As I said before, FJ babbles way too much about "courage" for a filth merchant who presumably writes under an alias and desperately tries to rationalize away, with elaborate technical arguments, facts that for some reason don't fit his ideological articles of faith. If he is not interested in continuing this forum exchange, that's all the better. I shall then find more time for a detailed analysis of his "notes" on the HC blog site, a more productive way to spend my posting time until MGK publish their response.friedrichjansson wrote:I will probably not respond any further after this, unless Roberto musters the courage to write something on this topic on his blog.
Thanks for the lecture about the difference between barbecuing and grilling, which would have been better without the "ignorance" and "desperation" rhetorical BS.friedrichjansson wrote:1. Barbecue drip pans
Roberto points out that barbecue drip pans can recover fat that does not burn; also points out that this occurs in ovens. Well, of course. We all know that you can put a drip pan under a piece of meat as you roast it and collect the drippings (provided you make a number of slits in the skin). Why doesn't the fat burn? Because the temperature isn't high enough, of course. Cremation temperature is >600 C, cooking temperature is much lower; that this makes a difference for the combustion of fat is obvious. Another reason it that it isn't exposed to flame, which means it will need to reach its autoignition temperature to combust.
What about barbecue? Isn't the fat at least exposed to the flame there? Hardly. In his typical ignorance, Roberto has confused grilling and barbecuing. What's the difference?
You can find a more detailed taxonomy here, which gives a BBQ temperature of 102 C. That this is totally unlike a cremation pyre is self-evident.The Difference Between Grilling and Barbecue
This is a question that is asked by many, but not widely known or understood. A lot of the confusion lies in the fact that people often use the same piece of equipment for grilling as they do for barbecue. The two are however antithetical to one another.
Grilling is a high heat cooking method. Food is cooked directly over the coals and is normally ready in a matter of minutes. Grilling temperatures are usually in excess of 500 degrees Fahrenheit, and food is cooked close to the heat source. The high heat chars the surface of the food, seals in the juices and creates a smoky caramelized crust.
Barbecuing by contrast lies at the opposite end of the spectrum from grilling. It is a long, slow, indirect, low-heat method that uses smoldering logs or charcoal and wood chunks to smoke-cook the food. Barbecue temperatures are usually between 200 and 300 degrees Fahrenheit. This low heat generates smoke, and this smoke gives barbecue its characteristic flavor. The heat source is often separate from the cooking chamber, which contains the actual food.
This is what the drip pans Roberto is thinking of look like.
Note the indirect heat - the fat never touches the fuel. The lid would be closed, and a slow fire maintained, which would keep the temperature a little over 100 C for several hours. It's a sign of Roberto's desperation that he is seriously trying to compare this to a pyre capable of cremating hundreds or thousands of bodies.
So when one does not barbecue but grill at temperatures "usually in excess of 500 degrees Fahrenheit" (260º Celsius), what happens to the fat?
Even when grilling it is possible to keep fat from dripping into the flames and catching fire there by slightly sloping the grill as shown here:
Another method, which allows for grilling even bacon, is described as follows (my translation):
Grill the stripes of bacon on the grill's cool site, where there are no coals. For when the bacon begins to cook, the fat drops down onto the grill, and if you're frying bacon upon the coals at great heat, the dripping fat burns and there are huge flames. In order to avoid this you should grill the bacon only over indirect heat. The fat still drops into the grill, but as there are no coals below there are almost no flames.
Probably the reason why it was possible to collect some of the fat from the Birkenau pyres was that the pyres didn't burn uniformly throughout their whole length and width during the whole cremation process. While in some parts there might be temperatures around or above 600º C and hot embers lying at the bottom of the cremation pit, in other parts the fire was not so strong - as becomes apparent from eyewitness testimonies, after a certain time the fire had to be constantly tended by pouring liquid fuel over it - and fat exuding from the corpses hit parts of the cremation pit with no glowing embers in them and ran from there to the collection pit.
What happens to fat in cremation ovens? Apparently it isn't necessarily all consumed, at least when the crematorium is not professionally operated, as is suggested by the following text (emphasis added):
http://photos.whittierdailynews.com/201 ... -6-2013/#7Oscar's Ceramics on Darwin Road in Hesperia, a plant that purportedly was making ceramic panels for space stations, was instead a secret cremoratorium. Investigators on Jan. 20, 1987 found two large kilns, each more than half filled with the burning bodies of human beings. Human bones and ashes partially filled eight 55-gallon garbage cans. The thick, dark liquid of human body fats and oils covered the floor, running out the back door to a makeshift pit. Pasadena Crematorium, located in Mountain View Cemetery in Altadena. The Altadena crematorium was gutted by fire Nove. 23, 1986, yet the cremations credited to the facility continued. David Sconce was operating an unlicensed crematorium in Hesperia. (Photo by Walt Mancini/Pasadena Star-News )
Assuming that FJ's calculations are correct, that the fire occupied the entire pit and had the same temperature throughout, and that all bodies - including such added to the pyre later, as shown here and here - were subject to that temperature from the start of their incineration. Bodies not in direct contact with the fire due to the pyre's not burning uniformly might for some time be subject to a grilling effect such as shown in the picture below from the aforementioned grilling site:friedrichjansson wrote:2. Sustained combustion of fat
In a pool fire in a container, it probably won't until the fuel is exhausted, since the fire keeps it hot. However, no general statement is possible, since the behavior will depend on the geometry of the fire, as well as the nature of the surrounding materials.Roberto wrote:And how long does it take for temperature to cool down below the flash point?
In any event, the question is irrelevant, because as shown in the first posts in this thread, the fat would all be consumed in the fire.
Instead of blowing straw-men, FJ should address this:friedrichjansson wrote:3. Conduction
Roberto has asserted that grease fires in pans only continue to burn because the conductive properties of the metal keep the fat hot. I pointed out to him that good thermal conductors help heat flow in both directions, and that in this kind of situation the conductor was helping the heat flow away from the fat. Unbelievably, he still doesn't understand this. In failing to understand this simple fact, Roberto is rather like the satyr in the fable of the man who blew both hot and cold.
Mattogno made a grievous error by placing the lard in a rather large aluminum pan. Wood has a heat conductivity of 0.04 Joules/second * meter * degrees Celcius (J/s*m*C). Body fat has a thermal conductivity (k) of 0.20 J/s*m*C. Aluminum has a thermal conductivity (k) of 240 J/s*m*C. This is an absolutely astounding difference. Aluminum is about 6,000 times (6,000x) as efficient heat conductor than wood and 1,200 times (1200x) as efficient conductor of heat as body fat. Again rather sloppy work. Mattogno has inserted a terrific heat conductor into the experiment in direct contact with the combustion target. I do NOT recall from the eyewitness accounts the mention of aluminum in the incineration pits in direct contact with the bodies. The eyewitnesses talk about pits full of wood and bodies both of which are rather lousy conductors of heat. Again he has allowed his sloppy experiment to stray away from the eyewitness testimony.
This above point may not seem significant to those of you without scientific background, but let me give examples of its import. Do NOT do this experiment at home. Just consider it. Heat your oven to 400 F. Bake an angel food cake until done. Remove the angel food cake from the oven. Place you hand on the cake. It is certainly very warm but it doesn’t burn you. Now place your hand of the metal cake pan (DON”T actually do this). The metal cake pan will give you a whopper of a burn very quickly, but the cake didn’t. The cake is a lousy conductor of heat so you don’t get burnt, but the metal pan is a great conductor of heat and has a high capacity of heat so a great deal of heat gets delivered to your hand very quickly. Ouch….a rather nasty burn.
Another example. Do you have a Weber charcoal grill. Have you noticed the handle on the metal coal basin and the metal lid are wooden. My barbeque tools are also made of metal. But they have wooden handles. Even when the cooking coals are red hot I can maneuver my grill around the patio by grabbing the wooden handle. I wouldn’t want to grab the metal basin though. Same with the metal lid. It is NOT advised to grab the metal lid, but no problem in grabbing the wooden handle and lifting the lid for a peak to see if the burgers are done.
Now how does the insertion of the large aluminum pan into the experiment make a difference???? With the large pan a great quantity of heat from the fire is very rapidly conducted to the small amount of lard. As this heat warms the lard the aluminum pan cools just a little (after all, the heat is moving from the aluminum pan to the lard). But because the aluminum pan is such a terrific heat conductor it immediately captures more heat from the fire and in turn immediately delivers it to the melting lard. This is the express lane to ignition of the target matter.
Let's take the deep fat fryer in the video. How long do you think was "too long" there?friedrichjansson wrote:4.Depends on the details of your equipment, obviously.Roberto wrote:Question you didn't answer:
You can tell me something more about this interesting experiment. How long will I have to keep the stove burning at what temperatures for the lard to auto-ignite? I'm asking because the fire in this video happened because a deep fat fryer was left on "too long".
Why not? Did the witnesses say anything about how the fat left the pyre?friedrichjansson wrote:5. Spattering
Really, this issue is stupid. Spatter does not match the witness descriptions at all.
Why so, and what "very small" percentage of 10 tons of fat did you have in mind?friedrichjansson wrote:There's no way to estimate the amount of spatter without details on the geometry of the pyre, but it would certainly be very small.