Manganese silicon alloy is the good deoxidize dose in puddling industry production, produce in nonferrous metal in making, total production value occupies the 2nd, it is the relatively crucial category alloy in nonferrous metal. Subsequently heat of hot stove of mine of manganese silicon alloy ceaseless development, the molten iron that gives wears bottom safety accident to also jump over bigger, analyse of hearth of alloy of discussion manganese silicon to spend ascendant cause, then concrete analysis hearth burns the cause that wears safe accident, reduce and prevent hearth to burn wear safe accident, make what expend with cost decrease to the smooth production of manganese silicon alloy have crucial and real sense.
Size of mine hot stove depends on manufacturing dimensions and craft, need undertakes detailed computation and design.
Mine heats up principle of alloy of manganese of furnace refine silicon:
On the process of smelt be heated of charging, the costly oxide of the manganese in charging and iron is in loading area by pyrolysis or CO reductive into low oxide, arrive when 1373 ~ 1473K, costly oxidation manganese gradually by sufficient and reductive into MnO, all FeO is farther reductive into Fe; MnO is stabler, can undertake with carbon only direct and reductive, because charging is medium SiO2 is taller, mnO still does not have there's still time reductive the siliceous manganese that reacts union became low melting point to it. Accordingly, the reductive reaction of MnO has in the siliceous manganese of liquid state slag actually.
The condition of siliceous manganese and melting point are:
℃ of =1250 of frit of MnO+ SiO2=MnSiO3 T
℃ of =1345 of frit of 2MnO+ SiO2=Mn2SiO4 T
As a result of the compound Mn3C that manganese and carbon can stabilize inherently, with carbon direct and reductive the carbide Mn3C that those who get is manganese. Its react type is:
MnOoSiO2+4/3C=1/3Mn3C+ SiO2+CO↑
The ferric oxide in charging compares oxidation manganese easily reductive, the iron that comes out beforehand and manganese are formed in all fuse-element (MnoFe) 3C, improved the reproducibility conditions of MnO greatly.
As the heighten of temperature, silicon also by reductive come out, its react is:
SiO2+2C= Si+2CO↑
Because silicon and manganese can compare the compound MnSi with stabler Mn3C inherently, when reductive when the Si that come out comes up against Mn3C, the carbon in Mn3C by displacement come out, volume of the carbon in causing alloy drops, its react type is:
1/3 Mn3C + Si =MnSi+1/3C
As reductive the progress of the silicon content that come out, carbonization manganese is destroyed, the carbolic content in alloy is reduced further.
From inside liquid state slag with carbon the total reaction type of alloy of silicon of reductive production manganese is:
MnO·SiO2+3C= MnSi +3CO↑
△ Gθ=3821656.6-2435.67T
The oxide of the phosphor in charging falls in inferior temperature namely by reductive, reductive reaction presses type undertakes:
△ Gθ=85100-81.32T
Its begin to react temperature is 773 ℃ , the phosphor in charging has 75% to enter about into alloy.
In the smelt process of manganese silicon alloy, to improve the reproducibility conditions of silicon, there must be enough SiO2 in charging, undertake in order to make sure smelt process lies from beginning to end below acid slag; But, if broken bits is medium SiO2 excessive, can cause cuttings pick-up difficulty again, normally the slag composition of alloy of smelt manganese silicon is: (SiO2)=34% ~ 42%
, (CaO+MgO)/ SiO2=0.6 ~ 0.8, (Mn) < 8% .
1, manganese silicon alloy is right of hearth carbon brick corrode
The density of alloy of ① manganese silicon is very big
Because the density of manganese silicon alloy is very big, and the alloy with opposite very big density to hearth of charcoal piece erode, corrode should compare many serious, the alloy with opposite very big density is slaggy the osmosis of pair of charcoal piece clearance is very big, because this manganese silicon adds up to the hearth of Qian,the hearth service life of otherer alloy wants alloy of short silicon of much ② manganese to be mixed easily carbolic brick produces the report that add charcoal
Manganese can be changed into Mn7c3, Mn3C, Mn23C6 with charcoal, amid Mn3C Zuo is manganese silicon smeltery is indispensable in-between is angry.
When alloy of ② manganese silicon produces the inferior broken bits acid-base value in making to corrode smeltery of alloy of silicon of more serious manganese to charcoal brick to slant normally acerbity basic slag is operated actually, and charcoal brick is fought slant the working capability of alkaline broken bits is stronger, the working ability that fights acid slag is poorer, because smeltery of alloy of this manganese silicon is complete the process is medium, broken bits is right of charcoal brick corrode should compare than other alloy many serious.
2, the measurement of hearth temperature and decrease lukewarm
Large and medium-sized nowadays hearth is had to temperature detects and decrease lukewarm countermeasure when mine heats up furnace to be conceived in the design, but application produces manufacturer still port of continue to use effective operation method, to the measurement of hearth temperature and the inadequacy that decrease lukewarm height to take seriously, often be hearth is spent tall, the ability when very hot sign of large board hair is red adopts hearth to be decreased effectively lukewarm, at this moment hearth already arose to cannot go against sexual deformation, decrease lukewarm countermeasure to have the generation of accident of safety of slow down hearth only, but the service life of lining will a lot of a lot of decrease.
The measurement of ① hearth temperature
The measurement of hearth temperature can bury a thermal resistance beforehand when wall of hearth build by laying bricks or stones, thermal resistance can be buried in the crucible area lower part that class of three-phase report report produces, as a result of here is spent is hearth transmits larger position, thermal resistance spends operate the deepness that section basis thermal resistance buries 1 decision-making, insert in Zuo aluminium when thermal resistance among brick and clay brick, deepness 1250? When 300mm, thermal resistance is lukewarm accuse to be among 600~800 ℃ be less than 600 ℃ hearth to be able to be stopped decrease lukewarm, of the measurable hearth that carry Zuo is spent, reduce calorific quantity to damage, promote temperature thermal resistance of the control, energy-saving; that decrease a platoon then is spent when crossing 800 ℃ high, the calorific capacity that transmits hearth large board is more, hearth large board, hearth raises labour profiled bar to be able to encounter hot deformation, then hearth shoots firebrick layer to also be met deformation fission, should promote hearth to decrease at this moment lukewarm.
Of ② hearth decrease lukewarm
Of hearth decrease Wen Ding to be heated up with coming loose with wind cold pattern or water-cooling, because water-cooling comes loose hot item investment is large and put very big safe risk uses centrifugal fan water-cooling accordingly commonner however.
Decrease according to hearth lukewarm can make hearth large board and hearth raise steel to be spent at effective , the key that keeps steel is spent, the basis condenses line fundamental is decreased according to hearth lukewarm the coagulation that can make the environmental temperature of charcoal brick is less than molten iron broken bits is spent, produce the covering layer ply that condenses in the surface layer of fireproof insulation material in that way.
3, manganese silicon mine heats up furnace to answer in designing conception a lot of advertent difficult problem
The certain and peculiar character of smeltery of manganese silicon alloy, the design conception that stipulates manganese silicon mine heats up furnace should have not at other nonferrous metal furnace or calcium carbide furnace.
Fireproof insulation material should have ① to protect practical effect amply
Detailed heat insolation should be done to calculate when the design is conceived, the that calculates large board of hearth extraction a cost is spent cannot exceed 350°C, when the design is conceived the basis that calculating statistical data is makings of boiler setting choosing and Bao Hou of wall of build by laying bricks or stones. Normally the circumstance falls specific the harm that gets character of fireproof insulation material and quality of wall of build by laying bricks or stones, calculate all computation to run quickly according to putting must deviation, essential factor of this kind of deviation should consider when the design is conceived.
Need to hearth measures in ② design conception, reduce lukewarm plan plan furnace of alloy of silicon of a lot of manganese spends Zuo as a result of hearth , move below the firebrick molten that cause and hearth:
Move below deformation, sure meeting moves to cause the deformation shift of charcoal brick layer below boiler setting, infiltration of final molten iron of Jian fruit that is to say wears a bottom. When do if not be the temperature of hearth,measuring a record to wear bottom safety accident with respect to the resolution that do not have a law arise, also nature does not have a law to differentiate is to wear of the hearth after the bottom to spend first rise, Zuo is the bottom is worn after hearth spends deformation promoting trade first. The resolution to accident reason and prevent to do not have a law to begin. Because the temperature of this hearth is measured, decreasing lukewarm design to conceive do not not matter, also cannot be versed in with strong point of because of contractible operation cost hearth of leave out ③ profiled bar needs to have enough hot compressive strength
The compressive strength of stainless steel plank subsequently the rise that spends and pelter, when spends more than 350 ℃ , 500 ℃ , 600 ℃ , the compressive strength of stainless steel plank reduces 1/3, 1/2, 1/3 severally, next exceeding is spent 15 minutes in 500 ℃ when plank of carring capacity stainless steel Zuo is met deformation cave in, the after encountering heat compressive strength that section of strong point labour should consider when accordingly the design is conceived transforms, indispensible Shi Jiahou hearth or consider adiabatic heat preservation is actual the fireproof insulation material with right result.
4, the wall of build by laying bricks or stones of hearth
In fireproof insulation material passing state falls, quality of wall of boiler setting build by laying bricks or stones is very great to harm of hearth service life, the wall of formulary intention build by laying bricks or stones that because this is built in boiler setting Chang ,must want carry out a design strictly to conceive regulation and build by laying bricks or stones of GBJ211 industry electric stove to build project project construction and construction to check and accept a standard in whole process.
All and fireproof insulation material all should ensure passing, normally manufacturer home is mixed to firebrick the character regulation of charcoal brick is taller, and incompact to shooting the igneous earth, check that seams paste to close, if the Zhou fire between each other is spent when the difference with component is very big, rift can be created after nodding furnace.
Fireproof insulation material and insulation material are magnesian qualitative raw material should avoid get damp very, the accumulation of fireproof insulation material of rainy district should have the waterproof the way to deal with a situation that prevent rain, the moisture in fireproof insulation material is too big, increase even between the that forge needs.
The build by laying bricks or stones of boiler setting is seamed is boiler setting in most the phase of instability, lining service life is in the character that build by laying bricks or stones must depend on seaming on the level, without when seaming wall of joining together build by laying bricks or stones, want on the spot beforehand build by laying bricks or stones, carry brick, wide seam place want Yan Ke to seam paste to pound dozen of treatment craft, wall of build by laying bricks or stones must maintain clean on the spot,
5, forge
The moisture content of full amount is contained in the boiler setting of new step wall, if not forge of all previous classics instantly production of feed in raw material is made be in Zuo is lukewarm enter the water steam volatilizes splash goes up can make lining deformation or fission. Another pounds dozen of thickener circumjacently to put in charcoal brick have must clearance, what forge of all previous classics can let factory of its melt, cooking produce high density to spend is overall, promote the service life of lining.
Forge must want to safeguard good charcoal brick to prevent air combustion in the process completely, in fireproof insulation material 100 ℃ fluctuate in forge whole process adiabatic heat preservation is beneficial to what water divides to volatilize, in 300? Compare among 500 ℃ carry slow lukewarm be beneficial to the knot that pounds dozen of makings anxious. In the light of instantly real operation must want the dot furnace of electric smelter to carry out graph closing gate strictly to execute.
6, the smeltery of manganese silicon alloy is operated actually
Manganese can be changed into material of chemistry of varied manganese charcoal with charcoal report, if melt down flotsam is in,condiment is short of charcoal in the process completely or partial condiment is not well-balanced the report that is aggravating manganese and charcoal brick, bring about to hearth corrode.
In operating circuit so that carry Zuo SiO2 to mirror a gender, does normally Lao acid-base value operate in 0.5? 0.7 among, but cross low acid-base value to be able to make dot of broken bits dissolve decreases, the coagulation among charcoal brick and broken bits layer line arises not easily, broken bits is right of charcoal brick corrode a line to also sink with , broken bits is right of charcoal brick corrode accentuation.
7, summary
Of raw material of wall of the build by laying bricks or stones in conception of ① hearth design choose makings is unscientific, hearth Bao Hou is insufficient wait for cause to make hearth spends litre of business easily.
② measures height to take inadequacy seriously to hearth temperature, decrease lukewarm countermeasure to make hearth spends ceaseless generation rising Zuo without hearth move below hearth deformation, cause accident of the safety that wear a bottom finally.
Fireproof insulation material closes ③ nevertheless, hearth is the brick seams character of wall is in build by laying bricks or stones to close molten iron of easy also generation to wear bottom safety accident nevertheless especially.
Moisture of fireproof insulation material crosses ④ big, carry when forge lukewarm too fast first be the cause that causes hearth rupture.
⑤ smeltery is operated actually unscientific first be the cause that causes accident of the safety that wear a bottom.