Beneficiation and comprehensive utilization of vanadium-titanium magnetite

First, resources

Divided magnetite iron ore resources, hematite (martite) stone, brown iron, titanium magnetite ore, diamond ore, five kinds of mineral components by.

The vanadium- containing titanium magnetite ore is mainly formed in a basic, ultra-basic intrusive deposit (magma-type iron deposit), and the ore is characterized by being rich in vanadium and titanium. The main resource countries are China, Russia, Canada, Norway, South Africa, the United States, Finland, Brazil, etc. The secondary sand deposits are mostly distributed in the vanadium-titanium magnetite resources of Australia, India and African countries. Due to the different ore characteristics, Its development and utilization of the side surface is also different in a part of vanadium-titanium magnetite, the vanadium is very high, focusing on the recovery of vanadium, such as Finland's Otatmmki (Otatmmki), other iron and titanium as a by-product; MapocLs mine in South Africa The ore contains V 2 O 5 1.4% to 1.7%, Fe 53% to 57%, and TiO 2 12% to 15%. Vanadium products have been used in a large number of applications, but titanium minerals have not been exploited by Canadian titanium magnetite ore, but Quebec The Alard Lake mine is an ore of ilmenite containing very fine flaky hematite (15% of the ore) structure, called hematite iron ore, used as Sorrel ( The Sorel) smelter produces the raw materials for the famous Sorell high-titanium slag. The large-scale development and utilization of the vanadium-titanium magnetite ore in Katschkanar, Russia, has a processing capacity of 45 million t/a and only produces iron-vanadium concentrate (Fe 62%, V 2 O 5 0.5% to 0.7%). It is used as raw material for the production of the Lower Tajir and Qiusov smelters. China's Panzhihua vanadium-titanium magnetite produces iron-vanadium concentrate, titanium concentrate and magnetic cobalt concentrate, which are mainly used as raw materials for the production of Panzhihua Iron and Steel Company and related titanium dioxide factories.

The reserves and distribution of foreign vanadium-titanium magnetite deposits have long been reported in more detail. These deposits are widely distributed in China, with abundant reserves. The reserves and extractions rank third in the national iron ore mines. The proven reserves are 6.19 billion tons, mainly distributed. In Panzhihua-Xichang area of ​​Sichuan, Chengde area of ​​Hebei, Hanzhong area of ​​Shaanxi, Fuyang of Hubei, Xiangyang area, Xingning of Guangdong and Daixian County of Shanxi. Among them, the Panzhihua-Xichang area is the main metallogenic belt of the country's vanadium-titanium magnetite, and is also one of the important production areas of similar deposits in the world. The metallogenic belt is about 300 km long from north to south. There are 7 large and extra-large deposits and 6 medium-sized deposits. The iron-titanium and vanadium in the ore are available for comprehensive utilization.

The types of Chinese vanadium-titanium magnetite deposits and the chemical composition of ore are shown in Table 1.

Table 1 China's vanadium-titanium magnetite deposit type hard chemical composition ω /%

Second, vanadium-titanium magnetite beneficiation

The development and utilization of vanadium-titanium magnetite resources is firstly sorted by ore. The aim is to have such a composite ore more monovalent minerals according to their different properties, sorted into various products, which is adapted to integrate rich iron, titanium and relevant manufactured metal products processing dressing, Such as iron and vanadium concentrate, titanium concentrate, sulfur-cobalt nickel concentrate and gangue minerals and other products.

(1) China's vanadium-titanium magnetite ore dressing

The large-scale development and utilization of vanadium-titanium magnetite in China begins with the scientific research work on the comprehensive utilization of vanadium-titanium magnetite mineral resources in Panzhihua-Xichang area, and has achieved a series of major scientific research achievements and established a complete set of vanadium-titanium magnetite. Selecting and smelting process, using iron-vanadium concentrate to produce blast furnace pig iron and vanadium slag; using titanium concentrate to produce sponge titanium and titanium dioxide; using sulphur-cobalt-nickel concentrate to make cobalt nickel and its oxide; from titanium to vanadium Recovering bismuth , gallium, etc.

The beneficiation process of vanadium-titanium magnetite in Panzhihua-Xichang area

The main basic characteristics of the study, the ore containing magnetite, ilmenite, spinel and platy ilmenite as a whole mineral phase, rich into iron and vanadium concentrate (titanium iron Mineral concentrates; sulfides in ores can be integrated with sulphur-cobalt-nickel concentrates (an ancient vanadium-titanium magnetite concentrate); granular ilmenite in ore can be enriched with titanium concentrates (including cobalt-nickel and various precious metal minerals) Sulfurized mineral concentrate). Vanadium, gallium and antimony are non-independent minerals, mainly in the presence of isomorphism in titanomagnetite and pyroxene. For the experimental research of the ore dressing production enterprise, the ore dressing process of the iron ore concentrate was obtained after the crushing of the ore, a closed-circuit grinding to -0.4μm, secondary magnetic separation, and one sweeping; on this basis, from the magnetic Three sorting processes for the recovery of granular ilmenite from tailings: 1 spiral beneficiation-flotation (sulfurized minerals)-Electrical selection process; 2 strong magnetic separation and spiral beneficiation-flotation (sulfurized minerals)-Electrical selection Process; 3 chute and spiral beneficiation - flotation (sulfurized minerals) - electrification process. On this basis, the selection of the ore dressing plant of Panzhihua for processing the l3.5 million t/a ore and the titanium ore of the titanium ore concentrate with a capacity of 200,000 to 300,000 t/a are used for the three-stage open-circuit crushing process, and the grinding operation uses a closed-circuit grinding process. The three-stage magnetic separation process obtains a magnetic separation concentrate (iron-vanadium concentrate), and the magnetic separation tailings adopts a spiral beneficiation-flotation electric separation process to obtain a sulfur drill concentrate and a titanium concentrate product.

The Hebei Dumiao and Heishan vanadium-titanium magnetites are separately sorted by the Shuangtashan Concentrator and the Heishan Concentrator. Both iron and vanadium concentrates and titanium concentrates are available for use as ironmaking raw materials for Chengde Iron and Steel Co., Ltd. Raw materials for vanadium enterprises.

The iron and vanadium concentrate produced by Taihe vanadium-titanium magnetite in Xichang, Sichuan Province is used as raw material for Chongqing Iron and Steel Company.

Sichuan Baima and Hongge vanadium-titanium magnetite have been tested in the beneficiation industry respectively, and both iron-vanadium concentrate, titanium concentrate and sulphur-cobalt concentrate products are available.

Vanadium-titanium magnetites such as Hanzhongyang County in Shaanxi Province and Xingning District in Guangdong Province are currently in preparation for the pre-development period.

The chemical composition of the vanadium-titanium magnetite beneficiation products in the main areas of China is shown in Table 2.

Table 2 Chemical composition of China's vanadium-titanium magnetite ore dressing products ω /%

(II) Foreign vanadium-titanium magnetite ore dressing and comprehensive development The use of foreign magmatic vanadium-titanium magnetite deposits has not yet been fully developed and utilized.

The vanadium-titanium magnetite deposit in the Sanford Lake area of ​​New York, USA contains an average of Fe 34%, TiO 2 18%-20%, and V 2 O 5 2 0.45%. In 1942, the Macintyle concentrator was built, and the iron-vanadium concentrate was produced by magnetic separation method containing Fe 59%, TiO 2 9%-10%, V 2 O 5 0.7%, using a shaker and dry magnetic Select and fine mud flotation to produce titanium concentrate containing V 2 O 5 44% ~ 48% of the product. This deposit has played an important role in the production of ilmenite in the United States and has obvious economic benefits.

The vanadium-titanium magnetite deposits in the Egersund Flekefjord region of southwestern Norway are widely distributed, with the Tellnes deposit being the most economically important. Since its commissioning in 1960, the mine has produced 900,000 tons of titanium concentrate per year and is the largest producer of ilmenite in Europe. The magnetic separation method is used to produce iron and vanadium concentrate containing Fe 65%, and the production of sulfur nickel concentrate by flotation method contains Ni 4% to 45% and titanium concentrate containing TiO 2 45% to 45.5%.

The Otamnaki vanadium-titanium magnetite ore of Rautaruukioy in central Finland contains an average of Fe 35% to 40%, TiO 2 13%, V 2 O 5 0.38%, magnetically selected and floated. The iron-vanadium concentrate is selected to contain Fe 69%, TiO 2 2.5%, V 2 O 5 1.07%, titanium concentrate containing TiO 2 45%, sulfur concentrate containing S 45%, Co 0.6% iron vanadium concentrate The extraction of vanadium from water and metallurgy into European countries has a large market share.

The vanadium-titanium magnetite in the Bushveld region of northeastern South Africa has been extensively exploited. Among them, the Mapochs mine has an annual mining capacity of 3 million tons, which is crushed and sieved, and is rich in monoliths 32-6. Mm power supply furnace iron production plant for the production of high vanadium iron water; -6mm powder ore after magnetic separation and enrichment for the production of sheet V 2 O 5 products. South Africa uses two different processes to process vanadium-titanium magnetite to produce steel and vanadium products. One is a pig iron vanadium slag-steel process, and the other is a sodium roasting leaching process for a piece of V 2 O 5 . South Africa's vanadium products account for the world's largest output, supplying Europe, the United States and Japan.

The hematite and ilmenite ore in the Alard Lake region of eastern Quebec, Canada, contain an average of 35% TiO 2 and 40% Fe. The content of titanium and iron oxide in the ore is 82%-87%. After sorting with heavy medium cyclone and spiral concentrator, the content of titanium and iron oxide reaches 91%-93%. The annual processing of ore is 2.5 million tons, and the ore supply smelting enterprise with a particle size of 38-3.4 mm is also used as a flux (protective agent). Heavy medium cyclone and spiral beneficiation and beneficiation products are given to the sonar smelter rotary kiln for calcination and desulfurization, and then smelted by electric furnace to produce TiO 2 70% to 72% high titanium slag and high quality pig iron. At the same time, part of the pig iron is processed into iron powder. The chemical composition of Canadian hematite, ilmenite ore and Sorrel titanium slag is shown in Table 3, and titanium slag is 90% exported.

Table 3 Canadian Hematite Iron Ore and Sorell Titanium Slag Chemical Composition ω/%

Mineral product

chemical composition

TiO 2

FeO

Fe 2 O 3

Fe (metal)

SiO 2

Al 2 O 3

CaO

MgO

V 2 O 5

MnO

S

P 2 O 5

ore

34.3

27.5

25.2

4.3

3.5

0.9

3.1

0.27

0.16

0.30

0.015

Titanium slag

72.0

12.0

1.5

3.5

4.0

1.2

4.5

0.5

0.2

0.03

0.25

The vanadium-titanium magnetite deposit in the Ural region of Russia has been extensively developed and utilized. The Kycин concentrator has used the magnetic flotation flotation process to produce iron-vanadium concentrate and titanium concentrate. The world's largest vanadium-titanium magnetite ore dressing company is the Katschkenar mining company. The mine has a reserve of 3.5 billion tons. The ore is a vanadium-depleted titanium magnetite with an average of 15% to 17% Fe, 0.43% to 1.88% TiO 2 and 0.13% V 2 O 5 . The concentrator has 3 coarse crushing series, 14 medium and fine crushing series, 29 mineral processing series, processing ore 45 million t/a, producing iron and vanadium concentrate 8 million t/a, and making sinter and pellets. The mine supplies steel and vanadium slag to the smelting plant in the Ural region. Vanadium in the steel production process, through two steelmaking operations, can be integrated with V 2 O 5 16% vanadium slag products. The mine is characterized by low production cost of mining and mineral processing, large scale of production, attention to large-scale and high-efficiency equipment, high labor productivity, low energy consumption, and the renewal period of major process equipment is 8 to 12 years. Pay attention to the comprehensive utilization of waste rock despite the Russian Industrial Production Office. During the recession, energy prices rose, the mine has better economic benefits, and the profit rate has only dropped from 13% to 11.5%. The chemical composition of ore, iron concentrate and tailings is shown in Table 4.

Table 4 Chemical composition of ore, iron concentrate and tailings selected by Kaczarnal Mining Company ω/%

product

chemical composition

Fe

TiO 2

V 2 O 5

FeO

Fe 2 O 3

SiO 2

Al 2 O 3

CaO

MgO

ore

15.9

1.50

0.13

5.5

16.6

47.37

10.08

14.1

8.9

Concentrate (1~15 series)

60.3

0.66

27.2

55.91

5.10

2.62

1.73

2.57

Concentrate (16~29 series)

62.5

28.75

57.33

3.96

2.44

1.35

2.14

Tailings (wet magnetic separation)

6.55

4.2

4.96

46.86

5.90

15.29

13.05

(3) Technological progress and development

The technical progress of vanadium-titanium magnetite beneficiation is mainly reflected in the continuous research and application of new technologies, new processes and updated technical equipment to promote production capacity and product quality.

In the middle of the 20th century, the Sangfu Lake concentrator was put into operation in North America in 1942. In 1950, the mining and utilization of the Aaled Lake mine was utilized. In 1954, the European Otto Mickey Mine Concentrator was put into operation. In 1960, the Norwegian Egson plant was completed and put into operation. Large-scale development and utilization of vanadium-titanium magnetite. The larger-scale development was 30 million t/a in the 1963 Kaczarnal mining company and later developed to 45 million t/a. In 1968, the development of steel, vanadium slag and vanadium products in the Marpoz mine in South Africa was put into operation. In 1970, Panzhihua mining and selection enterprises (design scale of 3.5 million t/a) were completed. Pangang (Group) Co., Ltd. began to use Panzhihua high-titanium iron-vanadium. The concentrate is smelted with vanadium-containing pig iron, vanadium slag and high-quality steel. These enterprises rely on continuous technological advancement to develop and effectively develop and utilize vanadium-titanium magnetite resources with various characteristics.

The treatment of the Mapo spine in South Africa is characterized by pre-screening the ore into 32 to 6 mm and -6 mm products. The two processes are separately treated: the lump ore (32~6 mm) is pre-reduced by the rotary kiln, and is smelted by a submerged arc electric furnace to produce vanadium-rich iron water, which is then subjected to an oxygen blowing vibration tank to obtain vanadium slag. The vanadium slag is cooled and then crushed. Magnetic separation and iron removal to improve vanadium grade, generally vanadium composition is V 2 O 5 25%, SiO 2 16%, Cr 2 O 3 5%, MnO 4%, Al 2 O 3 4%, CaO 3%, MgO 3% The rest are iron oxides and iron; the fine ore (-6mm) is ground to -200 mesh by a wet ball mill to 60%, and then the iron and vanadium concentrate is magnetically selected, mixed with the sodium salt and then fed into the rotary kiln (or multi-layer roasting). The shaft furnace), the calcined product is further fed into the leaching and rotary drying system to obtain flake V 2 O 5 . The basis of this production process was the successful process of producing pig iron and vanadium slag in 1949. The intermediate test was carried out in 1961, and the production was started in 1968. The rotary kiln pretreatment technology was successfully established. The submerged arc furnace was used to refine the technology rich in molten iron. The technology of oxygenation and recovery of vanadium slag in the tank, as well as ore classification and processing technology. The -6mm powder ore roasting leaching mainly solves the grinding system and magnetic separation enrichment technology, sodium oxidizing roasting technology, multi-vanadate leaching and drying technology for the preparation of rotary kiln raw materials.

The development of Kachkanal vanadium-titanium magnetite beneficiation technology is characterized by the use of large-scale mining and transportation equipment for continuous improvement of the process; the processing of low-grade raw ore into iron-vanadium concentrate under high labor productivity; The benefits and strong competitiveness, production capacity continues to expand and develop from 3,000 tons of raw ore processing capacity in 1963 to 45 million t / a in 1988. By 1993, the ore dressing plant had processed 1 billion tons of ore and produced 184 million tons of iron and vanadium concentrate. This expansion of production capacity is mainly due to technological development and the adoption of new technologies and equipment. For example, in 1985, the old equipment was upgraded with high-efficiency new coarse, medium and fine crushing equipment. By 1988, the dry magnetic separation equipment was updated three times, the grinding equipment was updated twice, and the wet magnetic separation equipment and filtration equipment were updated three times. . The company has created a complete set of high-efficiency and low-cost process technologies for the extraction, selection and burning of extremely poor vanadium-titanium magnetite ore.

The geological, mineral processing, smelting and comprehensive utilization research of Panzhihua vanadium-titanium magnetite resource development has been very successful. First, in 1958 and 1964, a large-scale smelting test was carried out to solve the technical problem of smelting high-titanium iron-vanadium concentrate in the blast furnace in the world, and the vanadium-containing pig iron was normally produced. At the same time, the standard vanadium slag is produced from molten iron, and a complete vanadium-titanium magnetite smelting process technology is established. On this basis, the Panzhihua concentrator and steel plant were completed and put into operation in 1970. The high-quality titanium concentrate was sorted out from the iron ore tailings, the primary ilmenite ore dressing technology was established, and the titanium production plant was built. In the long-term production practice and research work, the titanium magnetite ore dressing technology and the ilmenite ore dressing technology have been further improved and improved. Panzhihua vanadium-titanium magnetite beneficiation crushing and screening system, by improving the shape of the broken wall and rolling wall and improving the crushing parameters, the final crushed product -20mm content is increased from 86.77% to 90.16%; using φ2200mm super heavy-duty multi-cylinder hydraulic cone The crusher updates the fine crushed short-head crusher to further reduce the particle size of the crushed product; improving the quality of the grinding medium reduces the unit consumption of the steel ball from the original 0.95kg/t ore to 0.61kg/t ore ; the ball mill adopts hydraulic suspension bearing technology. It can save 5%~7% of electricity consumption; update φ600mm×1800mm magnetic separator with CYT-618 φ750mm×1800mm magnetic separator, the grade of tailings drops by 0.89 percentage points, the recovery rate increases by 2.19 percentage points; the non-uniform magnetic field uses φ1050mm ×3000mm type and φ1050mm×2100mm type magnetic separator are CYT-618 type φ750mm×1800mm magnetic separator. The iron content of tailings can be reduced by 0.2%, the recovery rate is increased by 0.47 percentage points or more; GL-2 type φ600mm spiral is used. The concentrator updates the FLX-1 φ600mm cast iron spiral concentrator to increase the throughput of 3.14 t/set·h and the sorting index. For the tailings transportation, the improved 250PN slurry pump and the impeller, guard plate and sheath made of wear-resistant material Cr 15 Mo 3 alloy are used to solve the wear problem of the pump, and the service life of the spare parts is more than 2500 h; Conveyor pipes and chutes are lined with diabase cast stone materials; research on improving the sorting index of electric sorters and new equipment has made great progress. In recent years, fine-grained ilmenite recovery has also achieved better sorting indicators. The electrowinning tailings recovered the pyroxene in the sputum to obtain a higher purity bismuth product.

Over the years, China has paid great attention to the newly developed research on the utilization of vanadium-titanium magnetite resources, and obtained the results of the ore dressing industry test in the early stage of construction. The reserves of vanadium-titanium magnetite in the Magpie Mountains of Canada are more than 1 billion tons, and other large vanadium-titanium magnetite deposits in North America (including the United States) have been basically proved, and some experimental research work has been done, but they have not been exploited. In order to meet the demand of the vanadium market, South Africa plans to develop a promising mining area in the Brits area.

Third, vanadium-titanium magnetite ore dressing and comprehensive development and utilization of new topics

The development of vanadium-titanium magnetite ore dressing technology has promoted the economic benefits of this mineral resource and promoted the development and changes of itself and related industries. This driving force is mainly technology and economy. Mining development In the overall economic development, the main influencing factor is production costs, and technology is a key factor affecting costs. It is even more important to rely on scientific and technological progress to creatively solve new problems in the mineral processing industry that restrict development.

(1) Establish energy-saving beneficiation technology and process

Adopt high-tech to transform high-energy operation, implement high-energy impact and layer crushing and crushing, reduce the particle size of human grinding, and carry out grinding medium grinding. According to the characteristics of magmatic vanadium-titanium magnetite ore, it is possible to reduce the power consumption of crushing operations by more than 50%.

Creating new separation process of high energy consumption transformation process, application of new materials (e.g., high-performance Nd-Fe-B permanent magnet materials) and high efficiency integration of new technologies, the establishment of a new treatment process vanadium-titanium magnetite. Especially important for the development and utilization of new resources.

(2) Development of technologies to enhance the comprehensive utilization of resources

Broaden the field of mineral processing technology. Develop interdisciplinary technology, improve the recovery of useful element varieties, and recover potential resources that have not yet been utilized to develop a comprehensive and comprehensive utilization of new technologies and technologies for vanadium-titanium magnetite resources to achieve iron, titanium, vanadium, gallium and antimony. Recycling of precious metals, etc.; comprehensive development and utilization of gangue mineral products (tailings); blast furnace slag (including converter or electric furnace slag) containing about 25% V 2 O 5 is a potential resource, and it is necessary to develop new technologies and utilization.

(III) Establishing a mining ecological industrial park - a new concept of mining development

Mining is a resource-based industry and a traditional industry, and is now undergoing a new historical period of reform and modern mining. Its industrial base status still exists, but to establish a new concept of mining development can promote the sustainable development of the mining industry.

The new concept of mining resource development is to establish a mining eco-environment industrial system (mining eco-industrial park) to ensure that the overall goal of promoting economic, social, resource and environmental coordination and sustainable development proposed in China's Agenda 21 is achieved. The carrier community or mining area of ​​the mining industry has built a “safe and comfortable home” - Mining Eco-Environment Industrial Park.

In China's vanadium-titanium magnetite resource development community, a certain scale and management model has been formed, and it is very important to learn from the experience of industrial zones (or mining areas) in modern world developed countries and domestic high-tech development zones (such as Suzhou Industrial Park) to implement environmental management. The system (EMS) will further build a mining eco-industrial park (demonstration area). Based on the backbone enterprises of mineral resources development and processing, a series of community service and production enterprises will be established to deal with solid waste (waste rock, tailings, slag), nitrogen and water in the development of mineral resources, and improve environmental quality and ecological benefits. . Implement land ecological restoration, landscape shaping, and develop agriculture, forestry and tourism to build a “world Taoyuan” community with coordinated development of society, economy, population and environment.

references

1. Zhu Junshi, et al. China vanadium-titanium magnetite ore dressing. Beijing: Mining and Metallurgical Industry Press. 1996.

2, Zhong Han, Yao Fengliang. Metal deposits. Beijing: Geological Publishing House, 1985.

3. Hall J. Contribution of the Republic of South Africa to the extraction of iron and vanadium from titanomagnetite. International Conference on the Development and Utilization of Vanadium-Titanium Magnetite.1989.

4, Zhang Hongfu, Wu Like. Russia Kaqikanal mining joint venture. Foreign metal ore dressing. 1996 (5): 28 ~ 32.

5. Ren Jueshi, et al. Handbook for the Development and Utilization of Industrial Mining Resources. Wuhan: Wuhan University of Technology Press. 1993.

6. Yao Peihui, Wang Kenan, et al. China Iron Mine. Beijing: Geological Publishing House. 1993.

7. Qin Zhen, Lu Zuxiong, et al. Metallogenic characteristics of Panzhihua vanadium-titanium magnetite. International Conference on Development and Utilization of Vanadium-Titanium Magnetite.1989.

8. Zhu Junshi. Beneficiation characteristics of vanadium-titanium magnetite in Panzhihua-Xichang area. Mining Engineering. 1997(1): 20~24.

9. Xu Xinbang. Slon Magnetic Separator Sorting Industrial Test of Pangang Fine Particle Ilmenite. Metal Mine. 1997(1): 17~20.

10, Mao Jianjun, Fan Jianqin, et al. Research on the extraction process of titanium tailings from Panzhihua. Mining and Metallurgy Engineering. 1996(4): 48~52.

11. Cheng Xiwei. Process mineralogy of vanadium-titanium magnetite. Mining and Metallurgy Engineering. 1983(4): 27~32.

12, Dai Huixin, Zhang Zonghua. Research on new technology of fine-grained ilmenite ore dressing. Foreign metal mines. 1998(5): 22~23.

13. Liang Guoqiang, Feng Wenpu. Selection and production process of Panzhihua vanadium-titanium magnetite. International Conference on Development and Utilization of Vanadium-Titanium Magnetite.1989.

14. Yan Zixue, Yang Zhihua, et al. Midi Concentrator. See: China Iron Ore Dressing Production Practice. Nanjing: Nanjing University Press. 1992.237~252.

15. The process of recycling gravel by Sigma. LV. Kaczarnarsk. Dopный Журнзл, 1996: 10-11, 106-108.

16, Zhu Junshi. China's iron ore dressing technology progress and typical process. China Metallurgy. 1993 (3): 81 ~ 86.

17, Zhu Junshi, Zhang Hongfu. Promote new technology to improve the competitiveness of mining enterprises. Steel. 1997.32 (10): 204 ~ 205.

18. Wang Yunmin, Chang Qianfa. Current resource status, utilization status and working direction of iron ore tailings in China. Metal Mine. 1999(1): 1~6.

Aluminum Foil Vacuum Bag

Vacuum Sealer Alumium Foil Bag,Heat Seal Vacuum Alumium Foil Bag,Food Storage Vacuum Sealer Bag,Front Clear Aluminum Foil Vacuum Bag

Shenzhen Lehua Packaging Materials Co., Ltd , https://www.shenzhenlehua.com

Posted on