Iron(II) sulfate is added to cement during discharge from cement works storage silos

摘要

In a cement preparation process, iron(II) sulfate particles are added, as reducing agent for eczema-causing water-soluble chromate, to the cement being discharged from large intermediate storage silos in the cement works. Preparation of a cement, which contains eczema-causing water-soluble chromate and which is mixed with 0.01-1 wt.% dry iron(II) sulfate particles for chemical reduction of this chromate(VI), in which the ground cement is stored in large silos in the cement works and withdrawn for transport in silo trucks or for packaging in sacks, the novelty is that the dry iron(II) sulfate particles are added to the cement on withdrawal from the large silos. Preferred Features: When sacks are being filled, an automatically weighed quantity of iron(II) sulfate is introduced continuously into the cement flowing into the sacks or in portions into the sacks.