氧化钙对陶粒支撑剂结构和破碎率的影响

Effect of CaO on Structure and Breakage Ratio of Ceramic Proppant

以铝矾土和煤矸石为主要原料,添加不同含量的碳酸钙,在1350℃制备了低成本的陶粒支撑剂,通过X射线衍射(XRD)和扫描电子显微镜(SEM)对陶粒支撑剂的物相组成和微观形貌进行表征。结果表明,添加了碳酸钙的陶粒支撑剂形成新的物相钙长石,随着氧化钙含量的增加,莫来石的晶粒逐渐细化,细化的晶粒提高了陶粒的强度和抗破碎能力。添加量为5wt%碳酸钙的陶粒支撑剂在35MPa、52MPa闭合压力下的破碎率均最低,符合石油天然气行业标准SY/T5108-2014。

Low-cost ceramic proppant was prepared by bauxite and coal gangue as main materials with different contents of additive of CaCO 3 at 1350 ℃. The phase composition and microstructure of ceramic proppant were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results show that the new phase of anorthite was generated by adding CaCO 3. Along with increase of CaCO 3, mullite grains gradually became finer and the refining grains promoted strength and crush resistance. When the content of CaCO 3 is 5wt%, the ceramic proppant displays the lowest breakage ratio under 35 MPa and 52 MPa closed pressure, which meet the requirement of Chinese Petroleum and Gas Industry Standard (SY/T5108-2014).