1) sodium hypochlorite spray purification and neutralization process           
The crude acetylene gas generated in the acetylene generator shall be in contact with the dilute sodium hypochlorite in the first pruging tower, and then in contact with the concentrated sodium hypochlorite in the second purging tower to remove some impurities such as phosphine, hydrogen sulfide etc. in the acetylene gas. Then the acetylene gas shall enter the neutralization tower to remove the acid mist with sodium hydroxide solution. The qualified acetylene gas shall be sent out from the top of the neutralization tower to the gas tank or compression process. Each tower is operated by circulating pump. After the preparation of sodium hypochlorite solution, it is pumped into the second purging tower for use, and the diluted sodium hypochlorite after the concentration is reduced is pumped into the first purging tower as a detergent.

2）Features of sodium hypochlorite spray purification system:
   1. Good corrosion resistance and long service life with the sodium hypochlorite purification method.
   2. Designed and Manufactured stringently as per the national standard for the purification equipment.
   3. 10% silver nitrate test paper doesn’t change the color, meeting the national standard for acetylene purification.
   4. Large processing capacity and continuously operating.
   5. Whole low-pressure flow process, the service life of the compressor can not be affected due to no acid-alkali contents at the outlet of the purification tower.

3) Advantage of sodium hypochlorite spray purification system:
   1. Due to the unique nature of the pharmaceutical intermediate industry, the purification liquid is replenished continuously and automatically, and the residual liquid is drained automatically, which solve the defect of unstable purification quality of the original sodium hypochlorite purification equipment, the equipment can be kept in a most effective operation state by adjusting the supplement amount of the purification liquid as per the amount of acetylene gas processing.
   2. the replenished sodium hypochlorite is fed to the top of the purification tower after being circulated in the pump, and the effective chlorine content can’t exceed the standard, which the safety production can be guaranteed.
   3. Compact structure and small occupation area.
   4. Simple operation and convenient maintenance.
   5. Low equipment investment cost