CN1153837C

CN1153837C - Process for smelting zinc

Info

Publication number: CN1153837C
Application number: CNB001099809A
Authority: CN
Inventors: 赖成章
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-08-09
Filing date: 2000-08-09
Publication date: 2004-06-16
Anticipated expiration: 2020-08-09
Also published as: CN1300862A

Abstract

The present invention relates to a fire smelting method and a matched smelting furnace for smelting refined zinc and lead bullion once, which overcomes a plurality of defects in the background art. The present invention has the technical scheme that a smelting furnace is composed of an electric furnace in the upper position and a blast furnace in the lower position; the smelting furnace also comprises a reversed water condenser, a zinc accumulating tank, a tank-bottom temperature adjusting electric furnace, a small condenser, etc., wherein the blast furnace is used for reducing metal through smelting; the electric furnace is used for heating carbon in the furnace into high-temperature carbon; carbon dioxide in furnace gas is completely decomposed into carbon monoxide which is transported into the condenser for cooling into liquid zinc and liquid cadmium; the liquid zinc and liquid cadmium flow into the zinc accumulating tank, and the cadmium is vaporized into the small water condenser after temperature raising; the cadmium is collected by cooling, and the refined zinc is smelted.

Description

Zinc smelting method

The invention relates to a smelting method for smelting zinc, lead and cadmium by a pyrogenic process, in particular to a smelting method which can directly and once smelt refined zinc by roasted ore and can smelt non-ferrous metals such as crude lead, cadmium and the like.

At present, the known zinc smeltingtechnology has a history for hundreds of years, and the zinc smelting method is divided into a pyrometallurgical zinc smelting method and a wet zincification zinc smelting method. The pyrometallurgical zinc smelting is divided into the following steps according to different main equipment: flat tank zinc smelting, vertical tank zinc smelting, blast furnace zinc smelting, electric furnace zinc smelting and the like. The technology of the blast furnace zinc smelting method is advanced according to the type of the existing pyrometallurgical zinc smelting in the world, the smelting speed is high, the yield is high, and the technical data provided by the institute of mining and metallurgy in the south of China, the institute of nonferrous metallurgy in Changsha, the institute of nonferrous metallurgy in Beijing, the institute of information standard of department of metallurgical industry and the like are used as the basis. Issued by the metallurgical industry publishers as follows:

the blast furnace zinc smelting method is actually a blast furnace smelting lead-zinc sinter, and obtains zinc and lead at the same time. It is a new achievement of the pyrometallurgical zinc smelting technology. Since the trial production in the Argwos plant of the UK in 1950, such blast furnaces have now appeared in many countries and regions. The area of the largest furnace tuyere area reaches 28 square meters, and the annual zinc production reaches 12 ten thousand tons.

The blast furnace zinc smelting mainly comprises three processes of sintering roasting, sinter block reduction smelting and zinc vapor condensation.

1. The sintering roasting mainly converts zinc sulfide and lead sulfide into zinc oxide and lead oxide, and sinters the zinc oxide and lead sulfide into blocks to adapt to blast furnace smelting. Sintering was carried out on a strand sinter machine (as with a lead smelting sinter machine).

2. The connection of the equipment for smelting zinc by the blast furnace is shown in the attached figure 4. The blast furnace used is similar to a conventional lead smelting blast furnace. But the top of the furnace is sealed and is therefore commonly referred to as a closed blast furnace. To prevent air leakage from the top of the furnace (which would reoxidize the zinc vapour), the charging device uses a double bell charger similar to that used in iron making blast furnaces.

As in the case of zinc vertical retort, the charge materials to be charged must be preheated, and the sintered cake and coke preheated to above 700 ℃ are charged into the furnace and then reduced in the high temperature zone of the furnace to form zinc oxide and lead oxide. The lead has high boiling point (1525 ℃), the reduced lead is converted into liquid lead, the reduced zinc is mixed with furnace gas in the form of steam, and the mixture enters a condenser from the upper part of the furnace to be condensed into liquid metal zinc. Liquid lead is deposited at the bottom of the furnace (hearth) and slag is also accumulated to the bottom of the furnace, both the lead bullion and the slag being tapped periodically. In order to obtain a sufficiently high temperature in the furnace, the blown air is preheated to above 700 ℃.

3. Condensation of zinc vapour furnace gases exiting the blast furnace generally contain not high (only about 6%) zinc vapour, up to more than 20% carbon monoxide and more than 10% carbon dioxide. Due to the high concentration of carbon dioxide, there is a risk that zinc vapour is oxidised to zinc oxide by carbon dioxide. In order to avoid such a bad situation, the following measures must be taken; (1) the temperature of the discharged gas is kept above 1000 ℃. Therefore, preheating air is also introduced into the upper part of the furnace, so that part of carbon monoxide in the furnace gas is combusted to improve the temperature of the furnace gas; (2) liquid lead is used to condense the zinc vapour. The condenser is called as a lead rain condenser, and the lead liquid is raised into fine drops (called as lead rain) by a rotor, so that zinc vapor is rapidly condensed into liquid zinc and dissolved in the liquid lead. Discharging the lead liquid containing zinc from the condenser, cooling to 450 deg.C, separating out part of zinc dissolved in lead, and separating into two layers due to different specific gravity, the upper layer is zinc, discharging and casting into zinc ingot, and the lower layer is lead, pumping into the condenser with lead pump, and reusing. The adoption of the lead rain condenser is a key factor for promoting the expanded use of the blast furnace for zinc smelting.

The main advantages of the closed blast furnace smelting method are that it can process lead-zinc sulfide ore or oxide ore which is difficult to be selected, and at the same time, it can produce lead and zinc, and its yield is large, heat efficiency is high and unit metal yield investment is low. But things are always split in two. The blast furnace has the following problems: the operating conditions are strict; sintering blocks, and coke must be preheated; the lead content in the sintered cake cannot be too high and the zinc produced must be further refined.

17.2m commonly used abroad²The relevant data for the zinc smelting blast furnace are as follows:

area of furnace tuyere zone	17.2m²	Annual production of zinc	4-7.7 ten thousand tons
area of furnace tuyere zone	17.2m²	Annual production of zinc	4-7.7 ten thousand tons	Annual lead production	0.8-3.6 ten thousand tons	Consuming coke every day	190 tons of 120-
Agglomerate composition (%)	26-46 zinc, 17 lead- 22 copper 0.2-2	Recovery (%)	94 percent of zinc, 97 percent of lead, 82 percent of copper	Annual lead production	0.8-3.6 ten thousand tons	Consuming coke every day	190 tons of 120-
Agglomerate composition (%)	26-46 zinc, 17 lead- 22 copper 0.2-2	Recovery (%)		The crude zinc contains zinc	98-99.6％

The invention aims to design a method for smelting zinc, which is used for overcoming the problems in the prior pyrometallurgical zinc smelting method and technology: the air is preheated to above 700 before entering the furnace for smelting. And liquid lead rain is also used as condensate, and the smelted zinc is also crude zinc and is sent to a refinery for refining. The zinc smelting method for forming zinc makes great innovation in the zinc smelting technology and the process flow by a pyrogenic process: the oxygen-enriched gas is fed into furnace at normal temp. for smelting, and does not use liquid lead as condensate, but uses water as indirect condensate, and in the field of zinc smelting technology by pyrogenic process a new smelting method and a new smelting technology for smelting refined zinc and cadmium from ore at one time are developed.

The technical scheme of the invention is as follows:

1. smelting and reducing metal by using a blast furnace: the oxygen-enriched gas blown into the furnace chamber by the blast furnace burns and oxidizes the carbon in the raw material to release high heat quantity: ( 、 ) The metal in the ore in the furnace chamber is forced to be heated to 1300-1500 ℃, carbon monoxide formed by high-temperature carbon and carbon in the furnace chamber and oxidized metal generate reduction reaction at high temperature to generate liquid metal lead and copper: ( 、 ) Etc. gaseous metals formed after reduction, e.g. zinc, cadmium: ( 、 ) And liquid metal is discharged from a metal outlet at the bottom of the furnace, and slag is discharged from a slag pool outlet. The gaseous metal is combined with the discharged gas dust and is pumped into the electric furnace.

2. Decomposing carbon dioxide in furnace by electric furnace including arc furnace, frequency electric furnace, and electric heating furnace, wherein the frequency electric furnace is divided into frequency power furnace and high frequency furnace, the heating element of the electric heating furnace is divided into silicon carbide heating element electric furnace and resistance wire electric furnace, and the electric furnacesThe coke oven is a device for converting electric energy into heat energy, the coke added into the electric oven utilizes the heat energy converted from the electric energy to heat and keep the temperature of the coke between 1000-1200 ℃, and carbon dioxide gas in the furnace gas passes through a red hot coke layer to be fully decomposed into carbon monoxide (CO) ) And the carbon dioxide in the furnace gas is lower than 0.5 percent. Gaseous substances and dust in the electric furnace are pumped into a water condenser which is arranged at the rear of a zinc flue opening and connected with the upper part of the electric furnace by an exhaust fan.

3. The water of the inverted water condenser is used as indirect condensate to cool gaseous zinc and cadmium in the furnace gas into liquid zinc and cadmium, and the liquid zinc and cadmium flow into the zinc accumulation pool.

4. The zinc accumulation pool is used for accumulating zinc and heating liquid zinc and cadmium in the pool to 800-plus 830 ℃ by utilizing a temperature-regulating electric furnace below the pool to ensure that the cadmium in the zinc accumulation pool is fully evaporated and is pumped into a small water condenser together with dust in furnace gas.

5. The small condenser uses water as indirect condensate to cool cadmium vapor into liquid cadmium, which flows into the cadmium collecting tank to be discharged periodically for collection. The dust and carbon monoxide in the furnace gas are pumped into a dust collector.

6. The dust collector is specially used for collecting dust, the dust is collected after being deposited, and other gases are pumped into the exhaust fan by the exhaust fan.

7. The exhaust fan has the function of sucking out furnace gas and dust in the electric furnace by using electric energy, and the furnace gas is treated by the equipment and then is pumped into the exhaust fan and then is sent to a gas washing field through a smoke exhaust pipe and an electric smoke exhaust valve.

8. And the gas washing field is used for washing the discharged furnace gas and collecting and utilizing the carbon monoxide.

The zinc smelting furnace comprises a blast furnace, an electric arc furnace, a zinc smoke channel port, an inverted water condenser, a zinc accumulation pool temperature-adjusting electric furnace, a cadmium accumulation pool, a small water condenser, a smoke dust processor, an exhaust fan, a smoke exhaust pipe and a smoke exhaust pipe valve, wherein the electric arc furnace is arranged on a blast drum and is communicated with a furnace chamber of the blast furnace through a furnace outlet air hole at the bottom of the electric arc furnace; one end of the smoke zinc passage opening is connected with the furnace shell of the electric arc furnace in a positioning way, and the other end of the smoke zinc passage opening is communicated with an inverted water condenser arranged below the smoke zinc passage opening; the zinc accumulation pool is arranged below the inverted water condenser and is connected with the inverted water condenser in a positioning way; the temperature-adjusting electric furnace of the zinc accumulation pool is arranged at the bottom of the zinc accumulation pool; the small water condenser is connected with the zinc accumulation pool through a flue pipe; the cadmium accumulation pool is arranged below the small water condenser; the smoke dust processor is communicated with the upper end of the small water condenser; the exhaust fan is connected with the top of the smoke dust processor; the smoke exhaust pipe is connected with the gas outlet of the outlet, and the gas discharged from the furnace is sent to the gas washing field through the smoke exhaust pipe valve.

The invention relates to a zinc smelting furnace, wherein the electric arc furnace is provided with a furnace shell and a furnace cover which are made of steel plates and are connected in a positioning way, a charging hopper, a hopper cover, a hopper valve, a carbon hopper, a cover and a valve are arranged on the furnace cover, a high-temperature thermometer is arranged in the center of the furnace cover, three electrode holes are arranged on the furnace cover, graphite electrodes are communicated with the bottom of the electric arc furnace through the electrode holes, a closed asbestos rope is arranged at the contact part of the graphite electrodes and the furnace cover holes, three electrode plates are arranged on each graphite electrode and are used for contacting the electrodes, cables are arranged on the electrode plates and are connected with an electric furnace transformer, the electrode plates are also provided with electrode water jackets and are connected with a water pool by water inlet pipes, water outlet pipes and a water pool, the electric furnace transformer is connected with a high-voltage control screen, the high-voltage control screen is connected with a power supply, the electric furnace is also connected and controlled by a cable with an oil press, a blower, an exhaust fan, an electric air outlet valve, a water outlet valve and a smoke exhaust pipe valve, the oil press is contacted with an electrode steel sleeve to control the lifting of a graphite electrode, a refractory layer built by refractory bricks is arranged inside the electric furnace cover, a carbon brick clapboard is arranged in the electric furnace, a material warehouse is arranged between the carbon brick clapboard and an electric furnace shell, a discharge port is arranged below the material warehouse, a furnace bottom built by short-circuit carbon bricks is arranged below the material warehouse, an air hole of a middle furnace is communicated with the blast furnace cavity and is communicated with a smoke zinc passage port which is made of a steel plate at the middle upper part of the furnace shell and welded outside the furnace shell.

The invention relates to a zinc smelting furnace, wherein, the furnace chamber of a blast furnace is communicated with the furnace outlet air hole of an electric arc furnace, a firebrick layer is arranged outside the blast furnace chamber, a blast furnace shell made of steel plates is arranged outside the blast furnace chamber, and is connected with an electric arc furnace shell, a hot air layer outside the blast furnace shell is made of steel plates and welded and is connected with the electric arc furnace in a positioning way, three air inlets are arranged above the hot air layer, a high temperature thermometer which is directly communicated with the blast furnace chamber is arranged at the middle upper part of the blast furnace, three blowers, air inlet and outlet pipes which are matched with the blowers, an electric air outlet pipe valve, a slag pool, three slag outlets and a copper-silver outlet are arranged at the lower part of the blast furnace according to the arc length of 120 degrees, the lower part of the slag pool is provided with a lead pool and three lead outlets, a furnace bottom built by refractory bricks is arranged below the lead pool, a furnace bottom shell made of steel plates is arranged outside the furnace bottom, and four steel furnace legs arranged on the foundation are arranged below the furnace bottom shell.

The zinc smelting furnace has three zinc fume passage ports, which are welded and formed with steel plates and connected to the arc furnace casing in locating mode, inside refractory brick layer and connected to the inverted water condenser, which is welded and sealed with steel plates and steel pipes and has electrically operated valves for water inlet pipe, water outlet pipe and water outlet pipe.

The invention relates to a zinc smelting furnace, wherein, three zinc accumulation tanks are welded by heat-resistant steel, each zinc accumulation tank is divided into two tanks, a heat-insulating layer is arranged outside each zinc accumulation tank, a thermometer is also arranged in each zinc accumulation tank, and a zinc outlet and a lead and zinc outlet with different heights are respectively arranged in each tank.

The invention relates to a zinc smelting furnace, wherein a small water condenser is formed by welding steel plates and steel pipes and is provided with a water inlet pipe and a water outlet pipe, and a separating tank is made of the steel plates.

The invention relates to a zinc smelting furnace, wherein a smoke dust processor is made into a cylinder shape by rolling a steel plate, a clapboard layer is arranged in the smoke dust processor, a dust outlet is arranged below the smoke dust processor, and a small amount of zinc oxide can be collected.

The functions are as follows: the blast furnace functions are: oxygen blown into the furnace combusts with carbon in the raw materials to perform oxidation reaction to generate high temperature, andthe temperature of ores and the like is forced to rise to 1300-1400 ℃. Reducing the oxidized metal in the ore to metal using carbon monoxide produced by carbon and carbon in the feedstock at elevated temperatures; high boiling point metal, such as lead and copper, flows into the furnace bottom in liquid state and is discharged periodically. The gas with boiling point lower than the reduction temperature flows into the electric furnace together with the furnace gas, such as zinc and cadmium.

The electric arc furnace has the main functions: the carbon of the graphite electrode and the carbon added into the furnace are discharged with the carbon in the graphite carbon brick under the action of an electric field to form high-temperature carbon, and the high-temperature carbon and the carbon dioxide in the furnace gas are decomposed and reacted to form carbon monoxide, so that the content of the carbon dioxide in the furnace gas is reduced to below 1 percent when the carbon dioxide is discharged from the electric arc furnace. The function of the zinc flue opening is to connect the electric arc furnace with the inverted water condenser and to convey the discharged gas into the condenser. Function of the inverted water condenser: the flowing water is used as the condensate to indirectly cool the zinc vapor into liquid zinc which flows into the zinc accumulation pool.

The main functions of the zinc accumulation tank are as follows: the liquid zinc flowing into the pool is heated and kept at 800-830 ℃ for refining by using a temperature-adjusting electric furnace below the pool bottom, so that cadmium vapor is fully evaporated.

The small water condenser has the main functions as follows: cooling the gaseous cadmium into liquid cadmium, and flowing back to the cadmium accumulation pool to be discharged at regular time and collected.

The dust collector has the main functions: deposit dust in the furnace gas, reduce pollution, and collect and recycle a little zinc oxide for smelting again.

The exhaust fan, the smoke exhaust pipe and the smoke exhaust pipe valve have the main functions: controlling the gas discharging amount of the closed zinc smelting furnace, and collecting and conveying carbon monoxide to a gas washing field.

The working principle of the zinc-forming smelting method is as follows: roasting ore in raw material, proportionally charging it with carbon in electric arc furnace, then feeding it into blast furnace bosh, and making it combust with oxygen and carbon blown into furnace by blast furnace to make oxidation reaction ( ) Releasing a great deal of heat energy, so that the temperature in the bosh of the blast furnace is as high as 1500-1600 ℃, the ore, oxidized metal and the like in the raw materials are forced to rise to 1400-1500 ℃, and carbon dioxide is decomposed into carbon monoxide in the hot carbon layer (C: (C) (C)) ). At this time, ZnO and P in the ore_bO、CuO、C_dO, etc. with carbon at high temperaturesThe carbon monoxide undergoes a reduction reaction ( )( ) … …, etc. The energy required is provided by carbon. Lead, copper, silver and the like with boiling points higher than the reduction temperature are in liquid state, flow into the furnace bottom under the action of gravity and are discharged periodically, zinc with boiling points lower than the reduction temperature and the zinc with boiling points lower than the reduction temperature are in gas state (the boiling points are 918 ℃ and 768.3 ℃ respectively), and flow into the electric arc furnace through a furnace outlet. The graphite electrode, carbonin the raw materials and graphite bricks discharge arc in vector under the action of an electric field and generate extremely high temperature (2000-3000 ℃). At this time, the carbon dioxide discharged from the furnace and the high-temperature carbon are decomposed, and (C) is ) This is an endothermic reaction, with heat energy being provided by powerful electrical energy. Therefore, the carbon dioxide content of the furnace gas discharged from the electric arc furnace is lower than 1 percent, so that the discharged zinc vapor is ensured not to be oxidized again in the condensation process. The mixed furnace gas is pumped to an inverted type for condensationThe device is cooled to liquid zinc, and then the liquid zinc flows into a zinc accumulation pool for refining, the electric furnace at the bottom of the pool is heated and kept at 00-830 ℃, and steam is fully evaporated to the accumulation pool and collected, so that the process is simplified, and the purpose of refining refined zinc in the pyrometallurgical zinc refining technology is achieved.

The actual operation technology and the process flow of the zinc smelting of the zinc-forming smelting method furnace are as follows: from the electric arc furnace, the electrode hole (phi 420) of the furnace cover is added with wood through the electric arc furnace to be fired, after the fire is larger, a certain amount of coke is added, the blower 30 is started, a small amount of air is blown in and the air quantity is gradually increased, after the flame of the coke is larger, the furnace is preheated to a certain degree, the coke is continuously added into the furnace, after 1/3 of the blast furnace chamber is arranged, the oil press 18 is started, three graphite electrodes 4 are placed into the electric arc furnace, and then raw materials are continuously added into the furnace through the hopper 9: roasted ore is crushed into 30-50 specification and coke is crushed into 60-80 specification, and the mixture of the raw materials is charged into a hopper 9 according to the ratio of 5: 4 and then is charged into a blast furnace. The other two blowers 30 are started, and the amount of air is gradually increased. And simultaneously the exhaust fan 48 is started to exhaust the flue gas outwards, and the full charge can be known from the hopper 9 after a period of time. Then, a predetermined amount (40 or less) of coke is added to the hopper 51. Reflecting the continuous rise of the temperature in the blast furnace cavity from the high temperature thermometer 47 at the upper part of the blast furnace, when the temperature rises to 1000 ℃, starting an electric arc furnace switch on the operation console 14, starting the arc discharge of the electrode 4 of the electric arc furnace, gradually increasing the blast volume of the blast furnace, simultaneously relatively increasing the blast volume of the blast furnace until the temperature is 1500 ℃ displayed on the high temperature thermometer 47 of the blast furnace, keeping the blast volume, relatively increasing the arc discharge of the electrode 4 in the electric arc furnace until the temperature is 1100-1200 ℃ displayed on the high temperature thermometer 47 of the electric arc furnace, and keeping the arc discharge volume. At this time, the zinc smelting furnace enters a normal operation state, and zinc and lead are produced after a period of time.

During the continuous operation, the following method is adopted: (if the ore after the raw material roasting is powder, 20% of clay, 20% of carbon powder, 1% of grass and 5% of water are stirred and then are beaten into pellets of phi 60 by a briquette machine, the pellets are sintered in a sintering furnace to be red to 700 ℃ and then enter the furnace for smelting), the raw material is put into a hopper 9, then a hopper cover 10 is covered, a feeding valve 11 is opened, the raw material enters a material warehouse20 of an electric arc furnace, and the next material is added after the hopper valve 11 is closed, so that the raw material can be sealed with the outside. According to the charging procedure and method, the coke added into the carbon hopper is sintered to about 700 ℃ by the sintering furnace and is added into the furnace, and the carbon consumed in the process of decomposing carbon dioxide is supplemented to reduce the loss of the graphite carbon brick. The raw material storage 20 has nine discharge ports 22, and the discharge ports 22 are kept at a certain height with the blast furnace chamber, so that the raw materials are reduced and settled downwards in the smelting process. The raw material in the silo 20 is continuously fed into the furnace under gravity. The electric arc furnace generates high temperature during operation, the raw materials can be automatically heated in the material warehouse 20, and the raw materials enter the blast furnace after being heated in the electric arc furnace for the first time. Oxygen blown into the blast furnace chamber by the blower 30 is combusted with coke in the furnace to perform an oxidation reaction: ( And ) A large amount of heat energy is released. The temperature in the blast furnace B is as high as 1500-1600 ℃. The temperature of the ore can be raised continuously to 1400-1500 ℃ under the condition of forced heating.Carbon dioxide is decomposed into carbon monoxide again when it passes through the red hot carbon layer ( ) The zinc oxide and lead oxide in the ore can be quickly reduced into the original metal zinc and lead by carbon monoxide and carbon in the blast furnace belly. ( )、( )、( )、( ) At this time, the zinc metal is quickly in the form of zinc vapor and flies upward of the furnace. (since the boiling temperature of zinc is 918 ℃) metallic lead is liquid lead and flows by gravity into the lead bath 27 at the bottom of the furnace, but with very little lead volatilised as vapour to the top of the furnace. In the operation process of the closed zinc smelting furnace, air is fed into a blower 30, oxygen enriched with oxygen content of 45-80% produced by a magnetic oxygen generator in the patent technology is input into an air inlet 8, then enters a hot air layer 7 of the furnace, is heated by self and then is blown into the blast furnace, so that the furnace temperature is improved, the carbon consumption is reduced, the nitrogen content in the air is reduced, the heat energy loss in the furnace is reduced in the smelting process, and the electrodes of an electric arc furnace discharge arcs at the gas outlet of the blast furnace. The graphite electrode 4 in the electric arc furnace and the graphite carbon brick ring 6 forming short circuit can generate electric arc under the action of electric field, the electric arc releases high temperature of more than 2000-3000 ℃, at this time, the carbon in the graphite electrode, the carbon added into the furnace and the carbon in the graphite carbon brick can generate decomposition reaction with carbon dioxide gas under high temperature ( ). Therefore, the content of carbon dioxide in the furnace gas discharged from the upper part of the electric furnace is less than 1 percent. This ensures that the zinc vapour is not oxidised during the condensation process. Under the action of forced exhaust fan 48, the zinc, cadmium and lead vapour in the furnace gas discharged from the upper portion of electric arc furnace A, and other gases and dust are continuously fed into zinc flue 23, and cooled by inverted condenser 33 formed from water jacket and others. The inverted water condenser controls the water yield of the condenser through a valve 52 of a water outlet pipe to reduce the temperature of the discharged gas to be 790-810 ℃, and zinc and lead are containedThe vapor and the like are cooled to liquid zinc, and lead flows into the zinc accumulation tank 37 to be refined. The bottom tempering furnace 41 raises the liquid zinc to (800 ℃ -830 ℃ is monitored by the thermometer 38). And held. The cadmium vapor is then fully evaporated into a small water condenser 44, cooled to liquid cadmium, poured into a cadmium tank 43, periodically discharged and collected. The working principle of the zinc accumulation tanks 37 which can be used alternately is that only one tank accumulates zinc, the other tank is replaced after being filled with 4/5 liquid zinc, and after a period of sedimentation, when the temperature is reduced to about 450 ℃, the liquid zinc and lead are discharged. The zinc outlet 39 of the zinc accumulation pool 37 and the lead and zinc outlet 40 have a certain height difference, so that the refined zinc liquid is discharged from the high holes by utilizing the difference of specific gravity of zinc and lead. (the zinc content is 99.9% -99.99%) and casting into refined zinc ingot to obtain the product. Lead is discharged from the low hole and a small amount of zinc is returned to the furnace and smelted again. Collected by the fume processor 46 and a small amount of zinc oxide 50, etc. is returned to the furnace for re-smelting. Copper and silver are discharged from a metal outlet 1. Lead in the furnace bottom lead pool 27 is discharged periodically and cast into a lead bullion. The slag is discharged periodically from the slag hole 26 of the slag bath 25 and is converted into fine slag by water-milling and sent to a cement plant.

The control principle of the zinc-forming smelting furnace is as follows: the temperature heating of the arc furnace section is controlled by the control console 14 to control the voltage and the elevation of the electrodes to achieve the optimum temperature (1100-1200 c above the arc furnace) which ensures sufficient carbon dioxide decomposition to carbon monoxide. Temperature control of the blast furnace section by controlling the blower

Drawings

FIG. 1 is a longitudinal sectional view of a closed zinc smelting furnace. FIG. 1 is a drawing of the abstract of the specification.

FIG. 2 is a longitudinal sectional view of an electric arc furnace A of a type C furnace above the furnace lid.

FIG. 3 is a cross-sectional view A-A of the arc furnace A in the C-type furnace below the cover, and a longitudinal-sectional view of the arc furnace A in the C-type furnace below the cover and a blast furnace B.

FIG. 4 is a data diagram of a D-document of an old type closed blast furnace.

1. Copper and silver outlet 3 26, slag outlet 3 41, zinc-accumulating pool temperature-adjusting electric furnace 6 disc

2. Firebrick layer 27, lead pool 1 and 42, zinc pool heat preservation layer and zinc pool periphery

3. 3 electrode steel sleeves 28, 3 lead outlets 43 and 3 cadmium accumulation tanks

4. 3 graphite electrodes 29, 4 furnace feet 44 and 3 small water condensers

5. 30 parts of asbestos rope sealing parts, 20KW 3 blowers 45 and 3 parts of safe flue openings

6. 1 ring 31 at the bottom of the annular furnace carbon brick layer A, 3 air inlet pipes 46 of the fan and 3 sleeves of the smoke processor

7. Hot air layer 32, 3 fan air outlet pipes 47 and 2 high-temperature thermometers

8.3 air inlets 33, 3 inverted water condensers 48 and 10KW 3 exhaust fans

9. 3 charging hoppers 34, a plurality of water inlet pipes 49 and 3 smoke exhaust pipes

10. 3 hopper covers 35, a plurality of water outlet pipes 50 and zinc oxide

11.

Hopper valve

3, 36, steel plate 51, carbon hopper, cover and valve 3 sleeve

12. 1800KVA 1 electric furnace transformer 37, 6 zinc accumulation tanks 52, outlet pipe electric valves 3

13. 1 surface 38 of the high-pressure control panel, 6 thermometers and 53 electric air outlet pipe valves

14. Control the operation table 1 surface 39, zinc outlets 6 and 54, smoke exhaust pipe valves 3

15. 1 pool of 40, 6 lead and zinc outlets of 55 and a plurality of steel pipes with multiple diameters

16. Electrode water jacket 3 sets

17. 9 closed zinc smelting furnaces with electrode plates C

18. 2.8KW 3 electric arc furnaces of the oil press are A blast furnaces and B old type closed blast furnaces and D

19. Multiple cables

20. Layout of D zinc-smelting equipment of old type blast furnace in 1 circle of round electric furnace in stockhouse, figure 4

21. Carbon brick partition plate circular electric furnace 1 ring

22. 9 discharge ports, 1 double-bell feeder, 2 hot air main pipe and 3 forehearth

23. Smoke zinc passage port 3-4-rotor 5-condenser 6-lead pump

24. Blast furnace chamber 7-lead circular chute 8-to gas scrubbing field

25. The ratio of the blast air quantity blown into the blast furnace to the coke in the raw materials is controlled by 1 slag pool with the number of 30 slag pools and an air outlet pipe valve, so as to ensure that the temperature in the blast furnace bosh is 1500-1600 ℃, and thus, the zinc oxide and the lead oxide can be fully reduced into metallic zinc and metallic lead. Forced draft system is controlled by controlling the exhaust of the exhaust blower 48 and exhaust valve 54 to optimize the carbon monoxide content above the arc furnace and the optimal amount of zinc vapor in the inverted condenser 33. The water output of the inverted water condenser 33 is controlled to ensure adequate cooling of the zinc vapor to liquid zinc. The temperature of the temperature-adjusting electric furnace 41 is controlled to ensure that the cadmium vapor in the zinc accumulating tank 37 is fully evaporated to the small condenser 44, cooled into liquid cadmium, poured into the cadmium accumulating tank 43 and discharged periodically.

Can be built into a scientific principle of a zinc smelting furnace:

the electric arc furnace is organically combined with a closed zinc smelting furnace under an upper blast furnace, and the furnace gas discharged from the blast furnace is reducing flame with the temperature of about 1000 ℃ in the smelting process, and is contacted with graphite carbon bricks at air holes when flowing into the air inlet of the electric arc furnace, because the graphite carbon bricks are very high-temperature resistant and are not easy to decompose in the reducing flame atmosphere. The coke is taken out of the furnace and flows to the coke as the main component, and carbon dioxide in the discharged gas is quickly decomposed into carbon monoxide when the coke layer is hot red, because the coke which is hot red is porous, the contact area is increased. And then, when the graphite electrode is in arc discharge, a plurality of high-temperature free carbon atoms are formed, and carbon dioxide can be decomposed, so that the content of the carbon dioxide in the furnace gas is almost zero. Since the zinc oxide is reduced to gaseous zinc and the vapor is rapidly oxidized to zinc oxide in the process of being condensed to liquid, such as oxygen and carbon dioxide, the vapor must be condensed under the condition of no oxygen and carbon dioxide gas and almost zero. The zinc-forming smelting furnace meets the scientific principle, and the conceived novel smelting method, namely the zinc-forming smelting method, is scientific and very reasonable.

Secondly, the zinc accumulation pool of the zinc smelting method furnace is made of heat-resistant steel, and the heat-resistant steel can be normally used below 900 ℃. The impurities in the crude zinc produced by other zinc smelting furnaces mainly contain high cadmium content and lead. That is, cadmium and zinc have boiling points close to each other (cadmium 768.3 ℃ C., zinc 918 ℃ C.) and are therefore difficult to separate. When the temperature of the furnace is raised to 800-830 ℃ during zinc refining, cadmium vapor can be fully separated out. And because a small amount of lead is evaporated at the temperature of over 600 ℃, when the liquid zinc in the zinc accumulation pool of the furnace is reduced to 450 ℃, the lead does not have the evaporation phenomenon, and the lead becomes liquid lead. Lead and zinc have different specific gravity and layered characteristics, so lead is easy to separate out, and refined zinc can be smelted at one time by using the zinc smelting method furnace built by the scientific principle.

The electric furnaces include an electric arc furnace, an electric frequency furnace and an electric heating furnace, the electric frequency furnace is divided into a power frequency furnace and a high frequency furnace, heatingelements of the electric heating furnace are divided into a silicon carbide heating part electric furnace and a resistance wire electric furnace, the electric furnaces can convert electric energy into heat energy, carbon dioxide for decomposing furnace gas is carbon monoxide after heating the carbon into high-temperature carbon, and the energy is provided by the electric energy, compared with other electric furnaces, the electric arc furnace is superior to other electric furnaces, so the zinc smelting method furnace also uses a smelting furnace which integrates the electric arc furnace and the blast furnace into a whole, in the process of smelting zinc by a zinc smelting method, partial modification is carried out in the process of the originally designed closed zinc smelting furnace, in order to improve the yield and the benefit, a magnetic oxygen production device of a patent technology is adopted, zinc is smelted by an oxygen enrichment method, the red heat temperature of the electric arc furnace is utilized before raw materials enter the furnace, the preheating furnace is carried out at about 700 ℃ for smelting, the grass powder in the material ball is burnt to leave a plurality of micropores, the surface area of the material ball is increased, the speed of the smelting process is increased, the yield is increased, and the electric energy consumption is reduced.

Due to the adoption of the technical scheme, compared with the background technology, the method has the following beneficial effects:

1. the yield of the zinc-forming smelting furnace is lower than that of an electric arc furnace, a flat tank furnace and a vertical tank furnace in the background art, and how fast the result can be achieved. A plurality of: 35-45 tons of refined zinc and 6-10 tons of crude lead are produced in a small-sized closed zinc smelting furnace per day; fast: the smelting speed is high, namely, the roasted ore enters a furnace for smelting, and refined zincingots can be smelted within two hours or more.

2. Compared with the prior art of blast furnace zinc smelting, the zinc-forming smelting method furnace can achieve the advantages of good performance and saving. Well: the zinc content of the refined zinc with the one-time performance of the closed zinc smelting furnace is 99.9 percent and 99.99 percent. Saving: when smelting in a closed zinc smelting furnace, the zinc is not required to be sintered into blocks, and air is not required to be preheated to 700 ℃ for smelting in the furnace, so that time and labor are saved. On the material saving, the recovery rates of the zinc and lead contents in the ore are respectively more than 96 percent and more than 98 percent.

3. Compared with the prior art, the zinc-forming smelting furnace has simple and convenient operation conditions, does not use a lead pump and lead liquid as condensate, and combines national conditions with a closed zinc smelting furnace, so that the zinc smelting furnace is more medium and miniaturized.

4. Compared with the prior art, the zinc-forming smelting furnace utilizes electric energy and a zinc accumulation pool to smelt refined zinc at one time, changes the situation that the refined zinc cannot be smelted at one time in the technical field of pyrometallurgical zinc smelting, and saves time and energy compared with the prior art. In the background technology, crude zinc can only be smelted first and then sent to a refinery for refining after being cast into zinc ingots.

5. The carbon dioxide in the furnace gas of the zinc-making smelting zinc method furnace is decomposed into carbon monoxide, so that the content of the carbon dioxide in the furnace gas is lower than 0.5 percent, and the zinc vapor is ensured not to be oxidized into zinc oxide again when being cooled. Compared with the furnace gas in the prior art, the content of carbon dioxide is reducedby more than 9 percent. And carbon monoxide in the furnace gas can be collected for utilization.

6. Compared with the prior art, the zinc-forming smelting furnace has the advantages that the sintering system is not needed for ores, the preheating system and the lead-rain condensing system are not needed for air, the process is simplified, the equipment is reduced, and the total engineering investment is reduced. The zinc smelting furnace using the fine roasted sand ore as the source material changes the problems of heavy pollution and difficult smelting in the prior art of pyrometallurgical zinc smelting, the discharge amount of the furnace is very small, and the furnace contributes to environmental protection and great contribution in the pyrometallurgical zinc smelting technology.

The best way to realize the closed zinc smelting furnace by using materials and equipment is to build the furnace.

The zinc smelting furnace is an organically combined zinc smelting furnace with an electric arc furnace at the upper part, a hole at the bottom, a blast furnace at the lower part and no cap at the upper part. The periphery and top of the arc furnace and the periphery of the blast furnace are welded by steel plates 36, and the top arc furnace lid is sealed with graphite electrodes 4 by asbestos cords 5 and operated under strict supervision. Firebricks 2 are built under the electric furnace cover. The periphery of the blast furnace B is welded with a hot air layer 7 by using a steel plate 36, three air inlets 8 are arranged above the hot air layer 7, and three charging hoppers 9 are formed by rolling steel plates (phi 500) and comprise charging covers 10 and hopper valves 11. The three hoppers and the electric furnace lid were connected by bolts, and the carbon hopper 51 was made of a steel pipe (Φ 300) as an inspection hole of the furnace. The steel pipe is welded on the electric furnace cover, andis provided with a carbon bucket cover and a carbon bucket valve which are directly communicated to the side of the electrode in the electric arc furnace. The electric arc furnace A is composed of a transformer 12, a high-voltage control screen 13, a cable 19, an operation control console 14, a water pool 15, three graphite electrodes 4, nine electric plates 17, three electrode water jackets 16, an electrode steel sleeve 3 and an oil press 18. The electric arc furnace A is internally provided with a material warehouse 20, a graphite carbon brick clapboard 21 and nine discharging ports 22. The three zinc flue ports 23 are welded by steel plates 36, refractory bricks 2 are built inside, and graphite carbon bricks 6 are built into a circular masonry along the bottom of the electric arc furnace, wherein the circular masonry is composed of a furnace outlet hole (phi 600) at the upper end of the blast furnace B. The blast furnace B has a refractory layer made of refractory bricks 2 in the cavity 24(Φ 800). The outside is a hot air layer 7, a slag pool 25 is arranged below the hot air layer, three slag holes 26 are alternately used, a lead pool 27 is arranged below the hot air layer, three copper and silver outlets 1, three lead outlets 28 and four steel furnace feet 29 are arranged in the middle of the hot air layer. The blast system consists of a blast blower 30, an air inlet pipe 31, an air outlet pipe 32 and an air outlet pipe valve 53, and is distributed around the lower part of the blast furnace B according to the radian of 120 degrees, and three sets of smoke exhaust systems and condenser systems consist of a smoke zinc gas port 23 and an inverted water condenser 33: the water jacket is formed by welding the steel plate 36 and the steel pipe 55. The device is composed of an outlet pipe 35, an inlet pipe 34 and an outlet pipe valve 52, and the square area of the steel pipe of the device is equal to the square area of the zinc flue opening 23. The six zinc accumulation tanks 37 are made of heat-resistant steel. Each pool can contain liquid zinc and lead at 0.8T. A temperature-adjusting electric furnace 41 is arranged below the zinc accumulation tank, and a wheel drum arranged at the lowest part of the zinc accumulation tank 37 can move back and forth, so that the zinc accumulation tank is convenient to use alternately. The periphery of the zinc accumulation pool 37 is provided with a heat preservation layer 42, a zinc outlet 39, a lead and zinc outlet 40 and a thermometer 38 are arranged outside the pool, three safe flue openings 45 are arranged, the structure of a small water condenser 44 is the same as that of an inverted water condenser, and the accumulation pool 43 is arranged. Three smoke dust processors 46, exhaust fans 48 and the like which are matched with the smoke dust processors, and three smoke exhaust pipes 49 and three smoke exhaust pipe valves 54 are arranged outside the smoke dust processors. And are distributed around the upper part of the electric arc furnace a over an arc length of 120 deg.. The top of the electric arc furnace a and the blast furnace B. A high temperature thermometer 47 is respectively arranged at the middle upper part. The exhaust fan 48, the smoke exhaust pipe 49 and the smoke exhaust pipe valve 54 convey carbon monoxide in the exhausted smoke out to be used as fuel for roasting the ore. The connection mode of each part of the furnace is welding or bolt connection. The appliance part switches and the thermometer display are mounted on the operation console 14. The above materials and equipment constitute a zinc smelting furnace. The whole furnace is communicated with the outside except the air inlet part of the air blowing system and the air outlet part of the flue system, and all parts of the whole furnace operate under a closed condition. The material conveying system and the starting system of the whole furnace, the ore roasting system, the raw material forming system, the water supply and drainage system, the power supply system, the environment-friendly treatment system, the preheating sintering furnace and the gas washing field do not belong to the invention directly. And therefore will not be described in greater detail herein.

The finished zinc smelting furnace is divided into three types of large, medium and small: the zinc yield of the large-scale smelting furnace is more than 4 ten thousand tons every year, and the zinc yield of the medium-scale smelting furnace is more than 2 ten thousand tons every year. The attached drawing of the specification is a small-sized smelting furnace, and the annual zinc yield is more than 1 ten thousand tons.

The above are preferred examples of the present invention. A smelting furnace is built by utilizing the principle of a zinc-forming smelting method furnace, metal is smelted and reduced by a blast furnace, discharged gas is conveyed into various furnaces, carbon is heated to high temperature by various energy sources to decompose carbon dioxide, the carbon dioxide is reduced to a certain amount in the furnaces, and then the furnaces are cooled to obtain zinc and cadmium. The furnace is not only suitable for the size of the furnace volume, but also can be modified in various forms.

Claims

1. A closed blast furnace zinc smelting method is characterized by comprising the following steps of: the blast and oxygen enrichment in furnace chamber burn and oxidize carbon in raw material to release high heat 、 The lead-zinc oxide ore which is made into lumps in the furnace chamber is forced to be heated to 1300 ℃ to 1500 ℃, carbon monoxide formed by high-temperature carbon and carbon in the furnace chamber is subjected to reduction reaction with oxidized metal at high temperature to generateliquid metal lead and copper and gaseous metal zinc and cadmium, the liquid metal is discharged from furnace bottom metal, furnace slag is discharged from a slag bath outlet, and the gaseous metal,Carbon dioxide, carbon monoxide and dust flow out of the furnace gas into the electric heating furnace, the carbon dioxide in the furnace gas is almost completely reduced by coke, under the action of an exhaust fan (48), gaseous metal, furnace gas and dust are pumped into an inverted water condenser (33) through a zinc flue opening (23) to cool the gaseous metal zinc and cadmium into liquid zinc and cadmium, the liquid zinc and the liquid cadmium flow into a zinc accumulation pool (37) for refining, zinc is discharged and collected periodically, cadmium is refined in the zinc accumulation pool, cadmium is fully evaporated out, furnace gas is pumped into a small water condenser (44), cadmium vapor is cooled into liquid cadmium by the small water condenser, the liquid cadmium flows into a cadmium accumulation pool (43), the liquid cadmium is discharged and collected periodically, the furnace gas and the dust are pumped into a dust accumulator (46), the dust accumulator is accumulated with dust, the dust is discharged and collected periodically, the furnace gas enters the exhaust fan (48) and then is sent to a gas washing field through a smoke exhaust pipe valve (54).

2. A zinc smelting process according to claim 1, characterized in that: the electric furnaces comprise an electric arc furnace, an electric frequency furnace and an electric heating furnace, wherein the electric frequency furnace is divided into a power frequency furnace and a high-frequency furnace, heating elements of the electric heating furnace are divided into a silicon carbide heating element electric furnace and a resistance wire electric furnace, the electric furnaces are all devices for converting electric energy into heat energy, coke added into the electric furnace utilizes the heat energy converted from the electric energy to heat and keep the temperature of the coke between 1000 and 1200 ℃, carbon dioxide gas in furnace gas out passes through a red hot coke layer and is fully reduced into carbon monoxide The carbon dioxide in the gas is lower than 0.5%, and the gaseous substance and dust in the electric furnace are pumped into a water condenser connected with the upper part of the electric furnace and arranged at the rear of a zinc flue opening of the electric furnace.

3. A zinc smelting process according to claim 1, characterized in that: the zinc accumulating tank is used for accumulating zinc and heating liquid zinc and cadmium in the tank to 800-830 ℃ by utilizing a temperature regulating electric furnace below the tank for maintaining, so that the cadmium in the zinc accumulating tank is fully evaporated out and is pumped into a small water condenser together with dust in furnace gas.

4. A zinc smelting process according to claim 1, characterized in that: the exhaust fan has the function of sucking out furnace gas and dust in the electric furnace by using electric energy, and the furnace gas is treated by the equipment and then is pumped into the exhaust fan and then is sent to a gas washing field through a smoke exhaust pipe and an electric smoke exhaust valve.