Na-eji
Ụlọ ọrụ ihe owuwu ụlọ: eji na-emepụta ciment, iko na ihe ndị ọzọ na-ewu ụlọ,anthracite calcinednwere ike inye okpomọkụ zuru oke maka usoro ịgba ọkụ ọkụ dị elu iji hụ na ịdị mma na arụmọrụ nke ihe ụlọ. N'otu oge ahụ, obere ntụ ọdịnaya ya na-enyekwa aka belata mmetọ na gburugburu ebe obibi.