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Tillverkning av cement (Elektrifiering/elektrisk drift)

av QZGBT5, Friday, January 25, 2013, 14:05 (4419 dagar sedan) @ Stefan Isaksson

SJ:s hundraårsbok har en del att säga om saken.

Den springande punkten var inte brist på järnmalm utan brist på kol för att tillverka stålet. Det var ett viktigt skäl till att man prövade betongstolpar.

Dock anger 100-årsboken att när man räknade på saken, var kolåtgången nästan lika stor för betongstolparna - det går ju som bekant åt kol för att tillverka cement...

I vilket skede vid tillverkning av cement måste man använda kol?

/Bengt

Hela tråden:

 

Time: 260
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Time: 1115
SELECT COUNT(*) FROM mlf2_entries LEFT JOIN mlf2_akismet_rating ON mlf2_akismet_rating.eid = mlf2_entries.id LEFT JOIN mlf2_b8_rating ON mlf2_b8_rating.eid = mlf2_entries.id WHERE (mlf2_akismet_rating.spam = 1 OR mlf2_b8_rating.spam = 1)
Time: 1233
SELECT COUNT(*) FROM mlf2_entries LEFT JOIN mlf2_akismet_rating ON mlf2_akismet_rating.eid = mlf2_entries.id LEFT JOIN mlf2_b8_rating ON mlf2_b8_rating.eid = mlf2_entries.id WHERE category IN (0, 4, 5, 6, 7, 8, 9, 25, 14, 23, 19, 22, 24, 10, 21, 11, 12, 13, 15, 16, 26, 18, 20, 27) AND (mlf2_akismet_rating.spam = 0 AND mlf2_b8_rating.spam = 0)

Total time: 2617