Large air separation FAQ

What are the characteristics of structured packed column and sieve tray column in air separation plant?

Switching time of molecular sieve purification

What is the "three Simultaneities" of safety production

What does "three level safety education" mean

What's the reason for using two-stage distillation column in air separation column?

Sieve tray column

Superheated steam

The air separation cold box is filled with insulation material, generally pearlite, and the pearlite particles are filled with air. After the operation of the air separation unit, the temperature of the insulation material and the air will decrease, and the volume will decrease. At this time, if the cold box is well sealed, negative pressure will be formed in the cold box, and the cold box may be compressed under the effect of internal and external pressure difference. If the cold box is not well sealed, the moisture outside the cold box will enter the cold box, making the insulation material damp, and the cold loss of the unit will be greatly increased. In order to prevent the cold box from being compressed and the thermal insulation material from becoming damp, dry nitrogen or crude nitrogen is usually filled into the cold box after the unit is running to keep the cold box at slightly positive pressure.

Pressure test before valve installation 1. In the warranty period, those with the certification and the sealing surface is intact can no longer conduct the strength test alone, but only the air tightness test can be taken before installation. 2. Within the warranty period, it has the certificate, and its sealing surface has defects such as corrosion and damage. After treatment, it must carry out the air tightness test. 3. Outside the warranty period, those with certification and intact sealing surface shall be subject to air tightness test before installation. 4. For valves that need to be degreased and disassembled on site, air tightness test shall be conducted separately before installation. 5. The safety valve shall be sent to the local quality inspection department of the project for verification before the end of installation and commissioning.

The most important index of radiographic quality is the sensitivity of radiography, which is the size of the smallest defect along the direction of ray penetration that can be found on the negative plate quantitatively. Natural defects’ size are hard to be sure. It is obvious that it is unrealistic to use natural defects to evaluate the sensitivity of radiography. Therefore, in order to facilitate the evaluation of photographic quality, it is often used to monitor the image quali...

Before the air cooling columnand water cooling columnare hoisted in place, the anchor hole shall be cleaned, and there shall be no water and debris in the anchor hole.   After the air cooling columnand water cooling columnare hoisted in place, the perpendicularity of the equipment shall be checked. The perpendicularity shall be ≤ 1/1000 and the total length shall not exceed 10mm.   The bottom of the anchor bolt shall not touch the bottom of the reserved anchor hole. Af...

1. Before filling with pearlite, the water accumulated on the foundation surface of air separation unit must be removed, dried with hot air, and all manholes shall be closed. 2. When filling pearlite, all containers and pipes in the cold box should be inflated and kept at 50kPa pressure, then slightly open the valve of each meter pipeline, and all thermometers should be electrified to check whether the thermometer cable is damaged during the filling process. 3. The filled pearlite shall not be mixed with combustibles. 4. When filling with pearlite, coarse mesh or pearlite pouring device should be set at the manhole on the top of the cold box to prevent whole bag pearlite from entering the cold box. 5. After the pearlite is filled, the manhole shall be sealed.