College of Resources and Civil Engineering, Northeastern University, Shenyang, China; Science and Technology Innovation Center of Smart Water and Resource Environment, Northeastern University, Shenyang, China.
College of Resources and Civil Engineering, Northeastern University, Shenyang, China; Science and Technology Innovation Center of Smart Water and Resource Environment, Northeastern University, Shenyang, China.
J Environ Manage. 2022 Oct 1;319:115621. doi: 10.1016/j.jenvman.2022.115621. Epub 2022 Jul 15.
The high cost of ordinary Portland cement (OPC) limits the broad usage of cemented paste backfill (CPB). Additionally, improper disposal of arsenic-containing biohydrometallurgy waste (BW) can cause tremendous pollution to the environment. Consequently, BW is used to prepare an alternative cementitious material for CPB in this study. The effect of calcined oil shale residue (COSR) on the binder's characteristics was studied. The reaction kinetics of the binder in the presence of COSR were studied via the isothermal calorimeter test and the Krstulovic-Dabic model; mechanical strength and hydration product modifications due to the addition of COSR were also investigated. The leaching of hazardous elements from the binder was also investigated. The results showed that adding COSR reduced the flowability of fresh slurry and early-age compressive strength; however, adding 20 wt% COSR resulted in the highest later age compressive strength, thereby reaching ∼43.65 MPa after 60 days. The compressive strength of the CPB sample using the COSR20 as a binder may reach ∼87% of the OPC-based CPB sample. Furthermore, the presence of COSR had no significant effect on the phase assembles but changed the amount of ettringite (AFt) and calcium silicate aluminate hydrate (C-A-S-H). The results of this study show that the prepared binder could be used as an alternative to OPC in CPB.
普通波特兰水泥（OPC）的高成本限制了其在水泥胶结充填（CPB）中的广泛应用。此外，含砷生物冶金废物（BW）的不当处理会对环境造成巨大污染。因此，本研究中使用 BW 来制备 CPB 的替代胶凝材料。研究了煅烧油页岩残渣（COSR）对粘结剂特性的影响。通过等温量热试验和 Krstulovic-Dabic 模型研究了 CORE 存在下粘结剂的反应动力学；还研究了添加 COSR 对机械强度和水化产物的改性。还研究了粘结剂中有害元素的浸出情况。结果表明，添加 COSR 降低了新浆的流动性和早期抗压强度；然而，添加 20wt%的 COSR 导致后期抗压强度最高，在 60 天后达到约 43.65MPa。以 COSR20 作为粘结剂的 CPB 样品的抗压强度可能达到基于 OPC 的 CPB 样品的约 87%。此外，COSR 的存在对物相组成没有显著影响，但改变了钙矾石（AFt）和硅酸钙铝水化物（C-A-S-H）的含量。本研究结果表明，所制备的粘结剂可替代 CPB 中的 OPC。
