Determine the composition of the sulfuric acid slag resulting from the roasting of pyrite
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Please provide the composition of the sulfuric acid slag resulting from the roasting of pyrite. Thank you
The minerals used are different, resulting in varying compositions of the slag; however, it is primarily a mixture of iron oxide and ferric oxide, along with acid-insoluble substances.
The sulfation roasting of pyrite generally takes place at temperatures above 600°C. The main components of the sulfuric acid slag are iron oxide and ferric oxide; if the raw material contains impurities such as lead, arsenic, and zinc, then lead sulfate, arsenic trioxide, and zinc sulfate may also be present. If copper is present, copper sulfate will be formed
The products obtained from the roasting of pyrite are: t/d Au Ag Pb Fe S Al2O3 CaO MgO SiO2 CO2 O2 N2 H2O; other substances include ferric tetraoxide, ferrous trioxide, sulfates, and the sulfate content is related to other impurities present in pyrite.
Name, Materials Added, Materials Produced: Gold Concentrate, Slurry Moisture, Dry Air, Air Moisture, Total; Roasted Ore, Flue Gas, Total – in t/d: 191, 16.61, 615.1, 6.76, 829.47, 136.60, 692.51, 829.11. Au (g/t): 1.67, 2.34 kg/d; 0.319, 0.319. Ag (g/t): 23.83, 33.34 kg/d; 4.55, 4.55. Pb %: 0.34, 0.48 t/d; 0.649, 0.649. Fe %: 42.1, 58.86 t/d; 80.41, 80.41. S %: 45.11, 0.5 t/d; 86.16, 0.71. Al2O3 %: 0.76, 1.06 t/d; 1.45, 1.45. CaO %: 0.75, 1.05 t/d; 1.43, 1.43. MgO %: 0.72, 1.01 t/d; 1.37, 1.37. SiO2 %: 8.32, 11.63 t/d; 15.89, 15.89. CO2 %: 1.4 t/d, 2.67. O2 %: 23.3, 24.72 t/d; 143.33, 33.77. N2 %: 76.7 t/d, 471.77. H2O %: 100, 100 t/d; 16.61, 6.76. Others %: 0.50, 0.7 t/d; 1.00, 0.96
Is there any residual pyrite that hasn’t been burned away?
Different roasting methods produce varying types of slag, including oxidative roasting, magnetic roasting, sulfation roasting, and arsenic removal roasting. Here, we will give an example of the common oxidative roasting. In the case of an oxygen excess, the furnace temperature is higher, and the slag consists mainly of iron oxide trioxide with some iron oxide tetraoxide; at this time, the temperature distribution is roughly as follows: furnace bed temperature: 800–850, furnace crucible temperature: 900–950