View Single Post
Old 14th February 2012, 02:10 AM   #1466
Christopher7
Philosopher
 
Christopher7's Avatar
 
Join Date: Aug 2006
Posts: 6,538
Originally Posted by Sunstealer View Post
All low alloyed or plain carbon steels develop mill-scale during the rolling process at the rolling mill due to the temperatures at which the steel is formed into shape by rolling. Mill-scale is the formation of iron oxide on the steel's surface and is typically 1mm thick or less.
1mm = 0.04 inches

Quote:
Hydrocarbons when burnt will produce CO and CO2. It is well understood that Carbon will reduce iron oxides below the melting point of Fe and below the oxide melting temperature. Mankind has been using this process since the Iron Age. Anyone who has looked into Iron production will know this.

See Bloomery.

In operation, the bloomery reduces the iron oxides in the ore to metallic iron, without melting the ore; this allows the bloomery to operate at lower temperatures than the melting temperature of the ore.
iron oxide becomes metallic iron at roughly 1250C, almost 300 degrees below iron's melting point of 1538C
http://en.wikipedia.org/wiki/Smelting

Iron ore:
magnetite (Fe3O4), hematite (Fe2O3), goethite (FeO(OH)), limonite (FeO(OH).n(H2O)) or siderite (FeCO3).
http://en.wikipedia.org/wiki/Iron_ore

Melting point of magnetite/Iron oxide (Fe3O4) 1538oC - 2800oF
http://www.espimetals.com/index.php/...on-oxide-fe3o4

Melting point of iron oxide/rust (Fe
2O3) 1566oC - 2850oF
http://en.wikipedia.org/wiki/Rust
http://en.wikipedia.org/wiki/Iron%28III%29_oxide


Iron must melt and then be atomized to produce iron spheres.

The bloomery process does NOT melt the iron in the ore and therefore it cannot produce iron spheres.


Quote:
The production of "iron rich micro-spheres" in such a situation is to be expected.
Wrong, as noted above.

Quote:
We also have environmental studies from coal and municipal solid waste (MSW) incinerators that operate below the temperatures required to melt pure Fe. Those studies indicate the presence of such "iron rich microspheres" produced from Fe, its oxides and man-made alloys that are subjected to similar temperatures and reducing conditions that were present in the WTC 1,2,7 and other fire affected buildings.
Fly ash is one of the residues generated in combustion, and comprises the fine particles that rise with the flue gases.
http://en.wikipedia.org/wiki/Fly_ash

Fine particles: Particulates also known as particulate matter (PM), suspended particulate matter (SPM), fine particles, and soot are tiny subdivisions of solid matter suspended in a gas or liquid.


Any microspheres created as part of fly ash from burning office contents would fly away in the smoke along with all the other particulate matter.
Christopher7 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top