Comparison of pta production processes

PTA is the abbreviation of purified terephthalic acid, and it is one of the important bulk organic raw materials. Its main use is to produce polyester fiber (polyester), polyester bottle chips and polyester films, which are widely used in chemical fiber, light industry, electronics, construction and other aspects of the national economy and are closely related to people's living standards.

In 2005, the PTA demand in China was 1 265,438+10,000 tons, accounting for 42% of the total PTA demand of 28.8 million tons in the world. The output is 5.6 million tons, the import is 6.5 million tons, and the dependence on imports is 54%. The demand for PTA will continue to expand in the future. In the next few years, it is still difficult to achieve a complete balance between domestic PTA supply and demand.

The demand for EG (ethylene glycol) reached 5102,000 tons, accounting for 45% of the global total demand for EG133,000 tons, with output1/00,000 tons and import volume of 4 million tons. In 2005, China's polyester production accounted for 38% of the world's polyester production, and it has become the most important raw material for China's textile industry. The trend of China has attracted the attention of other countries and regions in the world, and will have a considerable impact on the world chemical fiber industry.

The application of PTA is relatively concentrated. More than 90% of PTA in the world is used to produce polyethylene terephthalate (PET), and other parts are used as raw materials for polypropylene terephthalate (PTT), polybutylene terephthalate (PBT) and other products.

China ranks first in the world in polyester production and is a veritable polyester country. Although the polyester production capacity is still growing at a double-digit rate, the economic benefits have fallen sharply in the previous two years. The main reason is that the prices of PTA and EG remain high, while the prices of polyester products are low, and the profit margin of enterprises is getting smaller and smaller. The self-sufficiency rate of these two raw materials in China is below 40%.

In the past four years, PTA projects in China have become a hot spot, and several large projects have been put into production one after another, but the situation of short supply has not been alleviated. By 20 10, driven by demand and interests, PTA projects will usher in a period of rapid development.

PTA production technology will also develop in the construction. By comparing and evaluating various PTA production processes imported from China in recent years, especially the low-temperature oxidation EPTA process, we can have a more comprehensive understanding of the technical characteristics of existing PTA processes.

Extended data:

Basic use

PTA is one of the important bulk organic raw materials, which is widely used in chemical fiber, light industry, electronics, construction and other aspects of the national economy. At the same time, the application of PTA is relatively concentrated. More than 90% of PTA in the world is used to produce polyethylene terephthalate (PET).

The production of 1 ton PET requires 0.85-0.86 tons of PTA and 0.33-0.34 tons of MEG. Polyester includes fiber chips, polyester fibers, bottle chips and film chips. In the domestic market, 75% PTA is used to produce polyester fiber; 20% is used to produce bottle-grade polyester, which is mainly used for the packaging of various beverages, especially carbonated beverages.

5% is used in film-grade polyester, mainly used in packaging materials, films and adhesive tapes. It can be seen that the downstream extension products of PTA are mainly polyester fibers.

Polyester fiber, commonly known as polyester. Belonging to synthetic fibers in chemical fibers. Synthetic fiber manufacturing industry is the largest and most branched sub-industry in chemical fiber industry. Besides polyester, its products include acrylic fiber, nylon and spandex. In 2005, China's chemical fiber output was16.29 million tons, accounting for 37% of the world's total output of 44 million tons.

The output of synthetic fiber accounts for 92% of the total chemical fiber, while polyester fiber accounts for 85% of synthetic fiber. Polyester is divided into filaments and staple fibers, with filaments accounting for about 62% and staple fibers accounting for about 38%. There are two methods to produce filaments and staple fibers: one is to produce chips from PTA and MEG and melt spinning; One is that PTA and MEG do not produce chips in the production process and spin directly.

Polyester can be used to make special materials, such as bulletproof vests, safety belts, tire cords, fishing nets, ropes, filter cloth and insulating materials. But its main use is as a textile raw material. In domestic textile raw materials, cotton and chemical fiber account for 90% of the total. China's chemical fiber production ranks first in the world. In 2005, of the 26.9 million tons of fiber processing in China textile industry, the output of chemical fiber accounted for 6 1%.

Polyester accounts for nearly 80% of the total chemical fiber. Therefore, polyester is the main raw material of textile industry. Polyester filaments are used by textile enterprises to produce chemical fiber fabrics, and polyester staple fibers are generally blended with cotton. In general, cotton yarn accounts for 60% and polyester accounts for 30-35%. However, the consumption of both has been replaced by price changes.

Simply put, the raw material of PTA is PX, and the source is petroleum. PTA accounts for 75% of the total polyester, while 78% of chemical fiber is polyester. This is the origin of the term "PTA".

Baidu encyclopedia-purified terephthalic acid