Method for efficiently smelting high-sulfur high-arsenic tin concentrate

Abstract

A method for efficiently smelting high-sulfur and high-arsenic tin concentrate comprises the following steps that (1) the high-sulfur and high-arsenic tin concentrate is fed into a fluidized bed roaster to be subjected to high-temperature roasting desulfurization and dearsenification, (2) roasted ore enters a natural gas rotary kiln to be subjected to deep desulfurization and dearsenification, and (3) roasted ore subjected to deep desulfurization and dearsenification enters a high-temperature dynamic molten pool reduction furnace to be reduced to produce low-arsenic crude tin to be subjected to crude tin refining. (4) smoke dust generated by the high-temperature dynamic molten pool reduction furnace is cyclically subjected to reduction smelting; and after the arsenic content of the smoke dust in the reduction furnace is larger than or equal to 0.5%, leaching and arsenic removal are conducted through dilute acid, and leaching residues return to the high-temperature smelting reduction furnace for crude tin smelting. According to the method, arsenic and sulfur in the tin concentrate are accurately removed step by step, arsenic and sulfur are opened out of the main tin smelting process, the influence of arsenic on tin refining is reduced, the tin refining arsenic slag rate and the tin smelting cost are reduced, the tin smelting recovery rate is increased, and the tin smelting recovery rate is larger than 97.2% or above.

Description

technical field [0001] The invention relates to the technical field of metal smelting, in particular to a method for efficient smelting of high-sulfur and high-arsenic tin concentrate. Background technique [0002] At present, domestic tin smelting and production enterprises mainly use rotary kilns to remove sulfur and arsenic from tin concentrates, but the rotary kiln process is only suitable for treating low arsenic and low sulfur tin concentrates (S+As≤3%) to achieve better desulfurization and desulfurization. Arsenic effect. The conventional treatment of high-sulfur and high-arsenic materials mainly adopts the boiling roasting method. However, due to the limitations of the boiling furnace process, high-temperature roasting is easy to sinter, causing the furnace air cap to block and it is difficult to control the reaction atmosphere, resulting in calcined sand containing S+As ≥ 1%. When the calcine is subjected to reduction smelting, the reduction smelting produces tin s...

AI Technical Summary

Problems solved by technology

[0002] At present, domestic tin smelting enterprises mainly use rotary kiln to remove sulfur and arsenic from tin concentrate, but the rotary kiln process is only suitable for processing low-arsenic and low-sulfur tin concentrate (S+As≤3%) to achieve better desulfurization and desulfurization arsenic effect

Conventional processing of high-sulfur and high-arsenic materials mainly adopts fluidized roasting method, but due to the limitation of fluidized fluidized furnace process operation, high-temperature roasting is easy to sinter, causing the furnace air cap to be blocked and difficult to control the reaction atmosphere, resulting in calcined sand containing S+As≥1%

When the calcined sand is reduced and smelted, the sulfur content in the calcined sand is too high, resulting in the production of tin sulfide by reduction smelting, the dust rate of tin reduction smelting is high, and the direct yield of tin reduction smelting is low

However, the arsenic in the calcined sand is partially reduced into the crude tin, and is returned to the crude tin in the form of arsenic-aluminum slag for reduction smelting when the crude tin is refined to remove arsenic, resulting in a decrease in the direct yield of crude tin refining, and the arsenic-aluminum slag easily generates arsine when it meets water. Toxic gas must be protected from water and moisture, environmentally friendly storage, and high potential safety hazards; the arsenic in the calcined sand is affected by the reduction and volatilization of the high-temperature molten pool. The cost of smelting increases. Due to the high-temperature and easy-to-reduce volatile characteristics of arsenic, the arsenic in tin concentrate is continuously accumulated in the reduction furnace and tin refining slag, which is difficult to remove, further increasing the cost of tin smelting and reducing the recovery rate of tin smelting Wait