A method for measuring the thickness of slag layer in a Kifset furnace

Abstract

The present invention develops a method for measuring the thickness of the slag layer of the Kifsate furnace melt. The method obtains the thickness values ​​of the lead layer and the slag layer by operating the lifting and lowering of each electrode and monitoring the current value. This method breaks the drawbacks of the existing technology for measuring the slag layer thickness, innovates a new detection method, fills the domestic technical gap, and achieves the purpose of scientifically determining the thickness of the slag layer and lead layer in the electric heating zone of the Kifsate furnace.

Description

Technical Field

[0001] The invention relates to the field of kifset furnace smelting in pyrometallurgy, and in particular to a method for measuring the thickness of a slag layer in a kifset furnace melt. Background Art

[0002] The main structure of the Kifuset furnace is mainly divided into four parts: a reaction tower 2, a sedimentation tank 6, an electric heating zone 4 and an ascending flue 1, which are arranged on a unified fixed hearth. The reaction tower 2 and the electric heating zone 4 are separated by a water-cooled partition wall 3. There is also an electric heating zone flue 5 on the top of the electric heating zone 4. Three electrodes are set on the top of the electric heating zone 4: C phase electrode 9, B phase electrode 10, and A phase electrode 11.

[0003] The Kifsett process for direct lead smelting is a flash smelting process where oxidation, desulfurization, and reduction are performed continuously within a single unit, directly producing crude lead. The charge undergoes a sulfide oxidation reaction within the reaction tower, melting the charge particles and producing a melt composed of metal oxides, metallic lead droplets, and other components. As the melt passes through the coke filter layer on the surface of the sedimentation tank, most of the lead oxide is reduced to metallic lead and settles to the bottom. The melt then flows through the lower opening of the water-cooled partition wall into the electric heating zone, where the slag and lead further settle and separate, forming a lead layer 7 at the bottom and a slag layer 8 at the top. These are then discharged through the slag discharge port at the end of the electric heating zone and the lead discharge port at the side, respectively. The crude lead from the Kifsett furnace enters the continuous copper removal furnace in liquid form for impurity removal and refining. The slag from the Kifsett furnace enters the fuming furnace in liquid form to recover the lead and zinc metals from the slag.

[0004] When the Kifset furnace is operating, the thickness of the slag layer directly affects the smoothness and safety of production: when the slag layer is thin, the lead liquid level is high, which will hinder the melt in the reaction tower from entering the electric heating zone, causing the melt level in the reaction tower to remain high, posing a safety risk of melt overflow; when the slag layer is thick, the lead liquid level is low, making it difficult to discharge crude lead, and there is a safety risk of large amounts of slag being carried out during the crude lead discharge process. Therefore, during the continuous operation of the Kifset furnace, it is necessary to dynamically monitor the slag layer thickness in the electric heating zone of the Kifset furnace in real time to effectively ensure the safe and stable operation of the Kifset furnace.

[0005] In the existing technology, a steel rod is inserted into the Kifsate furnace sedimentation tank using the gauge hole on the top of the Kifsate furnace reaction tower, and then the steel rod is pulled out. The slag and lead attachments on the steel rod are observed to determine the dividing line, thereby inferring the thickness of the slag layer. This method is mostly used in copper flash smelting. Since the melting point of lead is very low, when the steel rod is pulled out of the Kifsate furnace sedimentation tank, the lead is melted when passing through the slag layer, resulting in the inability to distinguish the dividing line and the inability to infer the thickness of the slag layer. Instead, the only way is to roughly estimate whether the discharge of crude lead is appropriate based on the input and output of the furnace charge. Summary of the Invention

[0006] The present invention develops a method for measuring the thickness of the slag layer of the Kifsate furnace melt. The method obtains the thickness values ​​of the lead layer and the slag layer by operating the lifting and lowering of each electrode and monitoring the current value. This method breaks the drawbacks of the existing technology for measuring the slag layer thickness, innovates a new detection method, fills the domestic technical gap, and achieves the purpose of scientifically determining the thickness of the slag layer and lead layer in the electric heating zone of the Kifsate furnace.

[0007] A method for measuring the thickness of a slag layer in a Kifset furnace melt is as follows:

[0008] (1) Keep the melt level in the electric heating zone in a stable state. At this time, the three electrodes are located in the slag layer. Then, use a measuring rod to vertically insert it into the slag layer from the observation hole in the electric heating zone. Make the upper edge of the measuring rod close to the lower edge of the observation hole. The total height h of the melt in the electric heating zone is obtained. The calculation method of h is the elevation of the lower edge of the observation hole minus the length of the measuring rod that does not touch the melt.

[0009] (2) The two electrodes remain stationary, and the other electrode is lifted. When its current value just drops to zero, it is considered to have reached the slag layer surface. At this time, the relative height value of this electrode is h1;

[0010] (3) Lower the electrode by a height value d. If the current value is much lower than the rated current, it is considered to be in the slag layer. At this time, the relative height value of the electrode is h2;

[0011] (4) According to steps (2) to (3), repeat the above operations with the other two electrodes respectively, so that all three electrodes are lowered to the same height value d and are on the same horizontal line in the slag layer;

[0012] (5) Continue to lower the electrode until its current value approaches the rated current, which is considered to be just reaching the surface of the lead layer. At this time, the relative height value of the electrode is h3; at this time, the slag layer thickness measured by this electrode is: h1-h3;

[0013] (6) Lift the electrode to the relative height h2 so that the three electrodes are on the same horizontal line in the slag layer;

[0014] (7) According to steps (5) to (6), measure the thickness of the slag layer using two other electrodes respectively;

[0015] (8) After the above three electrodes are measured, the relative height values ​​of the three electrodes are adjusted to the state before measurement. At this time, the three electrodes serve as heating devices in the electric heating zone.

[0016] Furthermore, the height value d is 400mm-600mm.

[0017] Furthermore, the ruler rod is a 90° ruler rod.

[0018] Furthermore, the thickness of the lead layer is h-(h1-h3).

[0019] Advantages of the present invention:

[0020] 1. The three electrodes, C-phase electrode, B-phase electrode, and A-phase electrode, are immersed in the slag layer as heating devices in the electric heating zone. By operating the lifting and lowering of each electrode and monitoring the current value, the thickness values ​​of the lead layer and the slag layer are obtained. This method breaks the drawbacks of the existing technology for slag layer thickness measurement, innovates a new detection method, fills the domestic technical gap, and achieves the purpose of scientifically determining the thickness of the slag layer and lead layer in the electric heating zone of the Kifset furnace;

[0021] 2. The above measurement method can be used to dynamically grasp the thickness of the slag layer and lead layer in the electric heating zone of the Kifsate furnace in real time, which is helpful to guide the operator to adjust the process control parameters and control the amount of lead and slag melt discharged, effectively ensuring the safe and stable operation of the Kifsate furnace;

[0022] 3. The thickness values ​​of the lead layer and slag layer measured by the three electrodes are not averaged, but listed separately as process guidance parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of step (1) of the present invention;

[0024] Figure 2 This is a schematic diagram of step (2) of the present invention;

[0025] Figure 3 This is a schematic diagram of step (3) of the present invention;

[0026] Figure 4 This is a schematic diagram of step (4) of the present invention;

[0027] Figure 5 This is a schematic diagram of step (5) of the present invention;

[0028] Figure 6 This is a schematic diagram of step (8) of the present invention;

[0029] In the figure: 1- ascending flue, 2- reaction tower, 3- water-cooling partition wall, 4- electric heating zone, 5- electric heating zone flue, 6- sedimentation tank, 7- lead layer, 8- slag layer, 9- C phase electrode, 10- B phase electrode, 11- A phase electrode. DETAILED DESCRIPTION

[0030] Example 1

[0031] A method for measuring the thickness of a slag layer in a Kifset furnace melt is as follows:

[0032] (1) Figure 1As shown, the melt level in the electric heating zone 4 is kept stable. At this time, the three electrodes are located in the slag layer 8. Then, a 90° measuring rod is vertically inserted into the slag layer 8 from the observation hole of the electric heating zone 4. The upper edge of the 90° measuring rod is closely attached to the lower edge of the observation hole. The total height h of the melt in the electric heating zone 4 is obtained. The calculation method of h is the elevation of the lower edge of the observation hole minus the length of the 90° measuring rod that does not contact the melt.

[0033] (2) Figure 2 As shown, the A-phase electrode 11 and the B-phase electrode 10 remain stationary, and the C-phase electrode 9 is lifted. When its current value just drops to zero, it is considered that it has reached the surface of the slag layer 8. At this time, the relative height value of the C-phase electrode 9 is h1;

[0034] (3) Figure 3 As shown, the C-phase electrode 9 is lowered by a height value d. If its current value is much lower than the rated current, it is considered to be in the slag layer 8. At this time, the relative height value of the C-phase electrode 9 is h2;

[0035] (4) Figure 4 As shown, according to steps (2) to (3), repeat the above operations with the other two electrodes respectively, so that the three electrodes are all lowered to the same height value d and are on the same horizontal line in the slag layer;

[0036] (5) Figure 5 As shown, the C-phase electrode 9 is further lowered until its current value approaches the rated current, which is considered to be just reaching the surface of the lead layer 7. At this time, the relative height value of the C-phase electrode 9 is h3; at this time, the slag layer thickness measured by the C-phase electrode 9 is: h1-h3;

[0037] (6) Lift the C-phase electrode 9 to the relative height h2, so that the three electrodes are on the same horizontal line in the slag layer 8;

[0038] (7) According to steps (5) to (6), the thickness of the slag layer 8 is measured using two other electrodes;

[0039] (8) After the above three electrodes are measured, the relative height values ​​of the three electrodes are adjusted to the state before measurement. At this time, the three electrodes serve as heating devices in the electric heating zone.

[0040] The thickness of the lead layer is h-(h1-h3).

[0041] In actual production, since the slag layer thickness in the electric heating zone of our company's Kifusite furnace is generally >500mm, the above height value d is generally fixed at 500mm.

[0042] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for measuring the thickness of a slag layer in a Kifset furnace, characterized in that: The measuring method is as follows: (1) Keep the melt level in the electric heating zone in a stable state. At this time, the three electrodes are located in the slag layer. Then, use a measuring rod to vertically insert it into the slag layer from the observation hole in the electric heating zone. Make the upper edge of the measuring rod close to the lower edge of the observation hole. The total height h of the melt in the electric heating zone is obtained. The calculation method of h is the elevation of the lower edge of the observation hole minus the length of the measuring rod that does not touch the melt. (2) The two electrodes remain stationary, and the other electrode is lifted. When its current value just drops to zero, it is considered to have reached the slag layer surface. At this time, the relative height value of this electrode is h1; (3) Lower the electrode by a height value d. If the current value is much lower than the rated current, it is considered to be in the slag layer. At this time, the relative height value of the electrode is h2; (4) According to steps (2) to (3), repeat the above operations with the other two electrodes respectively, so that all three electrodes are lowered to the same height value d and are on the same horizontal line in the slag layer; (5) Continue to lower the electrode until its current value approaches the rated current, which is considered to be just reaching the surface of the lead layer. At this time, the relative height value of the electrode is h3; at this time, the slag layer thickness measured by this electrode is: h1-h3; (6) Lift the electrode to the relative height h2 so that the three electrodes are on the same horizontal line in the slag layer; (7) According to steps (5) to (6), measure the thickness of the slag layer using two other electrodes respectively; (8) After the above three electrodes are measured, the relative height values ​​of the three electrodes are adjusted to the state before measurement. At this time, the three electrodes serve as heating devices in the electric heating zone.

2. The method for measuring the thickness of the slag layer of a Kifset furnace according to claim 1, characterized in that: The height value d is 400mm-600mm.

3. The method for measuring the thickness of the slag layer of a Kifset furnace according to claim 1, wherein: The ruler-checking rod is a 90° ruler-checking rod.

4. The method for measuring the thickness of the slag layer in a Kifset furnace according to claim 1, wherein: The thickness of the lead layer is h-(h1-h3).

Images