The world's first new technology of full bottom blowing continuous copper smelting to achieve environmentally friendly ultra-low emissions

In July 2019, the world’s first new technology of full bottom blown continuous copper smelting was launched in Baotou, Inner Mongolia Huading Copper Development Co., Ltd. (hereinafter referred to as "Huading Copper"). This project is based on the old production line of PS converter in traditional copper smelting process. Above, it is a project that uses oxygen bottom-blowing furnace smelting→oxygen bottom-blowing continuous converting furnace to refining full-bottom-blown copper refining process technology. The successful implementation of the project has attracted attention in the domestic and even the world's copper smelting industry. One year later, the reporter interviewed Yuan Junzhi, general manager of Huading Copper, on the operation of the industry's first production line using bottom blowing technology to transform PS converters and the effective results of the new technology on environmental protection.

In order to fully implement the national environmental protection requirements, in February 2019, Huading Copper made a drastic transformation of the old production line of PS converter based on a series of environmental protection "combined punches" in the early stage. In July of the same year, PS was applied nationwide and even the world. The first-step copper smelting renovation project of "Three Continuous Furnace" initiated by the converter successfully landed in the enterprise. Over the past year or so, the project has not only successfully achieved production and compliance, but also by comparison, the company’s sulfur dioxide emission standard was 150 mg/m3 before the full bottom-blown copper process technology was put into production; after the production, the emission standard has been stable at 10 Within mg/cubic meter, it is far lower than 40 times the international standard and 10 times lower than the special discharge standard. Through understanding, the national emission standard for sulfur dioxide is 400 mg/m3; the "2+26" city stipulates that the special emission limit is 100 mg/m3. Although this standard does not include the Inner Mongolia Autonomous Region, the Inner Mongolia region requires its own special ranking restrictions. Huading Copper is also shouldering the mission of green development. It is determined to reform and innovate, and finally formed the world's first production line with full bottom blowing and full hot continuous copper smelting on the basis of PS converter, achieving special environmental protection emission limits Of ultra-low emission standards.

What kind of process technology is the triple furnace? New project and old production line

What are the advantages and differences of reconstruction

In the interview, Yuan Junzhi gave a concise and concise overview of the three-fired furnace process. The three-fired furnace, as its name implies, effectively connects the three furnaces of smelting, blowing, and refining in the copper smelting process. The traditional process of three furnaces is a three-stage production. , Did not realize the continuity of one-step copper smelting. Separate production has some drawbacks. First, it pollutes the environment, wastes energy, and restricts development. Because the old technology still needs to crane the steamed buns in production, and the steamed steamed buns cannot be collected during the lifting process, resulting in low-altitude pollution. The second reason is that the temperature of the bun's melt is too high, and it runs frequently at high altitude, which poses greater safety risks. The third is intermittent production. The amount and concentration of sulfur dioxide flue gas in the acid-making system varies from time to time, resulting in low conversion absorption rate, high exhaust emission indicators and high production costs and unstable. The biggest advantage of the new technology is that the three furnaces are connected through the launder to realize continuous one-step copper smelting, which not only saves energy and reduces consumption, but also runs stably, which meets the higher environmental protection requirements advocated by the country.

Yuan Junzhi told reporters that the so-called technological transformation mostly refers to the improvement and upgrading of the production capacity of the original production equipment, and the new projects generally refer to the projects that have passed the national environmental review and approval. He explained that the investment in new projects is relatively large. At present, due to various factors such as environment and resources, new projects are becoming more and more difficult now or in the future, and project renovation and upgrading will become a development trend. In addition, at present, nearly 80% of enterprises in the world’s copper smelting industry still use PS converters for smelting production. Due to the high energy consumption, low altitude and high pollution in converter production, new technologies are used to break the bottleneck of resource and environmental constraints. , Taking the road of green development is the general trend. In addition, in recent years, raw materials have been tight, low-grade raw materials have flooded the market, and processing fees have been falling all the way. In the face of many thorny problems, more and more companies are working hard on the ability to eat miscellaneous stoves in order to find profit growth points. Try your best to reduce costs.

In transformation and upgrading

What did Huading Copper take the lead

In Yuan Junzhi's view, although the PS converter can still continue production at the moment, it is difficult to play a competitive advantage. He emphasized that the transformation and upgrading of industrial enterprises has transformed not only the production environment, but also the competitive environment. So, how can we drive nearly 80% of the converter companies in the market to embark on a development path that seeks benefits from environmental protection innovation?

This is actually a big test. To deliver satisfactory answers, industry companies need to take the lead and take responsibility. In order to make the green transformation project a banner to lead the industry as soon as possible, expand the company's new economic growth points, and enhance the corporate brand effect, etc. Under the pressure and risks of the copper industry, it stepped forward without any experience to learn from, and became the first pioneer who had the courage to explore technological innovation.

Yuan Junzhi briefly introduced the development history of oxygen bottom blowing technology to reporters. In 2012, China Enfi Engineering Technology Co., Ltd. undertook the national "863" project to develop oxygen bottom blowing technology. This subject was closely connected with the theory and practice of industry enterprises. Based on numerous experiments, large and small, in 2014, bottom blowing The new continuous copper smelting process has been successfully developed in the non-ferrous industry. Yuguang Group applied this technology to build the first copper smelting production line, realizing a safe, reliable, green and efficient production mode. In response to the successful application of this technology, in 2016, an evaluation meeting of technological industrialization and applied scientific and technological achievements was held in Henan Province. Qiu Dingfan, the leader of the evaluation committee and academician of the Chinese Academy of Engineering, spoke highly of the technological achievements: “Continuous copper smelting technology is China’s major innovation, the low-altitude pollution problem of copper smelting that has plagued generations of people has been completely solved. This technology has many advantages such as indicators, equipment, and high degree of automation. It is evaluated as the highest level of international leadership. It is hoped that the bottom-blown copper technology will be in the world Carry forward."

In recent years, through development and practice, this process technology with China's independent intellectual property rights has become one of the world's competitive smelting processes, and has been successfully applied in more than a dozen new projects and renovation projects at home and abroad. , Huading Copper has conducted in-depth communication with the technology research and development unit China Enfi through in-depth market inspections and demonstrations, and according to the actual situation of the company, finally selected this technology for transformation and upgrading and entrusted Enfi to carry out the design. In terms of construction, Huading Copper is unique. The most different from other transformation projects in the industry is that Huading Copper is the first enterprise to transform and upgrade on the basis of the PS converter. The successful transformation means that the company will Become a beautiful "innovative business card", leading more companies currently adopting PS converters to boldly implement energy-saving technology upgrades; second, successful experience, can provide more companies with green system solutions; third, good technology The rapid and large-scale application will not only serve enterprises and benefit the industry, but also contribute to the protection of green ecology.

What kind of company is Huading Copper

Continuing this line of thinking, Yuan Junzhi clearly sorted out a series of large and small innovations implemented by Huading Copper over the years, and every reform seems to be inextricably linked with the bottom blowing technology. Huading Copper was established in 2003. In December 2004, it built a closed blast furnace production system with an annual output of 30,000 tons of blister copper and 115,000 tons of sulfuric acid. Due to backward production capacity, high energy consumption, poor working conditions, and environmental pressure Factors such as major factors, the company actively eliminated outdated smelting processes. Since 2009, Huading Copper has planned early and embarked on the road of reform to benefit from environmental protection. Three stages of upgrading and transformation. Yuan Junzhi showed reporters a group Group data: The first stage, that is, in 2009, the company eliminated the backward production capacity of blast furnace copper smelting, and built oxygen-enriched molten pool smelting, converter blowing, and anode furnace refining supporting 100,000 tons of electrolytic cathode copper and 30,000 tons in line with national industrial policies Tons of copper rods and other projects. At that time, in order to extend the industrial chain and self-pressurize to achieve the in-depth development of the industrial chain, the 30,000-ton copper rod production line not only increased the economic value-added and deep processing capacity of the enterprise’s products, but also realized that the production could not leave the house. It can digest the pollution points on the spot, realize the space for energy saving, and promote the common development of ecology, economy and society. In Yuan Junzhi’s words: “The team went deep into the scene every day. In view of the outstanding shortcomings of the stove’s ecological environment, they lowered themselves and tried to reform from one small problem. When they encountered problems, they continued to summarize and eliminate them. Repeatedly seeking breakthroughs, no one knows the future development of the company. Everyone always believes that the path of technological innovation cannot be wrong."

To the second stage, in 2016, Huading Copper added a Φ4.4×18m oxygen bottom-blowing smelting furnace to the main smelting plant, and upgraded the original Φ3.8×15m bottom-blowing smelting furnace to a bottom-blowing continuous converting furnace. Used for copper matte blowing. At that time, in order to directly flow the hot copper matte produced by the smelting furnace into the converting furnace through the launder for blowing, the two furnaces were arranged in a stepped manner, forming an oxygen-rich bottom blowing smelting + bottom blowing Continuous blowing + fixed reflective anode refining process, this combination of operations is more energy-saving and environmentally friendly, which in a certain sense laid the groundwork for the continuous production of the three continuous furnace process technology; Huading Copper chose bottom blowing continuous blowing Furnace used for copper matte blowing production can be described as a big test, because at that time in the copper smelting industry through the bottom-blowing furnace production, no company can achieve full-hot material process production, but to break the full-hot material production has always been The goal that Huading people want to achieve is that in order to achieve a deeper protection of resources and the environment, Huading Copper's biggest advantage in bottom blowing technology is that Yuan Junzhi worked on bottom blowing furnaces in other companies in the industry many years ago. Have a certain degree of control ability. Second, China Ting has a team that dares to innovate and is not afraid of hardships, and has a certain technical guarantee. Huading began to boldly deploy and implement innovations, and achieved effective breakthroughs in the production of large oxygen lances and full-hot material production. Some bottlenecks that restricted the environment were broken. In practice, Huading Copper's production has become cleaner. Energy consumption is reduced, and a lot of acid mist lost in the air is effectively collected and utilized by energy-saving and environmental protection technologies.

By the third stage, in February 2019, in order to achieve the perfect combination of the three bottom blowing processes of bottom blowing smelting furnace, bottom blowing continuous converting furnace and bottom blowing refining furnace, and to achieve continuous production of all hot materials, the safe, safe, and Energy saving, environmental protection, and high efficiency require benefits. Based on years of successful experience in bottom blowing technology and an attitude of seeking innovation and change for development, Huading Copper resolutely eliminated the fixed reflective anode furnace and replaced the original two ( Φ3.6m×8.1m) PS converter was upgraded to a bottom-blowing rotary anode furnace (Φ3.6m×10m), and finally "opened up the last mile", realizing the smelting, blowing, and refining three furnaces in series. The copper matte produced by the smelting furnace flows into the continuous converting furnace through the chute for blowing, and the blister copper produced through the chute flows into the bottom blowing refining furnace for fire refining and casting. Three continuous furnace full bottom blowing continuous smelting Copper production process. The green and clean one-step copper smelting ensures the safety and efficiency of the slag discharge process, and the low-altitude pollution has been further improved. The change in production methods has made Huading Copper finally take a firm step towards green development.

Through more than 10 years of unremitting efforts, Huading Copper has developed an annual raw material processing capacity of 750,000 tons, sulfuric acid 600,000 tons, and an annual production capacity of 500,000 tons of copper slag. It supports the 30,000 tons of electrolytic copper industry chain. , Drove the high-quality development of the 100,000-ton continuous casting and rolling copper wire drawing production line for key industries, among which high-end products have been used in products such as aerospace and smart phones, achieving an annual output value of 6 billion yuan and an annual profit and tax exceeding 100 million yuan.

Recalling the hard past of the innovation process, Yuan Junzhi was a little bit emotional. He said that in order to bite down some of the "hard bones" that restricted the technical field of the industry, there are no shortcuts. If you want to continue to develop, you must constantly surpass. For example, in 2016, the company chose bottom blowing continuous converting technology to add a Φ4.4×18m oxygen bottom blowing smelting furnace to the main smelting plant, and upgrading the original Φ3.8×15m bottom blowing smelting furnace to bottom blowing continuous blowing The furnace was used for copper matte blowing for technical transformation as an example. Before the transformation, the project team had a lot of hardships. In order to win a series of prepared battles, during the critical period of tight time and heavy tasks, Huading people arranged the lines in advance. Every aspect of the work that hinders the transformation process will not be left dead; since the project was completed, the project team used the large oxygen lance for production practice. Everyone was full of energy at the production site where the machine roared and the furnace was red. , Tired and sleepy, lay a bag on the spot and fall asleep.

What do they do for

It turned out that in the design of the copper smelting industry at that time, whether it was smelting furnaces, converting furnaces, or continuous bottom blowing technology, it always followed that the diameter of the oxygen grab should be small rather than large, the ventilation area should be small rather than large, and the number of oxygen lances should be more than less. In order to break the inherent thinking, the Huading team strives to adopt a large oxygen lance for practical application. In those days of passion, it is very difficult to open a door to success. The furnace has been working for less than 24 hours at the beginning. It was repeatedly burned, causing the furnace to fail to produce continuously. In the face of difficulties, Huading people do not give up, do not get discouraged, insist on the same idea of ​​the big oxygen lance, the same test direction, practice again and again, and maximize the technology connection time after time. Through countless repeated demonstrations, we have found the "balance of the oxygen lance" In the end, the independent innovation of the large oxygen lance production has achieved a breakthrough in the industry, and an effective breakthrough has been achieved in the production of all-hot materials; through comparison with the design requirements, according to the 100,000-ton continuous conversion furnace, the oxygen lance needs 9 ~10 oxygen lances with a diameter of 48 mm and an oxygen delivery rate of 800 cubic meters to 1000 cubic meters/only to play the role of practical production, and Huading Copper has realized the innovation of reducing 10 oxygen lances to 3 Oxygen lance, the diameter of the oxygen lance is designed to be more than 70 mm, and the oxygen delivery capacity is about 4000 cubic meters to 6000 cubic meters per piece.

Secondly, while breaking through the production of large oxygen lances, especially when Huading Copper chose bottom-blowing continuous blowing technology to achieve full-hot material production, industry enterprises questioned voices one after another, although the two major breakthroughs are for the industry It can be said to be positive, but because the hot material production theory is not recognized by practice at the beginning of the new process design, only cold material production design can be used. The cold material process is to cool the matte produced by the smelting furnace into a solid, perform mechanical crushing, and then Use a forklift to transport the broken matte to the production line and add it to the furnace through a belt. In Huading’s opinion, production with cold materials is less difficult and less risky. It can solve the heat balance problem of the furnace, but the continuity of the conversion furnace is not It truly reflects its value. Huading people understand that it is very difficult to realize the production of full thermal materials, and they must overcome the difficulty of 100% thermal materials. During that time, the innovation team worked on the parabolic curve of the melt, and overturned the data again and again. After more than a month of repeated exploration by the team, the problem of flow velocity was overcome. The problem that the furnace had been leaked in a few minutes was overcome. In the end, the production process realized full-hot material production. The Huading people rushed to report amidst cheers.

The effective breakthrough of large oxygen lance and full heat flow production has further improved the technological progress that restricts the technical field of the industry. With the first implementation of the full bottom blowing technology in the enterprise, the innovation-driven Huading people are not arrogant or impatient, and face resource shortages. Huading people began to do their homework on impurity removal, etc., by consulting a large number of references and materials related to impurity removal in copper pyrometallurgy, and comparing their own company’s product test results, etc., finally the company’s refining furnace adopts bottom blowing mode and special The slagging method makes the removal of impurity elements in the refining process significant, with the removal rate of Pb in 70%~90%, As in 50%~90%, Sb in 50%~70%, and Bi in 30%~50% Compared with the traditional method, it is about 80% higher, and the competitiveness is undoubtedly more prominent.

How to let the industry share the fruits of reform and development

The Huading people who have gnawed hard at the bottom blowing technology have opened up a new era of leading the industry to transform the old PS converter production line with new technology to benefit from environmental protection.

Yuan Junzhi said that the traditional process of converter blowing has restricted the links, and the closed chute has now achieved full-heat production. The low-altitude pollution caused by the transfer of materials during the smelting and blowing process has been improved to a certain extent. At the same time, the copper smelting waste gas and the environment The flue gas and sulphuric acid tail gas are all discharged after being desulfurized by the power wave desulfurization system; in addition, the enterprise production wastewater and domestic sewage are used for slag slow cooling after treatment, and all are not discharged; the tailings and other industrial solid wastes are temporarily stored External sales and comprehensive utilization, and all hazardous wastes such as neutralization slag are outsourced for safe disposal or comprehensive utilization. After the implementation of the project, the amount of heavy metal pollutants in the atmospheric pollution of Huading Copper has been reduced to a greater extent than before the technological transformation.

When the environmental protection benefits are further manifested, in order to let more copper smelting enterprises using PS converters have a comprehensive understanding and understanding of the technology, Huading Copper has responded to the technical innovation of copper smelting with full bottom blowing and full thermal continuous process. Huading people handed over a report card that satisfied the industry.

One is to break the restriction of complex mineral materials. Through the project transformation, the company solved the problems encountered in the production of high-sulfur copper concentrate, low-sulfur copper concentrate, oxide ore, gold concentrate, silver concentrate, high-arsenic ore, high-silicon ore, lump ore and other low grades. The complex problems of mineral materials, the new process has strong ability to eat impurities, and can recycle the relatively high valuable metals such as copper, gold and silver in difficult-to-remove mineral materials. Through production practice, Huading Copper used the rich heat treatment of high-grade cold copper in the bottom-blowing continuous converting process, and the ratio of ore copper to cold copper reached a maximum of 1:1, which truly solved other continuous blowing The problem that cold copper cannot be added in the refining process or the addition ratio is too low can reduce the cost by 10% to 20%.

The second is strong demixing ability. Huading Copper realized the first application of bottom blowing technology to rotary refining furnaces, instead of venting bricks, breaking through the traditional venting brick refining and mixing strength, low efficiency, and low life. Oxygen lances used in blowing and refining all adopt the bottom blowing mode. Huading Copper has improved the oxygen lance and added mixed gases such as nitrogen, natural gas, oxygen and air in appropriate proportions to finally make the smelting slag pass through the intense mechanical Stirring can effectively remove and volatilize impurities.

In terms of impurity removal ability, Yuan Junzhi elaborated on the data of the impurity removal process in a very detailed manner. He said that the oxygen concentration of the mixed gas fed into the furnace during the bottom blowing smelting stage is about 75%, and the pressure is between 0.4 and 0.7Mpa. The oxygen concentration of the mixed gas sent into the furnace in the bottom blowing continuous blowing stage is about 25%~30%, and the pressure is between 0.6~0.8Mpa, which means that the high oxygen potential melt requires more oxygen for dissolution. During the reaction, oxygen directly or preferentially oxidizes Cu to CuO2 as the carrier for transmission, precisely because the gas required for bottom blowing smelting, bottom blowing continuous blowing and bottom blowing refining are all blown into the molten pool from the bottom oxygen lance and pass through the melt. Stir vigorously, so that Pb, Zn, As, Sb, Bi, which are very difficult to remove impurities, volatilize into the flue gas after oxidation, and the final removal effect is very significant.

The third is to break the problem that the traditional process of SO2 in the acid production process is high and sometimes low, and it is difficult to maintain a balanced production. The use of full bottom blowing continuous copper smelting because of continuous and stable production, the hot melt produced by each furnace can flow from the previous production link to the next production link in an orderly manner. The stable and continuous production can effectively guarantee the production life of the furnace; in addition, All high-temperature solutions are transported by a chute, and the chute is fully enclosed during the transportation process, which completely solves the problem of low-altitude flue gas pollution. At the same time, because of the continuity of the sulfur dioxide concentration and gas volume, it ensures high SO2 concentration and stable acid production in the same environment.

Compared with the PS converter, the flue gas volume is only 1/3 of that of the converter. Because the oxygen-enriched concentration of bottom-blowing smelting can reach 75%, even if the bottom-blowing continuous blowing operation, the flue gas volume is still in a stable state, which is beneficial to acid production; Compared with the national emission standards, the SO2 concentration of tail gas emission is below 10mg/m3, which is more than 10 times lower than the national ultra-low emission standard of 100mg/m3. In particular, the SO2 occurrence rate of this process has been reduced from 0.4% to 0.2%, to a certain extent The reduction in the amount of sulfuric acid mist eliminates the need to configure a professional flue gas collection system, and ultimately achieves a win-win situation for cost and environmental protection.

In particular, with the continuous improvement of smelting scale and comprehensive profitability, in terms of comprehensive energy consumption indicators per ton of copper, in accordance with national standards, the comprehensive energy consumption standard for mineral anode plates has established an energy consumption standard of 340kg standard coal. It is 220kg standard coal, and the advanced value is 190kg standard coal. In the process of practicing high-quality development, Huading Copper is step by step to benefit from energy-saving and environmental protection technology, and finally realized the energy consumption per ton of copper is only 106.490kg standard coal.

At present, Huading Copper, which uses data to show its achievements, has been awarded "China Energy Diagnosis and Energy Management System Construction Demonstration Enterprise" "Model Harmonious Labor Relations Unit in Inner Mongolia Autonomous Region" through years of intensive work in the technical field. "Inner Mongolia Autonomous Region Non-public New Type Enterprise Award", "Inner Mongolia Autonomous Region Integrity Enterprise", "Baotou City Well-known Trademark", "Baotou City Ankang Cup Winning Unit", "Baotou City and Rare Earth High-tech Zone Non-public Economy Party Building Advanced Enterprise", "Rare Earth High-tech Zone Five A number of honorary titles such as a labor award. At the same time, many technical research and development teams of the company have obtained 2 national invention patents and more than 20 utility model patents because of their bold innovations. The application of these patents has enabled the company to develop rapidly Tao".

Looking back on the past, the Huading people who have tasted the sweetness of innovation are currently working hard on improving operating efficiency, reducing system energy consumption, improving oxygen lance structure and extending furnace life, looking for shortcomings, in the words of Yuan Junzhi: "No technological innovation At the end, innovation is to continuously sprint to new starting points one after another. As a manufacturer, if you want to innovate and lead, it is by no means a simple slogan, nor is it a problem that can be solved simply by relying on one or two key technologies. The in-depth integration of production, education and research will ultimately make innovation a systematic project. Continuous improvement in practice is the fundamental element of the company's high-quality and sustainable development."