Learn about sponge titanium in one article

Titanium is a silver-white transition metal with high melting point, high specific strength, good biocompatibility, and strong corrosion resistance.
It is currently widely used in aerospace, defense and military industry, medical biology, petrochemical and other fields
.
China's titanium resources are very rich, and the reserves rank first in the world, but the production capacity of
sponge titanium is relatively weak, which is far from meeting the needs of the country's economic development .
Titanium sponge is elemental titanium, typically as a light gray particles or spongy titanium is the basic raw material, the titanium powder and other titanium products, the ilmenite ore into titanium tetrachloride with magnesium metal reacted to obtain a spongy Porous "sponge titanium"
.
Sponge titanium is widely used in chemical, petroleum, light industry, metallurgy, textile, construction, medical, sports, daily production and other fields
.
Overview of the development of China's titanium sponge industry.
The world has seven countries including the United States, Russia, China, Japan, Ukraine, Kazakhstan and India
.
At the beginning of the 21st century, with the rapid development of China's economy, China's titanium industry has risen rapidly, breaking the long-standing situation of Russia, the United States, and Japan in the world's titanium industry, and it has become one of the world's major titanium industry powers
.
Especially in 2010, the production capacity and output of sponge titanium and titanium processing materials both ranked first in the world, and the equipment level has reached the world's first-class level.
It has become a veritable titanium industry power, but it is not yet a strong titanium industry.
The production technology and production technology of some products The quality can't meet the high-end demand
.
In 2019, the global production of titanium sponge reached 2.
1 million tons, an increase of 300,000 tons compared with 2018; China's titanium sponge production capacity increased by 47.
7%, and the output reached 840,000 tons
.
In terms of market demand, in 2019, the domestic demand for high-end sponge titanium exploded, and the import volume increased by 45.
2%.

.
In terms of corporate competition, Pangang Titanium, Luoyang Shuangrui, Guizhou Zuntai and Chaoyang Parkson have an annual output of more than 100,000 tons; in terms of regional competition, Liaoning and Sichuan are the main production areas of sponge titanium in China
.
From the perspective of macro-control, the current industry situation does not require the increase of sponge titanium production capacity, and should focus on the research and development of new technologies and new production equipment to push the application of the sponge titanium industry to deeper and broader areas
.
Enterprises strive to master and absorb the technology of leading companies in the industry, open up their own market and new areas of application of titanium sponge, and implement the national call for energy conservation and emission reduction, so as to promote the steady development of China's sponge titanium industry
.
Sponge titanium production process The current method of producing sponge titanium is mainly the magnesium thermal reduction method
.
The magnesium thermal reduction method, also known as the Kroll method, was proposed by William Kroll in 1937 and realized the industrial-scale production of sponge titanium in 1948
.
This method is currently the most widely used titanium sponge production process in the world
.
Kroll process flow chart The Kroll process is carried out in a closed steel reactor
.
Put pure metallic magnesium into the reactor and fill it with inert gas, heat it to melt the magnesium, and pass TiCl4 into it at a certain flow rate at 800-900°C to make it react with the molten magnesium
.
The reaction formula is: at the reaction temperature, the generated MgCl (melting point is 2 714°C) is in a liquid state and can be discharged in time .
Under the conditions of 900-1000°C and a certain degree of vacuum, the residual MgCl2 and Mg are vacuum distilled out to obtain sponge-like titanium metal .
The reaction product MgCl2 is electrolyzed to regenerate Mg and Cl2 and reused .
 


The Kroll method also reveals some problems in actual production: for example, the waste gas and wastewater produced during the production process pollute the environment; the utilization rate of magnesium in the reaction is low (about 70%) and the loss is large; the electrolysis of MgCl2 consumes a lot of energy, about It accounts for 28% to 34% of the total energy consumption
.
So far, the Kroll method is still the most commonly used process for producing titanium sponge in the world
.
Although other production processes have not been used in large-scale industrialization, they have been developed in the direction of low cost, environmental protection and energy saving, which is also the future trend of titanium metal production
.
It is hoped that these production processes can complete the breakthrough in industrial production as soon as possible, so that titanium can be used in more industrial and civilian fields
.
Sponge titanium production equipment At present, most of the domestic large-scale sponge titanium industry and titanium metallurgical enterprises are joint production enterprises of magnesium and titanium, and most manufacturers have been adopting a more common and stable integrated reduction-distillation process
.
This process is also called combined method or semi-combined method, which realizes the closed loop of raw material Mg-Cl2-MgCl2
.
The reduction-distillation integrated equipment is divided into two types: inverted "U" type and "I" type
.
The inverted "U" type equipment is formed by connecting the reduction tank (distillation tank) and the condensing tank with a pipe with a valve, and is equipped with a special heating device.
The entire system equipment is assembled at one time before the reduction
.
If the system equipment of the "I" type integrated process is assembled at one time before the reduction, it is called the combined method equipment; and the reduction equipment is assembled first, and after the reduction is completed, the condensing tank is assembled while the system is hot for the distillation operation.
The equipment is called a series connection equipment, and the middle is connected with a "transition section" with a magnesium plug
.
Compared with the United States and Russia, which dominate the production of military aviation titanium materials, the prospects of China’s titanium industry have obvious advantages in civilian titanium materials.
The manufacturing capacity of high-end titanium materials in China is still relatively small, and most of the titanium materials are primary products, and the application fields are also relatively small.
Low-end
.
The proportion of high-end titanium used in aerospace, shipbuilding and other industries is relatively low compared with the global demand structure for titanium materials, and there is ample room for future increments
.
The period when the output determines the price trend has passed, and the titanium market will be dominated by high-end demand in the future
.
As the "14th Five-Year Plan" and the modernization of the military enter a period of acceleration, the use of titanium in high-end fields such as military equipment will increase significantly
.
The national deep-sea development plan and the localization of large aircraft are steadily advancing.
The growth in demand for downstream high-end titanium materials will force the continuous improvement of upstream titanium sponge supply structure.
In the future, high-end sponge titanium will become the mainstream of the market
.
There are many production processes for sponge titanium at home and abroad, but few of them are truly industrialized
.
China's titanium sponge production enterprises should strengthen the introduction and absorption of key technologies, break through the technical bottlenecks in raw materials, chlorination, refining and electrolysis of titanium sponge production, improve the grade of titanium products and reduce energy consumption
.
For China's titanium sponge production enterprises, it is necessary to actively start with the technological transformation of existing production methods and the research and development of new production methods to realize the leap-forward development of titanium sponge preparation technology
.