JPS59153847A - Smelting method of zinc by blowing - Google Patents

Abstract

PURPOSE:To continue a steady operation in a condenser while decreasing the generation of dross and improving a winning rate of zinc by floating lumped or granular coke at all times on the matte surface in a smelting furnace and sealing the slag surface. CONSTITUTION:Sintered zinc ore is changed together with a reducing agent and air enriched with oxygen into a smelting furnace and is smelted. The formed zinc vapor is condensed and captured with a condenser provided integrally with the smelting furnace. Coke powder and/or pulverized coal, etc. are used as a reducing agent in the smelting stage and the top surface of the slag phase formed in the smelting chamber of the smelting furnace is covered with said coke powder or pulverized coal. Then, a substantial injection depth is assured and even if the sintered zinc ore and reducing agent floats temporarily on the matte surface, these powder materials are captured by the coke layer and the scattering thereof to the condenser is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is characterized in that zinc sintered ore is blown into a smelting furnace together with a reducing agent and oxygen-enriched gas to melt it, and the produced zinc sinter is efficiently processed by using a condenser installed integrally with the smelting furnace. This invention relates to improvements in iron manufacturing methods that allow good condensation and recovery, maintain the combustion heat of exhaust gas at a high calorie level, and reuse it.

In general, a needle furnace is operated using a top-blown lance method. That is, the zinc calcined ore and the powdered reducing agent are slowly blown in at high speed together with oxygen-enriched air. In the process, the powdered coke powder and/or powdered coal reacts with oxygen in the blown gas and zinc oxide in the slag to form CO or COP.

Some of the burnt ore remains solid and is reduced by CO.

Large lbs of zinc vapor is collected in the fins and dissolved in the flax. If unreacted zinc sinter and powdered reducing agent float to the surface, they will scatter to the condenser integrated with the smelting furnace. These unreacted substances themselves reduce the yield of zinc.

Inside the capacitor, an unmarried core of zinc is formed.

It becomes dross and significantly changes the rate of zinc condensation in the condenser. In order to prevent the elongated lead burnt ore and the powdered reducing agent from floating to the unreacted surface of the slag, it is necessary to inject these raw materials at high speed into the 1F to maintain a sufficient injection depth and complete the above reaction in the slag. Do four things.

The blowing speed, lance height, etc. that satisfy this requirement are set for each smelting furnace.
During operation, due to fluctuations in the slag composition, slag level, etc., a sufficient injection depth could not be obtained, resulting in a sudden increase in connotesser loss.

The purpose of the invention is to reduce the generation of dross.

The aim is to improve the zinc recovery rate and continue smooth operations at the condenser.

To this end, the present inventors have developed a conventional smelting furnace slag ui.
A lump of coke is constantly floating on top of the i.

A method of operating 7-hole Kamamen has been presented. With this method, even if 111 lead burnt ore and powdered reducing agent temporarily float to the surface, these powdered wJ will be collected as coke and will be prevented from scattering into the container. I found out that it can be done.

The thicker the coke layer on the fin surface, the stronger the sealing effect, but it also prevents injection into the slag of the blowing field.
Because of this, there is a limit to the thickness, 50~・250F
7: The level was appropriate. In addition, in order to ensure the coke temperature in the furnace, the size of the lump coke must be UIO~・50.
K. degree is desirable.

− of carbon in lump coke? VB Zn in U slag
OI! : Contact, next reaction ZnO+ C-+ Zn(1)+ CQ
As a result of , , , Zn vapor and cm residue are generated.

It also reacts with CO2 gas produced by the reaction of raw H blown into the slag, generating CO gas.

C-+-CQ2→2CO...■ These reactions consume the lump coke in the furnace, so
Lump coke is replenished intermittently so that the lump coke is present on the slag surface in the -T groove. Also, ■■
Since both of the reactions are endothermic reactions, the amount of oxygen blown in from the lance is added to the powdered reducing agent blown in from the lance, and the amount of oxygen is set to be large in order to reduce the heat of the entire smelting furnace. do.

Furthermore, to reduce the generation of dross, we added flux and changed the composition of the slag to FeO/S.
t021~3.5. By setting the FeO/CaO in the range of 1.5 to 10 and lowering the viscosity of the slag, the injection depth into the slag was ensured and the method of suppressing the scattering of unreacted substances was made possible.

If 113 min is high during sintering, a slag with relatively low viscosity is formed, but if the iron content is insufficient, it has been found that replenishment with dust powder etc. is effective. If used in combination with a coating method, the effectiveness will further increase.

Example 1 A chrome magne noa brick lined cylindrical furnace 2 having an external diameter of 2 m and a length of 5.9 m was used as a smelting furnace. This furnace held 20 tons of molten slag eN, and each slag was pulverized to about -200 mtsuyu 80% pass. I use zinc sintered ore and coke powder with low lead content!
It was blown in from the top with 9 qi from the lance. In addition, lump coke was intermittently introduced from the unit at the top of the smelting furnace. Approximately 1 ton of lump coke was charged before the start of operation, and thereafter 125 kg of lump coke was replenished every 30 minutes, so that about 2 (1!) lump coke layer was always formed on the slag surface.

Shows the composition of burnt ore and coke breeze.

a) Charged burning ore composition (wt%) mouth) coke powder set 5'x, (wt 'lb) c) slag composition table IVIc Other tea juice and papermaking viscosity are shown.

In addition, the bundling in the case where there is no lump coke as the relative softness H is also 7.
Catty, zu. As is clear from Table 1, by adding 1 coke 7+), the contentor loss is approximately 2
73V decreased, and the recovery rate of other ships was 8596 (comparison I'l
+) to 91%. In addition, rotor trouble in the content area decreased, and operations continued to perform well in January.
1: It's here.

Example 2 Using a molten needle furnace with 11 and 11, 100% of iron powder and limestone powder (-100%) were mixed with burnt ore to reduce FeO/5i02'' in the slag. 2.5.F'eO
/CaO" 4. The 'rA' operation was carried out so that Q was obtained, and the a! operation was continued. The charged sintered ore and coke breeze compositions were the same as in Example 1. The slag composition is shown below.

In this case as well, the capacitor loss is reduced, indicating that the slag composition has an effect.

Comparative Example Same as Example 1 except that no lump coke was used.
Zinc was recovered in F. 2-1-1 Nihonbashi Muromachi, Chuo-ku, Tokyo

Claims (2)

[Claims] (1) Using a furnace with a continuous smelting chamber and condensation chamber, a slag phase with a composition close to the p' e / S t 02 ratio in zinc burnt ore and a crude lead phase below the slag phase are prepared in advance in the melting needle chamber. ¥ consisting of? r
A molten bath is formed, and the zinc sintered ore and a reducing agent are blown into the molten bath together with oxygen-enriched nitrogen gas so as to be catalytically mixed to obtain a product gas consisting of Zn vapor, etc., while the valuable area in the zinc sintered ore is The reduced molten iron step in which Zn is collected in the crude lead and the gas produced in the melting step are introduced into the spray of molten lead or molten zinc in the condensation chamber, and the Zn vapor in the produced gas is In the zinc needle making method, which consists of a condensation step in which molten lead or molten zinc is condensed and collected, coke powder and/or pulverized coal is used as a reducing agent in the smelting step, and the coke powder or pulverized coal is used to reduce the slag phase. A zinc needle manufacturing method using blow smelting, which is characterized by the top surface being recessed. (2) Regarding FeO,5i02 and CaO of the slag, the composition is FeO/SiO2''1~3.5,
The zinc needle making method according to claim 1, characterized in that the Fed/Cab" is 1.5 to 10.