China's oxygen industry development status?

I. Introduction to Variable Pressure Adsorption Oxygen Production Variable Pressure Adsorption Oxygen Production has been widely used in non-ferrous metal smelting (copper smelting, zinc smelting, lead smelting, gold smelting, nickel smelting, titanium dioxide, etc.), ferrous metal smelting (blast furnace oxygen-enriched coal spraying iron, electric furnace steelmaking, etc.), oxygen-enriched combustion (industrial boiler, glass furnace kiln, electrolysis of aluminum) with the characteristics of its fast startup-low energy consumption, simple operation, load operation and a wide range of adjustments, and simple maintenance, Chemical gas production (ammonia, methanol, ethylene, ethylene glycol production, etc.), the medical field and sewage treatment (oxygen explosion), pulp bleaching, hydrogen peroxide production, a variety of oxidation in the chemical industry, cement industry, cement, refractory bricks manufacturing, ozone generator, aquaculture, carbon black production, medical health care and so on. Variable pressure adsorption oxygen production has been widely promoted and applied. Especially in today's national industrial economy determined to macro-control of the climate, enterprises to survive and develop, we need to save energy consumption, reduce costs. Oxygen production by pressure change adsorption has its unique advantages in saving overall investment, reducing floor space, saving energy consumption and reducing cost. Since the eighties, with the maturity of the transformer adsorption technology, transformer adsorption has become the main method of obtaining low-cost oxygen in the world where high-purity oxygen is not required. The development of domestic variable pressure adsorption oxygen production, although a late start, but the development speed is very fast, a short period of time has completed the device from miniaturization to large-scale development, and the technology is mature, stable and advanced. With the successful development of new high-efficiency molecular sieve adsorbent for oxygen adsorption and the introduction of new adsorbent from abroad, the energy consumption index of the domestic oxygen adsorption device has reached ≤0.35kwh/m?0?6, which is close to the level of the advanced devices in foreign countries. There have been hundreds of sets of VPSA oxygen generating devices put into operation or under contract manufacturing in China, and the design and manufacturing capacity has reached 35,000m?0?6/h pure oxygen with purity ≥90%. Has successfully run the largest device 12000NM?0?6/hO2, energy consumption is 0.35KWh / M?0?6O2, smooth and reliable operation, and can be adjusted to run variable conditions, such as production (large and medium-sized devices) can be done to adjust the amount of multi-operating conditions to run, purity can be adjusted in the 65% ∽ 93% between, and the output of the adjustment of the amount of operation of the energy consumption basically does not increase. Variable pressure adsorption oxygen production is divided into high-pressure adsorption normal pressure desorption (PSA) and normal pressure adsorption vacuum desorption (VSA) and low-pressure adsorption vacuum desorption (VPSA) three processes. In fact, the three processes are only slightly different operating pressure, the essence is the same. The low-pressure adsorption and vacuum desorption VPSA process is the lowest energy consumption standard, and the device is stable, reliable, economic, advanced technology, representing the trend of PSA development, so now the use of variable pressure adsorption of oxygen generation device is usually said to be VPSA device. Our company recommends and adopts this kind of VPSA device. Relying on the original oxygen generator technology mastered by working for a long time in the leading state-run oxygen generator enterprises and further developed and researched by the technicians, our company has formed its own set of new technology and new process with advanced technology and reliable process by incorporating and absorbing the experience and lessons learned from other oxygen generator enterprises. The research and development of VPSA oxygen generation process has become the main direction and focus of the company's development. The company focuses on the research and development of new high-efficiency radial flow adsorption tower and de-argonization process, in order to seek a higher level of VPSA process, further reduce energy consumption, improve the cost-effectiveness of the device, and enhance market competitiveness. Second, the application of variable pressure adsorption of oxygen 1.Variable pressure adsorption of oxygen in ferrous smelting 1.1 Application of variable pressure adsorption of oxygen in the electric furnace steelmaking Variable pressure adsorption of oxygen in the electric furnace steelmaking has been a lot of successful experience and examples. Taiwan and Japan about 60% ∽ 70% of the electric furnace steelmaking enterprises in the use of pressure adsorption oxygen method of steelmaking. In China with variable pressure adsorption oxygen method of electric furnace steelmaking has been very popular (such as Xilin Iron and Steel Company, A city steel plant, Guiyang special steel plant and Jiangsu Huaiyin Steel Plant, etc.) We analyze the characteristics of electric furnace steelmaking: electric furnace steelmaking itself is in the use of scrap as the main raw material to steelmaking, electric furnace steelmaking is mainly by the arc to melt the steel scrap, oxygen is only in the process of smelting in the electric furnace to help melting and blackout of the process of decarburization of oxygen blowing to produce the chemical heat, to Increase the smelting temperature, because the main rely on electric arc melting, oxygen is only auxiliary, so the oxygen purity requirements are not high (in fact, the electric furnace steelmaking without oxygen can also be steelmaking). Converter steelmaking is different, the main material is blast furnace molten iron, blast furnace molten iron into the converter must be blown into the high purity of oxygen combustion to fully remove the molten iron in the Si, S, P, Mn and other impurities, in order to reduce to steel. It can be seen that the role of oxygen in the converter steelmaking is very large, so the oxygen purity requirements are relatively high. Some information shows that the converter steelmaking to have 99.2% purity (qualified products) of oxygen (general deep-cooling oxygen generator to the purity of oxygen to achieve a high quality grade 99.6%). But there is no information that electric furnace steelmaking must have 99.2% purity of oxygen. Our company is always engaged in manufacturing and supplying oxygen generator and installation and commissioning work, and many iron and steel design institutes have close working contact, for this problem, our company has consulted the relevant experts, the answer is that the pressure change adsorption can be carried out in electric furnace steelmaking, the same as the relevant theoretical information, did not say that 99.2% purity of oxygen must be used to make steel in electric furnaces. In fact, a number of manufacturers in the use of variable pressure adsorption of oxygen for steelmaking, the site of the use of oxygen purity are between 91% and 93%. Some investors ask: "Variable pressure adsorption oxygen purity is lower, can you make special steel?" Electric furnace refining special steel and refining general steel in front of the process is the same, are in the electric furnace by the arc melting scrap, blowing oxygen to help melt and power off oxygen decarburization, blowing oxygen is completed in the electric furnace. Refining this process does not need oxygen blowing. In the electric furnace to add other ingredients to change the composition of the steel, to obtain the required steel. So the electric furnace refining of special steel has essentially the same oxygen requirements as the refining of plain steel. Some investors say that there are ship steel in our steelmaking varieties, and the nitrogen content of smelting with low purity oxygen may have to exceed the standard, causing the steel to be brittle. Variable pressure adsorption can produce more than 93% of the oxygen, 4% of the argon, and 1 to 3% of the nitrogen, argon is not bad for steelmaking, this 1 to 3% of the nitrogen content of certain brands of special steel may cause nitrogen exceeds the standard. The state of low-temperature impact steel, such as ship steel and oil well pipe nitrogen content has a clear regulation, to ≤ 70ppm, the use of alloy steel at room temperature such as spring steel, bearing steel, seamless steel tubes and so on have no clear regulations (more on the general steel has no regulations). And most of our electric furnace steel mills are not refining low-temperature shock-resistant steel, so the scope of transformer adsorption smelting special steel should be very broad. Even if the enterprise according to the market needs to smelt part of the low-temperature impact steel, worried about the nitrogen content exceeds the standard, but also the original preparation for the "fire cut" of the low-temperature oxygen generator or low-temperature liquid tank to switch a part of the oxygen over to complete the temporary smelting task. In fact, the control of nitrogen exceeds the standard to a large extent in the production process control, not in the oxygen purity. For example, the cleanliness of the charge cleaning, pig iron block (or hot load of iron) the size of the addition. I have been to a large-scale electric furnace steelmaking plant in China, the steel plant has been using variable pressure adsorption oxygen equipment as the main unit smelting special steel, the use of oxygen purity ≥ 92%. The plant has been smelting special steel (such as 17Cr2Ni2H, GCr15, 40MMoV, etc.) nitrogen content has been controlled at about 80ppm, which is relatively ideal, and the products have been occupying a considerable market share in the country. The plant's production technology department told us that they mainly do a better job in the production process control, and there is no in order to enhance the purity of oxygen and take any special measures. In fact, most of the electric furnace steelmaking plant smelting more share of special steel, general steel according to less, special steel smelting attention to the number of at the same time pay more attention to the quality of the main focus on the added value of the product, the majority of manufacturers are also according to the single volume production, so it is characterized by the decision of the majority of the intermittent production is mainly used in this situation using pressure adsorption oxygen generation equipment economy is particularly prominent.