Lub lim tiam dhau los, tus nqi ntawm cov khoom siv raw hauv tsev ntawm feem ntau hom tseem poob qis, thiab qhov poob qis dua. Hauv qhov kev thov rau cov khoom tiav lawm tsis tau tso tawm zoo, kev ua lag luam yuav txo qhov xwm txheej, kev tswj hwm kev tsim khoom hlau txo qis ntau ntxiv, ua rau muaj kev nyuaj siab rau kev ua lag luam raw. Tus nqi hlau ore tseem poob qis heev lub lim tiam dhau los; Tus nqi coke metallurgy tag nrho poob qis; Tus nqi coking thee ruaj khov rau lub caij nplooj zeeg; Tus nqi ntawm cov khoom tseem ceeb Ferroalloy poob qis. Thaum lub sijhawm no, kev hloov pauv tus nqi ntawm cov khoom tseem ceeb yog raws li nram no:

Cov nqi rau cov hlau uas xa tuaj rau txawv teb chaws poob qis heev