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Direct Reduction of Titanium Dioxide by Pengfei Rotary Kiln

Date: 2018-06-17 17:48
Jangsu Pengfei; Rotary kiln; Nonferrous metal smelting; Calendering processing industry; Sintering furnace; Industrial furnace; Metallurgical nickel, iron, aluminum, copper, zinc, tin, tungsten, chromium, file and other metals in rotary kiln for smelting equipment; Ore, concentrate sintering, roasting; Tianqi lithium industry; Dingsheng lithium industry; Jiangxi feng lithium industry .
Jiangsu Pengfei Group co., Ltd., specializes in the production of "Pengfei" rotary kiln ( rotary kiln, sintering furnace, industrial furnaces, kilns), specification: Φ3.2× 52 m, Φ3.5×54m, Φ4.0×60m, Φ4.3×64m, Φ4.8×74m, Φ5.0×78m, has been widely used in cement, metallurgy, chemical, environmental protection and other industries. Pengfei rotary kiln in non-ferrous metal smelting and rolling processing industry of non-ferrous and ferrous metallurgy iron, aluminum, copper, zinc, tin, nickel, tungsten, chromium, file of metal in rotary kiln for smelting equipment, to sintering ore, ore concentrate, intermediate, and roasting. The application of rotary kiln in titanium dioxide direct reduction is recently realized. The main customers include: Anhui Tongling Annada, Ningbo Xinfu, Shanghai Dongtai, Yunnan Longyuan, Hainan Fuda, Jiangsu Jinpu Group, Super Color Titanium Technology, South Africa NITTAL Company, etc.
Titanium dioxide is a very important raw material in industrial production, and is widely used in coatings, plastics, paper, printing inks, chemical fiber, rubber, cosmetics, ceramics, enamel, electronics, food and pharmaceutical industries. At present, DuPont, Millennium and Tronox have mastered the advanced titanium dioxide chlorination production technology. The use of traditional sulfuric acid method to produce titanium dioxide also requires a large amount of proprietary technology, know-how and operational experience in actual production. The technology accumulation and technological innovation capabilities of enterprises puts forward high requirements for the enterprises who are going to enter into this industry. Titanium dioxide industry is a relatively technology-intensive and capital intensive industry, and for building a new plant using sulfuric acid process. it is generally estimated that the construction funds will reach 120 million or so to reach the economic scale. And to build a plant with the same scale using chlorination process, more capital is needed. Due to technical accumulation and operational experience has a crucial impact on normal production, there is still a long period of time to reach the standard and output of production after construction and putting into operation, thus it puts forward high requirements for operating funds.
In the case of overseas blockade of chlorination technology, incomplete control in the country, and lack of promotion and application, the investment in sulfuric acid titanium dioxide, if the product fails to meet international standards, waste acid and ferrous iron cannot be used comprehensively, and environmental protection cannot meet discharge standards, the national industry policy restricts the construction of new projects and prohibits investment. Judging from the current situation, the peak demand for titanium dioxide in September and October is coming to an end. The price of titanium dioxide is unlikely to increase again during the year. Domestic titanium dioxide prices have been leveled at the current level of 1.3 to 14 thousand tons per ton. The global titanium dioxide production capacity has shifted to the domestic market, so the long-term picture of titanium dioxide export remains constructive.
Rotary kiln is more and more widely used. In aluminum production, it is calcined to alumina. In iron production, it produces pellets for blast furnace ironmaking, and using it to do direct reduction of iron ore.  For chlorination volatilization roasting method, it is used to extract the tin and lead, etc. In the process of beneficiation, it is used for the magnetic roasting of lean iron ore so that the original weak magnetism of the ore changed to strong magnetism, which is good for magnetic separation. In chemical industry, rotary kiln is used for baking soda, calcining phosphate fertilizer, barium sulfide, titanium dioxide, etc. It has the advantages of using low-grade phosphorite, which is widely promoted. It is used for calcining clay, limestone and for slag drying. In the production of refractory material, rotary kiln is used to calcinate raw material, so that its dimension is stable and the strength increases, and then the processing takes shape. In environmental protection, the use of cement kilns is to incinerate hazardous wastes, rubbish and realizes unharmful waste discharging, and waste is used as fuel to save pulverized coal and to recycle waste.
The device consists of cylinder, supporting device, thrust roller device, transmission device, moving kiln head, kiln tail sealing device, burning device and other parts. The rotary kiln has simple structure, reliable operation, easy controlling production process, etc. Through technology innovation, "Pengfei" rotary kiln calcining system equipments uses domestic advanced technology such as the most advanced hydraulic thrust roller device, adopting metering piston pump with high measuring accuracy, high precision speed control valve and contact-type graphite block sealing device. Kiln head can use industrial television to watch the fire, process flow simulation screen. And for calcining zone, it uses infrared scanners to reflect calcination conditions of calcining zone directly on the computer. The use of these new technologies has strong intuitive sense, easy operation and reliable usage. We have stabilized the thermal system, improved the equipment operation rate, and compared with the equipment of same specification, the output increased by 10% and the heat consumption decreased by 15%.
  With the shrinking of foreign production capacity and the improvement of the domestic titanium dioxide quality, the long-term good trend of China's titanium dioxide exports will not change. The "TR52 Disposal Agreement" signed between the listed titanium dioxide leader HENAN BILLIONS CHEMICALS and the international titanium dioxide giant Huntsman also reflects the global transfer of titanium dioxide production capacity to China. Titanium dioxide market will continue. Since the beginning of this year, international titanium dioxide giants have raised their prices one after another. At the same time, domestic titanium dioxide leaders have also raised titanium dioxide prices six times this year. With the arrival of the peak season, titanium dioxide prices will continue, especially with the release of real estate policies in China, real estate sales market has entered a new round of warming cycle, and the release of housing demand will directly stimulate the growth of titanium dioxide consumption in China.  At the same time, the titanium dioxide industry has long-term environmental restrictions of strict policy, and environmental protection will accelerate the integration of production capacity in the industry and promote the concentration of competitive advantages to leading companies. At present, the total production capacity of titanium dioxide projects under construction in the country is total 1.31 million tons and will reach 4.2 million tons in 2018. The main domestic titanium dioxide projects are
Producer Capacity (10,000 tons) Process
Dupont Dongying 20 Chlorination
Luohe City Xingmao Titanium Industry Co.,Ltd 20 Chlorination
Jinan Yuxing Chemical Co.Ltd 20 Sulfuric acid
Guangxi Jinmao Titanium Co., Ltd. 10 Sulfuric acid
Wuzhou jiayuan industrial co. Ltd. 10 Sulfuric acid
Guangxi CAVA Titanium Industry Co. Ltd. 10 Sulfuric acid
Sichuan Lomon Titanium Industry Co., Ltd. 10 Chlorination
Jiangsu GPR0 Group Co., Ltd. 8 Sulfuric acid
Henan Billions Chemicals Co., Ltd. 6 Chlorination
Yunan Xinli Nonferrous Metals Co., Ltd. 6 Chlorination
Shandong Doguide Group Co., Ltd. 6 Chlorination
Hainan Fuda Titanium Co., Ltd. 5 Sulfuric acid
Shanghai Liangjang Titanium White Product Co., Ltd. 5 Sulfuric acid
Preparation and Study of Titanium Dioxide Reduction Graphene
Direct metal titanium production from titanium dioxide
Titanium dioxide has an important role in the photocatalytic degradation of organic matter and photoelectric conversion due to its excellent photoresponse performance. At the same time, the diversity of its crystal structure and microscopic morphology makes it extremely variably and scientifically researchable. Researching the new morphology of titanium dioxide, discovering the new crystal structure of titanium dioxide, and improving the photocatalytic performance of titanium dioxide by doping and compounding have become the hotspot and focus of current research.
Through the combination of precipitation method and hydrothermal method, the conditions for the formation of TiO2 nanosheets were explored, and the effects of various reaction conditions on product performance were systematically discussed. In order to further improve the photocatalytic performance of the product, the obtained product and graphene oxide were reduced and composited by a hydrothermal method to prepare a titania/graphene oxide composite material. The influence of the reaction conditions on the photocatalytic performance of the product and the role of graphene  oxidation and reducing agent in the composite process were discussed, and analyzed and explored the main action principle of reducing graphene oxide to improve photocatalytic performance.
    (1) Ti (OH)4 obtained after hydrolysis of titanium sulfate is a precursor, and NaOH solution is a reaction medium. A layer with a good lamellar structure is prepared by controlling the concentration of NaOH solution and the hydrothermal reaction time and hydrothermal reaction temperature. Amorphous compounds were observed by TEM. The effects of reaction time and reaction temperature on the morphology of the products were investigated. In order to obtain reaction products with photocatalytic properties, anatase TiO2 was prepared by hydrogen ion exchange combined with high temperature calcination. The effects of calcination temperature and calcination time on the morphology and photocatalytic properties of the product were analyzed. The experiment shows that the concentration of NaOH solution affects the morphology of the product, and the hydrothermal reaction temperature and the hydrothermal reaction time affect the thickness and size of the TiO2 nanoplatelets at 150°C, and the product obtained by the hydrothermal reaction in a 6-mol/L NaOH solution for 96 hours has the most Good slice structure. The calcination temperature and calcination time mainly affect the size of the crystal and the number of crystal defects. Our study shows that the product obtained after calcination at 400 °C for 3 h has the best photocatalytic effect.
(2) In order to prepare a titania/graphene oxide composite, we mixed the dry product after ion exchange with the graphene solution as a precursor, hydrothermally compounded under the condition of citric acid as a reducing agent, and then proceeded under the protection of N2 Calcined. In this experiment, we studied the effect of precursor to graphene ratio, acidity of the reducing agent, hydrothermal reaction time, and hydrothermal reaction temperature on the morphology and photocatalytic properties of the product. The experimental results show that the photocatalytic performance of titanium dioxide/graphene oxide composites is more than 20% higher than that of pure titanium dioxide, and the photocatalytic effect is best when the mass of graphene oxide is 1% of the precursor mass. The optimal reaction conditions were hydrothermal reaction at 80 °C for 8 h in a citric acid solution with a concentration of 0.1 g/ml.
(3) Through the above experiments, we have analyzed the effect of reduced graphene oxide: the reduced combination of graphene oxide and titanium dioxide changes the crystal structure on the one hand, and the rutile phase appears in the product after calcination at 400°C. A mixed crystal structure is formed to improve the photocatalytic performance, and on the other hand, the morphology of the composite product is changed, and the regular structure of the sheet is transformed into a rod-like structure with a rough surface, so that the specific surface area of the product is greatly increased and the adsorption is enhanced. Performance and photocatalytic performance; In addition, the addition of reduced graphene oxide increases the electrical conductivity of the product, promotes the separation of photogenerated electron-hole pairs, and enhances the lifetime of photogenerated electron-hole pairs, greatly improving the redox reaction efficiency.