基于分子水平反应动力学模型研究供氢剂对热转化过程产物分布的影响规律

Influence of Hydrogen-Donating Agents on Product Distribution in ThermalConversion Process Based on Molecular-Level Reaction Kinetics Model

为实现延迟焦化工艺优化与重油资源的高效利用,从热转化反应机理出发,利用基于结构导向集总方法建立的分子水平延迟焦化反应动力学模型,计算不同工艺条件下汽油、柴油产物中烃族组成和典型分子含量,并从分子水平揭示工艺条件的影响规律。分子水平的延迟焦化反应动力学模型能够考察不同供氢剂对延迟焦化产物分布的作用机理。模型计算结果表明,四氢萘能够有效地提供氢自由基,提高液体产物收率。当四氢萘添加质量分数为5%时,与未添加四氢萘相比,延迟焦化产物气体和焦炭收率分别下降3.60%和0.80%,液体收率增加4.40%。以增加汽油和柴油收率为目的,催化裂化柴油比焦化柴油更加适合作为供氢剂掺炼。

To realize the optimization of delayed coking process and efficient utilization of heavy oil resources,a molecular-level reaction kinetics model of delayed coking was established based on the structure-oriented lumping method according to the thermal conversion reaction mechanism.Then the model was used to calculate the hydrocarbon group composition and typical molecular content in gasoline and diesel products under different process conditions,reveal the influence law of process conditions from the molecular level,and investigate the effect mechanism of different hydrogen-donating agents on the product distribution of delayed coking.The calculation results of the model show that tetralin can supply hydrogen free radicals effectively and improve the yield of liquid products.When mass fraction of 5%of tetralin is added,the yields of gas and coke of delayed coking products are decreased by 3.60%and 0.80%,respectively,and the liquid yield is increased by 4.40%.With the aim of increasing the yield of gasoline and diesel,catalytic cracking diesel is more suitable for blending and refining as the hydrogen-donating agent than coking diesel.