The energy crisis is one of the major challenges confronting the cement industry today. Although non-renewable energy sources are becoming scarce, the presence of significant quantities of oil shale indicates its continued use as an energy source in the cement industry. However, significant environmental impacts may occur as a result of the large amount of oil shale ash (OSA). As a result, the researchers are investigating alternative methods for recycling and reusing the OSA in a variety of applications. The purpose of this work was to use OSA as a green substitute component in cement production due to its high calcium oxide (CaO) content, which is the major component of cement clinkers. The chemical composition of OSA and Clinker samples were determined using X-ray fluorescence (XRF) and X-ray diffraction (XRD). OSA and clinker samples were combined in various ratios and then ground in a ball mill to obtain the desired grain size. The new blended products were prepared and tested at Lafarge factory's laboratories. The results indicated that by adding 10% of OSA to the clinker, the mixed product performed better than the reference sample. Additionally, using this percentage of OSA results in a 45% reduction in the power consumption of the grinding process compared to the reference sample.

The quest for environmentally friendly reagents in froth flotation processes has gained significant importance for minimizing ecological impacts. This research investigates the utilization of chitosan polymer as a green depressant for silicate minerals in the direct flotation of phosphate minerals. To understand the behaviour of the flotation feed, zeta potential measurements were conducted to assess the electrical properties of mineral surfaces in the presence and absence of chitosan polymer. Furthermore, the effects of chitosan dosage, pulp pH, and flotation time on the flotation recoveries and concentrate grade of phosphates were studied. Comparative analyses were performed by comparing the flotation recoveries of phosphate minerals achieved using chitosan polymer with those obtained when employing a commercial silicate dispersant, sodium silicate. The findings revealed that at a dosage of 300g/ton, the recovery of phosphate minerals reached approximately 70% when using chitosan polymer, whereas the recovery was only around 40% with the same dosage of sodium silicate dispersant. These outcomes demonstrate the potential of chitosan as an effective and sustainable silicate depressant in the phosphate flotation process under specific conditions.