Big Pots and Pans

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Chemical reactors come in a variety of designs. Ordinarily, they range from bullet shaped pressure vessels to a pipe for plug flow reactions to a variety of cylindrical vessel designs.  A big metal reaction vessel has several names- a pot, kettle, or reactor. Reactors can be customized with add-on components to suit specific requirements for agitation efficiency. Reactors can be used for continuous reaction as in the case of a CSTR, or for batch and semi-batch operations.  Custom reactors may be built to provide unique performance specifications.

General purpose reactors can be purchased new or used. They come in a variety of materials of construction. Glassed reactors have a layer of vitreous glaze on the interior walls- often blue in color- and are resistant to corrosion, but may be harmed by thermal shock or electrostatic discharge.

Steel and stainless steel reactors come in a variety of alloy compositions. Hastelloy reactors can be acquired for enhanced resistance to corrosive materials, but at a steep price premium. Vessels with various types of cladding are available- Zr, Ni, Ti, Monel, Inconel, Hastelloy, Cupro Nickel.  It is possible to obtain titanium or tantalum condensers for pots with particularly harsh duty.

Processes that require highly specialized materials of construction are usually more expensive. This can put considerable constraints on the process economics, since it is desirable to have the product requiring the specialized materials pay off the extra costs in a reasonable time period. This pay-off is in the form of a product price premium and/or depreciation. Taking on a project requiring specialized equipment often requires the cost analysis skills of an engineer to throw together a business case study. Perry’s Chemical Engineers Handbook is an excellent resource for this kind of activity.

Agitators are a very important part of the reaction vessel system. Motors, gear boxes, and impellers of various performance specs can be mixed and matched for projected requirements. Impellers are power absorbing implements. They absorb power from the drive motor. The job of an impeller is to dump the required number of watts per kilogram of solution into the reaction mixture to provide satisfactory shear. The energy required depends upon the geometry of the impeller and the density and viscosity of the mixture.

When trying to simulate a reaction on the bench top, it is critical to reproduce the big reactors shear at the smaller scale. Very often, this means that the rpm must be adjusted upwards to get the proper energy transfer. A great resource for this kind of work is the Pilot Plant Real Book, by Francis McConville.

America’s Cold Civil War.

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Note: The following has been determined to be a diatribe and not a screed. A screed would be several times longer.

This period in US history contains enough meat on the bone to keep both scholars and crackpots gnawing for decades. Collectively, we are in the overlap space of a sociological Venn diagram. The overlapping domains of economic calamity, political paranoia, shrinking international stature, and withering military expense combine like cyan, magenta, and yellow to form a white hot zone of malcontent.

It is no overstatement to say that many if not most Americans have chosen a part of the political pool they want to swim in. Listen to the voices at McCain/Palin rallys. Listen to people being interviewed upon leaving a McCain/Palin rally. They’re invariably angry and fearful. They distrust the “Liberal Media”. Do they mean to include Rupert Murdoch’s media empire? Do they also include most of the AM band talk radio programs? Is this the deep end of the pool or the shallow end?

I cannot help but conclude that conservatives are a fearful bunch. Study the McCain/Palin campaign advertising. Go back to any recent presidential campaign and recall Willie Horton or the Swift Boat attack on the democrats. Fear is the unifying ingredient in conservatism and the people who run the GOP machine know how to swing this stick.  Democrats do the Fear theme poorly and as a result, cannot summon the same kind of existential panic that the GOP can pull from their bag of tricks.

McCain is starting to see some of the visceral response to the possibility of Obama as president from underneath all of the rocks and behind all of the tarpaper shacks in the political back-40 acres. He has been openly challenged by angry citizens about the viability of his campaign.

That cartoon figurehead of the GOP, Rush Limbaugh, was practically apoplectic in his frustration with McCain. Strangely, this political freakshow impressario is now towing the line on McCain and has focused his leagions of ditto-zombies on bringing down the reputation of Obama with a mezmerising whisper campaign of slander.

I’m beginning to think that McCain wouldn’t be the worst kind of GOP president to have, especially if the conservatives of the land are this uncertain of him. But Palin as runner-up to the Whitehouse leaves me speechless. A country so brain-addled as to put Palin in national office is perhaps a country that needs to have its nose rubbed in it for a taste of its own collective stupidity. McCain/Palin in Washington may be what it takes for the complete implosion of the GOP.

Having watched the rise of Bush II and the conduct of the 2008 campaign, I have begun to understand what it might have been like to have lived in the period leading up to the American Civil War. This was a period intense division between citizens regarding deeply held beliefs. Civil and religous laws were invoked by both sides to justify their actions. Both Lee and Sherman believed that they marched in righteousness. It was brother fighting brother with a kind of hostility that is startling to people even today.

I sense a widespread and internal hostility along with a rigid adherence to doctrine that marks a divided country. I believe that America is in a type of cold civil war. There is a fulmination of anger and frustration out there that is beginning to partition the meaning of America into distinct translations that suit the adherents. 

Countries that experience economic and political upset are prone to the surfacing of latent fascism. Fascism is a kind of fever that spreads through the vectors of blame and jingoism. Anti-intellectualism and ethnic hatred are common manifestations of a country having a bout of fascism fever.

Witness the accusations of “elitism”  and the whisper campaign questioning the citizenship and religious affiliation of Obama. We have elite military forces, elite police forces, and elite athletes- why not elite chief executives? Why would we demand that politicians be just like the down-home folks like you see, say, running the Tilt-O-Whirl at the carnival? Don’t we want the chief executive to be someone who has honed his skills for public life? The Army has its War College. Why can’t the executive branch have its Administration school?

I think we have a civil cold war brewing in the USA right now and if 20-25 % of the workforce loses its paycheck because of the banking fiasco, I think there’ll be trouble. But no doubt, the DHS has thought of this and has soldiers and Darkwater contractors ready to deal with the sh**storm.

The art of the tip

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Savoir faire is one of those ethereal attributes that a lucky few are born with and something that most of the rest of us have to constantly work on. The world of sales and business development folk very often involves a business dinner in a fine dining establishment. Very often dinner is a prelude to the next days work, so dining is a great opportunity to get to know the customer.  

It is important to realize when taking a potential client out for dinner, one is very much under inspection. A client can be put off in many ways. Poor table manners, boorish behavior, poor listening skills, and shabby taste in restaurants can turn the dinner from a plus plus into a minus minus.

Here is how you make a big impression on a client. I learned this from a professor at Denver University’s hotel & hospitality school. Go to the restaurant the day before and meet the maitre d’. You introduce yourself and explain that you have an important engagement the next night. Give him/her a business card and a several $100 bills. Explain that you want to be addressed by name as you enter the restaurant.

Next, you find the waiter and repeat the instructions. You want to be greeted by name as you are seated. You don’t want their life story, you just want them to be efficient and scarce. Finally, you go into the kitchen and greet the chef. Explain that the next evening is important and ask if he/she has any items that are not on the menu. Thank the chef profusely and go about your business.

The next evening after dinner, overtip the staff. Throwing around a few hundred dollars will get peoples attention and should get you a better table and better service. Doing it ahead of time invests the staff in the gig and will be gratefully appreciated.

I couldn’t help but reprint this list of Tips on Tipping from Bruce Feiler at Gourmet.com. His 3 page essay on learning how to get a table in a posh restaurant and how to tip in advance is quite well written and should encourage the socially inept to give it a try.  Remember, don’t fumble with your wallet fishing for a crumpled note. Have the note neatly folded and ready for a discrete handoff. Show a little style for cryin’ out loud.

Tips on Tipping

  1. Go. You’d be surprised what you can get just by showing up.
  2. Dress appropriately. Your chances improve considerably if you look like you belong.
  3. Don’t feel ashamed. They don’t. You shouldn’t.
  4. Have the money ready. Prefolded, in thirds or fourths, with the amount showing.
  5. Identify the person who’s in charge, even if you have to ask.
  6. Isolate the person in charge. Ask to speak with that person, if necessary.
  7. Look the person in the eye when you slip him the money. Don’t look at the money.
  8. Be specific about what you want. “Do you have a better table?” “Can you speed up my wait?” A good fallback: “This is a really important night for me.”
  9. Tip the maître d’ on the way out if he turned down the money but still gave you a table.
  10. Ask for the maître d’s card as you’re leaving. You are now one of his best customers.

The Hapless Mr. Bush, Prince of the Whig Party.

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The rhyme of history is ringing in my ears. An obscure, slender figure (sans stove pipe hat) has arrived from Illinois amidst the shattered remains of the Whig party.  Alright, that’s an exaggeration.

Our do-nothing, know-nothing warrier prince is nowhere to be seen. The Republican Paradigm, under the leadership of its very own cartoon character- Dubya- has had the misfortune of leaving its greasy fingerprints all over the collapsing financial system. And it’s not just politicians who have left their grubby smudges all over the shards of Grandma’s bone china. It includes the rank & file junior plutocrat-wannabe’s and MBA greedheads under the cloak of the GOP who have gamed the system with zero regard for its stability.

The great benefit of Laissez Faire as a moral philosophy is that one is excused from moral culpability. Nobody expects you to behave honorably because morality is orthogonal to the market. There is no overlap. You are expected to be self-centered and greed is just the normal operating condition. It’s all good, baby.

Mr Bush has not stepped forward to offer advice or reassurance to the citizenry. Bush is brave when he can order the Army to march in somewhere. But if the problem involves math, lookout.   And where is Mr Rove, Bush’s brain? I suppose he is absent because he is a specialist in election, not governance. He just delivers these disasters to the Whitehouse. He evidently holds little or no indemnity for his work.

Instead, this ideological weasel, this scoundrel-in-chief, is hunkered down out of sight during the election so as to avoid contaminating McCain/Palin with the foetid stink of GOP incompetence.

The framers of the constitution apparently never anticipated that the republic could be run aground by a frat-boy imbecile egged on by a pack of greedy, morally vacuous, shady characters from the military-industrial-finance-fundamentalist “sector”. 

The US constitution needs a provision for mid-term ejection of incompetent fools.

LoC Readers Predict 2008 Nobel Prize in Chemistry!

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Two reader/commenters who contribute sage commentary to this blog have predicted the 2008 Nobel Prize in Chemistry– Jordan and Hap. Both predicted that Roger Tsien should or would win. Well done!

Naturally, Th’ Gaussling allowed his clairvoyance to be fogged over by sappy sentimentality for the (n+1)th time. My hat is off to these two savants and their predictve powers.

Oh yes, congratulations are in order for the 3 prize winners as well- Osamu Shimomura, Martin Chalfie, and Roger Tsien. Golly, we can’t forget them.

Continuous Synthesis

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One of my great enthusiasms is the topic of small scale continuous synthesis. There has been some new thinking in this area recently. I don’t mean the use of robots to move material around- I mean continuous flow reactions. Our refinery friends have been doing this for a long time. It’s the reason gasoline isn’t $25/gallon. 

Many, if not most, supplies of bulk raw materials come from continuous process equipment. The economies of large scale may require custom reaction equipment dedicated to a given product. The problem for small scale production is the cost of custom designed equipmet is often large compared to the value of the production run. It is usually best to develop processes to operate in conventional, off-the-shelf pots & pans.

The availability of stirred tank reactors and their ease of use for small scale production has dominated the mode of specialty chemical process technology to the present day. Generations of chemists and engineers in fine and specialty chemicals know nothing other than batch reactor chemistry.

Easy, inexpensive continuous processing isn’t automaticaly suitable for every process. Transformations that are suitable for continuous flow processing may still be disqualitied by virtue of upstream or downstream processes that feed from or into transformations that must be done batchwise. There is the question of feed rates to and from the continuous transformative step and the extent to which non-continuous operations are compatible.

But back to basics. Why have continuous synthesizers at all in the small scale?  Why not just run the semi-batch process as may times as you need at the largest scale possible? Well, there is no reason not to. This is a tried and true business plan.  But what small scale continuous processing allows is the possibility of multiple parallel operations run by fewer staff. At the small scale, batch chemical production typically has a larger labor component than bulk or commodity scale production. Improvements to small scale process economics rests to a large extent on reducing the labor cost contribution.

By it’s nature, continuous processing is an intensified activity. The idea is to construct a minimum reactive volume and flow materials through the reaction or processing zone under intensified conditions for as short of a residence time as possible. At any given moment, there is a minimum mass of hazardous materials undergoing a potentially hazardous transformation. Or, intensification may mean the use of smaller ancillary equipment continuously, as in the case of continuous filtration vs batch filtration.

There are those who are making progress in this field. Recently I ran into a number of websites and files of Ashe Morris in the UK. These folks are operating a productive engine of development in regard to reactor design and innovative process chemistry improvemets. They have focused on process efficency and intensification. The question is, what shape will the IP take? Will users pay a royalty on their production or will it be limited to the purchase cost ofthe equipmet. How they do this will make all of the difference to the extent and rate of acceptance in the market.

Nobel Prize Buzz

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It’s that time again. Time for the buzz to start about who gets a trip to Stockholm.  My favorites, in no particular order, are- Bergman, Grey, Whitesides, Kagan, and Mislow. It is a pity that Al Cotton passed on before taking his ride to Sweden.

Naturally, my guess will be wildly off-base owing to my complete ignorance of some seminal work on nano, bio, metalloenzymatic, mRNA, photolabile, surface active, quantum tunneling, neutron activated, antiviral, ionic liquid, quasi-xtal work that has been thrumming along in the basement of Princeton university since Ike was president and known only to 8 people.

Yves Rossi’s Flying Wing

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This is one of the better videos showing details of the technology. I wonder what the stall speed of this thing is. It would be interesting to see what airspeed or pitch attitude limitations he might have when he releases his ‘chute.

The fellows in the second video are experimenting with a different configuration. I suspect they will eventually rediscover the phenomenon of flutter if pitch divergence doesn’t get them first.