阅读说明：本技术 四氯化钛生产用复合氯化炉 (Composite chlorination furnace for titanium tetrachloride production ) 是由 王雪峰 刘春江 李晨光 于 2021-10-23 设计创作，主要内容包括：本发明公开了一种四氯化钛生产用复合氯化炉,涉及氯化炉技术领域。四氯化钛生产用复合氯化炉,包括沸腾氯化段和熔盐氯化段；沸腾氯化段与熔盐氯化段之间固定有气体分配器；沸腾氯化段侧壁设置有第一混合料进口和排料口,排料口与熔盐氯化段连通；熔盐氯化段设置有第一氯气进口和第二混合料进口,熔盐氯化段的中部设置有熔盐排放口,熔盐氯化段的下部固定有电极,熔盐氯化段的下部设置有第二氯气进口,熔盐氯化段的底部设置有熔盐排净口。本装置通过侧排渣将沸腾段产生的金属氯化物排到熔盐氯化段中,定期排放处理,通过沸腾段底排炉料、熔盐段回收炉料和氧化返回氯气夹带TiO-(2)的回收,使钛回收率得到较大的提升。(The invention discloses a composite chlorination furnace for titanium tetrachloride production, and relates to the technical field of chlorination furnaces. The composite chlorination furnace for producing titanium tetrachloride comprises a boiling chlorination section and a molten salt chlorination section; a gas distributor is fixed between the boiling chlorination section and the molten salt chlorination section; a first mixture inlet and a first mixture outlet are formed in the side wall of the boiling chlorination section, and the first mixture outlet is communicated with the molten salt chlorination section; the fused salt chlorination section is provided with a first chlorine inlet and a second mixture inlet, the middle of the fused salt chlorination section is provided with a fused salt discharge port, the lower part of the fused salt chlorination section is fixed with an electrode, the lower part of the fused salt chlorination section is provided with a second chlorine inlet, and the bottom of the fused salt chlorination section is provided with a fused salt discharge port. The device discharges metal chloride generated in the boiling section into the molten salt chlorination section through side slag discharge, periodically discharges and processes, and returns chlorine gas through bottom discharge of furnace charge in the boiling section, recovery of furnace charge in the molten salt section and oxidation and entrainment of TiO 2 The recovery rate of titanium is greatly improved.)

1. A composite chlorination furnace for producing titanium tetrachloride comprises a boiling chlorination section and a molten salt chlorination section; it is characterized in that the preparation method is characterized in that,

a gas distributor is fixed between the boiling chlorination section and the molten salt chlorination section;

a first mixture inlet and a discharge outlet are formed in the side wall of the boiling chlorination section, and the discharge outlet is communicated with the molten salt chlorination section through a pipeline;

the lateral wall of fused salt chlorination section is provided with first chlorine import and the import of second mixture, and the middle part of fused salt chlorination section is provided with the fused salt discharge port, and the lower part of fused salt chlorination section is fixed with the electrode, and the lower part lateral wall of fused salt chlorination section is provided with the import of second chlorine, and the bottom of fused salt chlorination section is provided with fused salt drain-off mouth.

2. The complex chlorination furnace for producing titanium tetrachloride according to claim 1, wherein a gas exhaust port is provided at the top of the boiling chlorination stage.

3. The complex chlorination furnace for producing titanium tetrachloride according to claim 1, wherein a discharge port of the boiling chlorination section is connected with a second mixture inlet of the molten salt chlorination section through a pipeline.

4. The composite chlorination furnace for producing titanium tetrachloride according to claim 1, wherein the first chlorine inlet is connected with a first chlorine pipe, the second chlorine inlet is connected with a second chlorine pipe, and the first chlorine pipe and the second chlorine pipe are connected through a pipeline.

5. The complex chlorination furnace for producing titanium tetrachloride according to claim 4, wherein the first and second chlorine pipes are provided with a pressure sensor and a control valve, respectively.

Technical Field

The invention relates to the technical field of chlorination furnaces, in particular to a composite chlorination furnace for producing titanium tetrachloride.

Background

Titanium dioxide is a white inorganic pigment, is the white pigment with the best performance in the world at present, is an inorganic chemical product second to synthetic ammonia and phosphoric acid and sold in the third rank in the world, and is widely applied to the industries of coatings, plastics, papermaking, printing ink and the like. Titanium dioxide is the most important one of titanium products, more than 90% of titanium ores are used for producing the titanium dioxide in the world, the industrial production of the titanium dioxide comprises a chlorination process and a sulfuric acid process, the chlorination process titanium dioxide product has good quality and stable performance, does not basically cause pollution to the environment, is the mainstream technology of the international titanium dioxide production at present, and nearly 75% of the titanium dioxide in the world (excluding China) is produced by the chlorination process.

One of the key processes for titanium dioxide by chlorination is TiCl₄Production of TiCl, the present industrial production₄The method mainly comprises two processes of boiling chlorination and molten salt chlorination, but has certain technical difficulties which are difficult to break through, and mainly comprises the following steps: on one hand, in the boiling chlorination process, along with the collision and friction between materials and the reaction, the particle size of the materials is gradually reduced, and along with the tail gas, the recovery rate of titanium is reduced; on the other hand, due to the limitation of reaction parameters and materials, the boiling chlorination is not suitable for most domestic titanium resources (mainly high-calcium magnesium titanium resources), so that the resource advantages cannot be embodied. Due to the limitation of the structural form of the molten salt chlorination, the capacity cannot be greatly improved; meanwhile, the high-temperature volatile salt is difficult to recover and has adverse effect on the subsequent process; third, molten salt chlorination is more difficult to handle than boiling chlorination.

Disclosure of Invention

In order to solve the technical problem, the invention provides a composite chlorination furnace for producing titanium tetrachloride, which carries TiO in chlorine gas returned by boiling section bottom discharge furnace charge, molten salt section recovery furnace charge and oxidation₂The recovery rate of titanium is improved.

In order to realize the technical purpose, the invention adopts the following scheme: the composite chlorination furnace for producing titanium tetrachloride comprises a boiling chlorination section and a molten salt chlorination section; a gas distributor is fixed between the boiling chlorination section and the molten salt chlorination section; a first mixture inlet and a discharge outlet are formed in the side wall of the boiling chlorination section, and the discharge outlet is communicated with the molten salt chlorination section through a pipeline; the lateral wall of fused salt chlorination section is provided with first chlorine import and the import of second mixture, and the middle part of fused salt chlorination section is provided with the fused salt discharge port, and the lower part of fused salt chlorination section is fixed with the electrode, and the lower part lateral wall of fused salt chlorination section is provided with the import of second chlorine, and the bottom of fused salt chlorination section is provided with fused salt drain-off mouth.

Compared with the prior art, the invention has the beneficial effects that: the composite chlorination furnace with the combination of the slag-discharging boiling chlorination section and the molten salt chlorination section of the device has the advantages that the high-calcium magnesium titanium raw material is reacted in the boiling chlorination section, and calcium and magnesium are reacted to generate CaCl₂、MgCl₂The titanium is enriched in a boiling bed, and is discharged into a molten salt chlorination section through side slag discharge, and is periodically discharged and treated, so that a beneficial solution is provided for comprehensive utilization of high-calcium magnesium titanium resources and improvement of resource added value in China, and the problem of capacity improvement is well solved; the TiO entrained chlorine is returned by the bottom discharge furnace burden of the boiling section, the recovery furnace burden of the molten salt section and the oxidation₂The recovery rate of titanium is greatly improved.

The preferred scheme of the invention is as follows:

the top of the boiling chlorination section is provided with an exhaust port.

The discharge gate of boiling chlorination section links to each other through the second mixture import of pipeline with fused salt chlorination section, discharges the slay of boiling chlorination section to fused salt chlorination section and carries out secondary chlorination reaction, improves the recovery of titanium dioxide.

The first chlorine inlet is connected with the first chlorine pipe, the second chlorine inlet is connected with the second chlorine pipe, and the first chlorine pipe and the second chlorine pipe are connected through a pipeline.

The first and second chlorine pipes are respectively provided with a pressure sensor and a control valve.

Drawings

FIG. 1 is a schematic structural view of a composite chlorination furnace for producing titanium tetrachloride according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a gas distributor according to an embodiment of the present invention;

labeled as: 1. an exhaust port; 2. a first mixture inlet; 3. a first chlorine pipe; 4. a second chlorine pipe; 5. a molten salt discharge port; 6. an electrode; 7. a discharge outlet; 8. a molten salt discharge port; 9. a gas distributor; 91. a cylindrical member; 92. a breather pipe; 93. a pipe cap; 94. air holes; 10. and a second mixture inlet.

Detailed Description

The present invention will be described in detail with reference to the following embodiments in order to fully understand the objects, features and effects of the invention, but the present invention is not limited thereto.

Referring to fig. 1 and 2, the complex chlorination furnace for producing titanium tetrachloride according to the present invention comprises a boiling chlorination section and a molten salt chlorination section, wherein the boiling chlorination section is an upper portion of the complex chlorination furnace, the molten salt chlorination section is located at a lower portion of the complex chlorination furnace, and a gas distributor 9 is disposed between a lower end of the boiling chlorination section and an upper end of the molten salt chlorination section. The gas distributor 9 is a cylindrical member 91 cast from a refractory casting material, in which uniformly distributed ventilation pipes 92 are embedded. The material of the vent pipe 92 is nickel-based alloy pipe, SiC pipe and Al₂O₃One type of ceramic tube. The bottom end of the breather pipe 92 is flush with the lower surface of the cylindrical member 91; the upper end of the vent pipe 92 is communicated with the upper surface of the cylindrical castable component, and the side wall of the vent pipe 92 higher than the upper surface of the cylindrical castable component 91 is uniformly provided with air holes 94, the number of the air holes is not less than 8, and the aperture is 2-4 mm. An umbrella-shaped pipe cap 93 is fixed at the top end of the breather pipe 92 to prevent solid materials from blocking the breather pipe 92, and the material of the pipe cap 93 is the same as that of the breather pipe 92. The diameter of the vent tube 92 is typically 15-30mm, most preferably 25 mm.

The top of the boiling chlorination section is a furnace top, the furnace top is provided with an exhaust port 1, the exhaust port 1 directly enters an atomizer, and TiCl generated by the reaction is reacted₄The mixed gas is directly fed into the atomizer. The furnace top is also provided with a plurality of thermocouples and pressure sensors. Boiling chlorination section lateral wall is provided with a plurality of first mixture import 2 and bin outlet 7, and first mixture pipe is connected to bin outlet 7, first mixture pipe and fused salt chlorination section intercommunication.

The side wall of the upper part of the molten salt chlorination section is provided with a first chlorine inlet, the first chlorine inlet is connected with a first chlorine pipe 3, a pressure sensor and a control valve (P represents the pressure sensor, M represents the control valve, and T represents a thermocouple in the figure 1) are sequentially arranged on the first chlorine pipe 3 according to the gas flowing direction, and the first chlorine pipe 3 conveys fresh chlorine to the molten salt chlorination section. The lower part lateral wall of fused salt chlorination section is provided with the second chlorine import, and second chlorine import connection second chlorine pipe 4 has set gradually control valve and pressure sensor on the second chlorine pipe 4 according to the gas flow direction, and second chlorine pipe 4 carries the chlorine that the oxidation returns to the fused salt chlorination section. The first chlorine pipe 3 and the second chlorine pipe 4 are connected through a pipeline, and a control valve is arranged on the pipeline.

The side wall of the middle upper part of the fused salt chlorination section is also provided with a second mixture inlet 10, the second mixture inlet 10 is connected with a second mixture pipe, the first mixture pipe is connected with the middle part of the second mixture pipe, and the first mixture pipe and the second mixture pipe are respectively provided with a control valve. A molten salt discharge port 8 is formed in the side wall of the molten salt chlorination section below the second mixture inlet 10, an electrode 6 and a thermocouple are fixed to the side wall of the lower portion of the molten salt chlorination section, and a molten salt discharge port 5 is formed in the bottom of the molten salt chlorination section.

The furnace body and the furnace top of the composite chlorination furnace are both composed of a shell and a lining, the shell is a steel shell, and the lining is made of refractory materials.

In the using process of the device, mixed materials (the mass ratio of the high titanium slag to the calcined petroleum coke is 3: 1) pass through N at a first mixture inlet 2₂And blowing the mixed material into a boiling chlorination section of the composite chlorination furnace. The mix may also be added to the molten salt chlorination stage by screwing through the second mix inlet 10 at the start of the start-up.

In the operation process of the composite chlorination furnace, the discharge opening 7 of the boiling chlorination section is opened periodically or according to the analysis and test result, and the furnace charge slag generated in the boiling reaction passes through N₂And blowing into a molten salt chlorination section.

The blowing is effected by simple pneumatic conveying, N being initially switched on₂Valve M₁Then opening a molten salt section feeding port feeding valve M₃Finally, a discharge valve M of the bottom discharge furnace burden of the boiling section is opened₂And then through N₂And spraying and blowing the bottom grate furnace charge into a molten salt section of the composite chlorination furnace. Thereby realizing the direct recovery of the bottom discharge furnace burden of the boiling chlorination section and improving the recovery rate of titanium.

The mixed gas after the reaction in the molten salt chlorination section enters a boiling section through a gas distributor 9 of the composite chlorination furnace, and excessive Cl is contained in the molten salt chlorination section₂Further carrying out chlorination reaction with titanium-rich material to produce TiCl₄And metal chlorinationThus realizing the saving and recycling of resources.

In the device, two chlorine flows enter a molten salt chlorination section of the composite chlorination furnace, and Cl is newly added₂Introducing the chlorine into the composite chlorination furnace from the position above the molten salt liquid level, entering a boiling chlorination section through a gas distributor 9, and realizing the addition of new Cl from subsequent process parameters₂Flow regulation of (2). Returned Cl from the Oxidation Process₂Enters a molten salt chlorination section of the composite chlorination furnace through the position below the molten salt liquid level, and reacts with the high titanium slag to generate TiCl under the reduction action of calcined petroleum coke₄While returning Cl₂In-band TiO₂Is intercepted by the fused salt and then is recovered.

Excess Cl in the molten salt stage of the invention₂TiCl formed by the reaction₄The molten salt mixed gas and the like enter a boiling chlorination section of the composite chlorination furnace for further reaction to prepare TiCl₄Thereby improving the utilization rate of the reaction.

Due to technical restriction, the domestic chlorination furnace only can exist in the form of a single fused salt chlorination furnace or a boiling chlorination furnace, the invention provides a fused salt and boiling composite chlorination furnace, and the composite chlorination furnace realizes large chlorination of domestic high-calcium magnesium titanium resources; meanwhile, the recovery of the furnace burden of the bottom row, the recovery of the dust collecting slag material and the recovery of TiO2 carried in the chlorine gas returned by oxidation improve the recovery rate of titanium; through the secondary reaction of the molten salt reaction tail gas, the operation of a subsequent system is simpler, and the labor intensity is greatly reduced.

Finally, it is noted that: the above-mentioned list is only the preferred embodiment of the present invention, and naturally those skilled in the art can make modifications and variations to the present invention, which should be considered as the protection scope of the present invention provided they are within the scope of the claims of the present invention and their equivalents.