Pyramids

bas-relief in tomb of block mouldingSlide_0042_FullPhoto of ceiling in Pyramid Chamber

The Pyramids were not built with craved large blocks of limestone transported from a distant quarry by a huge number of slaves (an impossible task in the construction time of 20years for the Great Pyramid). The blocks were actually poured on site into molds as shown in the above wall painting from a tomb dating to around the same time as the pyramids. The poured material was like a concrete or mortar made up of an aggregate and a binder which was mixed with water and set over time. The matrix limestone (CaCO3 which contains fossils) came from a young soft deposit in a close-by wadi. The binder was a geopolymer material made from Natron (sodium carbonate-NaCO3), lime (CaO ), wood ash (contains some KOH) and kaolin clays. The mixture of Natron and lime with water gives calcium carbonate (CaCO3) and caustic soda (NaOH) which in turn reacts with the clay. The material sets and strengthens over a few days so the mold can be stripped and more adjoining blocks poured. As the material dries it becomes indistinguishable from natural limestone. The Great Pyramid had a veneer of polished marble slabs which did come from a distant quarry. The slabs were held in place over the blocks by a mortar which can be identified by chemical analyses as different from the marble slabs and the molded limestone blocks.
The builder of the Pyramids was Imhotep. Imhotep (en.wikipedia.org…Imhotep) was not only one of the first recognised Civil Engineers but also one of the first (and great) chemical engineers (the first was probably the person who discovered Cupellation to separate silver from lead around 5000BC).

The Wiki entry about Imhotep mentions he was Maker of Vases in Chief. Look at this vase

Egyptian Cast Gneiss Vase

No one could carve this even today with diamond tipped tools. It has been molded from a thin sheet of geopolymer bonded material with the edges gently folded over. It was then probably fired at a low temperature (around 300C) to set.

Thermodynamics and Heat Transfer

Posted this at http://tallbloke.wordpress.com/2014/04/25/critic-of-official-climate-science-tackles-er-sceptics/

I have not bothered to comment on Spencer’s blog because it is difficult to point out errors to someone who does not fully grasp engineering science. Lets start with Thermodynamics. There are some good books around such as Smith, Van Ness & Abbott “Introduction to Chemical Engineering Thermodynamics” McGraw-Hill 1996. Perry’s Chemical Engineering Handbook (McGraw Hill) has a good summary – Section 4 Thermodynamics. There are 5 postulates of Thermodynamics
1/ “There exists a form of energy known as internal energy, which for systems at internal equilibrium is an intrinsic property of the system functionally related to its characteristic coordinates
2/ The total energy of any system and its surroundings is conserved. (Also known as the 1st law of thermodynamics)
3/ There exists a property called entropy, which for systems at internal equilibrium is an intrinsic property of the system functionally related to the measurable coordinates which characterize the system. For reversible processes changes in this property may be calculated by the equation dS=dQ/T
4/ The entropy change of any system and its surrounds, considered together, resulting from any real process is positive, approaching zero when the process approaches reversibility (Also known as the second law of Thermodynamics)
5/ The macroscopic properties of homogeneous PVT systems at internal equilibrium can be expressed as functions of temperature, pressure and composition only.
Section 5 of Perry’s Chemical Engineering Handbook is called Heat and Mass Transfer.
It is an extensive section which requires a good knowledge of maths and makes considerable reference to dimensionless numbers of which (it appears) no climate scientist has any knowledge.
I just point out that there are four types of heat transfer a) conduction, b) convection with sub forms of natural and forced c) phase change and d) radiation.
With respect to radiation it should be pointed out that the Stefan-Boltzmann law/equation applies to surfaces in a vacuum. Engineers use emissivity factors and view factors (corrected by temperature ratios) with the S-B equation to obtain estimates of radiation heat flux in furnaces and heat exchangers plus other equations for convective heat flux.
Finally, instruments which measure temperature need to be properly calibrated and zeroed. (I have measured flame temperatures as high as 3500K) There are no instruments that directly measure radiation flux. Those that supposedly show a result from some mathematical equation need to be understood, calibrated and zeroed. There can be no radiation heat flux from a cool gas 1000′s m in the atmosphere flowing to a surface which is at a higher temperature. The basic premise of AGW with regard to CO2 is nonsense.

CO2 in the atmosphere

Ernst-Georg Beck was a honest hard working Scientist. He died of cancer in 2010 but his excellent web site, which has many articles and references, is kept up by his daughter.

Please visit it http://www.biomind.de/realCO2/realCO2-1.htm

Around 1940-1942 several scientists measured CO2 in the atmosphere at levels close to the present in 2011. This can be seen in the graph on the home page of Beck’s web site. One of the Scientists was W Kreutz who made continuous measurements of CO2 three times a day plus other weather related parameters (temperature, radiation, rainfall humidity, wind direction and speed etc) for one and half years 1939-1941. During this period he also made more frequent measurements over shorter periods such as eight days. It is a pity that so-called climate scientists have not made such thorough ( and accurate) measurements of all parameters which are an input (eg radiation) or a result ( eg temperature, humidity, CO2 etc) of weather changes. Kreutz was a chemist who was interested in conditions affecting plant growth. His measurements were published in a Botany Journal and have been overlooked in Climate research until brought to attention of the world by E-G Beck. Beck has scanned the individual pages of the article and that can be downloaded from his web site.

Below is a partial translation of the article by a Dutchman Andre Bijkerk. I can not remember how it came into my file but I hope he does not mind me posting it here.

http://cementafriend.files.wordpress.com/2013/01/co2-1939-40-kreutz_english.pdf

 

Methane good or bad

Natural Gas, More Polluting than Coal? Only According to the IPCC. A Note from Cementafriend

METHANE is the major component of natural gas (>94 percent) and coal seam gas, which are claimed to be good clean fuels on the basis they have a lower carbon content than coal or oil.

Is this the same methane from the backsides of farting cows (or to a greater extent from the mouth of ruminants) that is considered to be a bad greenhouse gas and 21 times more potent than carbon dioxide? And the same methane that when escaping as a fugitive (lost through leakage) gas from coal mining is considered bad?

This is contradictory.

In the following note I consider how potent methane actually is as a greenhouse gas and then compare energy equivalents per heat absorbed all in carbon dioxide equivalents.

Methane (CH4) only absorbs significant radiation from the earth’s surface at around 288K, in the small range of 7.4-7.8 micron. By eye the absorption is less than one tenth that of CO2, see the Diagram (double click on the image for a larger view).

Yet we are continually told that methane is 21 times more potent as a greenhouse gas than CO2.

This is what the IPCC tells us.

I have contacted various respected climate scientists (on both sides of the AGW debate). But no one has been able or wished to provide a definite answer.

So I have made my own assessment.

When one burns CH4 in air the chemical reaction is:

CH4 + 2O2 > CO2 + 2H2O.

That is, methane combusts to form carbon dioxide and water vapour.

Water vapour absorbs IR close to 100 percent in the range 4.5 to 8.0 micron (completely overlapping CH4), raising from zero at about 12.5 micron to close to 100 percent at about 16 micron and then 100 percent above 16 micron into the microwave range, see the Diagram.

CO2 is only a significant IR absorber in the range 14 to 15.5 micron (with a peak at 14.8 micron) but there is an overlap with water vapour.

From a visual inspection of the amount of radiation transmitted, Diagram 1, it can be justified that the e-m absorption of water vapour in the range 4 to 40 micron is at least 10 times that of CO2.

So, CH4 equivalent IR absorption = (1* CO2 + 2*10*CO2) =21*CO2

In other words, that figure of 21 times more potent is actually calculated in water vapour equivalent.

So we have established that methane, the major component of natural gas, when it is burnt produces quantities of greenhouse gases. But it is called a green fuel. Why?

It is common practice for energy supply companies to give the energy content on a gross basis but in reference texts such as Perry’s Chemical Engineering Handbook the heats of formation and combustion energies are given for net and gross energy.

The gross energy includes the heat of condensation of water (2.3 GJ/t H2O) which in combustion processes is not available for heat transfer. To compare fuels, only the net heat should be used.

Reference values from Perry’s Chemical Engineering Handbook for the net heat of combustion are Hydrogen (H2) =120 GJ/t, Methane (CH4) =50 GJ/t, Ethane (C2H6) = 47.5 GJ/t, Carbon (C) =32.8 GJ/t, Carbon monoxide (CO) = 10.1 GJ/t

For a typical black coal with an ash content by weight of 15 percent and a delivered moisture of 7 percent and a typical natural gas with 94 percent methane, 2 percent ethane equivalent, and 4 percent CO2 by volume the following applies:

So, if we apply the IPCC methodology for methane as a greenhouse gas, to methane as a fuel, you more than double the emissions for the same energy when natural gas is used instead of coal.

Now let’s go back to the fugitive methane. In Perry’s Chemical Engineering Handbook the following can be found:-
a) ignition temperature in air =650C
b) lower limit of flammability (% gas in mixture)= 5
c) higher limit of flammability (% gas in mixture)= 15

It should be very clear that methane released into the air does not burn but to summarize this point for methane in the atmosphere a) at 1,7ppm it is below the flammability limit and b) everywhere in the atmosphere is below the ignition point (this even applies at points of high emission such as a swamp, landfill vent etc)

The level of methane in the air has been measured since at least 1980 and data from ice-cores is also available showing increases in CH4 up to the year 2000 and then levelling and possibly declining at approximately 1730 ppb (1.73ppm) (see Tom Quirk in Energy and Environment).

The existence of CH4 in the atmosphere is proof that CH4 does not burn.

There is a natural cycle for methane with sources and sinks. It is slightly soluble in water (oceans) and is absorbed by some plants and algae and bacteria. It can be oxidised in lower atmosphere by ozone (produced by lightning, electrical arcing such as welding, and breakdown of NOx emission by sunlight) such as

CH4 + O3 > CH3OH (methanol) + O2.

The methanol and other –OH radical compounds are highly soluble in water. This is part of the natural cycle. The removal of ozone in the lower atmosphere has health benefits.

In summary, if one is concerned about greenhouse gases then the statement that natural gas or coal seam gas (methane CH4) is a friendlier fuel than coal (i.e. good), and the statement, that fugitive methane (CH4) from coal mining or animal emissions is bad, are both false.

References

1. Perry’s Chemical Engineering Handbook 4th Edition & 7Th Edition

2. Tom Quirk has an article in Energy & Environment July 2010 (abstract http://multiscience.metapress.com/content/m7337203x121g1hh/?p=42ddd03a121f46138f01ccf97183c9ff&pi=4)

3. The source of the diagram http://en.wikipedia.org/wiki/Absorption_band

Disclaimer

My superannuation fund has shares in Origin Energy which produces, distributes and burns (in power stations) natural gas and coal seam gas & shares in BHP-Billiton which produces oil, gas and coal – I am pragmatic.

Chart from comment 3 below- my thanks Sunsettommy