加拿大油砂沥青减压渣油在CO/H2-H2O作用下的热改质特性研究

Partial upgrading of vacuum residue from Canadian oil sand bitumen under CO/H2-H2O

    摘要
  • 摘要: 以加拿大油砂沥青大于420℃的减压渣油（BVR）为原料，对比研究其在CO/H2-H2O和N2体系中的热改质特性，通过系统分析BVR在H2-H2O、CO-H2O、N2-H2O等不同氢源下的热改质特性以揭示CO/H2-H2O对渣油热改质的作用机制，最后探讨合成气压力、含水量以及温度对BVR临CO/H2-H2O改质生焦倾向的影响。结果表明，与临氮改质相比，相同反应条件下，合成气和水可使BVR热改质的生焦诱导期延长3.5-6.5 min；相同生焦率（约0.1%）时，合成气和水可显著提升BVR热改质降黏率，410℃时相对临氮改质的降黏率为29.1%，而420℃时可达54.6%。比较不同氢源下BVR热改质的生焦诱导期、改质油黏度和安定性、渣油转化率发现，H2-H2O、CO-H2O、N2-H2O等均对BVR热改质表现出与CO/H2-H2O相同的促进效果，各氢源作用活性的大小顺序为H2-H2O > CO/H2-H2O > CO-H2O > N2-H2O。由此可知，CO/H2-H2O对渣油热改质的促进作用可归因于氢气、CO水热变换新生氢和水热裂解的综合效应，且其中氢气的作用仍最显著。合成气压力、含水量和反应温度可通过影响不同氢源的贡献而调控BVR临CO/H2-H2O改质生焦倾向。低成本易获取的合成气可以提供BVR热降黏改质所需氢源，水能够通过CO水热变换反应供出新生活泼氢而协同合成气实现BVR高效改质。

     

    Abstract: The upgrading of the vacuum residue from Canadian oil sand bitumen was performed in a batch reactor with the syngas (CO/H2) and H2O. The effect of CO/H2-H2O for residue upgrading was verified. In the presence of CO/H2-H2O, the coke induction period is postponed by 3.5-6.5 min. When the coke yield is about 0.1%, the viscosity reduction efficiency can be raised by 29.1% at 410℃ and even 54.6% at 420℃. The upgrading experiments were also carried out in the presence of N2-H2O, CO-H2O, and H2-H2O, respectively. The results show that the capability to inhibit the coke formation was in the order of H2-H2O > CO/H2-H2O > CO-H2O > N2-H2O. The impetus of CO/H2-H2O to BVR upgrading could be attributed to the active hydrogen mainly from H2, nascent hydrogen by water-gas shift reaction as well as aqua-thermolysis. The thermal conditions such as the pressure of syngas, water content and reaction temperature could influence the coking propensity of BVR under CO/H2-H2O by affecting the three different attributions. These results indicate that the more accessible and low-cost syngas could provide the necessary hydrogen for BVR upgrading. Water presents a synergism with syngas for further promoting the BVR upgrading process.

     

    • HTML全文
    • 参考文献(32)
    • 相关文章
    • 施引文献
  • 资源附件(0)

/

返回文章
返回