The article discusses the latest Science and Engineering Indicators 2010 report released by the U.S. National Science Board. Some key points: 1) Worldwide R&D expenditures in 2007 totaled an estimated $1.1 trillion, with the U.S. accounting for about 33% and the top five performers (U.S., Japan, China, Germany, France) representing 66% of global R&D spending. 2) Four-fifths of global R&D is concentrated in just ten countries, showing R&D activity remains heavily concentrated in a few high-income nations and regions. 3) The report provides data on science, engineering, and technology trends in the U.S.

1. February
2010
Energy
Audits
Page 34
www.che.com
2
Distillation trouble shooting • energy auDits
Page 26
VFDs for
Supercritical
Centrifugal Pumps
Co2
Simulation
Software
Focus on
Smart
Mixing
Actuators
Vol. 117 no. 2 february 2010
Positive
Displacement
Pumps

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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 nation
Cover story or region gives to
advancing science
26 Cover Story Kettle Trouble- and technology rela-
shooting Here's 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 globe
news departments
11 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. . 49
15 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 March
19 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 Energy
engineering nations; and more Savings in Regenerative
24 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; News
38 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; Facts
44 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. © 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. 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
L
PublisHEr 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 2010
Publisher Art Director/ report. Produced every two years by NSB — the governing body for
morourke@che.com Editorial Production Manager
dwhitcher@che.com the National Science Foundation (NSF; Arlington, Va.; www.nsf.gov) and
EditOrs
PrOductiON NSF’s div. of Science Resources Statistics — the Science and Engineering
rEbEkkAH J. MArsHAll
Editor in Chief MicHAEl d. krAus Indicators Series is an authoritative source of U.S. and international data
VP of Production & Manufacturing
rmarshall@che.com
mkraus@accessintel.com
on science, engineering and technology. The NSF likens the publication to
dOrOtHy lOzOWski stEvE OlsON a report card on U.S. science, engineering and technology, comparing U.S.
Managing Editor
dlozowski@che.com
Director of Production & performance with other nations. For the broader, global context of CE’s
Manufacturing
GErAld 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), and
gondrey@che.com Ad Production Manager
jcooke@accessintel.com
therefore, the innovation platform on which our profession rides.
scOtt JENkiNs
Associate 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. The
cONtributiNG 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 siErrA
cbutcher@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.com
pgrad@che.com four performers are Japan (13%), China (9%), Germany (6%) and France
tEtsuO sAtOH (Japan) JOHN rOckWEll
tsatoh@che.com Vice President, (4%). NSB’s report puts that in perspective by noting that the top two
JOy lEPrEE (New Jersey)
Audience Development Chemical countries account for around 47% of the global R&D total, while the top
jrockwell@accessintel.com
jlepree@che.com
sArAH GArWOOd
five countries represent about 66%. When the report factors in the next
GErAld 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 bEst
EditOriAl
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 upset
JOHN cArsON GEOrGE sEvEriNE
Jenike & 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 period
MixTech, Inc. JEN fElliNG 1996–2007. At the same time, comparable R&D growth rates of the Asia-8
MukEsH dOblE List Sales, Statlistics (203) 778-8700
IIT Madras, India j.felling@statlistics.com (China, India, Japan, Malaysia, Singapore, South Korea, Taiwan and
HENry kistEr cONfErENcEs Thailand) economies often exceeded 10%, and in China’s case approached
Fluor Corp. dANA d. cArEy 20%. Meanwhile, both India and Brazil are in the report’s top-15 R&D
Director, Global Event Sponsorships
trEvOr 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 research
GErHArd krEysA (retired)
DECHEMA e.V. Senior Manager, publications with authors in Asia are relatively more heavily concentrated
Conference Programming
rAM rAMAcHANdrAN psim@chemweek.com in engineering (China at 16%, Japan at 11%, and the Asia-8 at 19%) than
BOC
bEAtriz suArEz those with authors in the U.S. (7%) or the European Union (8%), where
Director of Conference Operations
iNfOrMAtiON
bsuarez@chemweek.com
focus instead leans toward medical research.
sErvicEs
rObErt 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 currency
cHArlEs sANds
Senior Developer briAN NEssEN conversion to a standard international benchmark and provides a way to
Web/business Applications Architect Group Publisher adjust for differences in the sizes of national economies. In 2007, Israel
csands@accessintel.com bnessen@accessintel.com
had the highest R&D intensity (4.7%), followed by Sweden (3.6%), Finland
HEAdquArtErs
(3.5%), South Korea (3.5%), Japan (3.4%), Switzerland (2.9%) and Iceland
110 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 the
EurOPEAN 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 since
Tel: 49-69-2547-2073 Fax: 49-69-5700-2484
then, U.S. President Barack Obama set a R&D intensity
circulAtiON 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 certainly
Northbrook, IL 60065-3588 email: clientservices@che.com
fall on the back of stimulus packages. Industry’s prolific
AdvErtisiNG rEquEsts: see p. 54
cost-cutting programs have only recently begun to subsub-
For photocopy or reuse requests: 800-772-3350 or info@copyright.com
For 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. 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
S
Circle 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. Calendar
NORTH AMERICA
Pittcon 2010. Pittsburgh Conference on Analytical
Chemistry Applied Spectroscopy (Pittsburgh, Pa.).
Phone: 412-825-3220; Web: pittcon.org
Orlando, Fla. Feb. 28–March 5
Biopharmaceutical Development Production
Week (“Five Conferences In One”). IBC Life Sciences
(Westborough, Mass.). Phone: 800-858-4881;
Web: ibclifesciences.com/courses
Carlsbad, Calif. March 1–5
Global Plastics Engineering Conference 2010.
Society of Plastics Engineers (Lindale, Ga.). Phone:
706-238-9101; Web: sperecycling.org
Orlando, Fla. March 8–10
23rd Conference of the Organic Reaction
Catalysis Society. Organic Reactions Catalysis Soc.
(Devens, Mass.). Phone: 805-313-5237; Web: orcs.org
Monterey, Calif. March 14–18
Corrosion 2010. NACE International (Houston). Phone:
281-228-6213; Web: nace.org
San Antonio, Tex. March 14–18
Circle 8 on p. 54 or go to adlinks.che.com/29247-08
DCAT Week 2010. Drug, Chemical Associated
Technologies Assn. (Robbinsville, N.J.). Phone:
609-448-1000; Web: dcat.org
New York, N.Y. March 15–18
The 2010 National Symposium on Market
Transformation. American Council for an Energy-
Efficient Economy (Washington, D.C.). Phone:
202-507-4000; Web: aceee.org/conf/mt10/index.htm
Washington, D.C. March 16–18
Secrets of Batch Process Scaleup. Scientific Update
Conferences (Mayfield, U.K.). Phone:+44 1435 873062;
Web: scientificupdate.co.uk
Atlanta, Ga. March 17–19
Spring 2010 National Meeting Expo. American
Chemical Soc. (Washington, D.C.). Phone: 800-251-8629
(domestic); Phone: 508-743-0192 (international);
Web: acs.org
San Francisco, Calif. March 21–25
NPRA Annual Meeting. National Petrochemical
Refiners Assn. (Washington, D.C.). Phone: 202-457-0480;
Web: npra.org
Phoenix, Ariz. March 21–23
Odors and Air Pollutants 2010. Air Waste Manage-
ment Assn. (Pittsburgh, Pa.) and the Water Environment
Federation (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. 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:
China's 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 Shelley
2010 Springp. 54 or go to adlinks.che.com/29247-10
Circle 10 on Spring Meeting 6th Global
8 Chemical Engineering www.che.com February 2010

11. Circle 11 on p. 54 or go to adlinks.che.com/29247-11

12.     
 
Powder Inlet
Liquid Inlet
Completed
Dispersion
An intense vacuum draws powders including silica, SLIM eliminates the clogging and poor dispersion quality
thickeners and pigments into the mix chamber of the associated with eductor-based systems. It also eliminates
SLIM 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 easily
and dispersed instantly. serves multiple process lines.
      
 
    
  
 
     
   
 

Circle 12 on p. 54 or go to adlinks.che.com/29247-12

13. Edited by Gerald Ondrey February 2010
Heat and
Tryout set for biomass- power
to-gasoline process Pyrolysis
Solid Fast
A 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 reclamation
envergenttech.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 the
and Ensyn Technologies Inc. (Ottawa, Ont.; used for fuel. The residence time is about 2 s. oil-and-gas industry was
www.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 venture
about 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 Creek
mal 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 bear
waste, 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 proprietary
and sorghum (diagram). In the RTP step, The project is being funded by a $25-million forward-osmosis-membrane
biomass is rapidly heated by hot sand to ap- grant from the U.S. Dept. of Energy (DOE, technology, which separates
proximately 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 by
Lignite-fired power plant osmosis. The concentration
difference across the mem-
uses activated carbon to capture mercury brane (needed for osmosis)
is supplied by concentrated
W 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 processes
capture has been started up near Frank- a rate of up to 10 lb/million acf of gas and wastewater at rates of more
lin, Tex., by Luminant (Dallas, Tex.). In its is subsequently collected on a fabric filter, than 100 gal/min. in field
initial 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 less
removal, 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 required
www.fluor.com), which built the plant. This for fluegas treatment, with the injection of 20 truckloads to transport
meets the limit of 9.2 lb per trillion Btu for halogen (CaCl2) directly onto the coal feed the waste to distant disposal
Hg 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 mineral
coals 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 a
Brown. This problem may be overcome by of PAC at the Newmont plant has been re- new mineral in northwest
using 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 number
on p. 54, or use the website designation. ChemiCal engineering www.Che.Com February 2010 11

14. C hementato R
Scaleup 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) is
pilot plant to produce a new cement known lower temperatures than that used in con- a sulfosalt, which are sulfur
as 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-orange
of Celitement when it starts operating in CO2 emissions, says the company. The pro- mineral consists of very fine
2011, 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 could
to-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 of
with a second silicate component and trans- Celitement enables easy control of harden-
A more robust sensor
formed into Celitement — a hydraulically ing and product quality, with good durabil- Pressure sensors used in ex-
treme service, such as those
active calcium hydrosilicate — by a reac- ity and resistance due to highly connected
used for monitoring drilling
tive milling process. Additives can be used silicate building units and low porosity. operations, can typically only
withstand temperatures of
Printed 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 Microelectronic
A 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 handle
semiconducting 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 mounted
man, Okla.; www.swentnano.com) has de- corporated its nanotubes into an ink formu- on a monocrystalline-silicon
veloped a scalable technique (CoMoCAT lation that allows them to be printed as thin wafer, IMS’ device is mounted
process) 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 occurs
cobalt and molybdenum catalyst that gives tures (100ºC) and leaves no residue. at higher temperatures). The
device — composed of the
rise 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 storing
to generate SWCNs that are semiconducting- uses in various printed electronics applica- measurement and calibration
enriched (90% versus 66% industry average) tions, such as flexible circuits, sensors, dis- data) — can theoretically
or metallic-enriched (50% versus 33% indus- plays, radio-frequency identification tags withstand temperatures up to
try 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 benzenes
P 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% yield
www.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 the
the 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 their
compound has a strong absorption peak whereby 4,4’-bis(trimethylstannyl)biphe- procedure will enable the control of the
at 340 nm and fluoresces yellow-green nyl and [PtCl2(cod)] (cod=1,5-cyclooctadi- thickness, length and twisting degrees
light at around 540 nm — properties ene) first react to form a square-shaped of CNTs.
12 Chemical Engineering www.che.com February 2010

15. (Continued from p. 15)
C hementato R
Story Name (Continued from p. 15)
Headspace and
gas release
Microbubble generator enhances
performance of airlift bioreactor
A 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
region
from 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 to
formance of air-lift loop bioreactors (ALBs). steady-state flow. Other
Up to 18% less energy is consumed for mi- applications for the bub-
crobubble generation compared to conven- ble generator being inves- Riser
tional sparging systems, and the smaller tigated with industrial
bubbles (20 µm versus 1–3-mm dia.) lead partners include aeration
to a 50-fold increase in mass transfer rates, in wastewater treatment;
says Will Zimmerman, a professor at the flotation to remove solids
Dept. of Chemical and Process Engineering, from wastewater; ozone
University of Sheffield. dosing in plasma micro- Groved
The device consists of a fluidic jet-deflec- reactors, oxidation reac- nozzle bank
tion amplifier — a stack of PMMA (poly- tions; and CO2-dosing Gas from oscillator outlets
methylmethacrylate) plates with laser- for growing microalgae
milled 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 membrane
and 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) and
the prongs then pass through a micro-ma- bubbles — with dosing of just one hour per the Korea advanced institute
chined 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, which
Vitrification makes a product from rice husk waste corresponds to the b-axis di-
mension of a single mFi unit
I 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 to
of 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 the
thanks 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 higher
Malaysia (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. The
various countries to achieve the vitrification a preheated brass cylindrical mold and reduced crystal thickness also
of solid waste. It has been shown that for- immediately transferred into an electri- facilitates diffusion, thereby
mation 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 coke
of 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. The
contains 80–95% silica, so vitrification can The glass-ceramic thus prepared had
scientists believe the synthesis
be achieved without any additives. Re- good mechanical properties, including approach — which involves
search-team member Wan Azlina Ab Karim a hardness of 23 MPa and compressive crystallization in bifunctional
Ghani says the group selected crystabollite strength of nearly 20 MPa. Its low density surfactants — could be applied
as 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. C hementato R
Level control
Dresser Masoneilan (Hous-
ton; www.dressermasoneilan.
com) has launched what is
Seal 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 elastomer
polymers 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 Series
equipment show that the seals are prone technology at PPE. The 12-mo tests have combines global level control
to significant swelling, which leads to fail- shown that: conventional NBR elastomers and low- and high-level switch
ure in valves and other equipment, accord- can be used within their normal operating functions into a single unit, vir-
tually eliminating the need for
ing 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 features
The 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 compatibility
the presence of water contamination in the prone to a reversal of the rubber curing and an optional 4–20-mA
biodiesel 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 suits
handling 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), the
ment seals, and either maintain their seals gressive than fresh fatty acid methyl ester, New Energy and Industrial
more 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% more
volume is sufficient to fill a 5-ft-dia. weather The generator requires no external power effective in preventing burns and
balloon, which is the first market targeted and can be transported more easily than 15% lighter than conventional
by 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 carbon
production of the PBIS-1000 (portable bal- that demanded by military and meteoro- into Technora fiber — Teijin’s
loon 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 producing
in 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 working
tion vessel, into which are placed two 32-oz ucts of the chemical reaction are non-toxic, toward the development of other
cans of aluminum powder. A hand-pump in- says the manufacturer. fabrics with enhanced proper-
ties, such as electric conductiv-
ity, electromagnetic shielding
Oxygen 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 by
developed a new spiral-wound membrane dip-coating PS support membranes into Biomass gasification
module 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 Technology
in 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 conditional
Center’s director, professor Shulan Ji, the noted that casting solution concentration,
$22.6-million DOE grant for their
fuel required to generate one 1 GJ of heat coating time and coating speed greatly in-
project to construct a biomass
decreased from 28 kg to about 26.3 kg when fluence the membrane performance. gasifier at Rentech’s Energy
using 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-cane
dimethylsiloxane (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 processed
method. 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. 100
Supercritical
region
Technology Showcase 80
Pc CP
SUPERCRITICAL CO2:
Pressure, bar
60 Liquid
Solid Gas
A 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 region
M
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- pressure
involve 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 132.5 112.8
issues, organic solvents can pose a greater penetration into porous
Benzene 289.0 48.9
number of environmental concerns, solids. Because of its liquid-like
such as atmospheric and land toxic- density, a supercritical fluid’s Carbon dioxide 32.1 73.8
ity. In many cases, conventional or- solvent strength is comparable Cyclohexane 280.3 40.7
ganic solvents are regulated as vola- to that of a liquid. Ethane 32.2 48.8
tile organic compounds (VOCs). In The critical temperatures
Ethylene 9.3 50.4
addition, certain organic solvents are and pressures of materials vary
under restriction due to their ozone- quite significantly (Table 1). Isopropanol 235.2 47.6
layer-depletion potential. Generally, substances that are Propane 96.7 42.5
Supercritical carbon dioxide is an very polar at room temperature Propylene 91.9 46.2
attractive alternative in place of tra- will have high critical tempera-
Toluene 318.6 41.1
ditional organic solvents. CO2 is not tures since a large amount of
considered a VOC. Although CO2 is energy is needed to overcome Water 374.2 220.5
a 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 of
cess, and then returned to the envi- attraction in a supercritical fluid is the fluid. CO2 leaves a lower amount
ronment, it does not contribute to the counterbalanced by the kinetic energy. of residue in products compared to
greenhouse 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 in
and 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 an
properties 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 pressure
tial 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 CO2
Above 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-weight
ger 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