ABSTRACT: FLASH SMELTING has gradually replaced the status of reverberatory furnace and blast furnace since its appearance in 1949. It has also become the most competitive smelting technology used in copper metallurgy today and is considered the most standard clean copper smelting process. The requirement of flash smelting is very strict to the charge preparation. The drying of concentrate in production usually adopts rotary kiln drying and airflow drying. CHARACTERISTICS OF FLASH SMELTING:

1. FLASH SMELTING FLASH SMELTING SINCE ITS INCEPTION IN 1949 in Otokumpu, Finland, through continuous improvement, gradually replaced the status of reverberatory furnace and blast furnace. It has also become the most competitive smelting technology used in copper metallurgy today and is considered the most standard clean copper smelting process. The requirement of flash smelting is very strict to the charge preparation. The drying of concentrate in production usually adopts rotary kiln drying and airflow drying. The characteristics of flash melting are: (1) when flash melting is a suspension melting, gas-liquid-solid three-phase reaction process is completed in the reaction Tower 1 ~ 2 s, the oxygen-enriched application speeds up the reaction speed, so the productivity is high; (2) flash smelting is a continuous and stable process, with high concentration of SO2 and stable composition of flue gas, which is favorable for acid production and recovery of s; (3) the greatest advantage of flash smelting is to make full use of the huge surface energy of copper concentrate, that is to maximize the use of the concentrate’s own heat of reaction. Self-heating smelting can not only reduce energy consumption and improve production capacity, but also reduce the amount of flue gas. (4) high degree of automation, long production stable furnace life. The AíSA AíSA process was developed in the 1980s by Mim and CSIRO, the Commonwealth Scientific and Industrial Research Organisation. AíSA smelting method copper flash smelting method, noranda method, such as the process can be controlled by computer. AíSA smelting process short process, simple equipment, so the control system is relatively simple. AíSA processes a wide range of raw materials, including MIM’s own brass concentrates, converter slag concentrates and various other purchased copper concentrates. AíSA smelting process in the melting process, as long as the flux and slag amount are controlled, and the mixture of copper matte and slag produced in the holding furnace has enough time to clarify, slag containing less than 0.6% copper. 

3. Baiyin Copper Smelting Method Baiyin copper smelting method is a new copper smelting method to obtain matte from copper concentrate. The research on Baiyin Copper smelting method began in 1972. At the beginning of 1975, the design of industrial production scale began with the design of a device capable of handling 300 tons of burden per day. In 1980, the silver non-ferrous metals company replaced the traditional reverberatory furnace smelting method with the silver smelting method and built a silver smelting furnace capable of handling 800 tons of burden per day on the basis of the former reverberatory furnace. One of the characteristics of the silver-smelting process is that the fuel requirements are not strict. In the past, heavy oil was used as fuel, and a burner was arranged at the head and the middle part of the top of the stove. The advantages of Baiyin copper smelting process are: (1) the utilization rate of sulfur in raw materials can reach more than 70% , the concentration of sulfur dioxide in flue gas is relatively high, the concentration of sulfur dioxide in flue gas produced by furnace can reach 8% ~ 9% , and it can reach 5% ~ 7% at the outlet of flue gas exhauster, it can meet the requirements of acid production and reduce the pollution to the environment. (2) good heat utilization and less fuel consumption, the added heat is only 50% of that of the furnace melting. The law is not strict in fuel requirements and conforms to China’s energy policy; (3) it is not strict in moisture requirements for raw materials, and raw materials do not need to be fully dried, and the raw materials preparation and transportation process are relatively simple and the smoke and dust rate is relatively low; (4) there are few auxiliary equipment for silver-smelting Copper Process, therefore, the investment in infrastructure is low, the silver-smelting furnace is a fixed type furnace, and the structure is simple; (5) the silver-smelting process not only produces low copper content slag, does not need to be depleted, but also can impoverish converter slag, compared with other enhanced smelting is also a prominent advantage;

 4. PS converter is the main process of copper and sulfur blowing in ausmelt copper smelting process, which needs to transport the melt in a metallurgical package and has poor sealing of furnace mouth, so 2 flue gas pollution and safety problems. AUSMELT blowing technology is a new technology after Mitsubishi method and flash blowing technology. Fixed metallurgical furnace is used instead of converter. Melt is transported by Chute. The Chute has a closed hood and the mouth of the furnace is well sealed, in the operation process, the unorganized emission of flue gas is less, and can be centralized recovery, environmental protection problems are effectively solved, and high level of automatic control. Its characteristics are as follows: (1) the quality of raw copper can be produced by continuous blowing, the operation mode is simple, the temperature of the process control furnace and the concentration of SO2 in the flue gas are relatively stable, and the environmental protection effect is good; (2) because there is no liquid copper phase Matte, (3) the continuous blowing increases the blast time rate of the blowing furnace, which creates the conditions for increasing the production capacity; (4) at present, the technology still has the problems of high copper content in slag and low direct yield. Shuikoushan copper smelting process in the early 1970s, the Shuikoushan Mining Bureau designed and built a small-scale copper smelter with an annual output of 5000t in order to solve the smelting problem of its own uranium-bearing copper concentrate, at that time, because there was no new process suitable for small-scale copper smelting, the closed blast furnace process which was widely used in China was chosen. After more than two years of theoretical analysis, small-scale experiments and equipment research, the conditional experiments were carried out in a 50 t furnace charge per day, and a long-term semi-industrial experiment was carried out from 1991 to 1992, we have achieved very satisfactory technical and economic indicators. In 1994, he was awarded China Patent Excellence Award by China Patent Office. Shuikoushan copper smelting method is a copper smelting bath, the smelting furnace is a horizontal cylindrical furnace, steel shell lined with chrome-magnesia brick, the furnace body has a transmission device, can rotate 90 ° roommate feeding mouth, smoke exhaust mouth, slag discharge mouth, sulfur discharge mouth, bottom equipped with oxygen lance, oxygen Gun and sleeve brick can be replaced, end wall fuel burner for use when blowing and heat preservation. Materials in the furnace at the same time complete heating, melting, oxidation, slag, matte-making and other processes, mass and heat transfer efficiency. The copper smelting process in Shuikou adopts the technology of bottom matte blowing and jet oxygen lance, which can recover arsenic at high speed. 

Source: Changjiang Copper Net