Cover Slide
Slide Slide %& %& Brie$ Brie$ 'ist 'istory ory
Good morning Dr Pocock and Fellow students. My name is Christopher Perumal and my colleague here is Kashmeel Bisseru. he metallurgical process we we will !e presenting today is the Blast Furnace "ron Production. Production. #hich converts "ron ore into high purity iron metal used $or steel production which is !eyond the scope o$ our presentation. here here are are two two proce process ss route routes s avail availa!l a!le e $or $or the the produ producti ction on o$ o$ steel products( the !last $urnace with o)ygen steelmaking and the electric arc steelmaking route. Blast $urnace processes usually produce *at products and use coke and coal as the reductant sources and sinter( pellets and lump ore as the iron& !earing component. BF+s produce ,- mln ton ( /0F --%mln "t is speculated that the production o$ iron $rom iron ore !egan sometime a$ter % B.C. in South 0sia where iron $ound use in weapons and various tools. his was a conse1uence o$ it replacing !ron2e due to it !eing harder and dura!le when alloyed with car!on. here$ore( iron $ormed the material !asis o$ human civili2ation in /urope( 0sia and 0$rica. he ne)t milestone in the the production history is that o$ 3wrought iron+ produced !y !lacksmiths during the "ron 0ge. his involved heating iron ore in a charcoal 4re and then removing the pasty mass in order to hammer it. his would compact the metallic particles. By the late middle 0ges( 0ge s( /uropean iron makers had developed the !last $urnace 5large( countercurrent( vertical( chemical reactor6 in which a !last o$ air was used to intensi$y com!ustion. Molten cast iron 5which typically contained 7 to -.8 9 car!on6 would !e produced at the !ase o$ the $urnace and directly cast into molds. "nterestingly( pig iron was coined during this time !ecause the molten mol ten iron running into a sand trough which would $eed smaller troughs resem!led a sow suckling a litter o$ piglets. he cast pig iron could !e used to produce pots( pans and many other goods. :ver the course o$ the %th century( heath diamters increased !y three to $our times( with the annual production p$ increasing 7 to - $old. his is !ecause the ore ore !urden developed $rom using using lump ore and coke to sinter and pellets. he reductant developed as well( $rom only using coke to using in;ectants through the tuyreres.
Slide 7&
Steel productio production n re1uires re1uires a certain certain 1uality 1uality o$ hot metal with compositions o$ silicon( manganese and phosphorous within speci4ed ranges and high temperatures. he per$ormance o$ !last $urnaces is increased !y charging iron ore in the $orm o$ sinter rather than directly as ore. he sintering process consists o$ mi)ing iron ore with coke !ree2e $ollowed !y a com!ustion source to promote sur$ace melting o$ the ore
particles. Between = and > 9 coke !ree2e is used and the mi)ture is spread on a travelling grate and ignited !y a !ank o$ gas !urners 4ring downwards $rom an ignition hood Slide - ?
0 !last $urnace can !e descri!ed as a countercurrent chemical reactor in which the charge o$ the raw materials o$ limestone( coke( sinter and iron ore *ow down the sha$t whilst the hot !last air which are gases are $ed up the $urnace length. "ndustrial si2e $urnaces are usually !etween % to %8 m high and @ to >- m in diameter 5Gilchrist( >,A,6. he !last $urnace operates at temperatures ranging !etween A= and >88 ℃ and is controlled !y the rate at which air is !lasted and
the amount o$ coke that is charged into the $urnace 5'a!ashi( >,A@6. "t takes the raw materials a!out @ to A hours to react and descend to the !ottom o$ the $urnace 56. here are dierent 2ones that the length o$ the $urnace can !e divided into and they include the hearth( raceway( !osh( !elly( lower sha$t and upper sha$t. /ach 2one represents a particular temperature range !ut also can !e identi4ed !y the nature o$ the reactions that occur within it. he charge is usually $ed !y a conveyor system that uses a skip !ridge as the transporter. he charge is $ed into a charge hopper which regulates the delivery o$ the charge along with the pressuri2ed gas seal system which mani$ests itsel$ in the $orm o$ a dou!le !ell. Due to the high temperatures present in the $urnace( the inside walls o$ the structure are re$ractory lined and it must !e ensured that no reactions with the slag constituents will occur that may cause erosion o$ the walls. he metal and slag layers that are produced a$ter the reactions sit in the hearth o$ the $urnace and there$ore need to !e removed. 0 taphole is a means o$ o!taining the molten iron and the slag. he taphole is !uilt into the re$ractory lining o$ the !last $urnace. 'ot molten iron is generally tapped every three to 4ve hours into ladles or re$ractory lined railcars $or transportation to the su!se1uent parts o$ the process such as the desulphuri2ation plant. "n terms o$ the hot !last air which is preheated in the stoves and then delivered through the !ustle pipe which provides a regulated *ow o$ air delivery into the tuyeres. he tuyeres are a cooled copper conical pipe num!ering up to >% in smaller $urnaces and up to -% in !igger $urnaces though which pre& heated air5 up to more than >%C6 is !lown into the $urnace. 0$ter the reactions have occurred typically the o&gases contain harm$ul emissions and dust particles which cannot !e ;ust vented to the atmosphere as it would !e in !reach o$ strict
environmental legislature. 'ence the $urnace has closed gas uptake pipe structure situated at the top that will transport the gas via a downcomer to a dust catcher and a Eenturi washer that aims to clean the gas such that it can !e used elsewhere in the plant.
