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Fire is something that we are all familiar with. Everyone has experienced the simple fact that certain things can burn and in doing so are irrevocably changed. For mankind, fire has been an agent of change from the beginning of its use. A simple campfire can be thought of as a crucible where organic matter is destructively distilled and oxidized to carbon dioxide and water and inorganic matter is consolidated to metal oxides, carbonates, and phosphates.
The flame of a campfire sits in place over the fuel source, appearing to be stationary. But really, a flame consists of hot flowing gas. It is the combustion process that is stationary. A campfire is a kind of air pump pulling air in from the sides and lifting it upwards due to the buoyancy of hot combustion gases. As the gases rise, microscopic particles of glowing carbon are lifted above the wood giving the appearance of an envelope of glowing gas. Properly mixed propane or natural gas give a flame that has a bluish appearance with much less luminosity. Reading is possible by the light of a campfire. It is not so good by the blue flame of a camp stove.
A wood campfire will consume the wood down to ash. But before the wood becomes ash it can be observed to change from a fibrous solid to a glowing ember of black carbon. The early phase of burning is characterized by the evolution of abundant volatiles that distill into and energize the flame. Early gas lighting used the flammable gases distilled from coal to provide flame lighting for streetlights and home lighting. The problem with coal gas was that it was free of particulates so the brightness of the flame was poor. The problem of poor gas flame luminosity lead to invention of the limelight and the lantern mantle.
The lantern mantle was developed to overcome the problem of poor gas flame luminosity. A fabric bag soaked in thorium nitrate solution (with 1 % cerium) was dried and then attached to a burner. The gas ignition process burned the fabric and caused the thorium to calcine in place, forming a gossamer webbing of thoria ceramic. The heat capacity (Cp) of thoria is relatively low and the melting point is exceptionally high. Low heat capacity materials require less heat to raise the temperature to a given point relative to high heat capacity materials. The result is that a flame of ordinary heat can raise the temperature of the low Cp thoria to produce high luminosity. The ceria in the mantle dampened the green tinge of glowing thoria to produce a relatively natural light.
Thoroughly burned wood produces an ash that is largely inorganic in nature and at one time was considered valuable. Wood ash was used to provide potassium (potash) for early gunpowder formulations. In the early days of gunpowder, nitre (saltpeter or nitrate) was extracted from various sources and used with mixed results. Some nitre is found in wood ashes. Elsewhere, nitre would appear in damp patches of organic-rich earth as a whitish solid clinging to twigs and plant matter on the ground looking much like hoar frost. Caverns have long been a rich source of nitre. Mammoth Caves in Kentucky and Carlsbad Caverns in New Mexico were mined for their nitrate rich sediments long before tourists began tramping through them.
In 15th and 16th century England, nitre was systematically cultivated and extracted on nitre farms. A nitre farm had deep beds of manure and plant matter covered to shield them from rain. After a period of time, the nitre beds were transferred to a large basin and leached with water. The leaching solution was then boiled to dryness to give crude nitre. This crude material was carefully recrystallized to produce a white crystalline nitrate salt.
Nitre is actually a nitrate salt comprised of nitrate anion and a counter-ion like potassium, sodium, calcium, etc. In the early days of gunpowder, quality and reliability of the powder was highly variable. One of the variables was the extent to which gunpowder attracted moisture. Powder makers eventually learned that gun powders made from potassium nitre were much less likely to be passivated by humidity than those made from sodium nitre. It became common practice to combine wood ash with nitre extracts to produce what we now know to be potassium nitrate.
Nitre from the guano beds of Chile were rich in sodium nitrate while material from the great nitre deposits along the Ganges river in India were substantially potassium nitrate. Indian saltpeter was an important commodity of the East India Company and strategic material for the British Crown. Until the invention of the Haber-Bosch process of synthetic nitrogen fixation in 1909 and subsequent oxidation of ammonia to nitrate, the world’s guano beds and saltpeter veins were the major source of nitrates.
The first World War has been called the chemist’s war in part because of the tremendous casualty counts due to the mass implementation of nitroaromatic and nitroester explosives. Haber is notorious for his part in the use of war gases, but the production of nitrates from his process was of no less consequence.
Gas and oil in the ground is like money in the bank. We know where much of it is and it will only appreciate in value over time. Why are we so hasty to suck it out of the ground and burn it? Is it because we think we need it now? Extra supply will indeed drive global motor fuel prices down for a time.
A side effect of supporting continued cheap petroleum is that ever more infrastructure will be constructed that is dependent on cheap hydrocarbon energy and less infrastructure constructed for other forms of energy. Inevitably, supply will become scarce and a society constructed on a foundation of cheap petroleum energy will collapse.
This perilous proposition seems pretty simple in concept. What history shows is that a small number of highly dedicated people can swing the mood of a larger population. Many revolutions begin with a dedicated core who exploit some dissatisfaction to effect a desired change.
Right now we see a GOP that is driven by a minority of religious zealots wrapped in the flag and bent on an orgy of fratricide. What drives the Democrats is a mystery to me. They are a herd of cats.
Americans need to find meaning and a place in the world that does not involve urban warfare. We need to throttle back military spending and direct resources towards a sustainable market economy unified by peaceful common purpose. We are at a place in history where the Enlightenment is at risk of ending.
I just had a conversation with a colleague who is somewhat mainstream in his/her thinking. The question came up as to why can’t we be energy independent. What is taking so long with the electric cars and natural gas powered … everything? When can we break away from middle eastern petroleum?
In the public sphere, all I hear are the questioners seeking reassurance that there are energy forms out there that will allow us to maintain our current level of consumption. They rarely put it exactly that way, but that is the heart of the issue.
I think multiple generations of people have failed to appreciate the natural wonder of liquid hydrocarbons. The C7-C10 fractions of petroleum, whether directly from the ground or from a cat cracker or reformer, are the motive basis for most of our ground transportation. These liquid hydrocarbons are of a reasonably low vapor pressure and high enough boiling point to allow their use in everything from go-carts and lawn mowers to automobiles and caterpillars. Teenagers and grandmothers can pump hydrocarbons into an inexpensive and simple tank for use at ambient pressure and temperature. This liquid has a melting point low enough to make it flowable under nearly all earthly conditions.
The high energy density and the liquid state of gasoline is what makes it nearly perfect for propulsion. The energy density of gasoline is 34.8 mega-Joules per liter (MJ/L), as opposed to 21.2 MJ/L for ethanol.
Yeah, gasoline is cheaper per liter than the bottled water inside the convenience store. That perversion is just a temporary historical aberration. This will change.
Cosmically, hydrocarbons in the C7-C10 range suitable for automotive use are quite scarce in the local stellar neighborhood. Some small hydrocarbon molecules like methane have been spotted in the gas giant planets and on Titan. But for the most part, the only supply of hydrocarbons we have are found in porous deposits below the surface of the only place we can get to- Earth.
We should appreciate our hydrocarbon resources for the true natural wonder that it is and be a bit more reluctant to squander it. I doubt we’ll ever find a source of energy that is as cheap and convenient to use with such a high energy density. Battery technology may get close, but innovation there is a highly specialized art that is beyond the scope of most shade tree mechanics. Common lead acid batteries require material and energy inputs, like everything else, and have somewhat low energy density and a high weight penalty.
Lithium batteries, with their higher energy density require a variety of manufactured and relatively exotic substances. And, they require lithium which is fairly scarce, both cosmically and on earth. We really should be recycling lithium scrap. Seriously, we need to have great respect and appreciation for lithium as well. There really isn’t enough lithium to support everyone’s high energy density lifestyle.
According to news sources, BP is allegedly using a dispersant called Corexit EC9527A. According to the EPA this formulation contains water, propylene glycol, and 2-butoxyethanol, as well as an unspecified confidential additive.
I guess the question is, what purpose does this treatment serve? By dispersing the petroleum, I assume that the effect is to spread a given mass of petroleum into a larger volume of sea water by virtue of producing dispersed globules of oil-phase material. Does the increased surface area result in off-gassing of volatiles and subsequent submergence of the now denser oil phase? Or, will the dispersed petroleum simply drift into larger patches of oily water? If it enables an increased dispersion so that the currents can chaotically distribute the petroleum to a greater range of shorelines, is this treatment of any real benefit? Perhaps it is better in the long run to have a heavier coating on fewer beaches? Less acreage to scrape.
EPA is making noise about BP’s choice of Corexit. Seems to me that butyl cellosolve has been in the market for quite some time. There should be some information on its fate in the watershed. Judging from the map, the oil spill is near the dead zone around the mouth of the Mississippi River. So, until somebody gets some survey data, it’ll be hard to estimate the magnitude of the environmental insult of this event to the open ocean.
I do not understand what government officials were trying to do by saying that they might take over control of this spill. What is the government going to do to a petroleum discharge a mile below the surface? Call the Navy? Or Boots & Coots? As good as these guys may be, they’re land lubbers.
Let the folks at BP finish the job.
Hyperion Power Generation (HPG) company has announced the commercial development of their Hyperion Power Module. While there are numerous reports on the internet, it is more useful for curious and tech savvy folk to read the patent application (US 20040062340) for a detailed description of the device. While the idea has been knocking around for 50 years, it took the inventor, Dr. Otis G. Peterson, to work out the control issues for a safe, self regulating system.
The reactor uses the hydride of a fissile actinide like U-235 (as UH3 powder) at ~5% enrichment in U-238 to serve as a self-moderating nuclear pile. The marvels of chemistry, namely chemical equilibrium, play a large role here because the hydrogen content (as hydride) varies as a function of temperature. An increase in temperature of the UH3 leads to loss of hydrogen from the U to another hydrogen storing metal. Loss of hydrogen moderator leads to loss of reactivity and a downturn in heat generation. But the downturn in heat generation favors the return of hydrogen (as H2) to the uranium to make hydride. This causes the reactivity of the system to increase, so the rate of fission and heat generation rises as a result.
The system eventually reaches a steady state temperature where the rates of hydrogen gain and loss from uranium become equal and the rate of heat evolution reaches a steady output.
According to Table 1 of the appln, at 5 MW thermal the U-235 critical mass is 30 kg and at 50 MW thermal it is 215 kg. The table also discloses that at a loading of 30 kg U-235 the energy content is 78 MW years and at a loading of 215 kg U-235 the energy content is 540 MW years.
Of course, this is a patent and not a peer reviewed publication. But it was developed at Los Alamos so one would suppose it should have some credibility. The patent suggests that the reactor would be buried underground while in service. It is unclear if that is for shielding or security, or both.
The recent (re-)discovery of x-ray emission from unwinding scotch tape under vacuum makes me wonder how this phenomenon might be used. It would be interesting to see the emission spectrum. No doubt the physics boys at UCLA are pumpin’ out patents like pellets out of the back end of a rabbit.
The researchers report that duct tape does not provide the same effect as 3M Scotch tape. From the International Herald Tribune–
The tape phenomenon could also lead to simple medical devices using bursts of electrons to destroy tumors. The scientists are looking to patent their ideas.
And finally, there’s the possibility of nuclear fusion. If the energy from the breaking adhesive could be directed away from the electrons to heavy hydrogen ions implanted in modified tape, the ions would accelerate fast enough so that when they collided, they could fuse together and give off energy — the same process that lights the sun.
Good God. We’re extrapolating this finding into solutions for the energy crisis and cancer already!
The UCLA folks say that the Russians reported x-ray emission from tape in 1953, but nobody believed them. Could be a novelty-buster. Hmmm. I wonder if my Post-It notes will emit x-rays in vacuo too?
I’ll wager that at this very moment, a group of industrious Poindexters at two or three national weapons labs are trying to weaponize triboelectric x-rays. Project BIG STICKY.
Here is a “Novelty Buster” for the public domain– What would high Z additives in the tape composition do to the x-ray output? Seems to me that the heaviest atom naturally in Scotch tape would be silicon in the release backing layer. What if they grafted some heavy metal bearing monomers (metal chelates with a vinyl or other monomer moiety) into the composition somewhere? Would that affect the output spectrum?