利用油基岩屑制备水泥路面基层的力学性能及重金属浸出特性研究

油基岩屑是石油开采时产生的危险废物，随着我国石油勘探开发能力的不断提升，因油基岩屑造成的环境污染和资源浪费问题已不容忽视.资源化利用油基岩屑将对油气行业环境保护和可持续发展起到重要促进作用.为探明利用油基岩屑制备水泥道路结构的可行性，制作11种不同配合比的水泥路面基层试件，通过无侧限抗压、劈裂抗拉以及抗压回弹试验，探寻符合相关力学性能要求且岩屑掺加量最大的试件，随即对其开展浸出试验以研究重金属浸出规律，并通过浸出动力学模型拟合重金属长期浸出量.结果表明：(1)随着油基岩屑掺加量的提升，水泥路面基层试件的无侧限抗压强度、劈裂抗拉强度以及抗压回弹模量同时呈下降趋势.当岩屑掺加量为12%时，试件相关力学指标满足《公路路面基层施工技术细则》(JTG/T F20—2015)和四川省农村公路基层材料设计参数要求，此时岩屑掺加量达到最大.(2)Ba、Mn、Pb、Zn为油基岩屑中的特征污染物. Ba、Mn、Pb累积浸出量的变化趋势较为一致，在第64天时基本达到浸出平衡；而Zn的累积浸出量在第64天时仍持续增长. 4种重金属在全浸出阶段的浸出行为都受到扩散控制影响.(3)Ba和Pb的浸出规律符合Elov...

Mechanical Properties and Heavy Metal Leaching Characteristics of Cement Pavement Base Prepared from Oil-Based Drill Cuttings

Oil-based drill cuttings (OBDC) are hazardous wastes generated during petroleum exploitation. With the continuous improvement of China's petroleum exploitation capacity, environmental pollution and wasting of resources caused by OBDC has become more prominent. The utilization of OBDC will play an important role in promoting environmental protection and sustainable development of the petroleum industry. In order to investigate the feasibility of using OBDC to prepare cement pavement base, 11 kinds of cement pavement base specimens with different mixing proportions were made. Through unconfined compression strength, splitting tensile strength, and compressive modulus of resilience tests, the specimen that could meet the mechanical properties specified in Pavement Base Construction Technical Instructions (JTG/T F20-2015) and parameters of base materials for rural roads in Sichuan province were selected. Then, leaching tests were carried out to study the heavy metal leaching behavior, and the long-term heavy metal cumulative leaching amount was fitted through different leaching models. The results reveal that: (1) With the increase of OBDC mixing proportion, the unconfined compressive strength, splitting tensile strength and compressive modulus of resilience of the cement pavement base showed a downward trend at the same time. When the mixing proportion of OBDC reached to 12%, the mechanical properties of the specimen could meet the requirements. (2) Ba, Mn, Pb, and Zn were characteristic pollutants in OBDC. The cumulative leaching amount of Ba, Mn, and Pb reached to leaching equilibrium at 64 days, whereas the cumulative leaching of Zn continued to increase. Overall, the leaching behavior of these four heavy metals was affected by diffusion control. (3) The leaching behavior of Ba and Pb conformed to the Elovich equation, and the second-order kinetic equation was more suitable for describing the leaching of Mn. The long-term heavy metal cumulative leaching amount prediction indicated that more attention should be paid to Mn. The research shows that OBDC could replace certain amount of mineral materials during the preparation of cement pavement base. It is recommended to further expand the utilization scenarios of OBDC to provide a scientific basis for the development of OBDC utilization technology.