Method for improving soluble zinc rate of fuming furnace secondary zinc oxide smoke dust

Abstract

According to the method for improving the zinc soluble rate of the secondary zinc oxide smoke dust of the fuming furnace, a pure oxygen pipeline is introduced into an outlet pipe of a tertiary air fan of the fuming furnace, an automatic adjusting valve group is arranged, when the tertiary air fan of the fuming furnace is started, the pure oxygen pipeline adjusting valve group is automatically opened, and the pure oxygen pipeline adjusting valve group and tertiary air of the fuming furnace are forcibly blown into the fuming furnace together, so that the zinc soluble rate of the secondary zinc oxide smoke dust of the fuming furnace is increased. Carrying out oxidation reaction with valuable metals such as zinc volatilized by blowing in the fuming furnace to form secondary zinc oxide smoke dust; the method is convenient to operate, the zinc soluble rate of the fuming furnace secondary zinc oxide smoke dust can be effectively increased, the quality of the fuming furnace secondary zinc oxide smoke dust is improved, and the leaching production operation efficiency of the next procedure is improved.

Description

Technical Field

[0001] This invention relates to the field of pyrometallurgical furnace blowing, specifically a method for improving the soluble zinc content in zinc oxide flue dust from a pyrometallurgical furnace. Background Technology

[0002] As described in CN115574607A, a fuming furnace is a device that blows a mixture of air and pulverized coal into the high-temperature slag of a liquid Kifset furnace, causing valuable metals such as zinc in the liquid high-temperature slag to volatilize in the form of metals, oxides, or sulfides. Its process principle is as follows: the fuming process is essentially a reduction volatilization process, that is, the mixture of pulverized coal and air is blown into the liquid high-temperature slag in the fuming furnace, causing the lead and zinc oxides in the slag to be reduced into lead and zinc metal vapors. Lead oxides and lead sulfides with higher vapor pressures can also volatilize directly in compound form. The metal vapors, metal sulfides, and oxides enter the upper space of the furnace along with the flue gas, where they are re-oxidized into lead oxide and zinc oxide by specially introduced tertiary air, and then captured in a dust collection device for recovery as secondary zinc oxide dust.

[0003] When the above-mentioned fuming furnace is working, liquid Kifset furnace high-temperature slag is added through the slag feed pipe. Pulverized coal and combustion air are blown in through the primary air pulverized coal nozzle, and combustion air is mainly blown in through the secondary air nozzle for combustion assistance. At the same time, a molten pool of 1200℃~1300℃ is formed inside the fuming furnace, which reduces the lead and zinc oxides in the liquid high-temperature slag into lead and zinc metal vapors. After the metal vapors enter the upper space of the fuming furnace, they are oxidized into zinc oxide and lead oxide by the air supplemented by the tertiary air blast port. Then, they enter the waste heat boiler for cooling and collection through the flue gas outlet, and the remaining molten slag is discharged through the molten slag discharge outlet.

[0004] Due to the significant increase in zinc metal content in the high-temperature slag of the Kifset furnace, even when the amount of air supplied to the tertiary air vent of the fuming furnace reaches its maximum value, it is still insufficient to fully oxidize the lead and zinc metal vapors. As a result, the collected secondary zinc oxide dust contains elemental zinc metal, and the soluble zinc rate is mostly below 95%, which has a significant impact on the leaching production of the next process and reduces operating efficiency. Summary of the Invention

[0005] This invention develops a method to improve the soluble zinc content of zinc oxide fumes from fuming furnaces. The method involves introducing a pure oxygen pipeline into the outlet pipe of the tertiary air blower of the fuming furnace and installing an automatic regulating valve group. When the tertiary air blower is started, the pure oxygen pipeline regulating valve group automatically opens, forcibly blowing the oxygen into the furnace along with the tertiary air. This oxygen reacts with the zinc metal volatilized from the furnace during smelting to form zinc oxide fumes. This method is convenient to operate, effectively improves the soluble zinc content of zinc oxide fumes from fuming furnaces, enhances the quality of zinc oxide fumes, and improves the efficiency of leaching operations in subsequent processes.

[0006] A method for improving the soluble zinc content in zinc oxide dust from a fuming furnace, the specific method being as follows:

[0007] (1) A pure oxygen pipeline is introduced into the tertiary air blast outlet of the fuming furnace, and a regulating valve group is installed to automatically regulate and control the oxygen flow rate.

[0008] (2) When the tertiary air blower of the fuming furnace is started, the pure oxygen pipeline regulating valve group automatically opens and is forced into the fuming furnace along with the tertiary air blower to form an oxygen-rich state.

[0009] (3) When a large amount of valuable metals such as zinc volatilized from the fuming furnace reaches the upper part of the furnace, they react with the oxygen-enriched tertiary air forced into the fuming furnace to form secondary zinc oxide dust, and the solubility of secondary zinc oxide dust is above 96%.

[0010] Furthermore, the oxygen enrichment rate of the oxygen-enriched state described in step (2) is 25%.

[0011] Advantages of this invention:

[0012] 1. Due to the significant increase in zinc metal content in the high-temperature slag of our Kifset furnace, the demand for tertiary air in the fuming furnace has increased. By introducing a pure oxygen pipeline into the outlet pipe of the tertiary air fan and setting up a regulating valve group, automatic feedback regulation of oxygen flow has been achieved. It can be directly controlled in the DCS system, making the operation simple and convenient.

[0013] 2. Since the quality of secondary zinc oxide in the fuming furnace has a significant impact on the efficiency of the leaching process in the next step, when the oxygen enrichment rate of the tertiary air is autonomously controlled and dynamically monitored in real time, the soluble zinc rate of secondary zinc oxide in the fuming furnace can be guaranteed to be above 96%, which greatly reduces the impact on the production of the next step. Detailed Implementation

[0014] Example 1

[0015] A method for improving the soluble zinc content in secondary zinc oxide dust from a fuming furnace, the specific method being as follows:

[0016] (1) A pure oxygen pipeline is introduced into the tertiary air blast outlet of the fuming furnace, and a regulating valve group is installed to automatically regulate and control the oxygen flow rate.

[0017] (2) When the tertiary air blower of the fuming furnace is started, the pure oxygen pipeline regulating valve group will automatically open and be forced into the fuming furnace together with the tertiary air blower to form an oxygen-rich state with an oxygen enrichment rate of 25%.

[0018] (3) When a large amount of valuable metals such as zinc volatilized from the fuming furnace reaches the upper part of the furnace, they react with the oxygen-enriched tertiary air forced into the fuming furnace to form secondary zinc oxide dust, and the solubility of secondary zinc oxide dust is above 96%.

[0019] In our company's actual production, when using the method of the above embodiments, the solubility rate of zinc oxide dust in the fuming furnace is mostly 97-98%, and some are even around 99%.

[0020] In conclusion, 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 within the protection scope of the present invention.

Claims

1. A method for improving the soluble zinc content in zinc oxide flue dust from a fuming furnace, characterized in that: The specific method for improving the soluble zinc content in zinc oxide flue dust from the fuming furnace is as follows: (1) A pure oxygen pipeline is introduced into the tertiary air blast outlet of the fuming furnace, and a regulating valve group is installed to automatically regulate and control the oxygen flow rate. (2) When the tertiary air blower of the fuming furnace is started, the pure oxygen pipeline regulating valve group automatically opens and is forced into the fuming furnace along with the tertiary air blower to form an oxygen-rich state. (3) When a large amount of valuable metals such as zinc volatilized from the fuming furnace reaches the upper part of the furnace, they react with the oxygen-enriched tertiary air forced into the fuming furnace to form secondary zinc oxide dust, and the solubility of secondary zinc oxide dust is above 96%.

2. The method for improving the soluble zinc content in secondary zinc oxide dust from a fuming furnace according to claim 1, characterized in that: The oxygen enrichment rate in the oxygen-enriched state described in step (2) is 25%.