Cement- a major source of carbon dioxide emissions and water usage- redefined

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Many of you know that MIT is one of my almae matres. I chose it both due to a personal reason (my ex-wife was accepted to BU) and because it was the antithesis of my undergraduate haunts. Brooklyn Poly basically taught one how to make things work (and minimized the theory). MIT was “gung-ho” on the theoretical aspects and less interested in real-life situations. I melded both of those attitudes into a balanced approach to engineering/business issues. Well, I just attended an MIT event that – at least for these disciplines- demonstrated that MIT is now interested in both.
MIT Professor Franz Ulm described his work with concrete. This is the most widely used man-made material in the world. Cement is among the oldest engineered construction materials, dating back to the Roman Empire (remember seeing all those extant aqueducts?). It basically starts out as limestone and clay mixtures that are then crushed into powder, and then subsequently heated to a very high temperature (1500 C) in kilns. This forces transformation of the materials, with tremendous potential energy bound into the powder. Upon mixing with water, the energy employed to bond the units into calcium-silicate-hydrate (C-S-H) complexes. . (Cement is NOT a molecule; while one could consider the composition to be (CaO)1.65(SiOs)(H2O)1.75, this is an approximation. ) At the microscopic level, these CSH units serve as a binder for the added sand and gravel ; this mixture is the concrete. Most of the carbon dioxide emissions in this manufacturing process result from heating the kiln to a temperature high enough to transfer energy into the powder. (Limestone is CaCO3; the heating removes the CO2 and the calcium oxide (CaO) is the active unit in the precursor)
There are some 25000 million tons of cement produced annually; all metals only account for 1350 million tons. More importantly in light of our desire to lessen our carbon footprint, this represents 32.5 billion GJ (gigaJoules) of energy, compared to 26.5 for metals. (And, notice how much MORE energy is required for the production of those metals.) This is equivalent to the power produced by some 700 nuclear power plants. There is one (1) cubic yard of concrete for each person on earth and 5% (some say 10%) of the earth’s CO2 emissions results from concrete manufacture.
Another way of looking at this is that 8 tons of concrete or 1 ton of cement is equivalent to 1 ton of carbon dioxide. If we could cut the carbon dioxide use by altering our cement technology, we could go a long way to solving our carbon crisis. This is even more critical when one recognizes that we are currently using some 3200 million tons of timber, while the earth is creating 2500 million tons a year.
If we converted all our heating to clean energy and sequestered carbon dioxide (solar, wind, etc.), our carbon dioxide emissions in 2050 will be on par with those of 2005- not much change. If we improved our concrete production technology, we would REDUCE our impact by 83% compared to 2005. It was estimated that if Europe (or America) would impose a carbon tax of $ 40/ton, it would wipe out concrete production in those areas, since it would be cheaper to import the concrete from Egypt.
By improving the strength of our concrete, we could reduce the size of our concrete beams and columns. There is an inverse relationship between size and strength for columns and perfect shells; the relationship for beams is X to the -2/3 power [ed:  NO superscripts seem to work here] . If we double the strength, we halve our carbon dioxide usage.
The process that he discussed involves ordering the atoms. (Remember, cement is NOT a molecule- see above) ; while one could consider the composition to be (CaO)1.65(SiOs)(H2O)1.75, this is an approximation. ) Normal concrete has a random structure; if we order it to make it more closely compacted (from 64% of volume to 74%), the strength is radically improved. [Although this was not discussed, these numbers closely match how crystals exist in nature. The most common structure is body centered cubic, which has a packing factor of about 68%; face centered is 74% packed.]
Even with all of these factors, the best approach is not for universal changes in concrete production, since there is a higher need for quality control and more skilled workers. The best approach for this use is in precast concrete used for bridges and special buildings. One example he cited was the Jakway Park Bridge In Iowa. This bridge used precast concrete 7.5 cm thick- instead of the normal 20 cm or so thick beams.
In addition to ordering the atoms to be more closely packed, the discussion included the incorporation of fibers and nanoparticles of titanium dioxide. The former usage increases the durability dramatically; the latter provide an added environmental benefit. When you incorporate the TiO2 nanoparticles, the ultraviolet irradiation in sunlight activates the oxygen atoms at the surface to break down NOx molecules; reducing air pollution. (This technology is in use at the Jubilee Church, formally known as Dio Padre Misericordioso. In addition to the air pollution benefit, the TiO2 keeps the concrete white (aesthetically pleasing; titanium dioxide is how we get “white” paper) and the concrete maintains the temperatures more evenly.)
What was NOT discussed was the water needs for this new concrete. When I inquired, Dr. Ulm pronounced that this would reduce the water usage concomitantly. It should be noted that concrete is one of the largest consumers of water in industry; it is why most concrete facilities are near water sources and why water reuse projects have focused on just that industry segment, as well.

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Congress (and the IRS) is going after S Corporations and their owners

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Today, I am going to talk about taxes- but for the small business owner. Like it or not, taxes are going to go up- not for everyone, but small business is a ripe target. Part of the reason is that small business- just like big business- has found ways (or paid advisors to find ways) to pay the minimum amount of axes required.

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Brain chemistry

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We have known for a long time that dopamine is vital to the “reward” function in our brains. But, dopamine seems to have a much wider-ranging impact, than just this. After all, my grandfather, Sol Kuchlik, of blessed memory, was among the first treated with L-dopa (a form of dopamine) to counteract his Parkinson’s Disease symptoms. So, let’s see where we stand today (this is by no means an exhaustive review….).
Dr Tali Sharot, of University College of London, found that addicts overestimated the pleasure they would gain from taking heroin or gambling, because their dopamine system was dysfunctional. Dr. Sharot’s research group found, using imaging techniques, a signal in the brain linked to how much someone enjoyed a given experience. This signal let the group predict the choices that person made. It turns out that signal is dopamine.
It has also been found that ADHD patients had lower levels of dopamine receptors and transporters (both of these are proteins) in the (brain’s) nucleus accumbens and midbrain. Both of these are part of the limbic system, which is responsible for the emotions, as well as for motivation and reward. The more pronounced the ADHD symptomology, the lower the two protein levels. This is probably why stimulant medications (Ritalin, which is related to caffeine, is one such drug) treat ADHD symptoms- by raising the dopamine levels in the brain. I already discussed that raising dopamine levels affords Parkinson’s patients the ability to reach functional levels- no slurring of speech, better fine motor control, etc.
The findings also provide more reasoning as to why people with ADHD seem to be more prone to drug abuse and obesity. It turns out that they may be compensating for the deficient reward system that exists in their brain.
It also means that ADHD children may not be deliberately disrupting their classroom; it may just be a deficiency of the dopamine levels or receptors. (It also means that educators MUST augment the interesting/exciting levels in their classrooms to engage these kids and help them learn. I probably was one among them…)
[There was a study years ago showing that Parkinson’s Disease skips a generation. Maybe, this is why I was/am hyperactive- when I was growing up, attention deficit disorder and hyperactivity were separate syndromes. If Parkinson’s skips generations, AND if- since it can be treated with dopamine- this is related to lowered dopamine or dopamine receptor proteins, then it would make sense that hyperactivity or ADD could manifest itself in one such an individual.
It seems that dopamine also explains why some people are more creative than others. Dopamine receptor genes are linked to the ability to achieve divergent thought. We know (knew) that families with members demonstrating schizophrenia or bipolar disorders often have other members who were highly creative. The ability to make unusual or perhaps bizarre associations is found in both creative individuals and schizophrenics. Dr. Fredrik Ullen of the Karolinska Institutet used this knowledge in a study to demonstrate that the dopamine system in otherwise healthy, but highly creative people matched those of people with schizophrenia. Dr. Ullen found that creative people had lower densities of D2 receptors (there are five dopamine receptors of which were are aware; two are similar to D1, three are similar to D2). Schizophrenia, drug abusers, and now creative people all are affected by D2 receptors. The D2 receptors for creative types and schizophrenics are primarily found in the thalamus, the relay center that filters information prior to its arrival in the cortex (responsible for cognition and reasoning). The lower density of receptors means there is lower signal filters- and a higher flow of information- to the cortex. So, this means that thinking out of the box may really be the fact that the box is much bigger for creative types (little or less filtering of information to the cortex).
So, that’s the science, as we know it. But, here’s more food for thought. While my (ex)wife and I were “working on improving our relationship” (not, as the facts demonstrated), I was offered neurontin, a drug used to treat epilepsy, and in off-label uses for ADHD and schizophrenics. I also was offered the SAME drug by my physician during this same time period, as a means of correcting sleep apnea. While I was taking the drug, I noticed that my brain seemed to work slower- not really (since I did not get tested for this fact)- but I could discern a miniscule time lapse, during which I knew what I was going to say and do- before I did or said it. I now believe this drug may have been affecting my D2 receptors or changing my dopamine levels; maybe not enough to make a large difference, but enough for me to recognize the filtering mechanisms of the thalamus were altered.
I mention this because neurontin is NOT approved for these uses- but maybe it should be, because it does work for drug withdrawal, bipolar disorders (with much fewer side effects), and opiate withdrawal. With these new testing processes and results, it is time to reexamine many of our “hard and fast rules”…

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Opening Gambit

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I am somewhat trepidatious about this endeavor. It’s not that have nothing to say- if you know/knew me, you would understand that I am rarely at a loss for words. It’s that having a required schedule is intimidating. And, to be honest, writing about things that interest me may bore the heck out of you- and be too wide-ranging to make you want to come back.

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