A spoil tip (also called a spoil bank, boney pile, gob pile, bing, batch, boney dump or pit heap) is a pile built of accumulated spoil - the overburden or other waste rock removed during coal and ore mining. These waste materials are typically composed of shale, as well as smaller quantities of carboniferous sandstone and various other residues. Spoil tips are not formed of slag, but in some areas they are referred to as slag heaps.
The term "spoil" is also used to refer to material removed when digging a foundation, tunnel, or other large excavation. Such material may be ordinary soil and rocks, or may be heavily contaminated with chemical waste, determining how it may be disposed of. Clean spoil may be used for land reclamation.
Spoil is distinct from tailings, which is the processed material that remains after the valuable components have been extracted from ore.
Spoil tips may be conical in shape, and can appear as conspicuous features of the landscape, or they may be much flatter and eroded, especially if vegetation has established itself. In Loos-en-Gohelle, in the former mining area of Pas-de-Calais, France, are a series of five, very perfect cones, of which two reach 180 metres (590 ft), surpassing the highest peak in Flanders, Mont Cassel.
Slag is the glass-like by-product left over after a desired metal has been separated (i.e., smelted) from its raw ore. Slag is usually a mixture of metal oxides and silicon dioxide. However, slags can contain metal sulfides and elemental metals. While slags are generally used to remove waste in metal smelting, they can also serve other purposes, such as assisting in the temperature control of the smelting, and minimizing any re-oxidation of the final liquid metal product before the molten metal is removed from the furnace and used to make solid metal.
In nature, iron, copper, lead, nickel and other metals are found in impure states called ores, often oxidized and mixed in with silicates of other metals. During smelting, when the ore is exposed to high temperatures, these impurities are separated from the molten metal and can be removed. Slag is the collection of compounds that are removed. In many smelting processes, oxides are introduced to control the slag chemistry, assisting in the removal of impurities and protecting the furnace refractory lining from excessive wear. In this case, the slag is termed synthetic. A good example is steelmaking slag: quicklime and magnesite are introduced for refractory protection, neutralising the alumina and silica separated from the metal, and assist in the removal of sulfur and phosphorus from the steel.
Slag (a liquid) is a by-product of smelting ore. Slag, as a liquid, is distinguished from dross, which is a solid.
Welding slag (a solid) is a form of slag produced as a byproduct of some arc welding processes.
Slag may also refer to:
Slag is a 1970 play by British writer David Hare.Original cast: Lynn Redgrave, Anna Massey, and Barbara Ferris. Originally staged by the Royal Court. London
Slag is a biting satire in which the only characters are the three teachers of a tiny isolated girls' school. The play begins with a mutual vow reminiscent of the vow beginning the play Lysistrata in which Greek women vow to deny men sex to protest the Peloponnesian War. The three women teachers mutually pledge to abstain from sexual intercourse, in protest against the dominance and abusive treatment of women by men, epitomized in the slur against women as "slags." Conflicts among the teachers' different visions of radical feminism, different motivations, and different interpretations of and commitment to the vow become the grist for duplicitous dominant and abusive acts among them and distracts them from their teaching. Dominance and Feminism are ridiculed alike, while the number of pupils dwindles to zero in the resulting dysfunctional environment, leaving the three teachers to go their separate ways.
Heap may refer to:
Heap is a surname. Notable people with the surname include
The Heap is the name of several fictional comic book muck-monsters, the original of which first appeared in Hillman Periodicals' Air Fighters Comics #3 (Dec. 1942), during the period fans and historians call the Golden Age of Comic Books. The character was created by writer Harry Stein and artist Mort Leav, and revived in the 1980s by Eclipse Comics.
Similar but unrelated characters appeared in comics stories published by Skywald in the 1970s and Image Comics in the 1990s.
Following its debut Air Fighters Comics #3 (cover-dated Dec. 1942), the Heap reappeared as a guest character sporadically in that title. With its fourth appearance, in the by-then re-titled Airboy Comics vol. 3, #9 (Oct. 1946), it became the star of a backup feature. That feature continued until the final issue, vol. 10, #4 (May 1953). Other artists associated with Hillman's Heap include Jack Abel, Paul Reinman, and Ernie Schroeder.
In 1986, Eclipse Comics, having acquired rights to some Hillman characters, began publishing a new Airboy comic with the Heap as a supporting character. The Heap also appeared in the Eclipse title The New Wave, where the creature was considered by some members of that group to be a member. Eclipse Comics went bankrupt and ceased operations in the 1990s. Image Comics purchased the Eclipse assets, including the Heap.