Low Temperature Flotation of a Low-grade Phosphate Rock in Yichang by Modified Fatty Acids

In order to develop the low−grade colloidal phosphate ore resources with low magnesium and high sesquioxide in a mine in Yichang of Hubei Province, cotton oil fatty acid soap was used as raw material and compounded with polyoxyethylene ether nonionic surfactant to obtain a good selective anionic collector MON−135, which was used to conduct a pilot study of low temperature direct and reverse flotation. The experimental results showed that at a flotation pulp temperature of 14 ℃ and a grinding fineness of −0.074 mm 93.7%, a process was adopted involving direct flotation with one roughing and one cleaning and one scavenging followed by one roughing and one scavenging in reverse flotation, the dosages of sodium carbonate, water glass and MON−135 for direct flotation roughing were 7.0 kg/t, 3.0 kg/t and 1.4 kg/t, respectively; the dosage of MON−135 for positive flotation sweeping was 0.5 kg/t; the dosages of sulfuric acid and collector LAA−T for reverse flotation roughing were 9.0 kg/t and 0.9 kg/t, respectively; and the dosage of sulfuric acid for sweeping was 2.5 kg/t. the phosphate concentrate P₂O₅ grade of 32.61% and recovery of 92.67% were obtained in the closed circuit test. The results show that the use of low temperature collector can effectively flotation collophane ore at a lower flotation temperature, and can obtain a better beneficiation index.