基于原位定向焦化脱氮法,首先考察了有机酸、氧化活性炭及实验室自制的DN-1三种脱氮剂脱除含氮化合物的效果。结果显示,DN-1体系的氮脱除效果最为显著。随后对基于DN-1脱氮剂的原位定向脱氮工艺进行了研究。研究结果表明,工艺采用分步焦化,且DN-1水溶液质量分数为25%时,脱氮效果最佳,焦化产物的碱氮质量分数可降至655μg/g,总氮质量分数降为1 889μg/g,达到催化裂化操作的常规要求。
Organic acid,activated carbon,and DN-1( made in laboratory) are used as the denitrifiers in the in situ directional coking denitrification process. Their performances are investigated. The results reveal that DN-1 exhibits the best denitrification performance. The in situ directional denitrification process based on DN-1 is also studied. Two-steps coking process,including 12 hours of pre-coking at 180℃ and the coking process afterward,is undertaken. The best nitrogen removal effect can be achieved when 25% DN-1 aqueous solution is added. The basic nitrogen content and total nitrogen content in coking gas oil can be reduced to 655 ppm and 1889 ppm,respectively,which satisfies the requirements of catalytic cracking.