Zinc dross feem ntau yog cov khoom ntawm cov tshuaj tiv thaiv ntawm zinc thiab hlau. Nws lub ntsiab tivthaiv yog cov hlau-zinc alloy txheej theem tsim los ntawm kev sib xyaw ntawm zinc thiab hlau. Yog li ntawd, zinc dross feem ntau muaj li 3 mus rau 6% hlau thiab txog 94 mus rau 97% zinc. Hauv qee cov txheej txheem kub-dip galvanizing, txhuas yog ntxiv los tiv thaiv lub lauj kaub galvanizing. Hauv cov xwm txheej zoo li no, zinc dross tuaj yeem muaj 1.5 mus rau 2% txhuas (tsis yog hais txog cov hmoov txhuas sib xyaw ua ke). Feem ntau, nyob rau hauv kub-dip galvanizing ntawm steel kav, txhuas yog txhob txwm ntxiv kom tau ib tug kaj galvanized txheej. Yog li ntawd, zinc dross kuj tseem muaj qee qhov nyiaj ntawm txhuas.
Cov kav hlau tsuas tuaj yeem muab tso rau hauv molten zinc tom qab pretreatment. Thaum lub sij hawm pretreatment, yog hais tias ntxuav tsis huv, hlau ntsev tej zaum yuav adhered rau saum npoo ntawm cov yeeb nkab steel yuav tsum galvanized. Thaum kub kub galvanizing, cov khoom siv hlau xws li steel kav, steel galvanizing pots, thiab cov yeeb nkab galvanizing tshuab yog yaj los ntawm molten zinc. Kev sib koom ua ke ntawm cov hlau thiab zinc atoms ua rau tsim cov hlau-zinc alloy txheej. Ntawm lawv, qee lub sij hawm (krystals) tuaj yeem tshem tawm ntawm lub substrate thiab dab dej mus rau hauv qab ntawm lub lauj kaub galvanizing, accumulating rau zinc dross. Feem ntau, nyob rau hauv "qhuav txoj kev" kub-dip galvanizing ntawm steel kav, tus nqi ntawm zinc dross nyiaj li ntawm 10 mus rau 20% ntawm tag nrho cov zinc noj.
Thaum lub sij hawm tsim ntawm zinc dross, cov tshuaj tiv thaiv yog raws li nram no:
(1) Cov tshuaj tiv thaiv los ntawm cov ntsev hlau
FeCl₂ + 8Zn → ZnCl₂ + FeZn
FeCl₂ + 14Zn → ZnCl₂ + FeZn₁₂
(2) Cov tshuaj tiv thaiv los ntawm cov hlau
Fe₈C + 21Zn → 3FeZn₇ + CFe₈
C + 39Zn → 3Fe₈Zn₁₈ + C (Ceeb toom: Cov tshuaj formula rau carbon nyob rau hauv lub thib ob cov tshuaj tiv thaiv yuav tsum tau muab sau tseg raws li nws tsis hloov nyob rau hauv cov ntsiab lus no, tab sis nws yog ib qho tseem ceeb kom paub tias carbon yog ib tug reactant.)
