阅读说明：本技术 一种从锡箔祭品的锡箔灰中回收再生精锡的工艺方法 (Process method for recovering and regenerating refined tin from tin foil ash of tin foil sacrificial offerings ) 是由 陈锐杰 陈晓杰 陈利昭 罗红权 于 2020-06-10 设计创作，主要内容包括：本发明提供一种从锡箔祭品的锡箔灰中回收再生精锡的工艺方法,由球团造粒、回转窑焙烧、电炉还原熔炼、粗锡精炼、结晶机提纯、炉渣烟化炉处理等步骤,科学有效的从锡箔灰最大限度的回收锡,并使锡箔灰内的其他固废资源得到科学环保处理,全面有效解决了锡箔灰的环境污染问题以及锡箔灰中锡的回收问题,充分的而有效的解决了固废资源的循环再生利用,不产生废物,不产生废水、废气、废渣,有效的解决了环境保护问题,发展了绿色循环经济,真正做到节能、降耗、高效、环保的目的的优点及效果。(The invention provides a process method for recovering and regenerating refined tin from tin foil ash of tin foil sacrificial offerings, which comprises the steps of pelletizing granulation, rotary kiln roasting, electric furnace reduction smelting, crude tin refining, crystallizer purification, slag fuming furnace treatment and the like, so that tin is scientifically and effectively recovered from the tin foil ash to the maximum extent, other solid waste resources in the tin foil ash are scientifically and environmentally treated, the environmental pollution problem of the tin foil ash and the recovery problem of tin in the tin foil ash are comprehensively and effectively solved, the cyclic recycling of the solid waste resources is fully and effectively solved, waste water, waste gas and waste residues are not generated, the environmental protection problem is effectively solved, the environment-friendly cyclic economy is developed, and the aims and effects of energy conservation, consumption reduction, high efficiency and environmental protection are really achieved.)

1. A process method for recovering and regenerating refined tin from tin foil ash of tin foil sacrificial offerings is characterized by comprising the following steps:

step a, pelletizing: adding tin foil ash containing 25-45% of Sn into a disc granulator, adding water accounting for 8-10% of the weight of the tin foil ash, and performing rotary rolling granulation to obtain a pellet granulation raw material with the particle size of 20-30 mm;

step b, roasting in a rotary kiln: b, adding the pellet granulation raw material in the step a into a rotary kiln for roasting, removing water and combustible substances to obtain roasted tin foil ash pellets containing 26.19-46.87% of Sn and smoke dust containing 2-3% of Sn, and storing the smoke dust in a smoke dust bin after collecting the smoke dust;

step c, electric furnace reduction smelting: taking the roasted tin foil ash pellets in the step b as a raw material, adding coal accounting for 12-13% of the weight of the raw material, limestone accounting for 2-3% of the weight of the raw material and iron powder accounting for 2-3% of the weight of the raw material as auxiliary materials, carrying out reduction smelting in an electric furnace to obtain crude tin containing 92-95% of Sn, 0.5-1.0% of iron, slag containing 2-3% of Sn and smoke containing 13-20% of Sn, and storing the collected smoke in a smoke bin;

step d, crude tin refining: adding the crude tin obtained in the step c into a refining pot, refining at the temperature of 250-260 ℃ for removing iron to obtain refined tin containing 98.5-99.5% of Sn, 0.04-0.05% of Fe and refined slag containing 70-80% of Sn and 20-26% of Fe, and returning the refined slag into the refining pot after collecting the refined slag;

step e, purifying by a crystallizer: d, separating the refined tin in the step d in a crystallizer, wherein the crystallizer is divided into 4 sections by temperature control, 1 section is 550 ℃, 2 sections are 450 ℃, 3 sections are 350 ℃ and 4 sections are 190 ℃ to obtain refined tin products containing 99.90-99.95% of Sn, tail tin alloy products containing 75-85% of Sn and smoke dust containing 75-80% of Sn, and the smoke dust is collected and then enters a smoke dust bin for storage;

step f, treating the slag by a fuming furnace: and c, adding the furnace slag in the step c into a fuming furnace, adding coal powder accounting for 10-12% of the weight of the furnace slag, pyrite auxiliary materials accounting for 5-8% of the weight of the furnace slag, then carrying out fuming treatment on the furnace slag, finally generating smoke dust containing Sn 40-45% and fuming furnace water-quenched slag containing Sn0.2-0.3%, and storing the collected smoke dust in a smoke dust bin.

2. The process method for recovering and regenerating refined tin from tin foil ash of tin foil sacrificial offerings as claimed in claim 1, wherein the diameter of the middle rotary kiln in step b is 1.6 m, the length is 20m, the rotation speed is 1 r/min, and the roasting temperature is 500-600 ℃; .

3. The process method for recovering and regenerating refined tin from tin foil ash of tin foil sacrificial offerings as claimed in claim 1, wherein in the step c, the electric furnace power is 1250-1300 KW and the electric furnace temperature is 1200-1500 ℃.

4. The process method for recovering and regenerating refined tin from tin foil ash of tin foil sacrificial offerings as claimed in claim 1, wherein the crystallizer in step e is an inclined horizontal spiral groove with a length of 6.5m, a width of 0.5m and a height of 0.5m, and the rotation speed is 1 r/3 min.

5. The process for recovering refined tin from tin foil ash of tin foil sacrificial offerings as claimed in claim 1, wherein step e is carried out by discharging refined tin product from the head end of the crystallizer and collecting the tail tin alloy product from the tail end of the crystallizer.

6. The process method for recovering and regenerating refined tin from tin foil ash of tin foil sacrificial offerings as claimed in claim 1, wherein the treatment temperature of the fuming furnace in step f is 1200 ℃ ± 10 ℃ and the treatment time is 4-4.5 hours.

7. The process of claim 1, wherein the fuming furnace in step f has an area of 4 square meters.

8. The process for recovering and regenerating refined tin from tinfoil ash of tinfoil sacrificial offerings as claimed in claim 1, wherein the smoke is collected by dust bag and stored in smoke bin for separate treatment.

Technical Field

The invention relates to the technical field of tin metal recycling, in particular to a process method for recycling and regenerating refined tin from tin foil ash of a tin foil sacrificial offering.

Background

The Chaoshan region of Guangdong province adopts high tin alloy containing more than 95.5% of Sn, and the metal foil is formed by soft mechanical rolling, and is generally called as 'Guangshi foil' for distinction. In order to ensure that the tinfoil does not break during further processing, and to improve the strength of the foil after rolling, the tinfoil is called as a backed tinfoil formed by adding white paper as a backing, and the thickness is generally less than 0.020 mm. The tin foil with or without paper backing can be used in different aspects or made into tin foil products for different purposes.

In the burning process of the memorial ceremony, the back lining is firstly burnt, then tin foil is burnt and melted, the temperature is above 320 ℃, and finally the back lining is changed into ash, the ash is the mixture of paper ash and tin foil ash, and is called as tin foil ash.

Early stage: during the lunar calendar festival, the sacrifice is small in scale and range, the sacrifice is made and incinerated, a small amount of tin foil ash is blown away with wind, and people rarely collect the tin foil ash without paying attention. The increase of demand and consumption promotes the diversification of the variety of the sacrificial offerings, so that the tin foil is artificially rolled by adopting tin alloy in regions such as Guangdong Chaoshan and the like, which gradually becomes an industry. The finished products of the tin foil paper are produced, and the sacrificial offerings are the most important varieties and form a certain market scale. With the increase of the quantity and the demand of the tinfoil paper, the collection and the utilization of tinfoil ash also attract attention, and the collection is accumulated more and more, and the climate is gradually generated. The method is characterized in that an aluminum pot and a ground furnace are heated by coal powder for reduction smelting in an earth method, tin is recovered from tin foil ash, and a finished product is crude tin for sale. The recovery method has small treatment capacity and low recovery rate. And when the crude tin enters the second stage, the crude tin containing 80% of Sn can be produced by adopting vertical tank gas smelting and reducing and recovering the tin in the crude tin. With the increase of the quantity of the tin foil ash raw materials, according to preliminary statistics, more than ten thousand tons of tin foil ash resources exist in China, the requirement cannot be met by adopting a small-scale method for smelting, producing and recovering crude tin by an earth method, a large amount of waste gas and waste residue are generated during the earth method smelting, a large amount of tin is directly discharged without being treated, the environmental pollution is very serious, and the method belongs to the restriction and the banning.

Disclosure of Invention

The invention aims to design a process method for recovering and regenerating refined tin from tin foil ash generated by tin foil worship in Chaoshan region aiming at the defects of the prior art, scientifically and effectively recovers tin from the tin foil ash to the maximum extent, scientifically and environmentally treats other solid waste resources in the tin foil ash, and comprehensively and effectively solves the problems of environmental pollution of the tin foil ash and recovery of tin in the tin foil ash.

In order to achieve the purpose, the invention provides a process method for recovering and regenerating refined tin from tin foil ash of a tin foil sacrificial offering, which comprises the following steps:

step a, pelletizing: adding tin foil ash containing 25-45% of Sn into a disc granulator, adding water accounting for 8-10% of the weight of the tin foil ash, and performing rotary rolling granulation to obtain a pellet granulation raw material with the particle size of 20-30 mm;

step b, roasting in a rotary kiln: b, adding the pellet granulation raw material obtained in the step a into a rotary kiln for roasting, and removing water and combustible substances to obtain roasted tin foil ash pellets containing 26.19-46.87% of Sn and smoke dust containing 2-3% of Sn, wherein the smoke dust is collected and then enters a smoke dust bin for storage, and the yield of the tin foil ash pellets and the yield of the smoke dust are 94-96% and 4-6% respectively;

step c, electric furnace reduction smelting: taking the roasted tin foil ash pellets in the step b as a raw material, adding coal accounting for 12-13% of the weight of the raw material, limestone accounting for 2-3% of the weight of the raw material and iron powder accounting for 2-3% of the weight of the raw material as auxiliary materials, and carrying out reduction smelting in an electric furnace to obtain crude tin containing 92-95% of Sn, 0.5-1.0% of iron, slag containing 2-3% of Sn and smoke dust containing 13-20% of Sn, wherein the smoke dust is collected and then enters a smoke dust bin for storage, and the yield of the crude tin, the slag and the smoke dust is respectively 25-45%, 50-60% and 5-15%;

step d, crude tin refining: adding the crude tin obtained in the step c into a refining pot, refining at the temperature of 250-260 ℃ to remove iron, and obtaining refined tin containing 98.5-99.5% of Sn, refined tin containing 0.04-0.05% of Fe, refined slag containing 70-80% of Sn and refined slag containing 20-26% of Fe, wherein the refined slag returns to the refining pot after being collected, and the yield of the refined tin and the refined slag is 90-95% and 5-10% respectively;

step e, purifying by a crystallizer: d, separating refined tin in the step d in a crystallizer, wherein the crystallizer is divided into 4 sections by temperature control, 1 section is 550 ℃, 2 sections are 450 ℃, 3 sections are 350 ℃ and 4 sections are 190 ℃ to obtain refined tin products containing 99.90-99.95% of Sn, tail tin alloy products containing 75-85% of Sn and smoke dust containing 75-80% of Sn, the smoke dust is collected and then enters a smoke dust bin to be stored, and the yield of the refined tin products, the tail tin alloy products and the smoke dust is 90-92%, 7.92-9.9% and 0.05-0.1% respectively;

step f, treating the slag by a fuming furnace: and c, adding the furnace slag in the step c into a fuming furnace, adding coal powder accounting for 10-12% of the weight of the furnace slag, pyrite auxiliary materials accounting for 5-8% of the weight of the furnace slag, and then carrying out fuming treatment on the furnace slag, and finally generating smoke dust containing Sn 40-45% and fuming furnace water-quenched slag containing Sn0.2-0.3%, wherein the smoke dust is collected and then enters a smoke dust bin for storage, and the yield of the smoke dust and the fuming furnace water-quenched slag is 3-7% and 93-97% respectively.

Preferably, the diameter of the middle rotary kiln in the step b is 1.6 m, the length of the middle rotary kiln is 20m, the rotating speed of the middle rotary kiln is 1 r/min, and the roasting temperature is 500-600 ℃.

Preferably, the power of the electric furnace in the electric furnace reduction smelting in the step c is 1250-1300 KW, and the temperature of the electric furnace is 1200-1500 ℃.

Preferably, the crystallizer in the step e is an inclined horizontal spiral groove body with the length of 6.5m, the width of 0.5m and the height of 0.5m, and the rotating speed is 1 r/3 min.

Preferably, the refined tin product of step e is discharged from the head end of the crystallizer, and the tail tin alloy product is obtained from the tail end of the crystallizer.

Preferably, the treatment temperature of the fuming furnace in the step f is 1200 +/-10 ℃, and the treatment time is 4-4.5 hours.

Preferably, the fuming furnace has an area of 4 square meters, and the slag treatment capacity per batch is 30 tons.

Preferably, the smoke dust is collected by a dust collecting bag and then enters a smoke dust bin for storage and separate treatment.

The invention has the advantages that: the process technology method can effectively aim at tin foil ash after burning Chaoshan tin foil sacrificial offerings, the collected tin foil ash contains 25-45% of tin and a small amount of Fe metal oxides, and the process adopts pelletizing, rotary kiln roasting, electric furnace reduction smelting, crude tin refining, crystallizer purification and slag fuming furnace treatment to form the components: pelletizing, namely performing pretreatment pelletizing on the tin foil ash powder raw material, so that dust flying during rotary kiln treatment can be reduced, air pollution and public nuisance of the surrounding environment of a production area are eliminated, and metal loss of the material in the treatment process is reduced; roasting in a rotary kiln, removing moisture and combustible materials from the pellet raw materials, improving the purity of the raw materials and forming a solidified raw material with certain strength, wherein the treatment capacity of the rotary kiln is 30 tons; reducing and smelting in an electric furnace, namely feeding the pellet raw material after roasting into the electric furnace, adding coal, limestone and iron powder for smelting, and smelting metal oxide (SnO) in the raw material under the reducing condition₂) Reducing the raw tin into crude tin containing 97-98% of tin and furnace slag containing 2-3% of tin; meanwhile, other metal oxides in the raw materials are reduced into metal, and the treatment capacity of the smelting furnace is 15 tons; refining the crude tin, wherein the purpose is to remove impurity iron in the crude tin by utilizing metal temperature difference, and the treatment capacity of a refining furnace is 15 tons; purifying by a crystallizer, and treating by the crystallizer to obtain a refined tin product containing 99.90-99.95% of Sns, wherein the treatment capacity of the crystallizer is 10 tons; treating the furnace slag in a fuming furnace, namely treating the furnace slag containing 2-3% of Sn in the furnace slag in the fuming furnace to finally obtain a fuming product containing 40-45% of Sn and a fuming furnace containing 0.2-0.3% of SnThe treatment capacity of the fuming furnace is 30 tons.

Finally, the full utilization and comprehensive recovery of resources are achieved, and finally, the harmless treatment of all raw materials of a factory is achieved. And finally, the water-quenched slag is sold to a cement plant as a raw material, so that resources are completely recycled and utilized, and the resource recycling is promoted.

Compared with the prior art, the method also has the following advantages and effects:

a) the production process of recovering and regenerating refined tin from the tin foil ash after burning the Chaoshan tin foil sacrificial offerings for industrial production has not been reported in literature at home and abroad,

b) the quality of the product produced by the process method completely meets all indexes of the national standard GB/T3131-2006,

c) the process method can ensure high recovery rate of the main metal tin, simultaneously can comprehensively recover nonferrous metals in materials, and can cumulatively recover precious metals such as Au, Ag and the like,

d) the processing method of the tinfoil ash capable of being fully recycled can increase the total supply quantity of domestic tin consumption, ensure the sufficient and stable supply of tin in the market, and reserve the cultural custom of Chaoshan for tinfoil paper on the premise of considering environmental protection.

e) By adopting the process method, the recycling of the solid waste resources of the tinfoil ash is fully and effectively solved, only usable substances are generated in the production process, no waste is generated, no waste water, waste gas or waste residue is generated, the environmental protection problem is well and effectively solved, and the effective recycling of the tin resources of the tinfoil paper is ensured.

f) Other useful metals contained in the tin foil ash can be recovered in the process of recovering the tin in the tin foil ash, so that resources are utilized to the maximum extent and effectively, green recycling economy is developed, and the aims and effects of energy conservation, consumption reduction, high efficiency and environmental protection are really achieved.

Detailed Description

The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.