SiO2/S涂层抑制结焦性能的中试对比研究

为了抑制乙烯裂解炉管结焦，对SiO2/S涂层的抑制结焦性能进行了中试试验，并与未涂层炉管和加入结焦抑制剂炉管的结焦结果进行了对比。利用SEM和EDS表征了炉管出口部位结焦层的形貌及成分。结果表明，与未涂层炉管相比，SiO2/S涂层的结焦抑制率为39%，而结焦抑制剂的结焦抑制率为41%，两种工艺条件的抑制结焦效果相当。未涂层、涂层和加入结焦抑制剂的炉管出口结焦层均发生了片状剥落，剥落焦层主要由碳元素组成，且无丝状催化焦存在。涂层和加入结焦抑制剂的炉管剥落焦层厚度约为30 m，而未涂层炉管剥落焦层厚度约为50 m。焦层剥落后的未涂层炉管和加入结焦抑制剂炉管表面为粒状焦，而涂层炉管表面为松散的粉末状焦。

A COMPARATIVE STUDY ON INHIBITING COKING PROPERTIES OF SiO2/S COATING IN PILOT PLANT SETUP

The anti-coking properties of SiO2/S coating was performed in the pilot plant setup, in order to inhibit coking on the inner surface of cracking tube for ethylene production, which was compared with that obtained in the blank furnace tube with and without adding coking inhibitor. The morphologies and components of the cokes on the outlet of the three furnace tubes were characterized by means of SEM and EDS. The results showed that SiO2/S coating reduced the coke formation by 39% compared with that of the blank furnace tube, however, 41% for the furnace tube with coking inhibitor added. The exfoliated cokes, which were found on the outlets of the blank furnace tube, coated furnace tube and the furnace tube with coke inhibitor added, were mainly composed of carbon element, and no filamentous coke is found in the exfoliated coke. The thicknesses of cokes on the coated furnace tube and the furnace tube with coke inhibitor added were 30 m, however, it was 50 m for the blank furnace tube. On the surfaces of the blank furnace tube and the furnace tube with coke inhibitor added there were coke particles after exfoliating cokes. However, the loose coke was found on the surface of the coated furnace tube.