水基钻井岩屑烧结砖的制备及性能研究

Preparation and properties of water-based drilling cuttings sintered brick

以水基钻井岩屑(水基钻屑)为原料替代部分页岩制备烧结砖,分析了水基钻屑的化学成分、矿物组成以及热重性能,通过单因素实验确定了水基钻屑掺量、烧结温度、保温时间对烧结砖抗压强度、吸水率、体积密度、线性收缩率等的影响。结果表明,在水基钻屑掺量20%,烧结温度1000℃,保温时间2 h的情况下制得的烧结砖抗压强度为20.34 MPa,吸水率为17.08%,体积密度1.764 g/cm^(3),线性收缩率3.32%。XRD与SEM分析发现,水基钻井岩屑因为石英含量较少,物理性能会随着其掺量增大而显著降低。烧结温度过高和保温时间过长也会导致烧结砖过烧现象的发生,体现在微观上液相大量增加,宏观上则表现为体积密度、抗压强度降低以及吸水率、线性收缩率增大。

The water-based drilling cuttings are used as raw materials to replace part of shale to prepare sintered bricks.The chemical composition,mineral composition and thermogravimetric properties of water-based drilling cuttings are analyzed.The effects of different process conditions(drilling cuttings content,sintering temperature,heat preservation time)on the properties of sintered bricks(compressive strength,water absorption,bulk density,linear shrinkage)are determined through single factor experiments.The results show that when the drilling cuttings content is 20%,the sintering temperature is 1000℃,the compressive strength of the sintered brick prepared under the condition of 2 h insulation time is 20.34 MPa,the water absorption rate is 17.08%,the bulk density is 1.764 g/cm^(3),and the linear shrinkage rate is 3.32%.Through XRD and SEM analysis,it is found that the physical properties of water-based drilling cuttings will decline significantly with the increase of the content of quartz because of the small content.Too high sintering temperature and long holding time will also lead to the occurrence of overburning of sintered bricks,which is reflected in the large increase of liquid phase on the micro level and the decrease of bulk density and compressive strength,as well as the increase of water absorption and linear shrinkage on the macro level.