Department of Environmental Science and Engineering, Centre of Mining Environment, Indian Institute of Technology (Indian School of Mines), Dhanbad, India Jharkhand.
Int J Phytoremediation. 2021;23(6):559-576. doi: 10.1080/15226514.2020.1840510. Epub 2020 Nov 11.
Mining activities causes heavy metal pollution and adversely affect the ecological safety and human well-being. Phytoremediation-biochar synergy can effectively remediate mine spoils contaminated with heavy metals (HM). A review which focuses exclusively on the application of biochar assisted phytoremediation in HM contaminated mine spoil is lacking. Mechanisms of metal immobilization by biochar, potential plants and contaminated biomass disposal methods has also been reviewed. Availability of biochar feedstock and production conditions, optimization of application rate, application techniques, selection of suitable hyperaccumulators and cost optimization of bulk biochar production are the key to a successful biochar-based HM remediation of mine tailings and coalmine spoil. Presently, herbs and shrubs are mostly used as phytoremediators, use of woody trees would encourage a long-term metal sequestration which would reduce the cost of biomass disposal. Also, use of non-edible plants would prevent the plants from entering the food chain. For a holistic biochar-phytoremediation technique, incineration and pyrolysis can effectively dispose contaminated biomass. From the economical viewpoint, the environment cost-benefit analysis should be considered before considering the feasibility of a technology.HighlightsMass scale in-situ biochar production and economics are keys issues.Biochar assisted phytoremediation for HM contaminated mine spoils.Long term studies using woody biomass needs attention.Disposal of contaminated biomass by pyrolysis method.
采矿活动会导致重金属污染，并对生态安全和人类福祉产生不利影响。植物修复-生物炭协同作用可以有效地修复受重金属（HM）污染的矿渣。目前缺乏专门针对生物炭辅助植物修复在 HM 污染矿渣中应用的综述。本文还综述了生物炭固定金属的机制、潜在植物和污染生物量的处理方法。生物炭原料的可用性和生产条件、应用率的优化、应用技术、选择合适的超富集植物以及批量生物炭生产的成本优化是成功进行基于生物炭的矿山尾矿和煤矿矸石山 HM 修复的关键。目前，草本和灌木大多被用作植物修复剂，而使用木本植物将有助于长期固定金属，从而降低生物量处理成本。此外，使用非食用植物可以防止植物进入食物链。对于整体生物炭-植物修复技术，焚烧和热解可以有效地处理污染的生物量。从经济角度来看，在考虑技术可行性之前，应该进行环境成本效益分析。
