喷气燃料冰点试验出现悬浮物的探讨

某公司加氢裂化装置生产的喷气燃料在冰点试验时发现了悬浮物,并且悬浮物在回温过程中消失。虽然通过调整原料中催化裂化柴油(简称催化柴油)、外购原料、常三线柴油的掺炼情况,减少原料中芳烃及正构烷烃的含量,但是在冰点试验时依然发现了悬浮物;其次,通过调整反应深度和分馏塔分离效果(喷气燃料馏程),以及对影响喷气燃料质量的其他因素进行排查,仍然未找到出现悬浮物的原因;最后通过化验分析方法排查发现,在干燥环境下(没有湿空气的影响)进行喷气燃料冰点试验时可以避免产生絮状物,说明空气中的水是喷气燃料冰点试验中产生絮状物的直接原因。因此,在进行喷气燃料冰点试验时要采取措施隔绝水分。

DISCUSSION OF FLOCCULE APPEARENCE IN JET FUEL FREEZING POINT TEST

The floccule appeared in the jet fuel of hydrocracking in freeze point test and disappeared when the oil temperature rose. By adjusting the blending ratios of FCC diesel, purchased wax oil and CDU diesel in the raw materials, the aromatic hydrocarbons and n-alkanes components in the raw materials were reduced, the suspended substances were still found in the freezing test, while measures by adjusting the operating conditions, the fractionator effect, the jet fuel distillation range and the other factors affecting the quality of the jet fuel could not eliminate the presence of suspended matter. The laboratory analysis found that no suspension appeared for dried jet fuel. It is the water from air dissolved in the oil that causes the appearance of floc. Therefore, measures must be taken to isolate water when jet fuel is tested at freezing point.