流化床中造纸黑液催化石油焦气化特性

Gasification Characteristics of Petroleum Coke Catalyzed by Black Liquor in a Fluidized Bed

利用实验室规模流化床气化反应器,考察了造纸黑液对石油焦水蒸气气化反应的催化效果,并分析了其催化反应机理。结果表明,造纸黑液不仅能显著提高石油焦的气化反应活性,还能大幅提高气化气中H2的含量。脱水黑液添加量为黑液与石油焦质量之和的10%时催化效果较好,达到相同气化反应速率时的反应温度比纯石油焦气化低200℃左右;在相同反应温度下提高气化反应速率5倍左右,可提高气化气中H2体积分数约8百分点。黑液中的碱金属活性组分能够破坏石油焦中的C=C芳香结构,同时与石油焦中的碳结合生成活性较高的碳氧复合物C(O),从而提高气化反应速率;碱金属还促进了水煤气变换和CH4水蒸气重整反应,使得H2的生成量增多。因此,造纸黑液是一种有效的石油焦气化生产富氢合成气的催化剂。

The steam gasification characteristics of petroleum coke loaded with black liquor were investigated in a laboratory-scale fluidized bed reactor. The results showed that black liquor could not only effectively improve the gasification reactivity, but also greatly enhance H2 content in the produced syngas. The optimal loading amounts of dewatered black liquor was 10~/00 mass fraction of the sum of black liquor and petroleum coke, which could decrease the gasification temperature by about 200~C for realizing the same gasification activity. Compared with the non-catalytic gasification, the gasification rate of such petroleum coke loaded with black liquor was 5 times higher and the H2 volume fraction in the produced syngas increased by 8 percentage points at the same gasification temperature. The active alkaline metal components in the black liquor could destroy the aromatic C =C bonds in petroleum coke and meanwhile combine with the carbon matrix of the coke to generate a bulk of high-activity C （O） compounds, thus increasing the gasification rate. By facilitating the reactions of water gas shift and steam methane reforming, the gasification of petroleum coke with black liquor produced more H2. All of these showed that black liquor can be an effective catalyst for petroleum coke gasification to produce H2-rich syngas.