Method for inhibiting formation of wall-climbing titanium in titanium sponge production process
By adopting a stepped, segmented feeding system in the production of sponge titanium, the problems of uneven quality and equipment corrosion caused by titanium climbing over the wall were solved, achieving efficient production control and environmental protection.
Patent Information
- Application Number
- CN202511104397.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-07
- Publication Date
- 2025-11-07
AI Technical Summary
In the existing sponge titanium production process, the formation of climbing titanium leads to uneven product quality, increases production and equipment maintenance costs, and may cause environmental pollution.
A stepped, segmented feeding system is adopted. By setting key control nodes for the cumulative amount of materials, the reduction reaction rate is precisely controlled, the growth rate of the reaction interface is controlled, the heat fluctuation of the reaction is avoided, and the deposition of titanium on the reactor wall is suppressed.
It effectively inhibits the formation of climbing titanium, improves the quality uniformity of sponge titanium, reduces production costs, extends equipment life, and reduces the risk of environmental pollution.
Smart Images
Figure CN120905545A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of titanium sponge production, in particular to a method for inhibiting the formation of wall-climbing titanium in the production of titanium sponge. BACKGROUND
[0002] The basic process route of preparing titanium sponge by magnesium thermal reduction method is: titanium ore (rutile, titanium slag, or ilmenite) → titanium slag → crude titanium tetrachloride → purified titanium tetrachloride → magnesium reduction distillation → titanium sponge.
[0003] Selecting suitable titanium ore such as rutile, titanium slag, or ilmenite, converting it into crude titanium tetrachloride, and further purifying it to obtain purified titanium tetrachloride. At the same time, prepare metal magnesium as a reducing agent. The magnesium should be easy to purify to prevent its impurities from contaminating the reduced metal, and it should be abundant in resources and have relatively low production cost.
[0004] Use a closed steel reactor. First, put pure metal magnesium into the reactor and fill it with inert gas (such as argon) to prevent the metal magnesium and the products in the subsequent reaction process from being oxidized. Then heat the magnesium to melt it. The melting point of magnesium is about 650°C.
[0005] At the beginning of the reduction, the magnesium liquid surface is fully exposed. When TiCl4 is first added, TiCl4 vapor reacts violently with liquid magnesium, accompanied by the occurrence of gas-phase reactions. However, because the surface temperature of the molten pool is not high at the initial stage, the contact between Mg and TiCl4 is limited to the surface of the magnesium, and the apparent activation energy of the reaction is relatively high, so the reaction rate is generally not high. Before the reaction starts, the magnesium does not infiltrate the iron in the reactor, and the magnesium liquid surface is convex. After the reaction starts, the titanium particles generated rapidly adsorb impurities in the magnesium, some of which adhere to the reactor wall, i.e., wall-climbing, and most of which sink to the bottom of the tank together with MgCl2. The reduction rate is relatively slow during this stage, and about 5% of magnesium is consumed.
[0006] This reduction stage continues on the magnesium liquid surface and lasts for a long time, which is the main stage of the reduction.
[0007] The product after magnesium reduction of TiCl4 is a multiphase system containing Ti, MgCl2, residual Mg, etc. The residual magnesium and MgCl2 are separated by vacuum distillation method, thereby obtaining sponge-like metallic titanium. After melting, the distillation condensate discharges magnesium chloride, and the remaining magnesium can continue to participate in the magnesium reduction process in the production process of the magnesium thermal method. In addition, the byproduct magnesium chloride produced in the reduction reaction using metal magnesium as a reducing agent is recovered by electrolysis to obtain magnesium and chlorine gas. The magnesium continues to participate in the reduction reaction, and the chlorine gas is transported to the chlorination workshop for recycling, achieving the recycling of magnesium and chlorine gas.
[0008] Climbing wall titanium belongs to a kind of skin titanium, which contains more impurities. The chlorine content in climbing wall titanium is relatively high, and chlorine impurities are widely distributed in sponge titanium. As the production of the product proceeds, chlorine will accumulate in the skin and titanium cap, which will affect the quality uniformity of sponge titanium. At the same time, the oxygen and nitrogen content at the climbing wall may also be higher. The oxygen and nitrogen brought in by the refined titanium tetrachloride raw material and the long-time air intake will significantly increase the oxygen and nitrogen content of the skin under the condition of slight air intake. Moreover, affected by the wall material, the carbon impurity element content at the climbing wall also has a high possibility. The increase of these impurity contents will eventually affect the mechanical properties of the processed titanium products.
[0009] Climbing wall titanium is classified as off-grade sponge titanium. Compared with normal sponge titanium products, off-grade sponge titanium has obvious defects, such as obvious dark yellow and bright yellow oxidation marks, chloride residues, and residues. This kind of off-grade sponge titanium has a lower value on the market. If the climbing wall titanium is not handled well, it will reduce the overall value of the product. And from the production point of view, in order to obtain qualified sponge titanium products, additional processes are needed to handle the climbing wall titanium, such as separating it from the qualified part, further impurity removal, etc., which will undoubtedly increase the production cost and production cycle.
[0010] Climbing wall titanium adheres to the reactor wall, which may affect the normal operation and service life of the reactor. In the subsequent production process, climbing wall titanium may fall off into the reaction system, interfere with the normal progress of the reaction, and even cause unstable product quality. In addition, impurities such as chlorine contained in climbing wall titanium may cause corrosion to production equipment under certain conditions, increasing equipment maintenance costs. Moreover, during the handling of climbing wall titanium, if not handled properly, the impurities in it may be released into the environment, causing pollution to the surrounding environment.
[0011] On June 4, 2025, a search was conducted in the China Patent Publication Database with "Sponge Titanium and Climbing Wall and Segmentation and Feeding" as the abstract keyword, and the synonym expansion option was checked. No relevant literature was found.
[0012] On June 4, 2025, an abstract search was conducted on China's CNKI with "Sponge Titanium and Climbing Wall and Segmentation and Feeding", and no relevant literature was found.
[0013] On June 4, 2025, a search was conducted on the United States Patent and Trademark Office website with "Sponge Titanium with Climbing Wall with Segmentation with Feeding", and no relevant literature was found; the search website is https: / / ppubs.uspto.gov / pubwebapp / .
[0014] No relevant documents were found by searching on https: / / patentscope2.wipo.int / on June 04, 2025 with "Sponge Titanium and Climbing Wall and Segmentation and Feeding".
[0015] No relevant documents were found by searching on https: / / www.j-platpat.inpit.go.jp / of Japan Patent Office on June 04, 2025 with "Sponge Titanium and Climbing Wall and Segmentation and Feeding".
[0016] Completely different from the concept of this patent. SUMMARY
[0017] The purpose of the invention is to provide a method for inhibiting the formation of climbing wall titanium in the production process of sponge titanium with better effect, and the specific purposes are the multiple substantial technical effects in the specific implementation part.
[0018] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:
[0019] The method for inhibiting the formation of climbing wall titanium in the production process of sponge titanium is characterized in that,
[0020] Pre-control before feeding: 0-25000kg stage;
[0021] From 0 to 500-600kg / h normally, ensure that the reaction system reaches the thermodynamic equilibrium state, and establish a stable foundation for subsequent process adjustment;
[0022] Stepwise speed reduction control: 25000kg to the end of reduction; Establish four-stage gradient material reduction system:
[0023] The four-stage gradient material reduction system is:
[0024] First-stage speed reduction: set a stable material speed between 400-500kg / h, and the material accumulates to 20000-25000kg stage;
[0025] Second-stage speed reduction: set a stable material speed between 300-400kg / h, and the material accumulates to 25000-30000kg stage;
[0026] Third-stage speed reduction: set a stable material speed between 200-300kg / h, and the material accumulates to 30000-35000kg stage;
[0027] End section maintenance: set stable material speed between 200-300 kg / h until the reduction reaction is completely terminated.
[0028] The further technical solution of the present application is to realize the discrete and accurate control of the reduction reaction rate by setting the key control node of the material accumulation.
[0029] The further technical solution of the present application is to stabilize the reaction interface growth rate after the stepwise speed reduction, and to stabilize the gas-solid interface moving speed in the optimal range of 0.8-1.2 mm / min.
[0030] The further technical solution of the present application is to maintain the thermodynamic equilibrium, which is used to avoid the reaction heat fluctuation caused by continuous speed reduction, and the temperature change range ΔT≤15℃ of the reaction heat fluctuation can effectively inhibit the titanium vapor deposition caused by local overheating.
[0031] The present application adopting the above technical solution has the following beneficial effects compared with the prior art: the present process proposes a process improvement scheme by optimizing the feeding system in the reduction stage to solve the problem of wall climbing titanium in the process of preparing titanium sponge by magnesium reduction method. The core improvement point is to adjust the traditional continuous ramp-down mode to multi-stage stepwise segmented control, to effectively inhibit the abnormal deposition of titanium on the reactor wall by accurately controlling the reaction interface growth rate. BRIEF DESCRIPTION OF DRAWINGS
[0032] In order to further illustrate the present application, the following further illustrates the present application in combination with the drawings:
[0033] Figure 1 The flow chart of the feeding control process in the reduction stage of titanium sponge production. DETAILED DESCRIPTION
[0034] The present application is further illustrated in combination with the drawings and specific embodiments, and it should be understood that the following specific embodiments are only used to illustrate the present application and not to limit the scope of the present application. The process points are:
[0035] 1. Pre-feeding control (0-25000 kg stage)
[0036] From 0 to 500-600 kg / h, ensure that the reaction system reaches the thermodynamic equilibrium state, and establish a stable foundation for subsequent process adjustment.
[0037] 2. Stepwise speed reduction control (25000 kg to reduction end), establish four-stage gradient feeding system:
[0038] First-stage speed reduction: set stable speed between 400-500 kg / h (material accumulation 20000-25000 kg stage)
[0039] Secondly, the speed is reduced: 300-400 kg / h is set to stabilize the material speed (the cumulative material is 25000-30000 kg)
[0040] Thirdly, the speed is reduced: 200-300 kg / h is set to stabilize the material speed (the cumulative material is 30000-35000 kg)
[0041] The final stage is maintained: 200-300 kg / h is set to stabilize the material speed until the reduction reaction is completely terminated.
[0042] 3. Process advantage analysis:
[0043] (1) Stage control mechanism: By setting the key control nodes of the cumulative material, the discrete and accurate control of the reduction reaction rate is realized, and the process control precision is improved by about 40% compared with the traditional continuous speed reduction mode;
[0044] (2) Interface growth control: The stepwise speed reduction can smoothly transition the reaction interface growth rate, and the gas-solid interface moving speed is stabilized in the optimal interval of 0.8-1.2 mm / min;
[0045] (3) Thermodynamic equilibrium maintenance: The discrete adjustment scheme can avoid the reaction heat fluctuation (ΔT≤15℃) caused by continuous speed reduction, and effectively suppresses the titanium gas deposition caused by local overheating;
[0046] (4) Production efficiency improvement: Under the premise of ensuring product quality (titanium purity≥99.7%), the single furnace titanium production amount can be reduced to less than 60% of the traditional process.
[0047] (5) The present scheme establishes the quantitative correspondence between the cumulative material and the feeding rate, realizes the controllable and gradual adjustment of the reduction process, and provides a new technical path for the quality control and process optimization of sponge titanium production.
[0048] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of protection.
Claims
1. A method for inhibiting the formation of wall-climbing titanium in a titanium sponge production process, characterized in that, Pre-feeding stage control: 0-25000 kg stage; Normal climb from 0 to 500-600 kg / h, ensure that the reaction system reaches a state of thermodynamic equilibrium, and establish a stable foundation for subsequent process adjustment; Stepwise speed reduction control: 25000 kg to the end of reduction; Establish a four-stage gradient reduction system: Four-stage gradient reduction system: First-stage speed reduction: Set a stable speed of 400-500 kg / h, and accumulate 20000-25000 kg of material in this stage; Second-stage speed reduction: Set a stable speed of 300-400 kg / h, and accumulate 25000-30000 kg of material in this stage; Third-stage speed reduction: Set a stable speed of 200-300 kg / h, and accumulate 30000-35000 kg of material in this stage; Final stage maintenance: Set a stable speed of 200-300 kg / h until the reduction reaction is completely terminated.
2. The method for suppressing formation of wall-climbing titanium in the production of titanium sponge according to claim 1, characterized by, The phased control mechanism realizes discrete and precise control of the reduction reaction rate by setting key control nodes for material accumulation.
3. The method for inhibiting formation of wall-climbing titanium in the production of titanium sponge according to claim 1, characterized in that, After the stepwise speed reduction, the growth rate of the reaction interface is smoothly transitioned, and the gas-solid interface moving speed is stabilized in the optimized range of 0.8-1.2 mm / min.
4. The method for inhibiting formation of wall-climbing titanium in the production of titanium sponge according to claim 1, characterized in that, The method maintains thermodynamic equilibrium to avoid reaction heat fluctuations caused by continuous speed reduction, and the temperature change range ΔT of reaction heat fluctuations is ≤15 ℃, which can effectively inhibit titanium gas deposition caused by local overheating.