Does the acetylene system used in calcium carbide PVC contain acid?
Thread Content
Calcium carbide process for PVC, pentastar cleaning with sodium hypochlorite; pre-cleaning for washing is done using waste sodium hypochlorite. Is there any acid present in the system? Is the compressor corroded? Are there any good ways to deal with it? Urgent! Urgent! Urgent! ! ! If we don’t fix the compressor soon, it’s going to stop working and I’ll lose my job :(:(:(
In cases where acidity is present, the most obvious indicator is the pH value of the water in the gas tank; another way to detect it is by using a pH test strip when draining the water used in the compressor’s operation. Corrosion of the compressor impeller is less of a concern; first, check the compressor’s gas-water separator, especially the areas where gaseous acetylene comes into direct contact – it is possible to noticeably observe thinner wall thicknesses in such areas, and there are actual examples of this. Do the wastewater from the alkali scrubber tower and the wastewater from the cleaning tower both return to the scrubber tower? Then there’s that previous set of equipment for recovering acetylene gas from waste sodium hydroxide; it recovers wastewater and acetylene gas while discharging slurry, which is great.
We’ve confirmed that it’s acidic acetylene here; is there any good way to deal with it?
Currently, the pH of the water in the gas holder is checked regularly, and alkali is added at scheduled intervals.
Alkali is regularly added to the gas tank, and its material has been changed to 304 stainless steel; currently, it is mainly the compressor that is severely corroded.
The working water is changed frequently; if necessary, a 32% liquid alkali line is added to the water supply pipeline.
Installing an alkali scrubber in front of the compressor can address the acidity issue in the compressor as well as that in the gas holder
The treatment of waste alkali from the alkali washing tower is also a problem
The compressor impeller is made of 316L, with the casing lined with plastic.
Isn’t there a pure water circulation system at the top of your water washing tower? The gas tank has been replaced with stainless steel; there must be chlorine in the acid – isn’t it afraid of corrosion?