Look again at the polyoxymethylene industry "Great Leap Forward"

At present, China's POM production capacity has reached 400,000 tons, which greatly exceeds the demand. The picture shows POM Products produced by a domestic company.

On May 12 of this year, the newspaper reported on the situation that the polyoxymethylene project was launched rapidly in China, reminding companies to prevent oversupply. However, in the second half of this year, the situation of large-scale polyoxymethylene projects by companies has already taken shape.

In early June, CNOOC Tianye Chemical Co., Ltd. started production of the 60,000-ton polyoxymethylene unit C line.

On August 3rd, Shandong Zibo Hi-tech Zone and Shandong Baoli Polymer New Material Co., Ltd. signed a contract to build an annual output of 25,000 tons of polyformaldehyde.

On September 15, the project of the annual production of 240,000 tons of polyformaldehyde by the same coal group officially commenced its foundation. According to the group, after the completion of the project, the company will become the largest polyoxymethylene production base in the world.

On September 25th, Shenhua Ningmei Coal Group's 60,000 tons/year polyoxymethylene plant went into operation.

According to industry insiders, the characteristics of polyoxymethylene industry development this year are many construction projects and more production projects. In more than a year, domestic POM production capacity has increased from 100,000 tons last year to the current 400,000 tons, an increase of 3 times. It has been pointed out by industry insiders that 2011 is a period of great development for POM in China. It is understood that during the "Twelfth Five-Year Plan" period, there are still many companies planning to launch this project.

In the face of a boom in POM projects around the world, more people in the industry expressed deep concern.

Although the production capacity of domestic polyformaldehyde is large and the number of projects is large, all the products produced by the company are large road goods. This is one of the recognized crux of the domestic polyoxymethylene industry.

“Some domestic companies can't fully understand POM this product. They only know that this is a new material and they are blindly launched. However, after POM is produced, it is an ordinary brand product that has to be modified, otherwise it will And its production of raw materials like methanol into a surplus." Inner Mongolia CNOOC Amano Chemical Group, deputy general manager Han Qiu told reporters.

According to Han Qiu, although POM is an engineering plastic with better overall performance, it has disadvantages such as low impact toughness, poor heat resistance, and large friction coefficient. This greatly limits the use of polyoxymethylene in various fields. Therefore, it is necessary to improve the heat resistance, rigidity, fatigue resistance, creep resistance, and mechanical properties of polyoxymethylene by modification. If polyoxymethylene is modified, it can reach dozens of series and hundreds of varieties, and the added value of the products is very high. At present, ordinary brand polyoxymethylene products are priced at 10,000 yuan/ton per ton. However, after modification, the value of most products can be increased by 3 to 4 times. Some polyoxymethylene modified used in the field of aerospace, can increase the value of more than 30 times, the price up to 300,000 yuan / ton. In Jiangsu and Zhejiang provinces, some plastics processing companies only added some colors to polyoxymethylene, which made them very profitable. With the success of the domestic polyoxymethylene project, domestic ordinary brand products have experienced overcapacity and low-price competition. Modification has become an effective way to increase the added value of polyoxymethylene. However, it is a pity that domestic polyoxymethylene enterprises mainly produce general-purpose products, and there are not many modified products.

Why is it difficult to open the way of modifying polyoxymethylene products in China?

The application market is not fully open. A senior engineer of Shanghai Bluestar Polyformaldehyde Co., Ltd. told the reporter that the polyoxymethylene products with common brands are currently used in the market, and the proportion of modified products in the total market is not large. The modification is to increase the added value of the market. However, the modification is particularly targeted. For example, although they are all polyoxymethylene products, the steering wheel assembly and the door lock assembly of the automobile have a great difference, which requires companies to go deep into the market. In order to find out more market for POM, the market can gradually expand. He said that neither the manufacturer nor the application manufacturer would dare to use the new modified products if they could not understand the characteristics of polyoxymethylene and its application fields. If there are parts that can use modified materials or other products, the designer will definitely prefer to select the applied materials instead of adopting new products.

Zheng Baoshan, deputy director of the Petrochemical Industry Planning Institute of the Petroleum and Chemical Industry Institute, also believes that the current application of new materials in China is what the other party is used to using. For example, it is applied to automobiles and various automotive manufacturers have already formed application habits. Changes to a material, molds and other facilities must also be changed, if the price gap is not great, manufacturers will not easily change, so the application of polyoxymethylene modified products is more difficult.

Businesses are going their own way. Yan Shengbo, deputy chief engineer of Yannan Mining Group Lunan Fertilizer Plant, told reporters that for polyoxymethylene modification, different research institutes and polyoxymethylene production enterprises are not in the same direction. Everyone invests in adding hardware to carry out modified formulation research. . However, enterprises are kept secret and there are problems of repeated investment, repeated research, and repeated modification. Han Qiu said that this is also a universal problem caused by the revocation of such professional departments as the Ministry of Chemical Industry. Due to the lack of a unified organization of research on products and technologies, which has affected technological progress, the industry has also taken a lot of detours.

In this regard, the industry pointed out that polyoxymethylene production enterprises to engage in modification from the market application a little further, there is still some way to go. Only by working with application customers can the process of modification be accelerated. It is understood that at present, some companies in China have begun to practice. For example, Yuntianhua's POM production project in Chongqing, through cooperation with research institutes and customers, invested 120 million yuan to build a 10,000-ton/year modified engineering plastic project and 15 million square meters/year of high-performance microporous separator. research project. Kaifeng Longyu Chemical Co., Ltd. extends the development of modified polyformaldehyde products as an industrial chain, and has established a combination of production, study and research with 13 famous universities and scientific research institutes in the country, and developed flame retardant, antistatic and Automotive products.

80% of the equipment is imported. At present, most of the technologies used in the polyoxymethylene plants launched in China are imported second-hand technologies. This is another recognized crux of the domestic polyoxymethylene industry.

Han Qiu told reporters that at present the polyoxymethylene project launched by China does not have a set of domestically-made equipment, and the installation is based on the introduction from the front to the back. Yu Shengbo further introduced to reporters that a single polyoxymethylene production line needs more than 400 million yuan in equipment investment, and generally imported equipment accounts for more than 300 million yuan. The main equipment is a trioxane reaction vessel, heat exchanger, granulation screw, reaction screw machine, etc. All rely on imports. In addition, some technology and technology service companies not only have high asking prices for technology transfer fees, but also purchase major equipment from each other, and some have signed exclusive agreements with Japanese screw manufacturers, resulting in very high investment in equipment.

According to Sheng Shengbo, at present, the largest glass-lined reactor that can be manufactured in China is 70 cubic meters, which cannot meet the needs of domestic polyoxymethylene production. Moreover, the larger the reactor volume, the easier it is to deform after spraying, and the support strength will decrease. Therefore, 90 cubic meters of glass-lined reactors used by domestic companies are all imported. At present, China's polyoxymethylene production mainly uses Hong Kong Rich Arts International Engineering Co., Ltd., as well as Polish and South Korean technology. The synthetic reactors used in the Polish process are made of glass-lined materials. The Hong Kong-based Arts Corporation uses zirconia-lined materials. The Korean process-synthesized reactors are made of yttrium- or glass-lined zirconium materials.

Most of the equipment is imported, making the investment in polyformaldehyde in China high and the competitiveness untenable. In this regard, industry sources pointed out that relying on localization of equipment to reduce project investment. Sheng Shengbo pointed out that at present, the capacity of a single polyoxymethylene production line in China is generally 20,000 tons, and the margin left by foreign equipment to increase production capacity is minimal, and it can at most increase the production capacity by 5%. After polyoxymethylene is to be scaled up and cost reduced, it is necessary to increase the capacity of a single set of production lines and expand the volume of the trioxane reaction vessel. This will require accelerating the localization of equipment.

It is understood that only the trioxane reactor and the heat exchanger have a certain localization basis.

A technical director of the original Shanghai Solvent Factory, who had participated in the domestic production of polyformaldehyde, told reporters that the most suitable metal material for the reactor is zirconium. The single polyoxymethylene production line requires two 90-meter-meter glass-lined reaction vessels, with a single price of more than RMB 4 million. Only one reaction vessel, made of zirconium, costs more than RMB 10 million. The person in charge of the technology pointed out that although the price of zirconia is higher than that of eucalyptus glass, it is difficult to handle thorium glass if it is damaged, or it will be scrapped if it is not careful, and zirconium has high strength and advantages.

Zirconium has been localized as early as 3 years ago. Li Xianjun, deputy director of the Ministry of Science and Technology of Baozi Titanium Corporation specializing in the production of zirconium materials, told reporters that, in fact, raw materials zirconium sponge zirconium and zirconium oxychloride produced abroad are imported from China. At present, the price of zirconium in China has begun to decline, reaching more than 400,000 yuan/ton, which is a drop of more than 100,000 yuan/ton from last year. A person in charge of the Western Titanium Industry Co., Ltd. told reporters that he is willing to do some work on the domesticization of POM equipment. The domestic Zirconium product has a short delivery time, only 2 to 3 months. If foreign materials are imported, it will be 8~ 10 months, and domestic zirconium has been successfully applied to the production of acetic acid.

Talking about the domesticization of polyformaldehyde equipment, an industry source stated that the key issue is whether POM manufacturers have the risk-taking decision-making power to give opportunities to domestic equipment manufacturers and whether there are suitable technical personnel. He pointed out that as long as China has made the first one, the level of localization of POM equipment will be greatly improved.

Spontaneous process stagnation At present, there are many imperfections in the domestic polyoxymethylene process, and some are even congenital. This is the third crux of the domestic polyoxymethylene industry.

According to report, the research and development of POM in China began in the late 1950s. However, due to many core technologies, there has been no breakthrough, and the level of process technology and device production capacity have not made substantial progress within several decades. In addition to the twin-screw bulk continuous polymerization process and equipment is the technology developed during the "Eighth Five-Year Plan" period, so far, China's polyoxymethylene production has not made any new progress in the improvement of its own process.

A senior engineer of the former Shanghai Solvent Factory who once participated in the localization of polyformaldehyde believes that the problems are concentrated in the following two aspects.

Dilute formaldehyde recovery and disposal issues. The domestic polyoxymethylene production plant, except for the polyoxymethylene plant in Yunfu of Yunnan Province, is equipped with a downstream product****, the rest of the company's equipment for dilute formaldehyde recovery is a distillation program, there is a large amount of recycling, high energy consumption, Equipment requires high quality and investment. Although different manufacturers have different equipment and operation levels, the company produces 1 ton of polyformaldehyde. When the equipment is in stable operation, it needs to consume 10 to 12 tons of steam to treat diluted formaldehyde. At present, domestic companies control the amount of diluted formaldehyde generated by the solution is not ideal.

Equipment corrosion problem. At present, in the polyoxymethylene process used in the country, the key process of the synthesis of trioxane catalyst is the core technology. At present, domestic companies use the catalyst as a catalyst, but the catalyst for the catalyst is very serious and very difficult to handle. And the catalyst is difficult to recover, and it also needs anti-corrosion special equipment such as glass-lined reactor, zirconium-lined reactor, and graphite heat exchanger. In this regard, only the replacement of ** on the catalyst is the real progress and progress of the process. The advantage of replacing the catalyst is that the material requirements of the reactor and the reaction heat exchanger will decrease, and the investment in equipment will be reduced.

In addition, some domestic devices have encountered technical problems after they have been put into operation. To prevent competitors, owners are reluctant to allow design institutes to participate in improvement. This has resulted in a set of defective technologies being transferred many times in China and it is difficult to improve the technology. Experts suggest that domestic polyoxymethylene production enterprises should strengthen communication and communication and promote the improvement of technology based on the problems existing in the operation of the equipment.