You can tell a slip by the way the charging slows down. A roll is where the burden is too loose and a high hot blast pressure from below creates turbulence and mixes the burden, again pressure rises sharply and bleeders open. You can tell you had a slip by the problems with casting for the next 4 to 5 hours.
As the burden moves down through the furnace approx. 2000 chemical reactions occur. A slip is believed to happen when a complex compound is formed that has a higher melting point than the temperature in that level of the furnace. This material hangs up, while Fe2O3 is reduced beneath and creates a void. The frozen material soon heats up and melts, and falls sometimes up to 25 creating a fast rise in pressure that opens the dirty gas and explosion bleeders.
A furnace slip and a furnace roll are not the same thing. Material make-up in a blast furnace is called a burden, and is developed to deal with the particular raw materials available due to cost and location. Every blast furnace in the world uses a different burden because of many reasons. Coke, iron ore and flux, the main raw materials, are charged in layers to optimize production.
@SMsmelter The hot air is blown in with quite some pressure, so when the top opens a lot of gas will blow out (the furnace is 13 meters in diameter and some 50 meters in height? correct me if I'm wrong!). Part of the gas will be combustible CO (carbon monoxide), only some tiny fragments of burning coke are needed to light it! This happened somewhere in 2007, last year the other blast furnace (#7) did something similar, but the hatches closed very quickly.
Most of the cars next to the blast furnace were black, I had to run inside a building but was some 5 seconds too late so one sleeve of my white shirt was also black... The company provided coupons for the carwash...
Its a term for when the burden inside the furnace shifts (rolls), It creates a lot of top pressure, pops the bleeder and spews out a bunch of gas and even some material at times. Not good for a furnace but happens sometimes.
You can tell a slip by the way the charging slows down. A roll is where the burden is too loose and a high hot blast pressure from below creates turbulence and mixes the burden, again pressure rises sharply and bleeders open. You can tell you had a slip by the problems with casting for the next 4 to 5 hours.
428blown 2 years ago
As the burden moves down through the furnace approx. 2000 chemical reactions occur. A slip is believed to happen when a complex compound is formed that has a higher melting point than the temperature in that level of the furnace. This material hangs up, while Fe2O3 is reduced beneath and creates a void. The frozen material soon heats up and melts, and falls sometimes up to 25 creating a fast rise in pressure that opens the dirty gas and explosion bleeders.
428blown 2 years ago
A furnace slip and a furnace roll are not the same thing. Material make-up in a blast furnace is called a burden, and is developed to deal with the particular raw materials available due to cost and location. Every blast furnace in the world uses a different burden because of many reasons. Coke, iron ore and flux, the main raw materials, are charged in layers to optimize production.
428blown 2 years ago
negli altoforni di Taranto queste cose nn succedono...
we are the best in the world!!!!
deol80 2 years ago
When the futnace is empty and you open the bleeder happens this, but if you put N2 !!!
lh1968hristov 3 years ago
@lh1968hristov What does N2 means?
SMsmelter 1 month ago
@lh1968hristov When the furnace is empty and if you open the bleeder black smoke comes out.
Is that why, when they are shutting down the furnace the black smoke comes out?
Do operators (when shutting down furnace) open the bleeders to resel furnace gas?
Or becasue the furnace is not totally filled with burden (when shutting down furnace) and top pressure opens bleeders automaticaly?
SMsmelter 1 month ago
@SMsmelter The hot air is blown in with quite some pressure, so when the top opens a lot of gas will blow out (the furnace is 13 meters in diameter and some 50 meters in height? correct me if I'm wrong!). Part of the gas will be combustible CO (carbon monoxide), only some tiny fragments of burning coke are needed to light it! This happened somewhere in 2007, last year the other blast furnace (#7) did something similar, but the hatches closed very quickly.
BartManNL 1 month ago
Most of the cars next to the blast furnace were black, I had to run inside a building but was some 5 seconds too late so one sleeve of my white shirt was also black... The company provided coupons for the carwash...
BartManNL 1 month ago
Furnace rolled. Happens. lol
Ch1ck3nF1ght 3 years ago
Furnace rolled? wa does tha mean i have seen the blow outs and the bleeders goin for it, but never heard of furnace rolled.
DrSinfulness 3 years ago
Its a term for when the burden inside the furnace shifts (rolls), It creates a lot of top pressure, pops the bleeder and spews out a bunch of gas and even some material at times. Not good for a furnace but happens sometimes.
Ch1ck3nF1ght 2 years ago
Arh i know it as burden slips
DrSinfulness 2 years ago
Yeah i kinda thought you might know it by a different name. haha.
Ch1ck3nF1ght 2 years ago