煤焦油悬浮床加氢后轻质油生产清洁油品的试验研究

Hydro-upgrading of Light Oil of Coal Tar Suspending-bed Hydrogenation to Clean Fuels

对中低温煤焦油悬浮床加氢后的轻质油(<370℃)进行加氢提质试验研究,以生产硫和氮含量低、安定性好的清洁燃料油组分。加氢提质试验在小型连续固定床加氢装置上进行,重点考察反应温度、反应压力、液时空速和氢油体积比对加氢效果的影响。结果表明,随着反应温度的升高,液时空速的降低,氢耗会增加,最高可达3.66%,液体收率和气产率受反应条件的影响不大,分别稳定在97%～98%和0.10%～0.25%范围内。生成油的氮含量对油品安定性影响较大,当氮含量低于12mg/kg时,生成油的安定性较好。对生成油进一步蒸馏切割得到石脑油馏分(<170℃)和柴油馏分(>170℃)。研究发现,石脑油馏分硫、氮含量较低,芳烃潜含量超过60%,是优质的催化重整原料;柴油馏分受反应条件的影响,其氮含量及十六烷值变化较大。在反应温度为340℃,反应压力为12MPa,液时空速为0.7h^(-1),氢油体积比为800的条件下得到的柴油馏分氮含量为154mg/kg,十六烷值仅为44.3,只能达到0~#普通柴油标准,而在反应温度为360℃,反应压力为16MPa,液时空速为0.5h^(-1),氢油体积比为1 200的条件下得到的柴油馏分氮含量仅为5.7mg/kg,十六烷值高达59.9,可以达到0#车用柴油标准。

In order to product the low content of sulfur, nitrogen and the good stability clean fuel oil component, the hydro-upgrading of light oil (<370 ℃) derived from suspending-bed hydrogenation of mid-low-temperature coal tar was carried out in a fixed reactor. The study focused on the effects of temperature, pressure, liquid hourly space velocity (LHSV) and the hydrogen-oil volume ratio on mass balance and heteroatomic removal. The results show that the consumption of hydrogen increases with temperature rising or LHSV reducing. The maximum consumption of hydrogen is 3.66%. However, the oil yield and gas yield are little affected by reaction conditions. The oil yield and gas yield is about 97%-98% and 0.10%-0.25% respectively. The stability of oil after hydro-upgrading is affected by the content of nitrogen. When the content of nitrogen is lower than 12 mg/kg, the stability of product oil becomes good. The naphtha (<170 ℃) and diesel (>170 ℃) of oil after hydro-upgrading were also investigated. The contents of sulfur and nitrogen of naphtha are low, and the aromatic hydrocarbon potential content is more than 60%. The naphtha can be used as the feedstock of catalytic reforming. The content of nitrogen and cetane number of diesel vary with reaction conditions. The content of nitrogen and cetane number of diesel obtained at reaction temperature of 340 ℃, reaction pressure of 12 MPa, LHSV of 0.7 h^-1 and hydrogen-oil volume ratio of 800 is 154 mg/kg and 44.3 respectively, which can be used as general diesel fuels. However, the content of nitrogen of diesel obtained at reaction temperature of 360 ℃, reaction pressure of 16 MPa, LHSV of 0.5 h^-1 , hydrogen-oil volume ratio of 1 200 reduce to 5.7 mg/kg, and the cetane number is up to 59.9, which can be used as automobile diesel fuels.