Author Archives: R.E. Buxbaum

About R.E. Buxbaum

Robert Buxbaum is a life-long engineer, a product of New York's Brooklyn Technical High School, New York's Cooper Union to Science and Art, and Princeton University where he got a PhD in Chemical Engineering. From 1981 to 1991 he was a professor of Chemical Engineering at Michigan State, and now runs an engineering shop in Oak Park, outside of Detroit, Michigan. REB Research manufactures and sells hydrogen generation and purification equipment. He's married with 3 wonderful children who, he's told, would prefer to not be mentioned except by way of complete, unadulterated compliments. As of 2016, he's running to be the drain commissioner/ water resources commissioner of Oakland county.

Military heroes, Genghis and confederate

1 Reply
genghis-khan-statue-complex

This 13 story statue of Genghis Kahn looks over the plains of Mongolia.

All military statues are offensive, as best I can tell. Among the most offensive, is the 131 foot tall monument to Genghis Kahn in central Mongolia. Genghis Kahn is known for near-perfect military success, and for near-total disregard for non-Mongols; he treated them as cattle, to be herded, slaughtered, raped or pillaged. I imagine this statue is offensive to Chinese, Russians, Koreans, Moslems, Jews, Hindus, Poles, and Germans — people he slaughtered by the millions. For some Mongols too, I imagine this statue is offensive as a sad reminder that Mongolia no longer rules the eastern world. But the monument is not for the maudlin, nor is it intended to offend. Like other military statues, the Genghis monument is a rally point for soldiers, old and new. It’s a way to inspire Mongols to be great leaders of men, military and not. Such will see, in Genghis, a man who made tough choices, and carried through to great achievements. That he killed and oppressed others will be justified by noting he did it to keep his Mongols from being killed or oppressed. The grand size is chosen to encourage Mongols to think big.

Genghis appears in fictional form as the villain, Shan Yu, in Mulan. There, his motivation is he doesn’t like the wall. Mulan and the Chinese army stop his Mongol attack by burying them at a snow-covered mountain pass. Historically, a Chinese army did meet Genghis and his army at a mountain pass, but the Mongols were not defeated. Instead they bypassed the Chinese and captured their supplies. Genghis then offered the starving Chinese a choice: join or die. Those that joined had to fight those who did not. A few months later, Peking fell, and in a few years, the rest of Asia. Few of the turncoats survived. Given the same choice, Genghis’s men never turned on him.

General Lee planted a maple tree on this spot in Fort Hamilton, New York. in 2017 the plaque is removed as it's considered offensive.

General Lee planted a maple tree on this spot in Fort Hamilton, New York. in 2017 the plaque is removed as offensive.

Genghis’s most famous saying is that one arrow is easily broken, but a bundle will overcome any adversary. Similar to this, he is supposed to have said that, if you treat your soldiers as sons, they will follow you even into death. Such words are nonsense to non-soldiers and professional complainers: those who do not imagine themselves going to war. Those who go to war as generals know this is how to behave; those who go as soldiers hope for a leader who values them as sons, and not as cannon fodder.

In the US we’ve begun removing all monuments to the southern forces of the Civil War. This may be a mistake, but it seems irreversible. We’ve kept our monuments for Northern generals including William Sherman, known for his tactic of total destruction, and for Phillip Sheridan, equally known for total war, and for the saying: “The only good Indian is a dead Indian.” But we no longer tolerate Confederates. Among the reasons is that we claim to ease the pain of black people — a pain I feel looking at the Genghis Kahn monument. Another reason, we’re told, is that the statues are “dog-whistles” to racists and white supremacists — a particular danger now, evidenced in the election of Donald Trump. A danger, I think, that’s been largely trumped up as a way to keep politicians and newscasters politically relevant.

For these reasons, or politicians have removed every last confederate monument in Florida, the last being a large grave-stone in the Woodlawn cemetery. Virginia’s governor has similarly declared his intention to remove them all from his state. The city of Baltimore removed all four civil-war monuments in the middle of one busy night, August 18, 2017, and the University of Texas did similarly, working at night. New York City removed a plaque remembering Robert E. Lee for planting a tree at Ft. Hamilton, And, last week, an honorary window at the Washington cathedral where Lee had been a deacon.

Statues of Robert E. Lee are a particular target. There are quite a few in Virginia where his family was prominent — it was Richard H. Lee’s motion in the Continental Congress that carried as independence; his home now serves as Arlington Cemetery. While Lee opposed slavery and freed his slaves before the war, he fought for the Confederacy, so clearly he didn’t oppose slavery as totally as we would like. And Lee only freed his wife’s inherited slaves in 1862, fairly late, though Grant still had slaves at that time. Besides, in 1852, Lee caused an escaped slave to be whipped. I imagine he did the same to runaway soldiers. Historians used to praise Lee, but now call him a cruel racist. In hindsight, we imagine we would have done much better.

General Lee statue being removed from University of Texas.

General Lee statue being removed from the University of Texas.

As best I can tell, Virginians still remember Lee fondly, particularly soldiers, veterans, and those who imagine themselves leading men in difficult situations. When I try to put myself in Lee’s position, I find I can’t imagine myself doing better or achieving more. His life involved thousands of divisions and hundreds of inspiring actions. In the choice to fight for Virginia and not for the north, I note that Lee was given the same no-win choice as Genghis’s trapped Chinese: join the Union army and kill your brothers, or be killed by that army. The exchange appears in this movie. I admire Lee’s courage to stand by his brothers; it seems the more honorable of two bad choices. Early in his life, Lee committed himself to only honorable behavior  — according to his conception. This is all I expect from myself, and the most I hope for from any other person.

Another thing is Lee’s surrender. I find it a model of how to end a war so that lasting peace is achieved. It’s remembered in Johnny Cash’s song, “God Bless Robert E. Lee.”  Another song, “The night they drove old Dixie down” calls Lee “the very best.” I would be hard pressed to find a better US general: one who won more or was better loved.

Japanese resettlement.

Japanese resettlement in WWII. Our history is full of painful decisions by people we admire. Let’s try to not repeat our mistakes or pretend we don’t make them.

A killer complaint lodged against Lee, and against all the confederates, is that they were traitors. If so, George Washington and Ben Franklin were traitors too. In England, Benedict Arnold is honored as a patriot with a statue on Trafalgar square, but we do not honor him, rightly I think. He turned on his friends and brothers. I think it’s politics that’s motivated the current spate of removal. Most of the confederate statues stand (stood) in Democrat-leaning cities of five Republican-leaning states: Virginia, Texas, Georgia, North Carolina, and Mississippi. The white, non-college country-folk of these states are being pitted against the darker, college-educated city folk in a fight for their hearts and pocket books.

As for my guess at interpretation of the statues themselves. I’m inclined to suggest that the statues and their inscriptions do not appear racists to me, so much as soldierly. The statues were largely erected between the Spanish-American war and WWII with soldierly (to my eyes) comments. Baltimore monument to Jackson and Lee, reads on one side: “STRAIGHT AS THE NEEDLE TO THE POLE JACKSON ADVANCED TO THE EXECUTION/ OF MY PURPOSE” and on the other side: “SO GREAT IS MY CONFIDENCE IN GENERAL LEE THAT I AM WILLING TO FOLLOW HIM BLINDFOLDED.” Another Baltimore inscription: “THEY FOUGHT AS GENTLEMEN.” To me this latter is a swipe at Sherman and Sheridan, who did not. Removing these statues is a swipe at the honor of southern soldiers. The statues now read “BLACK LIVES MATTER,” a slogan I read as anti-police, anti-Trump, and anti-white.

The remnant of Baltimore's Lee- Jackson statue, showing the old inscription and the new.

The remnant of Baltimore’s Lee – Jackson statue with the old inscription and the new..To me, the old inscription is military, mostly, and not as racist as the new.

The pain of black America is real, but the thing that’s missed is that it is similar to the pain of rural white America. Both have been left behind. I’ve noted that urban black Americans and rural whites have virtually no savings, It could be the two poor cultures don’t realize they have much in common. Or it could be (I think) some folks purposefully fermenting dissension. What is needed, at least is better financial sense, and a recognition that race isn’t racism, but to listen to CNN or read the New York Times, such understandings seem unlikely. The Trump election shocked everyone, I think, those who voted for him and those who didn’t — and perhaps even Trump himself. Hillary, it seems had already bought a house in DC to house her staff. The surprise is not a reason to turn on one’s fellow. I can hope that Trump will prove to be a great president. For now, he is the president, and we are faced by nuclear enemies. It hardly helps to see half of our electorate call the other half racists and deplorables. As with a bundle of arrows, we have strength in union, weakness in disunion. May we all be blessed for a good, sweet year of peace and brotherly love

Robert E. Buxbaum. September 24, 2017. Perhaps my fondness for Lee is because I’m named after him. Here’s my theory for why Mongol arrows flew further.

Health vs health administration

Leave a reply

One of the great patterns of government is that it continually expands adding overseers over overseers to guarantee that those on the bottom do their work honestly. There are overseers who check that folks don’t overcharge, or take bribes, or under-pay. There are overseers to check shirking, and prevent the hiring of friends, to check that paperwork is done, and to come up with the paperwork, and lots of paperwork to assert that no one is wasting money or time in any way at all. There have been repeated calls for regulation reform, but little action. Reform would require agreement from the overseers, and courage from our politicians. Bureaucracy always wins.

The number of health administrators has risen dramatically; doctors, not so much.

By 2009 the number of health administrators was rising dramatically faster than the number of doctors; it’s currently about 20:1.

The call for reform is particularly strong in healthcare and the current, Obamacare rules are again under debate. As of 2009 we’d already reached the stage where there were fourteen healthcare administrators for every doctor (Harvard Business Review), and that was before Obamacare. By 2013, early in the Obamacare era, the healthcare workforce had increased by 75%, but 95 percent of those new hires were administrators: we added 19 administrators per doctor. Some of those administrators were in government oversight, some worked in hospitals filling out forms, some were in doctors offices, and some were in the government, writing the new rules and checking that the rules were followed. A lot of new employment with no new productivity. Even if these fellows were all honest and alert, there are so many of them, that there seems no way they do not absorb more resources than the old group of moderately supervised doctors would by laziness and cheating.

Overseers fill ever-larger buildings, hold ever-more meetings, and create ever-more rules and paperwork. For those paying out of pocket, the average price of healthcare has risen to $25,826 a year for a family of four. That’s nearly half of the typical family income. As a result people rarely buy healthcare insurance (Obamacare) until after they are too sick to work. Administering the system take so much doctor time that a Meritt Hawkins study finds a sharp decline in service. The hope is that Congress will move to reverse this — somehow.

With more administrators than workers, disagreements among management becomes the new normal.

With more administrators than workers, disagreements among management becomes the new normal. Doctors find themselves operating in “The Dilbert Zone”.

Both Democrats and Republicans have complained about Obamacare and campaigned to change or repeal it, but now that they are elected, most in congress seem content to do nothing and blame each other. If they can not come up with any other change, may I suggest a sharp decrease in the requirements for administrative oversight, with a return to colleague oversight, and a sharp decrease in the amount of computerized documentation. The suggestion of colleague oversight also appears here, Harvard Business Review. Colleague oversight with minimal paperwork works fine for plumbers, and electricians; lawyers and auto-mechanics. It should work fine for doctors too.

Robert Buxbaum, September 19, 2017. On a vaguely similar topic, I ask is ADHD is a real disease, or a disease of definition.

Estimating the strength of an atom bomb

1 Reply

As warfare is a foundation of engineering, I thought I’d use engineering to evaluate the death-dealing power of North Korea’s atomic/hydrogen bomb, tested September 3, 2017. The key data in evaluating a big bomb is its seismic output. They shake the earth like earthquakes do, and we measure the power like earthquakes, using seismometers. I’ve seen two seismographs comparing the recent bomb to the previous. One of these, below, is from CTBTO, the Center for Test Ban Treaty Oversight, via a seismometer in western Kazakhstan (see original data and report).

Seismic output of all North Korean nuclear tests.

Seismic output, to scale, of all declared DPNK nuclear tests as observed from IMS station AS-59 in Western Kazakhstan

North Korea’s previous bomb, exploded 9 September 2016, was reported to be slightly more powerful than the ones we dropped on Hiroshima and Nagasaki, suggesting it was about 20 kilotons. According to CTBTO, it registered 5.3 on the Richter scale. The two tests before that appear somewhat less powerful, perhaps 7-10 kilotons, and the two before that appear as dismal failures — fizzles, in atomic bomb parlance. The MOAB bomb, by comparison, was 9 Tons, or 0.009 kiloTons, a virtual non-entity.

To measure the output of the current bomb, I place a ruler on my screen and measure the maximum distance between the top to bottom wiggles. I find that this bomb’s wiggles measure 5 cm, while the previous measures 5 mm. This bomb’s wiggles are ten times bigger, and from this I determine that this explosion registered 6.3 on the Richter scale, 1.0 more than the previous — the Richter scale is the logarithmic measure of the wiggle amplitude, so ten times the shake magnitude  is an addition of 1.0 on the scale. My calculation of 6.3 exactly matches that of the US geological survey. The ratio of wiggle heights was less on the, NORSAR seismometer, Norway, see suggesting 5.8 to 5.9 on the Richter scale. The European agencies have taken to reporting 6.1, an average value, though they originally reported only the 5.8 from NORSAR, and a bomb power commensurate with that.

We calculate the bomb power from the Richter-scale measure, or the ratio of the wiggles. Bomb power is proportional to wiggle height to the 3/2 power. Using the data above, ten times the wiggle, this bomb appears to be 10^3/2 = 31.6 times as powerful as the last, or 31.6 x 20kTon = 630kTon (630,000 tons of TNT). If we used the European value of 6.1, the calculated power would be about half this, 315 kTons, and if we used the NORSAR’s original value, it would suggest the bomb had less than half this power. Each difference of 0.2 on the Richter scale is a factor of two in power. For no obvious reason we keep reporting 120 to 160 kTons.

NORSAR comparison of North Korean bomb blasts

NORSAR comparison of North Korean blasts — suggests the current bomb is smaller; still looks like hydrogen.

As it happens, death power is proportional to the kiloton power, other things being equal. The bombs we dropped on Hiroshima and Nagasaki were in the 15 to 20 kTon range and killed 90,000 each. Based on my best estimate of the bomb, 315 kTons, I estimate that it would kill 1.6 million people if used on an industrial city, like Seoul, Yokohama, or Los Angeles. In my opinion, this is about as big a bomb as any rational person has reason to make (Stalin made bigger, as did Eisenhower).

We now ask if this is an atom bomb or a hydrogen-fusion bomb. Though I don’t see any war-making difference, if it’s a hydrogen bomb that would make our recent treaty with Iran look bad, as it gave Iran nuclear fusion technology — I opposed the treaty based on that. Sorry to say, from the seismic signature it looks very much like a hydrogen bomb. The only other way to get to this sort of high-power explosion is via a double-acting fission bomb where small atom bomb sets off a second, bigger fission bomb. When looking at movies of Eisenhower-era double-acting explosions, you’ll notice that the second, bigger explosion follows the first by a second or so. I see no evidence of this secondary-delay in the seismic signature of this explosion, suggesting this was a hydrogen bomb, not a double. I expect Iran to follow the same path in 3-4 years.

As a political thought, it seems to me that the obvious way to stop North Korea would be to put pressure on China by making a military pact with Russia. Until that is done, China has little to fear from a North Korean attack to the south. Of course, to do that we’d likely have to cut our support of NATO, something that the Germans fear. This is a balance-of-power solution, the sort that works, short of total annihilation. It was achieved at the congress of Vienna, at the treaty of Ghent, and by Henry Kissinger through détente. It would work again. Without it, I see the Korean conflict turning hot again, soon.

Robert Buxbaum, September 11, 2017.

Japanese zen art – just go away

Leave a reply
Japanese zen spiral -- it's a cartoon about meditation. It looks like a monk and a spiral, and note that both ends point inward.

Japanese zen spiral — it’s a cartoon about meditation. It looks like a monk and a spiral, and note that both ends point inward. Cute.

The purpose of art is not generally to show the world as it is, but to show a new, better way to look at the world. As such, my take on Japanese zen art, is that it is a very cool, fun way to say “just go away.” What follows are some nice (to my eyes) examples, with my commentary.

As with most Japanese art, the zen art looks simpler and more free-form than western religious art. In a sense that is true: there are far fewer lines, but the paintings take as long to make, to a good estimate, since they only appear to have been made with casual ease: flicks of the wrist and waves of the hand. In actuality the artist had a vision of what he wanted, and then made free-hand waving copy after copy until he had some correct, free-looking ones ready for delivery. Because of this, you can look for a meaning in every wiggle — something that you would not do with US free-form abstracts, or with religious paintings of the 1600s. Take daVinci’s last supper — the grand layout is clearly planned and meaningful, the details of the wrinkles, not really. With these, though, no detail is accidental, and the non-accidental sense, as I see it, is “just go away.”

Buddhist Master. I can imagine this work is effective at keeping guests from over-staying their welcome.

Buddhist Master. Art like this keeps away guests.

Take the spiral at left. It’s sort of cool, and claims to be an allusion to meditation. Mystic, no? As I look carefully a the spiral, the first remarkable thing I see is that it circles in on itself at both ends. At a simple level, I think that’s an allusion to the inward nature of meditation, but note that, at the top end of the coil there’s a wiggle that looks like a face. I take that to be a monk’s face, looking away. The geometry of the coil then suggests the legs and thighs of the rest of the monk (sitting?). If that’s the image (and I think it is) the fact that the monk is facing away from you, leaving you behind suggests to me that the owner has no desire to have you join him. I see nothing in this that would cause another person to want to meditate either. There is nothing attractively persuasive as in western religious art. Here’s an essay I wrote on meditation.

Perhaps it’s just me, but I also imagine these artists living on an industrial treadmill, making painting after painting in his shop and throwing most away because, for example, the monk’s back extended past the paper. Western expressionism also sometimes puts many paintings on a single canvas, but the hidden image stays, at least in a sort-of half shadow. And the wiggles strive to be less learned, even if the faces of some western religious art is distant –even more distant often. At right, above, you’ll find another popular zen-art approach. It shows a zen master in nearly full face. As with most zen art, the master (Buddha or a disciple) looks calm -ish with a sense of the put-upon, as if he were Christ carrying the cross of you being there. Perhaps the intent was to make you go off and meditate, or to see society as worthless, but I think the more-likely message in the master’s look is “why me Lord.” The master looks like he isn’t unhappy with life, just unhappy with you being there. I imagine that this work was placed in a noble’s living room or study for the same reason that many American today put up a picture of Yosemite Sam, sometimes (for those who don’t get art) “Keep Out! This means you.”

A monkey looks at the moon in a well. Don't touch, the moon seems to say.

A monkey looks at the moon in a well. Don’t touch, the moon seems to say.

As with the Warner-bros. classic, there is a flowing look to the brushwork, but a fair amount of detail. As with the Warner Bros. cartoon, the casual lines seem to serve the purpose of keeping the viewer from taking offense at the message. Sort of like, “Don’t go away mad, just go away.” Cool, but I also like Western cartooning.

As one last example, at left you’ll see a painting illustrating a zen parable. in this case it’s the parable of the monkey’s and the image of the moon. Shown is the moon’s reflection in the water of a well — moon is that big round face. A monkey is about to touch the moon-image, and as we can expect, when the monkey touches the image, it disappears. There are several understandings to be gained from this, e.g. that all is illusion (similar to Plato and his cave), or suggesting that it is better to look at life than to interact with it. Which is the main meaning? In this picture, my sense is that the moon seems put-upon, and afraid. Thus, the lesson I take from the picture is one of inaction: “don’t touch the reflection.” Once again, the choice to depict a frightened moon rather than an impassive one, seems to be the painter’s way of saying “please go away.” Very cool image, but as messages go, that’s the one I see in most Japanese zen art.

Robert Buxbaum, August 17, 2017. I’ve also written on surreal art (I like it a lot, and find it ‘funny’) and on Dada, and conceptual (I like it too, playfully meaningful, IMHO). If you like zen jokes (and who doesn’t) here’s a story of the Buddhist and the hot-dog vendor, and how many zen Buddhists does it take to change a lightbulb? Four. See why.

Kennedy’s perfect, boring college-entry essays

2 Replies

To get into any college you have to write an essay or two, generally including one describing why you want to go that particular college, and many students have trouble. How do I make myself stand out, they ask. My suggestion: Don’t. Make it clear that you want to go, but dare to be dull with the details. John Kennedy did; you can too.

JFK's dull letter to Harvard. It's his only essay.

JFK’s dull letter to Harvard. It’s his only essay.

Most school essays limit the number of words. The reviewer too prefers you keep it short. If you want to go to Harvard, or Princeton, or Iowa state, show you can say what needs to be said within the word limit. The first sentence must tell them that you want to go that college, specifically. Mention the college: you want to go to Old Ivy, say. Once that’s taken care of, just state your reasons. Unless you’re going into the writing program, the baldest, simplest terms will work just fine — e.g. that Old Ivy provides an excellent education. It’s better if you can mention a more-specific field of study, e.g. liberal arts or zoölogy, but that’s not necessary. You can now list three or so details to back up your claims. For example, you might mention that the zoölogy program at Old Ivy is well-regarded (mention the school often), that you enjoy their sports team (the ground-hogs, say), or their extracurriculars. Mention that your dad went there or your uncle (and is your hero — hero is a good word) or that you like the location. Surely there is some reason you want to go. If you can mention a famous teacher or alumnus, all the better. Flesh it out if you have space; don’t if you don’t. Conclude with a sentence pointing to the future: that this school will help me do something you want to achieve. You can be specific or not, but don’t lie. Dull is more effective than a lie. I’ve copied, above, John Kennedy’s essay to Harvard, and below his essay to Princeton. These essays follow the pattern, and are dull within the pattern. His conclusion for the first essay: that he wants to go to Harvard to be “a Harvard Man.” He got in. He used the same, dull letter for Princeton, but had more space. For Princeton he said It would have a good effect on me, and that he wanted to be “a Princeton Man.” He got into Princeton too, and went there for two months before switching to Harvard.

John F. Kennedy's, almost identical letter to Princeton. He got in there too.

John F. Kennedy’s, almost identical letter to Princeton. He got in there too.

You may think that letters like this only work if you are John F. Kennedy, and to some extent that is true. But not totally. I got into Princeton grad school from a background in public school, with no famous relatives or money. My grades were better than JFKs, but my essay had the same structure with some more specifics. As I recall, I explained that I wanted to go to Princeton because I wanted to study chemical engineering in a top department. I may have mentioned a famous professor, and stated I wanted to work on nuclear fusion — a big Princeton specialty at the time. That’s about all, as I recall.

This formula can be tweaked for the other college (and non-college) essays. I’ve previously written about the two speeches at the opening of the Gettysburg cemetery, in 1863. Edwin Everett gave the first speech of the day, excerpted and analyzed here. His speech followed the formula and was lauded. He told folks that it was important that we are here honoring the dead, and followed with three or four reasons for why it was important. His conclusion pointed to the future significance of the events. Republicans and Democrat listeners agreed this was a speech to remember from a scholar of note. Everett’s face graced the $50 bill for the 40 years after his death.

Abraham Lincoln also spoke at the Gettysburg dedication, but he didn’t follow the formula. He spoke of liberty, and America, and of a government of the people. His speech was panned at the time, even by Republicans. More details here. Though people now see his Gettysburg address as a landmark, at the time even the Republican press didn’t like it  Fortunately for Lincoln and the republic, they warmed to the speech over the next year – in time for the election of 1864. When you apply to college, you want entry now. You can’t wait a year for people to warm to your essay. Stick to the formula. You don’t want the compliment of finding, years from now, that one of the reviewers who rejected you remembers your words fondly. That will be too late. Write for the dull audience in front of you; help them put your application in the “accepted” box. As a last note: If you can not find any truthful reason that you want to go to Harvard or Old Ivy you probably should not be going there. The beginning of wisdom is self-knowledge, and the primary audience for your essay is you.

If you find you have good reasons, but find you need help with the process or with your english grammar, I should mention that my niece owns a company to help folks get into college — link here. She also has a book “From Public School to The Ivy League.”

Robert E. Buxbaum, August 7, 2017. Some two years ago, I wrote an essay for my daughter on the joys and pressures of entering her junior year in high school. Here it is. 

Activated sludge sewage treatment bioreactors

1 Reply

I ran for water commissioner of Oakland county in 2016, a county with 1.3 million people and eight sewage treatment plants. One of these plants uses the rotating disk contractor, described previously, but the others process sewage by bubbling air through it in a large tank — the so-called, activated sludge process. A description is found here in Wikipedia, but with no math, and thus, far less satisfying than it could be. I thought I might describe this process relevant mathematics, for my understanding and those interested: what happens to your stuff after you flush the toilet or turn on the garbage disposal.

Simplified sewage plant: a plug-flow reactor with a 90+% solids recycle used to maintain a high concentration of bio-catalyst material.

Simplified sewage plant: a bubbling, plug-flow bio-reactor with 90% solids recycle and a settler used to extract floc solids and bio-catalyst material.

In most of the USA, sanitary sewage, the stuff from your toilet, sink, etc. flows separately from storm water to a treatment plant. At the plant, the sewage is first screened (rough filtered) and given a quick settle to remove grit etc. then sent to a bubbling flow, plug-flow bioreactor like the one shown at right. Not all cities use this type of sludge processes, but virtually every plant I’ve seen does, and I’ve come to believe this is the main technology in use today.

The sewage flows by gravity, typically, a choice that provides reliability and saves on operating costs, but necessitates that the sewage plant is located at the lowest point in the town, typically on a river. The liquid effluent of the sewage, after bio-treatment is typically dumped in the river, a flow that is so great more than, during dry season, more than half the flow of several rivers is this liquid effluent of our plants – an interesting factoid. For pollution reasons, it is mandated that the liquid effluent leaves the plant with less than 2 ppm organics; that is, it leaves the plant purer than normal river water. After settling and screening, the incoming flow to the bio-reactor typically contains about 400 ppm of biomaterial (0.04%), half of it soluble, and half as suspended colloidal stuff (turd bits, vegetable matter, toilet paper, etc). Between the activated sludge bio-reactor and the settler following it manage to reduce this concentration to 2 ppm or less. Soluble organics, about 200 ppm, are removed by this cellular oxidation (metabolism), while the colloidal material, the other 200 ppm, is removed by adsorption on the sticky flocular material in the tank (the plug-flow tank is called an oxidation ditch, BTW). The sticky floc is a product of the cells. The rate of oxidation and of absorption processes are proportional to floc concentration, F and to organic concentration, C. Mathematically we can say that

dC/dt = -kFC

where C and F are the concentration of organic material and floc respectively; t is time, and k is a reaction constant. It’s not totally a constant, since it is proportional to oxygen concentration and somewhat temperature dependent, but I’ll consider it constant for now.

As shown in the figure above, the process relies on a high recycle of floc (solids) to increase the concentration of cells, and speed the process. Because of this high recycle, we can consider the floc concentration F to be a constant, independent of position along the reactor length.

The volume of the reactor-ditch, V, is fixed -it’s a concrete ditch — but the flow rate into the ditch, Q, is not fixed. Q is high in the morning when folks take showers, and low at night. It’s also higher — typically about twice as high — during rain storms, the result of leakage and illegal connections. For any flow rate, Q, there is a residence time for a bit of sewage flowing through a tank, τ = V/Q. We can now solve the above equation for the value of τ for an incoming concentration C° = 400 ppm, an outgoing concentration Co of 2 ppm. We integrate the equation above and find that:

ln (C°/Co) = kFτ

Where τ equals the residence time, τ = V/Q. Thus,

ln (C°/Co) = kFV/Q.

The required volume of reactor, V, is related to the flow rate, Q, as follows for typical feed and exit concentrations:

V = Q/kF ln( 400/2) = 5.3 Q/kF.

The volume is seen to be dependent on F. In Oakland county, tank volume V is chosen to be one or two times the maximum expected value of Q. To keep the output organic content to less than 2 ppm, F is maintained so that kF≥ 5.3 per day. Thus, in Oakland county, a 2 million gallon per day sewage plant is built with a 2-4 million gallon oxidation ditch. The extra space allows for growth of the populations and for heavy rains, and insures that most of the time, the effluent contains less than 2 ppm organics.

Bob Martin by the South Lyon, MI, Activated Sludge reactor

Bob Martin chief engineer the South Lyon, MI, Activated Sludge plant, 2016. His innovation was to control the air bubblers according to measurements of the oxygen content. The O2 sensor is at bottom; the controller is at right. When I was there, some bubblers were acting up.

As you may guess, the activated sludge process requires a lot of operator control, far more than the rotating disk contractor we described. There is a need for constant monitoring and tweaking. The operator deals with some of the variations in Q by adjusting the recycle amount, with other problems by adjusting the air flow, or through the use of retention tanks upstream or downstream of the reactor, or by adding components — sticky polymer, FeCl3, etc. Finally, in have rains, the settler-bottom fraction itself is adjusted (increased). Because of all the complexity. sewer treatment engineer is a high-pay, in demand, skilled trade. If you are interested, contact me or the county. You’ll do yourself and the county a service.

I’d mentioned that the effluent water goes to the rivers in Oakland county. In some counties it goes to the fields, a good idea, I think. As for the solids, in Oakland county, the solid floc is concentrated to a goo containing about 5% solids. (The goo is called unconsolidated sludge) It is shipped free to farmer fields, or sometimes concentrated to more than 5% (consolidated sludge), and provided with additional treatment, anaerobic digestion to improve the quality and extract some energy. If you’d like to start a company to do more with our solids, that would be very welcome. In Detroit the solids are burned, a very wasteful, energy-consuming process, IMHO. In Wisconsin, the consolidated sludge is dried, pelletized, and sold as a popular fertilizer, Milorganite.

Dr. Robert Buxbaum, August 1, 2017. A colleague of mine owned (owns?) a company that consulted on sewage-treatment and manufactured a popular belt-filter. The name of his company: Consolidated Sludge. Here are some sewer jokes and my campaign song.

Global warming’s 19 year pause

2 Replies
Global temperatures measured from the antarctic ice showing stable, cyclic chaos and self-similarity.

Global temperatures measured from the antarctic ice shows stable chaos and self-similarity.

The global climate is, as best I can tell, chaotic with 100,000 year ice-age cycles punctuated by smaller cycles of 1000 years, 100 years, etc. On the ice-age time scale shown at left, the temperature rise of the last century looks insignificant and very welcome; warm seems better than cold in my eyes. But the press and academic community has focused on the evils of warmth — global warming. They point out that temperatures have risen 1 1/2 °C since the little ice age of the early 1600s, and that 1/2 °C of this has occurred since 1900. Al Gore won a Nobel prize for his assertion that the rate of rise had accelerated to 4°C per century — a “hockey-stick change” caused by industrial CO2. This change was expected to bring disaster by 2015: The arctic was supposed to be ice-free, and Manhattan was expected to sink. I’ve posted a “Good Morning America” clip from 2008 highlighting this “inconvenient truth”.

Our 19 1/2 year global warming pause; plot from Andrew Watts with Al Gore's prediction shown in red. During the time shown, the atmospheric CO2 content has gone up by about 25%, but the prediction has not come to pass.

Our 19 1/2 year global warming pause; plot from Andrew Watts with Al Gore’s prediction shown in red. So far, the prediction has not come to pass.

As it happens, not only hasn’t global warming accelerated, it seems to have paused. There have been no significant temperature changes since late 1997, as shown.  The main explanations are clouds and solar variation: variations that the Obama administration claims will end any day now. The problem, as I see it, is that climate is fundamentally chaotic, and thus unpredictable except on the very long, ice-age, timescale. It will thus always make fools of those who predict.

This is not to say that pollution is good, or that CO2 is, but it suggests our models and remedies are flawed. The CO2 content of the air has increased 25% over the past 19 years. It now mostly comes from China and India, countries that enthusiastically endorse having us reduce our output. My thinking is that lowering US production will, in no way, protect us from the dire predictions below.

Despite pressure from China and India, the US pulled out of the Paris climate accord last month. It now seems several other countries will pull out as well.

Robert Buxbaum, July 27, 2017. I’ve also written about how the global warming of the mid 1800s lead us to have the president’s Resolute desk.

Detroit 1967 to 2017: unemployment comes down, murder rate doesn’t.

Leave a reply

Almost 50 years ago today, July 23, 1967 white policemen raided an unlicensed, “blind pig” bar in a black neighborhood, the 12th street of Detroit, and the city responded with four days of rioting, 43 killings (33 black, 10 white), 2509 stores looted, and over 1000 fires. In 2017, at last the city is beginning to show signs of recovery. By 2015 the city’s unemployment had gone down from about 20% to 12%, and  in the first six months 2017, the firs six months of the Trump presidency, 2017 it’s gone down again to 7 1/2%. It’s not that 7 1/2% unemployment is good, but it’s better. Per-hour salaries are hardly up, but I take that as better than having a high average salary at very low employment. As a point of reference, the unemployment rate in Detroit in 1967, before the riots was 3.4%. Within weeks, 150,000 jobs were lost, and anyone who could leave the city, did.

Detroit Unemployment rates are way down, but the city still looks like a mess.

Detroit Unemployment rates are way down, but the city still looks like a mess.

Another issue for Detroit is its uncommonly high murder rate. In the mid-80s, Detroit had the highest murder rate in the US, about 55 murders per 100,000 population per year (0.055%/year). As of February 1, 2017, the murder rate was virtually unchanged: 50 per 100,000 or 0.05%/year, but two cities have higher rates yet. At present rates, you have a 3.5% of dying by homicide if you live in Detroit for 70 years — even higher if you’re male. The rate in the rest of the US is about 1/10th this, 0.005%/year, or 5 per 100,000, with a dramatic difference between rural and urban populations.

Murder rate in 50 cities with Detroit highlighted. From The Economist, February 2017.

Murder rate in 50 cities with Detroit highlighted, from The Economist.

One of the causes of the high murder rate in Detroit, and in the US generally, I suspect, is our stiff, minimum-penalties for crime. As sir Thomas Moose pointed out, when crime is punished severely, there is a tendency to murder. If you’re going to spend the next 20 years behind bars, you might as well try any means you can to escape. Another thought — the one favored by social liberals — is that it’s the presence of guns in the US encourages murder. It may, but it also seems to prevent crime by allowing the victim to defend himself or herself. And the effect on murder is not so clear, if you consider suicide as a form of murder. In countries like Canada with few guns, people kill themselves by hanging or by throwing themselves off high buildings. My hope is that Detroit’s murder rate will drop in 2017 to match its improved economic condition, but have no clear reason to think it will.

Robert Buxbaum, July 20, 2017. Here are some suggestions I’ve made over the years.

A rotating disk bio-reactor for sewage treatment

2 Replies

One of the most effective designs for sewage treatment is the rotating disk bio-reactor, shown below. It is typically used in small-throughput sewage plants, but it performs quite well in larger plants too. I’d like to present an analysis of the reactor, and an explanation of why it works so well.

A rotating disc sewage reactor.

A rotating disk sewage reactor; ∂ is the thickness of the biofilm. It’s related to W the rotation rate in radians per sec, and to D the limiting diffusivity.

As shown, the reactor is fairly simple-looking, nothing more than a train of troughs filled with sewage-water, typically 3-6 feet deep, with a stack of discs rotating within. The discs are typically 7 to 14 feet in diameter (2-4 meters) and 1 cm apart. The shaft is typically close to the water level, but slightly above, and the rotation speed is adjustable. The device works because appropriate bio-organisms attach themselves to the disk, and the rotation insures that they are fully (or reasonably) oxygenated.

How do we know the cells on the disc will be oxygenated? The key is the solubility of oxygen in water, and the fact that these discs are only used on the low biological oxygen demand part of the sewage treatment process, only where the sewage contains 40 ppm of soluble organics or less. The main reaction on the rotating disc is bio oxidation of soluble carbohydrate (sugar) in a layer of wet slime attached to the disc.

H-O-C-H + O2 –> CO2 + H2O.

As it happens, the solubility of pure oxygen in water is about 40 ppm at 1 atm. As air contains 21% oxygen, we expect an 8 ppm concentration of oxygen on the slime surface: 21% of 40 ppm = 8 ppm. Given the reaction above and the fact that oxygen will diffuse five times more readily than sugar at least, we expect that one disc rotation will easily provide enough oxygen to remove 40 ppm sugar in the slime at every speed of rotation so long as the wheel is in the air at least half of the time, as shown above.

Let’s now pick a rotation speed of 1/3 rpm (3 minutes per rotation) and see where that gets us in terms of speed of organic removal. Since the disc is always in an area of low organic concentration, it becomes covered mostly with “rotifers”, a fungus that does well in low nutrient (low BOD) sewage. Let’s now assume that mass transfer (diffusion) of sugar in the rotifer slime determines the thickness of the rotifera layer, and thus the rate of organic removal. We can calculate the diffusion depth of sugar, ∂ via the following equation, derived in my PhD thesis.

∂ = √πDt

Here, D is the diffusivity (cm2/s) for sugar in the rotifera slime attached to the disk, π = 3.1415.. and t is the contact time, 90 seconds in the above assumption. My expectation is that D in the rotifer slime will be similar to the diffusivity sugar in water, about 3 x 10-6 cm2/s. Based on the above, we find the rotifer thickness will be ∂ = √.00085 cm2 = .03 cm, and the oxygen depth will be about 2.5 times that, 0.07 cm. If the discs are 1 cm apart, we find that, about 14% of the fluid volume of the reactor will be filled with slime, with 2/5 of this rotifer-filled. This is as much as 1000 times more rotifers than you would get in an ordinary constantly stirred tank reactor, a CSTR to use a common acronym. We might now imagine that the volume of this sewage-treatment reactor can be as small as 1000 gallons, 1/1000 the size of a CSTR. Unfortunately it is not so; we’ll have to consider another limiting effect, diffusion of nutrients.

Consider the diffusive mass transfer of sugar from a 1,000,000 gal/day flow (43 liters/sec). Assume that at some point in the extraction you have a concentration C(g/cc) of sugar in the liquid where C is between 40 ppm and 1 ppm. Let’s pick a volume of the reactor that is 1/20 the normal size for this flow (not 1/1000 the size, you’ll see why). That is to say a trough whose volume is 50,000 gallons (200,000 liters, 200 m3). If the discs are 1 cm apart, this trough (or section of a trough) will have about  4×10^8 cm2 of submerged surface, and about 9×10^8 total surface including wetted disc in the air. The mass of organic that enters this section of trough is 44,000 C g/second, but this mass of sugar can only reach the rotifers by diffusion through a water-like diffusion layer of about .06 cm thickness, twice the thickness calculated above. The thickness is twice that calculated above because it includes the supernatant liquid beyond the slime layer. We now calculate the rate of mass diffusing into the disc: AxDxc/z = 8×10^8 x 3×10-6 x C/.06 cm = 40,000 C g/sec, and find that, for this tank size and rotation speed, the transfer rate of organic to the discs is 2/3 as much as needed to absorb the incoming sugar. This is to say that a 50,000 gallon section is too small to reduce the concentration to ln (1) at this speed of disc rotation.

Based on the above calculation, I’m inclined to increase the speed of rotation to .75 rpm. At this speed, the rotifer-slime layer will be 2/3 as thin 0.2 mm, and we expect an equally thinner diffusion barrier in the supernatant. At this faster speed, there is now 3/2 as much diffusion transfer per area because the thinner diffusion barrier, and we can expect a 50,000 liter reactor section to reduce the initial concentration by a fraction of 1/2.718 or C/e. Note that the mass transfer rate to the discs is always proportional to C. If we find that 50,000 gallons of tank reduces the concentration to 1/e, we find that we need 150,000 gallons of reactor to reduce the concentration of sugar from 40 ppm to 2 ppm, the legal target, ln (40/2) = 3. This 150,000 gallons is a remarkably small volume to reduce the sBOD concentration from 40 ppm to 2 ppm (sBOD = soluble biological oxygen demand), and the energy use is small too if the disc bearings are good.

The Holly sewage treatment plant is the only one in Oakland county, MI using the rotating disc contacted technology. It has a flow of 1,000,000 gallons per day, and has a contactor trough that is 215,000 gallons, about what we’d expect though their speed is somewhat higher, over 1 rpm and their input concentration is likely lower than 40 ppm. For the first stage of sewage treatment, the Holly plant use a vertical-draft, trickle-bed reactor. That is they drizzle the sewage-liquids over a slime-coated packing to reduce the sBOD concentration from 200 ppm to before feeding the flow to the rotating discs. My sense of the reason they don’t do the entire extraction with a trickle bed is that the discs use far less energy.

I should also add that the back-part of the disc isn’t totally useless oxygen storage, as it seems from my analysis. Some non-sugar reactions take place in the relatively anoxic environment there and in the liquid at the bottom of the trough. In these regions, iron reacts with phosphate, and nitrate removal takes place. These are other important requirements of sewage treatment.

Robert E. Buxbaum, July 18, 2017. As an exercise, find the volume necessary for a plug flow reactor or a stirred tank reactor (CSTR) to reduce the concentration of sugar from 40 ppm to 2 ppm. Assume 1,000,000 gal per day, an excess of oxygen in these reactors, and a first order reaction with a rate constant of dC/dt = -(0.4/hr)C. At some point in the future I plan to analyze these options, and the trickle bed reactor, too.

Peace killed the Indian, ended Spain’s golden age

Leave a reply

The why of history is always more speculative than the what. Yet, to write about only the what, is to do only half of the job, if that. The what is largely interchangeable: the names of kings and generals, the dates and locals of battles and treaties. It’s the why that adds interest, and provides whatever lessons one can take forward. With this as background, I’d like to speculate on the cause of: the destruction of the American Indian, and the end of the golden age of Spain. For both and some others, I suggest an unusual villain, peace: too much peace. It’s a speculative why, but bear with me.

Lets start with the American Indian. In the mid 1700s, Indians controlled the majority of the continent. They had an advanced society of six main nations, held together by mutual treaty. The Indians had few guns, but were not less intelligent than the Japanese or Chinese, suggesting that they could have learned to make them if they desired (or realized they needed to desire). The Japanese did so in short order. Indians addressed the Continental assemblies, and though they were not integrated, quite, they were not segregated either. But this first period of co-existence ended, as best i can tell, in the years of and following the French and Indian war. In the war, some Indians supported the French and some the British, and each side looked after their Indians. After peace was established, however, English leaders like Lord Jeffery Amherst set up to wipe out the Indians of both sides, “this execrable race,” with blankets infected with smallpox, and good old-fashioned cruelty. His activities are memorialized, on the cafeteria china used at Amherst Colleges till the 1960s.

Cup from the cafeteria of Amherst College shows Lord Jeff pursuing the Indians.

Cup from the cafeteria of Amherst College, used till the 1960s, shows Lord Jeffery Amherst pursuing a band of Indians. Purple and white are the Amherst colors. 

My thought of why he did it, and why he succeeded, is that the Indians had outlived their usefulness. The ones on the French side had been enemies, and might be again. The ones on his, English side were annoying and might turn in the next conflict. Besides, Lord Jeffery and his ilk had idle military power. Removing the Indians was something they could do. The army at peace could otherwise get destructive, or turn on him (I’m speculating here on motives).

This pattern appeared again in the Revolutionary war and in the War of 1812. During each war, Indians were befriended by both sides, and recruited. Indians fought important battles in each war, now mostly forgotten; the defense of Canada was largely by Indians. After each war, these Indians were largely betrayed. In the War of 1812, the Shawnee, Potawatomi, Ojibwa, and Creek mostly sided with the British, led by the fierce Shawnee general, Tecumseh. The Muscogee, Creek, Seminole, Choctaw, Cherokee, and Chickasaw, mostly sided with the US. Iroquois fought on both sides. In the years following the wars, these and these were sent west of the Mississippi. Those who had been allies with the US were paid for their land, those that sided with the British were not. A good price, but it was a forced sale none-the-less. I will speculate that they were exiled because they retained a government structure independent of the US, making them a threat. Also (I speculate) the military, Generals Harrison, Jackson, etc., had nothing better to do with an army that might have mutinied otherwise. By 1846, there was no serious future for the American Indian east of the Mississippi, and besides, there was an external enemy to fight — The Mexicans. My speculation: the Indians were destroyed by “the era of good feelings” that follows war.

In the case of Spain, I note that the Inquisition and Jewish expulsion followed suddenly after 300 years of science, art, literature, and coöperation. I also note that the Alhambra decrees (March 1492) followed almost immediately after the defeat the last major Moslem-held citadel, Granada in December, 1491, and the peace treaty of Granada (January 2, 1492). The Alhambra decrees of March 31, 1492 mandated that all Jews must convert or leave Spain, and gave free-reign to the Inquisition to punish heresy. At the time, the financier of the Spanish crown was a Jew, Don Isaac Abarbanel. And some years earlier another Jew, Shmuel HaNagged hand been vizier (2nd) to the king. My theory of the cause for the sudden switch is that it was not a sudden surge in religion, as some have suggested, but rather that the king and queen no longer needed an army or Jewish or Moslem allies, but they still had an army that might turn against them if not otherwise occupied.

In the interwar, peace years, Stalin removed 3 of the 5 top generals, 13 of 15 below them; 8 of 9 admirals, 50 of 57 army corps commanders, 154 out of 186 division commanders, 16 of 16 army commissars, and 25 of 28 army corps commissars.

In the interwar, peace years, Stalin removed 3 of the 5 top generals, 13 of 15 below them; 8 of 9 admirals, 50 of 57 army corps commanders, 154 out of 186 division commanders, 16 of 16 army commissars, and 25 of 28 army corps commissars. Peace is hell.

I’m reminded that peace is the background to intrigue in at least six of Shakespeare’s historical plays: Macbeth, Hamlet, Richard III, Lear, Julius Caesar, and Othello. Richard III explains his behavior as follows (Act I, Scene 1):  “Why, I, in this weak piping time of peace, have no delight to pass away the time, unless to spy my shadow in the sun and descant on mine own deformity.”

A few other examples: After WWI, most of Europe removed their bearded aristocracy, and Stalin used the peacetime to remove much of the communist leadership including many of his generals and former friends – this was especially so after signing a peace treaty with Germany. And, in the US after WWII, we entered a period of communist witch hunts — a mini Inquisition directed at the writers and artists who provided Allied propaganda during the war. Even a general good, like peace can leave casualties.

Robert Buxbaum, July 7, 2017. I like to speculate on the why of history, and like to imagine my speculations are partially true, at least.