Yuan Pengxing, Li Meng, Chen Shiyi, Xiang Wenguo
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 211189, China.
SINOPEC Nanjing Engineering & Construction Incorporation, Nanjing 210049, China.
ACS Omega. 2024 Sep 11;9(38):39307-39325. doi: 10.1021/acsomega.4c05475. eCollection 2024 Sep 24.
Phosphogypsum (PG) is an industrial hazardous waste product discharged during wet-process phosphoric acid production. Once crystallized, the byproduct PG is filtered and separated from the liquid-phase product and sluiced to the disposal area near the production site for storage, seriously threatening the harmonious symbiosis between humans and nature. Therefore, devising effective solid waste management and cleaner production programs to contain and eliminate PG is of interest to researchers. In this study, the utilization status of PG is comprehensively reviewed, and a feasibility pathway for resourceful recovery of PG is proposed. The key challenges and countermeasures for the high-temperature calcination and decomposition of PG are analyzed and discussed. The visualization analysis based on bibliometrics reveals that the maximum recovery of abundant calcium (as CaO) and sulfur (as SO) in PG and their utilization for the copreparation of calcium-based materials and sulfuric acid are the most suitable solutions for the large-scale application of PG. Five challenges that restrict the commercial promotion of PG calcination and decomposition processes are perfecting the calcium-sulfur conversion mechanism, establishing a process strengthening strategy, developing value-added technology routes, mastering unit scale-up regularity, and conducting sustainable performance assessment. Industrial applications are expected within 10-15 years.
磷石膏（PG）是湿法磷酸生产过程中排放的一种工业危险废弃物。副产物PG一旦结晶，就会从液相产物中过滤分离出来，然后被冲到生产场地附近的处置区域进行储存，这严重威胁着人与自然的和谐共生。因此，制定有效的固体废物管理和清洁生产方案来控制和消除PG，引起了研究人员的兴趣。在本研究中，全面综述了PG的利用现状，并提出了PG资源化回收的可行途径。分析和讨论了PG高温煅烧分解的关键挑战及应对措施。基于文献计量学的可视化分析表明，最大限度地回收PG中丰富的钙（以CaO形式）和硫（以SO形式），并将它们用于共制备钙基材料和硫酸，是PG大规模应用的最合适解决方案。限制PG煅烧分解工艺商业推广的五个挑战是完善钙硫转化机制、建立过程强化策略、开发增值技术路线、掌握装置放大规律以及进行可持续性能评估。预计在10 - 15年内实现工业应用。
