Drywall Recycling Market: Manufacture of Portland CementGypsum is an ingredient in the manufacture of portland cement, added to control the setting time of the concrete. Gypsum is added to the cement clinker from the kiln and the mixture is processed to a fine powder. The typical gypsum content of portland cement ranges from 5 to 10%. Mined gypsum rock is often used by the cement kilns, and the different physical form of processed drywall may necessitate adjustment of the facility's materials handling system. The purity of gypsum in the wallboard is a major concern. Paper should be removed, and care should be taken during the collection of the wallboard to minimize the amount of impurities such as soil that are introduced. |