Abstract: During processing of coker gatch in the furfural refining unit, coker gas oil contains more light components, which leads to the increase of carrying oil in various parts of the unit and the greater loss of materials and solvents. The distribution and properties of carrying oil and solvent loss were obtained by simulation calculation. Combined with actual operation, it was found that carrying oil was the key of solvent loss, and it was not suitable for refining. By calculating the influence of different reflux media and top temperature on solvent and material loss in the stripping column, it was suggested that the refined oil should be used as reflux to control the top temperature from 100 ℃ to 115 ℃, and the top of stripping column should not be refluxed. When the processing capacity was 44.2 t/h, the refined oil loss was less than or equal to 164.1 kg/h, the extracted oil loss was less than or equal to 185.1kg/h, and the loss of solvent carried away by the material could be reduced to 37.48 kg/h. The problem of hydrogen sulfide in dry distillation coker gas oil could be solved by upgrading the material of pipelines, adjusting the processes and operations. The load of refining oil heating furnace could be reduced by adjusting the heat exchange process, and the fuel gas and circulating water could be saved by 41 m³/h and 19 t/h,respectively. The coke powder in coker gas oil could be removed by adding backwash filter. Through appropriate modification and operational adjustment to deal with the problems of processing coker gas oil in the furfural refining unit, it could provide reference for the optimization of existing industrial units and the design of new units.

Key words: furfural refining, coker gas oil, carrying oil, solvent consumption