System for treating tin smelting intermediate materials and method for treating same

A method for treating tin smelting intermediate materials by using a system,

• wherein the system comprises:
• a fuming furnace, an electric settling furnace, a lean slag water quenching pool, a matte ladle, a pulverized coal injection system, and a flue gas treatment system;
• wherein the fuming furnace is connected with the electric settling furnace, the pulverized coal injection system, and the flue gas treatment system,
• wherein the electric settling furnace is connected with the lean slag water quenching pool and the matte ladle,
• wherein the method comprises:
• (a) before feeding hot tin slag into the fuming furnace, maintaining a temperature of flue gas in the fuming furnace at 600-800° C.;
• (b) lifting a hot tin slag transfer ladle through a hook scale system, introducing the hot tin slag in the hot tin slag transfer ladle into the fuming furnace through a hot tin slag feeding chute disposed on the fuming furnace;
• wherein before being placed on the slag feeding chute, a weight of the hot tin slag is measured by the hook scale system;
• (c) after the hot tin slag is introduced into the fuming furnace through the hot tin slag feeding chute, turning on a belt feeding system, uniformly adding a tin-copper mineral material and lump coal into the fuming furnace within 60-120 min through the belt feeding system;
• (d) after the tin-copper mineral material and the lump coal are completely added into the fuming furnace, turning off the belt feeding system, and increasing an amount of pulverized coal blowing into the fuming furnace by the pulverized coal injection system;
• heating and melting the hot tin slag, the tin-copper mineral material and the lump coal in the fuming furnace;
• controlling a Fe/SiO2 ratio of a first molten pool to 1.0-1.4, and keeping the temperature of the flue gas at 1050-1150° C. for 30-60 min to completely melt the hot tin slag, the tin-copper mineral material and the lump coal in the first molten pool in the fuming furnace to obtain high-temperature melt;
• wherein the first molten pool is formed in the fuming furnace and is formed by melting first slag containing Fe and SiO2;
• (e) inserting a sample rod into the high-temperature melt in the first molten pool to take a first melt sample for a first elemental analysis to obtain a Sn content and a Cu content;
• adding a vulcanizing agent, through the belt feeding system, into the fuming furnace to volatilize melt tin in the high-temperature melt within 90-120 min according to a S/(Sn+Cu) molar ratio of 1:3 and a surplus coefficient of 1.2-1.3;
• taking a second melt sample for a second elemental analysis;
• when a tin content in the second melt sample is not greater than 0.3 wt. %, determining that the melt tin in the fuming furnace has volatilized;
• and when the tin content in the second melt sample is greater than 0.3 wt. %, adding an extra vulcanizing agent into the fuming furnace until the tin content in a final melt sample is not greater than 0.3 wt. %;
• wherein an addition amount of the vulcanizing agent is determined in accordance with the S/(Sn+Cu) molar ratio of 1:3, and surplus coefficient is 1.2-1.3;
• (f) before discharging the high-temperature melt in the fuming furnace into the electric settling furnace, melting second slag with Fe/SiO2 ratio of 0.9-1.3 in the electric settling furnace to form a second molten pool, and keeping a temperature of the second molten pool in the electric settling furnace at 1200-1230° C.;
• discharging the high-temperature melt with the tin content not greater than 0.3 wt. % into the electric settling furnace through a high-temperature melt chute disposed on the electric settling furnace, obtaining matte by keeping the electric settling furnace continuously heated until a copper content of upper lean slag therein is not greater than 0.7 wt. %, opening a matte port disposed on a low part of the electric settling furnace, discharging the matte in the electric settling furnace to the matte ladle through a matte discharge chute communicated with the matte port, and immediately sealing the matte port when the matte is completely discharged and the upper lean slag is tended to flow out of the matte port;
• discharging the upper lean slag in the electric settling furnace into the lean slag water quenching pool through a lean slag discharge chute at an upper part of the electric settling furnace for water quenching, removing water in lean slag after water quenching to obtain dried lean slag;
• wherein during a discharging process of the upper lean slag, the sample rod is configured to detect a depth of the upper lean slag in the electric settling furnace, when the depth of the upper lean slag is 300-500 mm, sealing an outlet communicated with the lean slag discharge chute and using remaining upper lean slag for keeping a temperature in the electric settling furnace so as to receive next high-temperature melt discharged by the fuming furnace.