Domestic chlorination of titanium dioxide Why alone one seedling?

Titanium Dioxide is currently the best performing white pigment and is widely used in coatings, rubber, plastics, papermaking, printing inks, and household chemicals. Its production has two processes, the ** process and the chlorination process. The chlorination process titanium dioxide production process is a new generation of advanced technology that is internationally recognized as an alternative to ** because of its environmental protection and high product quality. At present, the global chlorination process titanium dioxide and ** titanium dioxide production ratio is approximately 6:4. In developed countries in Europe and America, the proportion of chlorination is higher. As early as 2006, the United States closed its last domestic methano-titanium dioxide plant. In recent years, China has also vigorously promoted the upgrading of the titanium dioxide industry. The chlorination of titanium dioxide in 2005 was listed as an encouragement project in the "Guidance Catalogue for Industrial Structure Adjustment 2005".

However, six years have passed. To date, only one domestic company has adopted the chlorination method.

Why is the domestic chlorination process titanium dioxide industry not developed?

Advantages and Disadvantages of Process

It is understood that although there are conclusions in the international community, there is always great controversy in the Chinese industry as to whether the ** method is good or the chlorination method is good.

One of the points is to advocate the development of the chlorination method. According to Ge Chazhong, director of the Comprehensive Department of the Environmental Planning Institute of the Ministry of Environmental Protection, China's titanium dioxide industry must take the road to chlorination, so that it can only meet the severe challenges of the international market. The elimination of the ** method and the selection of the chlorination method are the trends for the future development of this industry. The reason is simple. The main raw materials for the ** method are ** and titanium concentrates. The quality of the products produced is low, the variety is single, and the environmental pollution is serious. On the contrary, the main raw materials for the chlorination process are high-titanium slag and slag, which are known as clean processes and have many advantages such as high production automation, high product quality, large scale, and low “three waste” emissions.

According to Ge Chazhong, the titanium dioxide production process of the ** method was invented earlier. By 1923, the process had entered a period of growth on a global scale. All countries in the world began to use ** method to produce anatase titanium dioxide products. However, by 1950, the environmental issue of the production of titanium dioxide by the ** method began to be concerned. With the increasingly stringent environmental protection regulations and ever-increasing user requirements for product quality, the more advanced production process chlorination process began to develop in the 1970s. At the end of the 1990s, it exceeded the ** method and occupied a dominant position. At present, chlorination is the first choice for titanium dioxide plants in developed countries. In China, among the nearly 70 titanium dioxide manufacturers, only Jinzhou Titanium Industry Co., Ltd. is the only company that adopts the chlorination process. Therefore, the titanium dioxide industry in China needs to be upgraded.

Another view is that the chlorination method is not completely replaceable. At present, European and American countries in the paper, chemical fiber, ceramics, cosmetics and other industries on the production of anatase titanium dioxide remains strong demand, the future of ** titanium dioxide still has a wide range of applications and market demand, will Long-term coexistence with chlorination of titanium dioxide. At the same time, the domestic ** law does not lag behind. Because domestic companies have worked hard, they have created an improved method. This technology has been greatly improved than the original method, such as the use of acid-soluble titanium slag instead of titanium concentrate as raw material, to achieve the recycling of waste acid concentration, the use of waste heat yellow acid, etc., the production level has been greatly improved. Some of the industry experts including the former Secretary-General of China National Coatings Industry Association, Yue Wangkun, and others held this view.

An industry source who did not wish to be named said that in terms of environmental protection, simply saying that ** pollution is a serious misunderstanding. The main pollution of ** titanium dioxide lies in waste **, but at present, with the promotion of waste acid recycling and reuse technology, the amount of waste acid can be greatly reduced. For example, Sichuan Longhao Company uses all its waste acid for the production of phosphate. Chlorination slag produced by the chlorination method is difficult to handle. At present, many foreign companies transport chlorinated wastes to the deep sea of ​​the high seas for disposal, or landfilled in abandoned sparsely populated mines, which is more harmful to the environment. In terms of raw materials, the current domestic Although there are many titanium mineral resources, there are few high-quality sand minerals. To adapt to the chlorination process, it is also necessary to refine the titanium concentrate into high titanium slag. As a result, the production process of the chlorination process is not necessarily short, and the cost is not necessarily low. A report from the European Union's Joint Research Center shows that, at least in Europe, the chlorination method and the ** method have hidden dangers in different aspects of the environment, and not who is more environmentally friendly. The chlorination method can save energy and reduce wastewater discharge, but its waste is more toxic than the waste generated by the ** method.

Analyst Yang Xun, an analyst at Chemicals, said that in the type of titanium dioxide products, the improved method also has advantages. The modified ** method can produce both high-end rutile titanium dioxide and mid- to low-end anatase titanium dioxide, while the chlorination method can only produce rutile titanium dioxide. Although it can also be converted to anatase, additional processes are required during the conversion process, adding additional costs.

The key technology is difficult to master

The CCIN reporter learned that in the mid-1980s, the domestic Jinzhou Titanium Corporation adopted the technology consulting from foreign companies and the domestic supply of equipment to introduce the chlorination titanium dioxide production technology from the United States and build China’s first set of 15,000 tons/year. Chlorination titanium dioxide production plant. The main reason why we chose to adopt the technology consulting method instead of adopting a full set of technical equipment was that the most important oxidation technology and equipment were Dupont’s “unique skills” and the other party did not transfer it. In 1994, this chlorination titanium dioxide production facility was completed. Due to the complexity of the technology of the project and the incomplete introduction of core technologies and key equipment, the commissioning process of the device was difficult. After many years of technical exploration and research, the production technology problems were solved one by one. Jinzhou Titanium finally developed its first 10,000-ton chlorination titanium dioxide core device—oxidation reactor—in 2001, which solved key technical problems. After nearly 20 years of hard work, the installation, production, and continuous operation of the device have gradually been realized.

However, due to the low level of mastery of the introduction of technical consulting methods to the introduction of the technology, there are still deficiencies in the current domestic chlorination plant compared with the advanced level in the world. First, the operating cycle of home-made oxidation reactors is only 3 weeks or more, but there is still a certain gap compared to the operating cycle of foreign oxidation reactors up to 67 weeks. Second, there is still a certain gap between product quality and foreign countries, which is mainly reflected in the particle size and crystal shape control of titanium dioxide. There are gaps in the indicators such as whiteness, achromaticity, hiding power, and weatherability. Third, in the manufacture of key equipment, the quality of domestic manufacturing cannot be compared with imported equipment. Fourth, there is still a gap between the capacity of single-unit equipment and that of foreign countries.

Bi Sheng, director of the Titanium Dioxide Center of the National Productivity Promotion Center of the Chemical Industry, believes that the chlorination process is indeed the overall development trend of the titanium dioxide industry in the world. However, this development trend is constrained by all factors in China, especially in terms of technical level. Chlorination process and ** method is very different, the production technology and equipment material requirements are very high, and the vast majority of domestic titanium dioxide enterprises can not reach this level of technology. Moreover, we do not have our own independent core technology and it is difficult to introduce key technologies. This is an important reason why the chlorination process has not been promoted in our country.

International giants to spoil

In 2002, DuPont announced the construction of a 200,000-ton chlorination process titanium dioxide project in Dongying, China, with a total investment of US$1 billion and plans to start production in 2010. This is DuPont's largest investment project outside the United States. This news is undoubtedly heavy. We must know that the current market demand for domestic high-grade titanium dioxide is also more than 200,000 tons per year. This DuPont project means that China will dominate the Chinese market for high-grade titanium dioxide.

However, it was later discovered that although the Dupont Dongying project uses advanced chlorination, it uses ilmenite with a content of about 60% instead of the 80% ilmenite used by DuPont's other plants. Some experts questioned the use of low-grade raw materials, suggesting that there are hidden environmental concerns. Therefore, the former DuPont had also planned to set up a factory near Lugang Town in Changhua County, Taiwan, using the same technology and the same raw materials. However, due to opposition from local residents, it was forced to relocate and replace it. Grade ilmenite as raw material.

Liu Changhe, a senior consultant of Jinzhou Titanium Industry, is an expert in the domestic research of chlorination process. He has participated in the environmental assessment of the Dupont Dongying project twice, and both expressed opposition to this project. He said: "The production of this mine will consume more **, produce more toxic waste such as ferric chloride, etc., and the low content of ilmenite contains more radioactive elements * and helium."

In the face of environmental concerns, DuPont stated that it strictly injects waste into deep wells and is "very safe. The diffusion radius within 10,000 years does not exceed three kilometers, which meets the standards of the US Environmental Protection Agency."

This project was identified by the former State Environmental Protection Administration as a demonstration project of China's chemical industrial waste processing. In November 2007, DuPont Company received the original SEPA report of its environmental impact report on the Dongying Titanium Dioxide project.

However, some experts pointed out that the Dupont Dongying project site is located 13 kilometers away from Dongying city center, close to the Laizhou Bay, 25 kilometers north of this project, is the country's largest estuarine delta nature reserve - the Yellow River Delta wetlands, the Yellow River into the sea. Dongying is also home to the Shengli Oilfield, with oil wells. The radioactive elements are poured into the ground and it is bound to have an impact on the local environment.

At present, although the project has passed the EIA, it has not passed the approval of the National Development and Reform Commission, the Ministry of Land and Resources, and local governments. The National Development and Reform Commission has implemented new regulations for the 2011 edition of the Guidance Catalogue for Industrial Structure Adjustment implemented on June 1 this year. It only encourages titanium-rich materials with a titanium dioxide content of not less than 90% (synthetic rutile, natural rutile, and high-titanium. Slag) is a raw material for the production of chlorinated titanium dioxide."

The DuPont project was stagnated due to domestic opposition. However, other domestic companies that have considered the chlorination method have also been strained because of this project and are worried about colliding head-on with this Big Mac.

The CCIN reporter recently interviewed DuPont and wanted to know if they planned to go ahead with the project or give up, but Dupont remained silent on this issue. Perhaps this situation is the effect that DuPont wants: treat this project as a sword of Damocles and hang it on the head of Chinese titanium dioxide enterprises to prevent China from developing chlorinated titanium dioxide and keep DuPont in the international high-grade titanium. White powder market dominance.