Air separation plant development status and direction

What is an air separation plant?

Air separation equipment refers to a device that uses air as raw material to separate various gases such as oxygen and nitrogen in the air by cryogenic separation or adsorption separation. The air separation plant is mainly composed of eight systems, namely compression system, purification system, refrigeration system, heat exchange system, rectification system, product conveying system, liquid storage system and control system.

Air products air separation unit system introduction

1. Compression system: The core device is the air compressor, which is used to pressurize the raw air.

2. Purification system: including air pre-cooling system and molecular sieve purification system. The main device of the air pre-cooling system is an air cooling tower. The main function is to reduce the temperature of the compressed raw air through contact heat exchange, and wash the harmful substances such as acidic substances. Impurities; the main device of the molecular sieve purification system is the molecular sieve adsorber, which is used to further remove moisture, carbon dioxide, acetylene and other substances in the raw air that are harmful to the operation of air separation equipment.

3. Refrigeration system: The main device is a turbo-expander. After a part of the purified and pre-cooled compressed raw air is expanded by the expander, the temperature is further reduced.

4. Heat exchange system: The core device is a plate-fin heat exchanger. The raw material air expanded and cooled by the expander exchanges heat with another part of the compressed raw material air in the plate-fin heat exchanger, so that the compressed raw material air is close to or reaches a low temperature saturated state.

5. Rectification system: It is the core of air separation equipment, mainly composed of low pressure column, medium pressure column and condensing evaporator.

6. Product delivery system: The main devices are nitrogen compressors and oxygen compressors. The product gas can only meet the requirements of the user's subsequent system after being compressed to a certain pressure.

7. Liquid storage and transportation system: It is composed of cryogenic liquid storage tank, tank car, tank container, cryogenic liquid pump and vaporizer for storage, transportation and gasification of cryogenic liquid.

8. Control system: It is mainly a computer distributed control system, which automatically controls the whole process of air separation.

Development status of air separation unit

1. Output

From the perspective of the supply side, from 2015 to 2018, the output of my country's gas separation and liquefaction equipment dropped from 60,900 units to 46,000 units, and the output began to grow rapidly in 2019. According to the data of China General Machinery Industry Association, China's gas separation and liquefaction in 2021 Equipment output increased to 148,500 units, a year-on-year increase of 17.67%.

2. Market size

The domestic air separation equipment industry has experienced many years of development and is already in a mature development stage. In recent years, the market size of my country's air separation equipment has grown rapidly. In 2021, the market size of China's air separation equipment will reach 27.248 billion yuan, a year-on-year increase of 24.4%.

3. Sales

Since 2015, the sales of air separation plants in my country have been on the rise as a whole. In 2021, the sales of air separation plants in China (equivalent to the total oxygen production capacity) will reach 4.838 million m3/h; the sales of air separation plants will reach 350 sets.

Gas separation equipment and the gas products produced by it are widely used, including energy, metallurgy, electronics, chemical industry (coal chemical industry, refining and chemical integration), environmental protection, aerospace, scientific research, health care, food and other fields. Data show that in 2021, my country's air separation equipment sales revenue will reach 28.06 billion yuan, a year-on-year increase of 24.5%.

4. Average price

In terms of price, the average price of air separation equipment in my country has gradually increased from 4,400 yuan/(m3/h) in 2015 to 5,800 yuan/(m3/h) in 2021.

5. Import and export

From the perspective of import and export trade, the export value of my country's air separation equipment is greater than the import value. In 2021, the import value of China's air separation equipment is 351 million yuan, a year-on-year increase of 67.14%; the export value is 1.163 billion yuan, a year-on-year increase of 36.2%.

Development direction of air separation plant industry

The large-scale air separation plant has become the development trend of the industry. First, under the background of my country's "carbon neutrality" policy, carbon emissions are gradually becoming stricter, and industrial enterprises are encouraged to replace old equipment with large and extra-large equipment with lower unit energy consumption. According to the calculation of China Industrial Gas Association, the unit production energy consumption of professional large-scale air separation plants (oxygen production > 5000Nm3/h) is only about 1/2-1/3 of that of small devices (oxygen production <1000Nm3/h). 

In the case of the same total oxygen production, compared with purchasing and building multiple sets of small and medium-sized air separation equipment, purchasing and building a large air separation equipment can save equipment investment, reduce floor space, reduce product energy consumption and operating costs. The second is that industrial enterprises "return to the city and enter the park", the circular development of the park has entered the fast lane, and the centralized supply of the park has made the air separation equipment show a rapid and large-scale trend. The third is the gradual upgrading of the manufacturing technology of downstream enterprises, and the demand for oxygen will also increase.

With the development of large-scale and extra-large air separation equipment, domestic and international enterprises compete on the same stage, and high-level competition will put forward higher requirements for the company's core competitiveness. Enterprises need to strengthen technological innovation, continue to improve the technical level of super-large air separation equipment, and achieve simultaneous development with the international advanced level; adhere to the strategy of high-quality products, continuously improve product and service quality, enhance brand influence and customer loyalty; strengthen cost management, and continuously improve The cost performance of products and services improves the overall competitiveness.