Abstract:

The directional reflection deep cracking technology developed by the Chinese University of Petroleum was adopted for heater revamping of the 1.2 Mt/a coking plant during overhaul in PetroChina Karamay Petrochemical Co. Ltd. under the preconditions of the constant overall structure of the furnace. In this technology, the tube with oil was heated by fire directively reflected from the furnace wall and the oil in the tube was cracked deeply. After the transformation, the average surface temperature of the tube reduces by 30 ℃, the yield of gasoline and diesel increases 2 percentage points, the coke yield decreases by 1.15 percentage points, and the heat efficiency increases 2.23 percentage points. This means that the measures of changing the tube direction arrangement, increasing the tube number, extending the heavy oil residence time, improving the quantity and quality of heat are in favor of reducing coke yield and increasing gasoline and diesel yield.

Key words: furnace, deep cracking, heavy oil coking