Review on treatment and utilization of barium slag in China

• Published in: Journal of environmental management Vol. 325; p. 116461
• Main Authors: Gu, Hannian, Yang, Yuxin, Guo, Tengfei, Xiao, Jianhua, Gao, Yushi, Wang, Ning
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2023
• Subjects: Barium slag; Harmless treatment; Hazardous waste; Utilization; Barium slag; Hazardous waste; Utilization; Harmless treatment
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2022.116461

Barium slag (BS) is generated as a by-product waste during the production of barium salts from barite. A large amount of BS is discharged annually threating the ecological environment and restricting the development of the barium salts industry. In China, BS is classified as hazardous waste due to its corrosivity, and more importantly because of its extraction toxicity of barium. Soluble barium is toxic and can result in barium poisoning for environment and human beings. The current review presents a detailed summary on general characteristics, discharge and disposal status, harmless treatment pathways and comprehensive utilization of BS in China. BaO, SiO2, CaO, and SO3 occur as main chemical compositions in BS, especially BaO accounting approximately for 35–40%. The mineral compositions include unreacted barite, quartz, clay minerals, newly-formed phases from the side reactions such as BaCO3, BaSiO3 and BaSO3, and residual carbon. A special attention is given to the assessment of the harmless treatment methods for BS from hazardous waste to general waste, which will decrease its management costs. Precipitation and solidification of soluble barium is the common pathway for harmless treatment of BS, and the using of other industrial waste can realize cost-saving. Methods for comprehensive utilization of BS include recovery of barium and carbon, application in building materials, and using as adsorbents for wastewater treatment. In particular, we analyzed and discussed the advantages and disadvantages of these existing process routes, intending to promote potentials for comprehensive utilization of BS in the future. [Display omitted] •BS discharged in China has restricted the development of the barium salt industry.•Efficient management of BS can decrease environmental potentials caused by barium pollution.•Precipitation of barium in BS using other industrial solid waste has a broad prospect.•Harmless treatment used should be beneficial for the subsequent application in other areas.•Comprehensive consideration of barium and carbon recovery is an efficient route for BS utilization.