitycirculAtiON rEquEsts:Tel: 847-564-9290 Fax: 847-564-9453 goal of 3%. For the U.S. or any large economy today, how how-Fullfillment Manager; P.O. Box 3588, ever, an increase in R&D intensity would almost certainlyNorthbrook, IL 60065-3588 email: clientservices@che.com fall on the back of stimulus packages. Industry’s prolificAdvErtisiNG rEquEsts: see p. 54 cost-cutting programs have only recently begun to subsub-For photocopy or reuse requests: 800-772-3350 or info@copyright.comFor reprints: chemicalengineering@theygsgroup.com side, and widescale impacts on R&D are flat at best. ■ Rebekkah Marshall ChemiCal engineering www.Che.Com February 2010 5
  8. 8. Letters Comparing petrochemical plant aging The massive buildup of new petrochemical capacity in the Middle East and Asia has been well documented, and its effect on future supply-demand much discussed. But a look at the average ages of plants in different regions in the years that follow this capacity buildup, prompts new conclusions on just how profound the effects of this new capacity will be. Ed Gartner, Director of SRI Consulting’s World Petro- chemicals research program, has examined the aging of ethylene plants through 2015. Gartner’s methodology is to compare the current- and future-average ages of plants in different regions, using 1974 as the base, or “zero” year. The regions themselves are defined by the OECD. They comprise China-India; ME-AF, which stands for Middle East and Africa, but does not include Turkey; Europe, which includes Western Europe plus Turkey, Poland, the Czech Republic, Hungary and the Slovak Republic; and Pacific, which includes Japan, Korea, Australia and New Zealand By 2015, analysis shows that the average life of ethyl- ene plants in China-India and ME-AF will be around 10 years, while the average of plants in North America and Europe will be around 30 years. There are several conclu- sions to be drawn and extrapolations to be made from Gartner’s study: • irst and foremost, plants in the Middle East and F China-India will have an efficiency advantage com- pared with plants in the rest of the world, just because of their age, scale and relatively modern technology • eanwhile, plants in North America, Europe and the M Pacific will be candidates for closure or replacement, unless their efficiency and competitiveness can be im- proved and their lifespan expanded • huttering capacity in North America and Europe is SCircle 7 on p. 54 or go to adlinks.che.com/29247-07 becoming increasingly expensive, mainly because of the requirement to remediate the sites on closure. This may lead to the lifetime of older plants being extended beyond normal expectations and/or their product slates being reformulated • ubstantial investment would be needed to rebuild S older capacity, and apart from national governments and oil majors, it is not apparent who would have the wherewithal to rebuild North American, European and Pacific capacity All of these observations point to a more rapid shift of the petrochemicals industry to the axis between the Mid- dle East and China in the years to come. In the North American, European and Pacific regions, meanwhile, the most likely outcome will be a drive towards added-value products that can serve the domestic markets. John Pearson, President Access Intelligence, Chemical Business Media div. Postscripts, corrections December, Building a Better Dryer: On p. 28, the Website for Drytech should be drytecheng.com not drytechinc.com. ■
  9. 9. CalendarNORTH AMERICAPittcon 2010. Pittsburgh Conference on AnalyticalChemistry Applied Spectroscopy (Pittsburgh, Pa.).Phone: 412-825-3220; Web: pittcon.orgOrlando, Fla. Feb. 28–March 5Biopharmaceutical Development ProductionWeek (“Five Conferences In One”). IBC Life Sciences(Westborough, Mass.). Phone: 800-858-4881;Web: ibclifesciences.com/coursesCarlsbad, Calif. March 1–5Global Plastics Engineering Conference 2010.Society of Plastics Engineers (Lindale, Ga.). Phone:706-238-9101; Web: sperecycling.orgOrlando, Fla. March 8–1023rd Conference of the Organic ReactionCatalysis Society. Organic Reactions Catalysis Soc.(Devens, Mass.). Phone: 805-313-5237; Web: orcs.orgMonterey, Calif. March 14–18Corrosion 2010. NACE International (Houston). Phone:281-228-6213; Web: nace.orgSan Antonio, Tex. March 14–18 Circle 8 on p. 54 or go to adlinks.che.com/29247-08DCAT Week 2010. Drug, Chemical AssociatedTechnologies Assn. (Robbinsville, N.J.). Phone:609-448-1000; Web: dcat.orgNew York, N.Y. March 15–18The 2010 National Symposium on MarketTransformation. American Council for an Energy-Efficient Economy (Washington, D.C.). Phone:202-507-4000; Web: aceee.org/conf/mt10/index.htmWashington, D.C. March 16–18Secrets of Batch Process Scaleup. Scientific UpdateConferences (Mayfield, U.K.). Phone:+44 1435 873062;Web: scientificupdate.co.ukAtlanta, Ga. March 17–19Spring 2010 National Meeting Expo. AmericanChemical Soc. (Washington, D.C.). Phone: 800-251-8629(domestic); Phone: 508-743-0192 (international);Web: acs.orgSan Francisco, Calif. March 21–25NPRA Annual Meeting. National Petrochemical Refiners Assn. (Washington, D.C.). Phone: 202-457-0480;Web: npra.orgPhoenix, Ariz. March 21–23Odors and Air Pollutants 2010. Air Waste Manage-ment Assn. (Pittsburgh, Pa.) and the Water EnvironmentFederation (Alexandria, Va.). Phone: 412-904-6020;Web: wef.org/oap/Charlotte, N.C. March 21–24 (Continues on p. 8) Circle 9 on p. 54 or go to adlinks.che.com/29247-09 Chemical Engineering www.che.com February 2010 7
  10. 10. Calendar 2010 Spring Meeting 6th Global Congress on Process Safety. American Inst. of Chemical Engineers (New York, N.Y.). Phone: 646-495-1360; Web: aiche.org San Antonio, Tex. March 21–25 37th Annual NOBCChE Conference. National Organization for the Professional Advancement of Black Chemists and Chemical Engineers (Washington, D.C.). Phone: 866-544-9677; Web: nobcche.org Atlanta, Ga. March 29–April 2 Molding 2010: Emerging Technologies for Business Success in Changing Global Market. Executive Conference Management (Plymouth, Mich.). Phone: 734-737-0507; Web: executive-conference.com San Antonio, Tex. April 12–14 SynGas 2010. SynGas Assn (Baton Rouge, La.). Phone: 225-922-5000; Web: ay syngasassociation.com Tulsa, Okla. April 19–21 ies ew ustr Europe at ind Second Annual Conference on Ethics and Human ess Values in Engineering. World Federation of Engineer- g oc ing Organizations (Paris). Phone: +34-93-401-1714; r ’s p he Web: icehve.com ina Barcelona, Spain March 2–4 t ch to Understanding Polymorphism and Crystallization Issues in the Pharmaceutical Industry. Scientific a Update Conferences (Mayfield, U.K.). Phone: +44 1435 hin R C 2 010 873062; Web: scientificupdate.co.uk , P ne ing Nice, France March 22–24 eij -4 Ju B 1 Analytica 22nd International Trade Fair. Messe München GmbH/Analytica (Munich, Germany). Phone: Chinas most international +49-89-949-11488; Web: analytica.de event for the chemical process Munich, Germany March 23–26 industries welcomes YOU! Secrets of Batch Process Scale-Up. Scientific • Chemical Apparatus and Update Conferences (East Sussex, U.K.). Phone:+44 (0) Plant Construction 1435 873062; Web: scientificupdate.co.uk • Process Technology Barcelona, Spain April 13–15 • Petrochemistry • Maintenance and Quality Assurance 6th EE and RES Congress and Exhibition. Via Expo • Environmental Protection (Sofia, Bulgaria). Phone: +359-32-960012; Web: viaexpo.com • Water Treatment Sofia, Bulgaria April 14–16 • Pharmaceutical Industry • Biotechnology Asia Elsewhere World CTL 2010 Conference. World CTL (Paris). • Food Industry Phone: +33-1-44-01-8713; Web: world-ctl.com • Agrochemistry Beijing, China April 13–16 • Laboratory and Analytical Techniques • Packaging and Storage Techniques Middle East Plastic Pipes 2010. Applied Market In- • Resources Development formation Ltd. (Bristol, U.K.). Phone: +44 117 924 9442; Web: www2.amiplastics.com/events www.achemasia.de www.achema.cn Dubai, UAE May 17–19 ■ Suzanne Shelley2010 Springp. 54 or go to adlinks.che.com/29247-10 Circle 10 on Spring Meeting 6th Global8 Chemical Engineering www.che.com February 2010
  11. 11. Circle 11 on p. 54 or go to adlinks.che.com/29247-11
  12. 12.        Powder Inlet Liquid Inlet Completed DispersionAn intense vacuum draws powders including silica, SLIM eliminates the clogging and poor dispersion qualitythickeners and pigments into the mix chamber of the associated with eductor-based systems. It also eliminatesSLIM Solids/Liquid Injection Manifold. They are injected the need for an auxiliary pump in most applications.through a ported rotor directly into the high shear zone Operation is simple – and the portable inline SLIM easilyand dispersed instantly. serves multiple process lines.                         Circle 12 on p. 54 or go to adlinks.che.com/29247-12
  13. 13. Edited by Gerald Ondrey February 2010 Heat andTryout set for biomass- powerto-gasoline process Pyrolysis Solid FastA demonstration plant that will produce Upgrading Transport biomass pyrolysis oil fuels transportation fuels from cellulosic bio-mass will be built at Tesoro Corp.’s petro-leum refinery in Kapolei, Hawaii, by Enver- in a circulating transported fluidized-bed re-gent Technologies (Des Plaines, Ill.; www. actor. The biomass is vaporized, then rapidly Water reclamationenvergenttech.com), a joint venture of Hon- quenched, yielding 65–75 wt.% pyrolysis oil, last month, a new water-eywell’s UOP (Des Plaines; www.uop.com) plus char and non-condensable gas, which are reclamation process for theand Ensyn Technologies Inc. (Ottawa, Ont.; used for fuel. The residence time is about 2 s. oil-and-gas industry waswww.ensyn.com). Scheduled to start up in A shortcoming of bio-oils (including the launched by hbC Systems,2014, the plant will convert biomass into pyrolysis oil) is that they contain 10–40% a newly created joint ventureabout 22,000 gal/yr of fuels — mostly gaso- oxygen, versus essentially none for petro- between hydration Tech-line, with a small amount of diesel fuel. leum, as well as a high percentage of water. nology innovations (hTi; The facility will combine Ensyn’s rapid ther- The UOP process deals with these issues Scottsdate, ariz.; www.hti- water.com) and bear Creekmal processing (RTP) technology with UOP’s in a two-stage hydroprocessing strategy. In Services, llC (albany, ore.;hydroprocessing knowhow to process a range the first step, H2 combines with O2 to form www.bearcreekservices.of cellulosic feedstocks, including agricultural H2O, then all the water is removed as vapor. com). The so-called bearwaste, pulp, paper, woody biomass, algae and In the second step, the partially processed Creek green machine in-dedicated energy crops, such as switchgrass oil is upgraded to gasoline and diesel fuels. corporates hTi’s proprietaryand sorghum (diagram). In the RTP step, The project is being funded by a $25-million forward-osmosis-membranebiomass is rapidly heated by hot sand to ap- grant from the U.S. Dept. of Energy (DOE, technology, which separatesproximately 500°C, in the absence of oxygen, Washington, D.C.; www.energy.gov). water from “virtually all con- taminants” as it migrates through the membrane byLignite-fired power plant osmosis. The concentration difference across the mem-uses activated carbon to capture mercury brane (needed for osmosis) is supplied by concentratedW hat is said to be the first grassroots lignite-fueled power plant to use pow-dered activated carbon (PAC) for mercury PAC, with technology supplied by Bab- cock Power Environmental Inc. (Worcester, Mass.). PAC is injected into the fluegas at brine, which is already typi- cally available at well sites. The mobile unit processescapture has been started up near Frank- a rate of up to 10 lb/million acf of gas and wastewater at rates of morelin, Tex., by Luminant (Dallas, Tex.). In its is subsequently collected on a fabric filter, than 100 gal/min. in fieldinitial operation the 800-MWe supercriti- along with other particulate matter. In tests, the green machine re-cal plant has achieved better than 90% Hg contrast, a 242-MWe plant that Fluor com- claimed almost 125,000 gal of reserve pit waste (using lessremoval, says James Brown, director of pleted in 2008 at a Newmont Mining Corp. than 20 gal of diesel fuel),engineering for Fluor Corp. (Irving, Tex.; gold mine near Elko, Nev., combines Br-PAC, which would have requiredwww.fluor.com), which built the plant. This for fluegas treatment, with the injection of 20 truckloads to transportmeets the limit of 9.2 lb per trillion Btu for halogen (CaCl2) directly onto the coal feed the waste to distant disposalHg determined in the permitting process. A to enhance Hg scrubbing. The process, from wells for underground injec-second 800-MWe unit is scheduled to start Babcock Wilcox (Barberton, Ohio), uses a tion, says hTi.up around mid-year. lime spray-dryer absorber and fabric filter Mercury from lignite and sub-bituminous to capture both sulfur and Hg. It reduces Hg A new mineralcoals is generally in the elemental form and emissions to 0.02 lb/GWh. minerologists from the insti-hence more difficult to capture than the The choice and cost-effectiveness of using tute of applied geosciences,oxidized Hg from bituminous coals. Lignite PAC, Br-PAC or halogen fuel additives de- Karlsruhe institute of Tech-and sub-bituminous coals lack the halogen pends on the coal and the emissions limit, nology (KiT; germany; www.compounds that promote oxidation, says says Brown. For example, the consumption kti.edu) have discovered aBrown. This problem may be overcome by of PAC at the Newmont plant has been re- new mineral in northwestusing more PAC or by using a brominated duced by about 50% through the use of Br- iran that may find applica-PAC (Br-PAC) to capture the Hg. The latter PAC alone, and the halogen fuel additive tions in solar cells. approved by the international miner-is more expensive, but the amount of bro- has further reduced Br-PAC consumption alogical assoc. (ima; Van-minated activated carbon required is only by roughly another 50%. He adds that the doeuvre-les-nancy, France;20–50% as much as standard PAC. system at the Luminant plant is capable of The Luminant plant uses conventional using Br-PAC, if the economics justified it. (Continues on p. 12)Note: For more information, circle the 3-digit numberon p. 54, or use the website designation. ChemiCal engineering www.Che.Com February 2010 11
  14. 14. C hementato RScaleup slated for a ‘greener’ cement (Continued from p. 11) www.ima-mineralogy.org)T his summer, Celitement GmbH (Eggen- stein-Leopoldshafen, Germany; www.celitement.de) will begin construction on a to control the hydration and the quality of the final product. The process operates at considerably and named Daliranite after its discoverer, Farahnaz Daliran, the mineral (PbHgAs2S6) ispilot plant to produce a new cement known lower temperatures than that used in con- a sulfosalt, which are sulfuras Celitement. Located at the north cam- ventional routes to Portland clinker (up to compounds with semiconduc-pus of the Karlsruhe Institute of Technology 1,450°C), and therefore consumes about half tor metals. The soft (Mohs’(KIT), the facility will produce up to 100 kg/d the energy with a corresponding reduction in hardness 1–2), red-orangeof Celitement when it starts operating in CO2 emissions, says the company. The pro- mineral consists of very fine2011, using a process first developed at KIT. cess also uses “far less” lime, and the prod- fibers (20 µm dia.), and it is an In the first step, limestone and sand (Ca- uct binding material can be handled just as excellent semiconductor. For industrial purposes, we couldto-Si mole ratio of 0.5–2.0) and water are ordinary Portland cement. Addition of water grow large crystals of Daliran-transformed into calcium silicate hydrates starts the hydration process, and the only ite, says Daliran.in an autoclave operating at 180–210°C and product, calcium hydrate (CaO-SiO2-H2O),10–20 bar. The product is dried, then mixed is formed. The homogeneous composition ofwith a second silicate component and trans- Celitement enables easy control of harden- A more robust sensorformed into Celitement — a hydraulically ing and product quality, with good durabil- Pressure sensors used in ex- treme service, such as thoseactive calcium hydrosilicate — by a reac- ity and resistance due to highly connected used for monitoring drillingtive milling process. Additives can be used silicate building units and low porosity. operations, can typically only withstand temperatures ofPrinted electronics made possible 80–125°C. To enable opera- tion at higher temperatures,by this carbon-nanotube-production process researchers at the Fraunhofer Institute for MicroelectronicA recently commercialized method for with a narrow distribution of diameters in Circuits and Systems (IMS; growing single-walled carbon nanotubes the range of 0.8 to 1.5 nm, Arthur adds, and Dresden, Germany; www.(SWCNs) in large quantities enables their lengths typically 1,000 times the diameter. ims.fraunhofer.de) have developed a pressure sen-use in a downstream process for depositing In a collaboration with Chasm Technolo- sor system that can handlesemiconducting inks onto flexible surfaces. gies Inc. (Canton, Mass.; www.chasmtek. 250°C. Unlike conventional Southwest NanoTechnologies Inc. (Nor- com), Southwest NanoTechnologies has in- sensors, which are mountedman, Okla.; www.swentnano.com) has de- corporated its nanotubes into an ink formu- on a monocrystalline-siliconveloped a scalable technique (CoMoCAT lation that allows them to be printed as thin wafer, IMS’ device is mountedprocess) in which carbon monoxide is decom- films onto flexible surfaces using commer- on a modified wafer of silicon-posed into carbon and CO2 at 700–950ºC in cially available printing processes. A carbon oxide, with the oxide layer pro-a fluidized bed reactor. Growth of the nano- nanotube paste is mixed with an evaporating viding better electrical insula-tubes depends on a specialized proprietary ink component that dries at low tempera- tion (current leakage occurscobalt and molybdenum catalyst that gives tures (100ºC) and leaves no residue. at higher temperatures). The device — composed of therise to high selectivity. Because of its electronic and optical prop- pressure sensor and an EE- CEO David Arthur says the process is able erties, carbon nanotube ink has potential PROM (an element for storingto generate SWCNs that are semiconducting- uses in various printed electronics applica- measurement and calibrationenriched (90% versus 66% industry average) tions, such as flexible circuits, sensors, dis- data) — can theoreticallyor metallic-enriched (50% versus 33% indus- plays, radio-frequency identification tags withstand temperatures up totry average). The method produces nanotubes and others. 350°C, but the researchers have only demonstrated op- eration up to 250°C thus far.Making a ring of eight benzenesP rofessor Shigeru Yamago and col- leagues at the Institute for Chemi-cal Research, Kyoto University (Japan; that may find applications in organic light-emitting diodes (OLEDs), organic conductors and battery electrodes. Pre- platinum-biphenyl intermediate. The planar complex is then separated, and heated with bromine at 95°C. A 25% yieldwww.scl.kyoto-u.ac.jp/~yasuyuki/) have viously, other research groups have syn- of [8]cycloparaphenylene is achieved.synthesized [8]cycloparaphenylene for thesized ring compounds with 9 or 12 The researchers plan to apply thethe first time. The 11-nm-dia. molecule benzenes linked together. technique for synthesizing cylinder-consists of eight benzene molecules The compound is synthesized under shaped materials, such as carbon nano-linked together in a closed chain. The mild conditions in a three-step process tubes (CNTs). Yamago believes theircompound has a strong absorption peak whereby 4,4’-bis(trimethylstannyl)biphe- procedure will enable the control of theat 340 nm and fluoresces yellow-green nyl and [PtCl2(cod)] (cod=1,5-cyclooctadi- thickness, length and twisting degreeslight at around 540 nm — properties ene) first react to form a square-shaped of CNTs. 12 Chemical Engineering www.che.com February 2010
  15. 15. (Continued from p. 15)C hementato RStory Name (Continued from p. 15) Headspace and gas releaseMicrobubble generator enhancesperformance of airlift bioreactorA patented (WO 2008/053174), fluidic-os- cillator-driven device that generates mi-crobubbles has been shown by researchers In a 250-L prototype ALB, the yield of yeast biomass grown with Downcomer regionfrom the University of Sheffield (U.K.; www. microbubble genera-shef.ac.uk/cpe), in collaboration with the tion with fluidic oscilla-Academy of Sciences of the Czech Republic tion was shown to be(Prague; www.cas.cz/en), to improve the per- 15% higher compared toformance of air-lift loop bioreactors (ALBs). steady-state flow. OtherUp to 18% less energy is consumed for mi- applications for the bub-crobubble generation compared to conven- ble generator being inves- Risertional sparging systems, and the smaller tigated with industrialbubbles (20 µm versus 1–3-mm dia.) lead partners include aerationto a 50-fold increase in mass transfer rates, in wastewater treatment;says Will Zimmerman, a professor at the flotation to remove solidsDept. of Chemical and Process Engineering, from wastewater; ozoneUniversity of Sheffield. dosing in plasma micro- Groved The device consists of a fluidic jet-deflec- reactors, oxidation reac- nozzle banktion amplifier — a stack of PMMA (poly- tions; and CO2-dosing Gas from oscillator outletsmethylmethacrylate) plates with laser- for growing microalgaemilled cavities — coupled with a feedback for biofuel production. In the latter exam-loop. Air is supplied to the amplifier cavity ple, microbubbles of CO2 not only dissolve Zeolite membraneand deflected to one prong or the other of a faster, but they also remove O2, which is researchers from osaka Pre-Y-shaped channel, and the oscillation (1–100 toxic to algae, and keep the suspension well fecture university (Japan; www.Hz) is controlled by the feedback loop — a mixed. Algal cultures with the fluidic-oscil- nanosq.21c.osakafu-u.ac.jp),tube of adjustable length between the two lator-generated bubblers had about a 30% Stockholm university (Swe-prongs. The air pulses emerging from one of higher yield than conventionally produced den; www.su.se/english) andthe prongs then pass through a micro-ma- bubbles — with dosing of just one hour per the Korea advanced institutechined nozzle before entering a distributor day with 5 vol.% CO2 in N2 over a two-week of Science and Technology (KaiST; Daejeon; www.kaist.at the bottom of the ALB (diagram). trial, says Zimmerman. edu), have synthesized sheets of ZSm-5 (mFi-type) zeolites that are only 2 nm thick, whichVitrification makes a product from rice husk waste corresponds to the b-axis di- mension of a single mFi unitI n Malaysia, about 2-million metric tons (m.t.) of rice husk are produced each year,and the rice husk is either burned or disposed In laboratory trials, rice husk is first converted to ash by combustion at 500°C for 2 h. This ash is then placed in a re- cell. The sheet structure is said to improve the surface- to-volume ratio compared toof as waste. Now this waste may find appli- fractory alumina crucible and heated to conventional zeolite catalysts:cation as a non-leachable building material 500°C for 1 h in a Carbolite furnace. The the large number of acid sites on the external surface of thethanks to a vitrification process developed temperature is then ramped at a rate of zeolite sheets have been dem-by researchers from the University Putra 10°C/min up to 1,400°C, which converts onstrated to impart a higherMalaysia (Serdang; www.eng.upm.edu.my). the ash into a molten glassy ceramic. catalytic activity for the cracking Several methods have been applied in The melted sample is then poured into of large organic molecules. Thevarious countries to achieve the vitrification a preheated brass cylindrical mold and reduced crystal thickness alsoof solid waste. It has been shown that for- immediately transferred into an electri- facilitates diffusion, therebymation of glass-ceramic upon melting and cal muffle furnace for annealing at 500°C dramatically suppressing cata-quenching can be achieved with the addition for 1 h. The sample is then cooled to room lyst deactivation through cokeof bottom ash or glass wastes into fly ash. temperature and cut into pieces using a deposition during methanol-to-However, Malaysian rice-husk ash already diamond disk. gasoline conversion, says osa- ka’s yasuhiro Sakamoto. Thecontains 80–95% silica, so vitrification can The glass-ceramic thus prepared had scientists believe the synthesisbe achieved without any additives. Re- good mechanical properties, including approach — which involvessearch-team member Wan Azlina Ab Karim a hardness of 23 MPa and compressive crystallization in bifunctionalGhani says the group selected crystabollite strength of nearly 20 MPa. Its low density surfactants — could be appliedas the target crystalline phase of the silicate and high porosity make it suitable for use to make other zeolites with im-formed because of its excellent thermal and as an insulator where its high porosity proved catalytic performance. (Continues on p. 19)mechanical properties. leads to low thermal conductivity. ChemiCal engineering www.Che.Com February 2010 13
  16. 16. C hementato R Level control Dresser Masoneilan (Hous- ton; www.dressermasoneilan. com) has launched what isSeal selection for handling and storage of biofuels said to be the first level instru- ment that integrates level-R esults of 12-mo immersion tests in biodie- sel and bioethanol of a range of elastomerpolymers typically used in fuel-handling ing, or switch to alternative sealing mate- rials, such as peroxide-cured fluoroelasto- mers, says John Kerwin, head of materials transmitter, controller and switch functions into a single device. The 12400 Seriesequipment show that the seals are prone technology at PPE. The 12-mo tests have combines global level controlto significant swelling, which leads to fail- shown that: conventional NBR elastomers and low- and high-level switchure in valves and other equipment, accord- can be used within their normal operating functions into a single unit, vir- tually eliminating the need foring to Precision Polymer Engineering Ltd., parameters for both conventional gaso- additional level switches and(PPE; Blackburn, U.K.; www.prepol.com). line and gasoline-ethanol blends, but they controllers. The device featuresThe swelling is caused by increased acidity suffer significant swelling with biodiesel; smart filtering, HART commu-of the biodiesel due to oxidation. Moreover, bisphenol-cured FKM elestomers that are nication-protocol compatibilitythe presence of water contamination in the prone to a reversal of the rubber curing and an optional 4–20-mAbiodiesel was found to accelerate the rate of process should be replaced with peroxide- analog-output signal.elastomer swelling. cured FKM for biofuel applications; and The research shows that companies the rate of swelling varies, depending on Firefighting suitshandling biofuels need to be aware of the the immersion conditions. For example, Teijin Techno Products Ltd.increased acidity risk of biofuels on equip- aged fatty acid methyl ester is more ag- (Osaka; www.teijin.co.jp), thement seals, and either maintain their seals gressive than fresh fatty acid methyl ester, New Energy and Industrialmore regularly to check for signs of swell- says PPE. Technology Development Org. (NEDO; Kawasaki) and Ho-Hydrogen from a can sokawa Micron Corp. (Osaka; www.hosokawamicron.co.jp)A newly marketed portable reactor system jects water into the vessel, where the alumi- have developed a new fabric that incorporates nanostructure for generating hydrogen is capable of num powder and a mix of proprietary addi- fiber for use in advanced fire-generating 1,000 L of the gas in 20 min. The tives react with the water to generate H2. fighting suits that are 40% morevolume is sufficient to fill a 5-ft-dia. weather The generator requires no external power effective in preventing burns andballoon, which is the first market targeted and can be transported more easily than 15% lighter than conventionalby the system’s manufacturer AlumiFuel high-pressure “K-cylinders.” heat-barrier linings. The nano-Power Inc. (Philadelphia, Pa.; www.alumifu- While the system was designed for bal- structure is made by knead-elpowerinc.com). The company began mass loon inflation in remote locations, such as ing nanoparticles of carbonproduction of the PBIS-1000 (portable bal- that demanded by military and meteoro- into Technora fiber — Teijin’sloon inflation system) last month and ex- logical uses, it may be adapted for other para-aramid fiber. Teijin and Ho-pects to deliver the first units to customers applications requiring portable hydrogen, sokawa Micron aim to establish technology for mass producingin early 2010. such as fuel cells. No greenhouse gases are the fabric for commercial use. The system consists of a cylindrical reac- emitted in the H2 production and the prod- Meanwhile, they are workingtion vessel, into which are placed two 32-oz ucts of the chemical reaction are non-toxic, toward the development of othercans of aluminum powder. A hand-pump in- says the manufacturer. fabrics with enhanced proper- ties, such as electric conductiv- ity, electromagnetic shieldingOxygen separation membranes made in China and heat resistance, by knead- ing different nanoparticles (tita-R esearchers from the Center for Mem- wt.%, 50 wt.% and 75 wt.% ethanol-water nia and silica, for instance) into brane Technology, Beijing University of mixtures and pure ethanol. Then the com- the aramid fiber.Technology (China; www.bjut.edu.cn) have posite PDMS membranes are formed bydeveloped a new spiral-wound membrane dip-coating PS support membranes into Biomass gasificationmodule for use in oxygen-enriched combus- the PDMS casting solution — a mixture of Rentech, Inc. (Los Angeles,tion. A pilot-scale system with five mem- PDMS, the crosslinking agent TEOS (tetra- Calif.; www.rentechinc.com)brane modules has been built and tested ethoxysilane), and the catalyst dibutyltin at and ClearFuels Technologyin a 4-ton, oil-fired boiler. According to the a precise weight ratio in cyclohexane. It is Inc. (www.clearfuels.com) have been awarded a conditionalCenter’s director, professor Shulan Ji, the noted that casting solution concentration, $22.6-million DOE grant for theirfuel required to generate one 1 GJ of heat coating time and coating speed greatly in- project to construct a biomassdecreased from 28 kg to about 26.3 kg when fluence the membrane performance. gasifier at Rentech’s Energyusing O2-enriched air, suggesting energy Membrane modules (4-in. dia, 1-m long) are Technology Center in Denver.savings of at least 5.7%. then made from at least one pair of spaced The gasifier will process 20 ton/d The membranes — a composite of poly- membrane sheets interposed between spaced of wood waste and sugar-canedimethylsiloxane (PDMS) and polysul- porous material sheets. All of the sheets are bagasse into synthesis gas,fone (PS) — are made using a dip-coating in turn spirally wound around an axially which will be further processedmethod. First, PS support membranes are positioned hollow mandrel. The university into liquid fuels. ❏pretreated by sequential immersion into 25 plans to commercialize the technology. ■ 14 Chemical Engineering www.che.com February 2010
  17. 17. 100 Supercritical region Technology Showcase 80 Pc CPSUPERCRITICAL CO2: Pressure, bar 60 Liquid Solid GasA GREEN SOLVENT 40 Legend: CP = Critical point 20 Tp = Triple point Tc Carbon dioxide, in its supercritical state, 0 Tp is being used to replace conventional organic –50 0 Temperature, °C +50 solvents in chemical processes Figure 1. The phase diagram for carbon dioxide shows its supercritical regionM any reactions, extractions, fluid has liquid-like density, it Table 1. Critical conditions separations and other op- exhibits gas-like diffusivity, sur- for various materials erations in the chemical face tension and viscosity. Its Critical Critical process industries (CPI) gas-like viscosity results in high tempera- pressureinvolve the use of organic solvents. mass transfer. Its low surface ture (°C) (bar)In addition to handling and disposal tension and viscosity lead to Ammonia 132.5 112.8issues, organic solvents can pose a greater penetration into porous Benzene 289.0 48.9number of environmental concerns, solids. Because of its liquid-likesuch as atmospheric and land toxic- density, a supercritical fluid’s Carbon dioxide 32.1 73.8ity. In many cases, conventional or- solvent strength is comparable Cyclohexane 280.3 40.7ganic solvents are regulated as vola- to that of a liquid. Ethane 32.2 48.8tile organic compounds (VOCs). In The critical temperatures Ethylene 9.3 50.4addition, certain organic solvents are and pressures of materials varyunder restriction due to their ozone- quite significantly (Table 1). Isopropanol 235.2 47.6layer-depletion potential. Generally, substances that are Propane 96.7 42.5 Supercritical carbon dioxide is an very polar at room temperature Propylene 91.9 46.2attractive alternative in place of tra- will have high critical tempera- Toluene 318.6 41.1ditional organic solvents. CO2 is not tures since a large amount ofconsidered a VOC. Although CO2 is energy is needed to overcome Water 374.2 220.5a greenhouse gas, if it is withdrawn the polar attractive energy.from the environment, used in a pro- At critical conditions, the molecular fine-tuned by adjusting the density ofcess, and then returned to the envi- attraction in a supercritical fluid is the fluid. CO2 leaves a lower amountronment, it does not contribute to the counterbalanced by the kinetic energy. of residue in products compared togreenhouse effect. There have been an In this region, the fluid density and conventional solvents, and it is avail-increasing number of commercialized density-dependent properties are very able in relatively pure form and inand potential applications for super- sensitive to pressure and temperature large quantities.critical fluids. This article summarizes changes. The solvent power of a su- CO2’s critical temperature (Tc;the fundamentals of supercritical CO2 percritical fluid is approximately pro- 32.1°C) is near ambient, making it anproperties and processing, and pres- portional to its density. Thus, solvent attractive solvent for temperature-sen-ents a number of current and poten- power can be modified by varying the sitive materials. CO2’s critical pressuretial applications. temperature and pressure. Because is 73.8 bar (Pc; 1,070 psi), as shown in their properties are a strong function its phase diagram (Figure 1).Supercritical fluids of temperature and pressure, super- CO2 as a solvent. Supercritical CO2Above its critical values, a compound’s critical fluids are considered tunable is a good solvent for many nonpolar,liquid-vapor phase boundary no lon- solvents. In contrast, conventional liq- and a few polar, low-molecular-weightger exists and its fluid properties can uid solvents require relatively large compounds. It is not a very good sol-be tuned by adjusting the pressure or pressure changes to affect the density. vent for high-molecular-weight com-temperature. Although supercritical pounds and the majority of polar com- Supercritical CO2 properties pounds. Uneconomically high process For more-detailed information, including all Unlike many organic solvents, super- pressure may be required to solvate references see: “Supercritical CO2: A Green critical CO2 is non-flammable. It is polar, inorganic or high-molecular- Solvent,” PEP Report No. 269, SRI Consult- ing, Menlo Park, Calif. (August 2009) Author: inert, non-toxic, has a relatively low weight material in CO2. To increase Susan Bell of SRI Consulting; Email: sbell@ sriconsulting.com; Phone: (281) 203-6286. cost and has moderate critical con- the solubility of such compounds in stants. Its solvation strength can be supercritical CO2, small amounts of Chemical Engineering www.che.com February 2010 15

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