对煤加氢液化残渣基本物性进行了考察,针对其加热易软化熔融、强黏结性等特性带来的进料困难、热解黏结以及粉尘与热解油气难以分离等问题,构建了集固体热载体快速热解和移动颗粒层除尘为一体的双循环反应系统,探讨了利用该系统连续热解残渣提油的可行性。结果表明,残渣可萃取物占残渣1/2以上,其含有的高分子量有机物使其具有强黏结性。通过配入一定比例惰性物料,可以有效地降低残渣的黏结性。采用螺旋进料器与文丘里进料器组合进料,并配合双层导管冷却的方式可以实现残渣连续顺畅地进料。固体热载体双循环反应系统残渣热解实验表明,采用石英砂掺混进料、流化床快速热解和移动颗粒层过滤除尘技术,可从残渣中高效提取清洁的热解油。热解温度为500℃,流化操作气速比U0/Umf为2. 8,石英砂-残渣掺混比为4∶1时,热解油产率达23%,是铝甑值的2. 1倍。

To extract oil from coal hydroliquefaction residue ( CHR),the basic properties and pyrolysis of CHR in a dual loop reaction system ( DLRS) were investigated in this study. The DLRS was designed to solve the problems caused by the easily softening characteristics and high caking property of CHR such as feeding,caking and dust sepa- ration. It consists of a fluidized bed pyrolyzer,a radial-flow moving bed filter and a riser combustor followed by a parti- cles grading cyclone. These reactors form a pyrolysis loop between the pyrolyzer and the combustor and a filtration loop between the filter and the combustor with small and big inert particles as circulating bed materials,respectively. CHR mixed with the inert material is injected into the pyrolyzer by a gas driven feeder,which makes it possible to dispose the CHR continuously. The dust entrained in the pyrogas from the pyrolyzer would be captured in the filter to get a dust-free tar. The results show that the CHR contains over 50% extractable matter,which leads to its high caking prop- erty. The caking property tends to be weaken after blending a certain amount of inert additives. With the quartz sands as bed materials and the quartz sands-CHR blends (in a volume ratio of 4 ∶ 1) as feedstocks,at a pyrolysis temperature of 500 ℃ and with the nitrogen gas of a superficial velocity about 2. 8 Umf as fluidizing medium in the pyrolyzer, the pyrolysis of CHR on the DLRS has obtained a tar yield of 23% ,which is about two times of the Fischer Assay val- ue.