Material selection for the converter.
Thread Content
The sulfuric acid production process includes a step in which sulfur dioxide is converted into sulfur trioxide. The temperature of the first layer of this converter is the highest; it is generally above 500 degrees, but it can exceed 600 degrees during operation. Since the operating temperature of ordinary carbon steel materials is not 500 degrees, it is necessary to purchase a converter with a diameter of 1500 mm. Could you please advise me on what type of material would be suitable for such process requirements?
It’s pilot-scale equipment, right? Pilot-scale applications emphasize cost savings, so carbon steel plus refractory bricks are sufficient.
There are also areas where fire-resistant bricks do not provide sufficient insulation; it is best to use 16-manganese steel plates, and the cost is not much higher.
We use 304L steel plates, along with an insulation layer! Life expectancy of over 5 years!
It is not a pilot-scale device. This converter uses insulation material as its insulation layer (it is not of brick construction). How long can it generally be used? This is because high temperatures cause changes in the properties of the steel plates, leading to a decline in their performance.
There are generally two types: one is high-quality alloy steel (such as 16MnR, etc.), and the other is heat-resistant steel (note the sulfur resistance; please refer to mechanical design manuals or material catalogs)
This is a converter for converting SO2 to SO3, with a diameter of 1600 mm and a height of 5000 mm. It has three layers. The operating pressure is 120 KPa. The inlet temperature of SO2 is 450°C; the temperature in the first layer is 650°C. For the second layer, the inlet temperature is 450°C while the outlet temperature is 500°C. The inlet temperature of the third layer is 450°C and the outlet temperature is 460°C. There is an insulating layer around it, about 50 mm thick. What material should be used to manufacture this equipment?
If cost savings are a concern, high-quality alloy steel (such as 16MnR) can be used; however, care should be taken to maintain heat during welding； If cost is not a concern, use 304L directly; when it comes to insulation, make sure to choose insulation products that meet the required chlorine content standards.
Stainless steel converters eliminate the disadvantages of carbon steel converters, such as poor corrosion resistance, tendency to deform, and leakage. In recent years, they have been widely used in large-scale sulfuric acid production plants in China.
Can it withstand high temperatures of 650 C?
Please see the following link: http://bbs.hcbbs.com/viewthread.php?tid=80406&highlight=304
We use 304L. Aluminum silicate for insulation, thickness 200 MM
If the temperature is only 550 degrees, carbon steel will suffice, but the inner surface needs to be coated with aluminum for protection. Here, the temperature remains around 630 degrees on a constant basis; we use 304 stainless steel, and it has been in use for over 10 years without any problems
I believe that lining the cylinder with Q235-A refractory bricks will suffice, while RTCr16 should be used for the columns and grating plates.
We use ordinary carbon steel for sulfuric acid production. Aluminum silicate insulation bricks for internal insulation; insulation foam for external insulation
Our factory uses stainless steel, along with insulation.
The high-temperature areas in our facility are made of stainless steel
They are high-pressure conversions; the converter is a pressure vessel and should be designed in accordance with pressure vessel regulations.