Cov khoom siv raw thiab kev tsim cov graphite electrodes

Cov khoom siv raw rau kev tsim cov graphite electrodes yog roj av coke, koob coke thiab thee tar.
Petroleum coke yog ib yam khoom uas combustible tau los ntawm coking petroleum residue thiab roj av asphalt. Nws yog xim dub thiab ntxeem tau, nrog cov pa roj carbon ua lub ntsiab lus tseem ceeb thiab cov hmoov tshauv tsawg heev, feem ntau qis dua 0.5%. Petroleum coke belongs rau qeb ntawm yooj yim graphitized carbon. Petroleum coke yog dav siv nyob rau hauv cov tshuaj thiab metallurgical industries thiab yog lub ntsiab raw khoom rau kev tsim khoom graphite khoom thiab carbon cov khoom rau electrolytic txhuas.
Petroleum coke tuaj yeem muab faib ua cov coke nyoos thiab calcined coke raws li kev kho cua sov. Cov qub yog roj av coke tau los ntawm kev ncua coking, muaj ntau cov teeb meem tsis hloov pauv thiab muaj zog txhua yam. Calcined coke yog tau los ntawm calcining raw coke. Feem ntau cov refineries hauv Suav teb tsuas yog tsim cov coke nyoos, thiab kev ua haujlwm calcination feem ntau yog ua los ntawm cov nroj tsuag carbon.
Petroleum coke tuaj yeem muab faib ua peb hom raws li cov ntsiab lus sulfur: high-sulfur coke (sulfur ntsiab lus saum toj no 1.5%), nruab nrab-sulfur coke (sulfur ntsiab lus 0.5%-1.5%) , thiab low-sulfur coke (sulfur ntsiab lus hauv qab no 0.5%). Graphite electrodes thiab lwm yam khoom siv graphite feem ntau yog tsim los siv cov coke uas tsis muaj sulfur. Koob coke yog ib qho zoo coke nrog pom tseeb fibrous kev ntxhib los mos, tsis tshua muaj thermal expansion coefficient, thiab yooj yim graphitization. Thaum cov coke blocks tawg, nws tuaj yeem muab faib ua cov kab ntev thiab nyias nyias (qhov piv txwv feem ntau yog siab dua 1.75) raws li kev ntxhib los mos. Cov qauv anisotropic fibrous tuaj yeem pom nyob rau hauv lub tshuab ntsuas polarizing, yog li nws hu ua koob coke. Lub anisotropy ntawm lub cev thiab txhua yam khoom ntawm koob coke yog pom tseeb heev. Nws muaj cov hluav taws xob zoo thiab thermal conductivity thaum uas tig mus rau qhov ntev axis ntawm cov khoom, thiab muaj cov thermal expansion coefficient tsawg. Thaum lub sij hawm extrusion molding, ntev axis ntawm feem ntau hais yog teem nyob rau hauv lub extrusion kev taw qhia. Yog li, koob coke yog cov khoom siv tseem ceeb rau kev tsim hluav taws xob siab lossis ultra-high-power graphite electrodes. Cov graphite electrodes uas ua tau muaj qhov tsis muaj zog, me me thermal expansion coefficient thiab zoo thermal shock kuj. Koob coke tau muab faib ua roj-raws li koob coke ua nrog roj av residue li raw khoom thiab thee-raws li koob coke ua nrog refined thee tar li raw khoom. Coal tar yog ib qho ntawm cov khoom tseem ceeb ntawm kev sib sib zog nqus ntawm cov thee tar. Nws yog kev sib xyaw ntawm ntau yam hydrocarbons. Nws yog ib tug dub, high-viscosity semi-khoom los yog khoom nyob rau hauv chav tsev kub. Nws tsis muaj qhov ntsuas kub ruaj khov. Nws softens thiab ces melts tom qab cua sov. Qhov ceev yog 1.25-1.35g/cm3. Raws li cov ntsiab lus softening, nws muab faib ua peb hom: low-temperature, medium-temperature thiab high-temperature asphalt. Cov txiaj ntsig ntawm qhov nruab nrab kub asphalt yog 54-56% ntawm cov thee tar. Qhov sib xyaw ntawm thee tar yog qhov nyuaj heev, uas muaj feem xyuam rau cov khoom ntawm thee tar thiab cov ntsiab lus ntawm heteroatoms, thiab tseem cuam tshuam los ntawm cov txheej txheem coking thiab coal tar ua tej yam kev mob. Muaj ntau cov cim qhia txog cov khoom ntawm thee tar, xws li asphalt softening point, toluene insoluble matter (TI), quinoline insoluble matter (QI), coking value and rheological properties of the coal tar. Coal tar yog siv los ua ib qho kev khi thiab impregnant hauv kev lag luam carbon, thiab nws cov kev ua tau zoo muaj kev cuam tshuam zoo rau cov txheej txheem tsim khoom thiab cov khoom zoo ntawm cov khoom siv carbon. Binder asphalt feem ntau siv nruab nrab-kub los yog nruab nrab-kub hloov asphalt nrog nruab nrab softening point, siab coking nqi thiab siab resin. Lub impregnant yuav tsum siv nruab nrab-kub asphalt uas tsis muaj softening point, qis QI thiab zoo rheological zog.