熱作用過程油頁巖顆粒的碎裂/粉化特性

曲洋，初茉，張超，白書霞，暢志兵，郝成亮

（中國礦業大學（北京）化學與環境工程學院，北京 100083）

熱作用過程油頁巖顆粒的碎裂/粉化特性

曲洋，初茉，張超，白書霞，暢志兵，郝成亮

（中國礦業大學（北京）化學與環境工程學院，北京 100083）

在固定床中定量研究了熱作用過程多種工藝因素對油頁巖顆粒的粒度分布及碎裂/粉化程度的影響。結果表明：溫度由120℃升至900℃，固相產物中25～13 mm保持粒級比率由96.54%降至82.69%；13～1 mm碎裂粒群比率由2.01%增至10.63%（13～6 mm粒級增幅最高）；＜1 mm粉化粒群比率由1.45%增至6.68%（＜0.075 mm 粒級變化最顯著）。顆粒尺度的增加及保溫時間的延長亦使得油頁巖的碎裂及粉化程度加劇。多因素灰色關聯分析結果顯示：對油頁巖碎裂程度的影響為：溫度＞粒度＞時間；對粉化程度的影響為：溫度＞時間＞粒度。通過對油頁巖的多種測試表征（TGA、XRF、XRD、SEM-EDS），揭示了上述因素影響油頁巖熱碎的內在誘因（水汽行為、揮發分析出行為、方解石分解行為、時間間接強化、顆粒內部氣阻/材料抗力的影響），并基于此構建了油頁巖熱作用過程碎裂-粉化歷程描述模型。

油頁巖；固定床；熱解；粒度分布；碎裂；粉化；灰色關聯

Abstract:The influence of multiple process factors affecting the oil shale particles size distribution and the degree of fragmentation/pulverization was studied in fixed-bed during thermal effect.The results show that with the temperature increasing from 120℃ to 900℃,the fraction of retention particles (25—13 mm) is decreased from 96.54% to 82.69%.The fragmentation particles group (13—1 mm) are increased from 2.01% to 10.63% (13—6 mm grain size increased the highest rate); The pulverization particles group (less than 1 mm) are increased from 1.45% to 6.68% (the fractions of particles less than 0.075mm are significantly changed).The degree of fragmentation and pulverization are increased with particles size and holding time as well.Impact of multi-factor on fragmentation is revealed using gray relational analysis method as follows: temperature ＞ size ＞ time,and the impact on pulverization is: temperature ＞ time ＞ size.Through the analysis of TGA,XRF,XRD,SEM-EDS,the internal incentives affecting fragmentation/pulverization are revealed: vapor-volatile arising,calcite decomposition behavior,indirect reinforcement with time,and internal air resistance/particle material resistance.The descriptive model of oil shale fragmentation-pulverization in fixed-bed during thermal effect is built based on these factors.

Key words:oil shale; fixed-bed; pyrolysis; particle size distribution; fragmentation; pulverization; gray relational analysis

引 言

油頁巖作為我國非常規油氣資源的主體，是最具潛力的常規能源替代物質[1]。而固定床熱解技術作為其有效煉制的重要載體而被廣泛應用（如撫順爐、茂名爐、Kiviter爐、Petrosix爐等）[2]。但固定床熱解過程油頁巖顆粒所發生的碎裂和粉化現象，使得小粒度顆粒生成量增加，氣體阻力提升，反應器內部布氣方式發生改變，氣相裂解油二次反應增強，收油率有所降低[3-4]。……