The device is defective. If the welding seam is not firm, the sealing is not tight, the shell is damaged or corroded, the leakage of equipment gas and liquefied gas will be caused, and a flammable gas mixture will be formed at the leakage, which will cause gas explosion under ignition conditions.
The risk factors of production equipment in air separation unit are as follows
1) The device is defective. If the welding seam is not firm, the sealing is not tight, the shell is damaged or corroded, the leakage of equipment gas and liquefied gas will be caused, and a flammable gas mixture will be formed at the leakage, which will cause gas explosion under ignition conditions.
2) Equipment accessories failure. Due to the imperfection of equipment accessories such as pressure gauge, thermometer, hydraulic gauge, safety valve, flame arrester, pressure relief device, etc., the gas or liquefied gas will leak when the temperature is too high or the pressure is too high in the process, which will cause fire or explosion under the condition of ignition.
3) The safety valve, emergency shut-off valve, vent valve and other pressure relief facilities on the security equipment failure device are blocked or failed, and the vessel may cause explosion due to overpressure.
Molecular sieve is a kind of powdery crystal, with metallic luster, hardness of 3 ~ 5, relative density of 2 ~ 2.8, natural zeolite has color, composition zeolite is white, industrial nitrogen machine is insoluble in water, thermal stability and acid resistance improve with the increase of SiO2 / Al2O3 composition ratio.
Zeolite has a large specific surface area, up to 300 ~ 1000m2 / g, internal crystal plane polarization, is an efficient adsorbent, but also a kind of solid acid substances, industrial nitrogen machine surface acid concentration and acid strength is high, can cause positive carbon ion catalytic reaction.
By adjusting the pore size, the metal ions in the composition can be exchanged with other ions in the solution, so that the adsorption and catalytic properties of the zeolite can be changed, so as to prepare zeolite catalysts with different functions.
The nitrogen production equipment needs to be maintained after a period of operation (3 months is appropriate). In addition to the manufacturer's requirement for timely sampling and testing of purifier particles, all we can do is to empty the equipment and heat the equipment to remove the dry ice, water, hydrocarbons and other dust particles inside.
The method of purging can be divided into two stages, depending on the specific situation. Integral blowing method: literally, it doesn't need to purge section by section. For example, regular maintenance only needs to close the expander and lower the liquid level of the upper and lower towers.
Use compressed air to heat the nitriding chamber (distillation tower). When the temperature reaches above 0 ℃, check whether there are impurities or water coming out of the exhaust gas muffler. If not, start the machine directly. The steps are the same as above.