Abstract: The source of nitrogen, the mechanism of nitrogen poisoning, the influence of nitrogen on catalyst, equipment and device were analyzed according to nitrogen poisoning of semi-regeneration reforming catalysts in three different refineries, and the measures to solve nitrogen poisoning were put forward, such as raw material control, catalyst selection, and increasing liquid phase dechlorination. When the reforming catalyst was polluted by nitrogen, it was necessary to increase the chlorine injection amount temporarily to compensate for the chlorine loss of the catalyst, but it would aggravate the corrosion of the equipment and device. Nitrogen pollution is temporary, and the activity of the catalyst will be restored once the reforming feed met the index requirements. The reason of the high nitrogen content should be found out as soon as possible after nitrogen pollution, and the nitrogen pollution should be eliminated in time. Otherwise, ammonium chloride will be generated at the low temperature part in the system, which will affect the normal operation of the equipment. The most effective measure to prevent the crystallization of ammonium salt is to strictly control the nitrogen content of reforming oil less than 0.5 ug/g in the pre-hydrogenation system.

Key words: semi-regenerative reforming, catalyst, nitrogen poisoning, ammonium salt, equipment, pressure drop