Chert Deposit Used in Cement Production as a Quartz-Sand Alternative in the Iraqi Kurdistan Region: An Assessment Study

Silica-sand is one of the main additives in cement production. Cement plants in the Iraqi Kurdistan Region had been using silica sand which is 98% quartz that was quarried from the Iraqi Western Desert. However, during the last decade, it was not possible to supply these cement plants with material from this location; therefore, the silica sand was imported from Iran. Recently, radiolarian chert of the Qulqula Group was quarried from the Sharbazhar Quarry in Kurdistan and used in some cement plants in the Kurdistan Region. This research was performed to study the specifications of the chert which is interbedded with claystone of the Qulqula Group that can be used as an alternative to silica-sand from other regions outside of Kurdistan. Five samples were collected from the Sharbazhar Quarry and subjected to XRF testing. The acquired results were encouraging; therefore, 20 additional samples were collected from the quarry, but also from other outcrops of the Qulqula Group along the road towards Sulaimaniyah city. The collected samples were subjected to XRF testing and the results showed that the weighted average of the SiO2 in the quarried chert–claystone deposit is 83.71%., when the plants used claystone:chert ratio is 3:2; as it is used with mix-raw material in some cement plants in the Bazian district. This deficiency in the weighted average of the SiO2 is overcome by adding more chert from the chert–claystone deposit to the raw-mix