Centre for Fire, Explosive and Environment Safety, Defence Research & Development Organization, New Delhi, India; Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India.
Centre for Fire, Explosive and Environment Safety, Defence Research & Development Organization, New Delhi, India.
Environ Pollut. 2021 Sep 15;285:117394. doi: 10.1016/j.envpol.2021.117394. Epub 2021 May 19.
Current study was carried out with an objective to remediate highly contaminated sludge with HMX and RDX obtained from an explosive manufacturing facility in North India employing indigenous microbes, Arthrobacter subterraneus (isolate no. S2-TSB-17) and Bacillus sonorensis (isolate no. S8-TSB-4) which were isolated from the same contaminated site. In-vessel composting of the explosive contaminated sludge was performed in 12 different bioreactors using cow manure and garden waste as bulking agents. 78.5% degradation of HMX was observed in reactor no. 2 with Bacillus sonorensis having combination of 10% sludge, 70% cow manure and 20% garden waste on 80th day. Two secondary metabolites Bis(hydroxymethyl)nitramine and methylene dinitramine were identified while studying the degradation pathway. Similarly, degradation of 91.2% was observed for RDX in reactor no. 11 with consortia of Arthrobacter subterraneus and Bacillus sonorensis on 80th day. During the study, release of significant nitrate and nitrite ions were observed. It has already been established that RDX and HMX degradation leads to release of nitrite/nitrate ions. The highest nitrite (reactor no. 11) and nitrate (reactor no. 2) release observed were 24.02 ± 0.05 mg/kg and 30.65 ± 0.99 mg/kg on 50th and 70th day, respectively. Scanning electron microscopic studies confirmed the attachment and presence of microbes with solid surface and no deformation in structure was observed in the microbial cells due to contamination stress. Findings of the study concluded that in-vessel composting assisted with native bacterial species can be a potential technology for the treatment of explosive contaminated sludge at the contaminated sites.
本研究旨在采用从印度北方一家爆炸物制造工厂获得的高污染 HMX 和 RDX 污染污泥，利用从同一污染地点分离的土著微生物——地衣芽孢杆菌（分离株号 S2-TSB-17）和枯草芽孢杆菌（分离株号 S8-TSB-4）进行修复。在 12 个不同的生物反应器中，使用牛粪和园林废物作为膨胀剂，对爆炸物污染的污泥进行容器内堆肥。在第 2 号反应器中，使用枯草芽孢杆菌组合 10%污泥、70%牛粪和 20%园林废物，在第 80 天观察到 HMX 降解率为 78.5%。在研究降解途径时，鉴定出两种次生代谢物双（羟甲基）硝胺和亚甲基二硝胺。同样，在第 11 号反应器中，使用地衣芽孢杆菌和枯草芽孢杆菌组合，在第 80 天观察到 RDX 降解率为 91.2%。在研究过程中，观察到显著的硝酸盐和亚硝酸盐离子释放。已经证实，RDX 和 HMX 的降解会导致亚硝酸盐/硝酸盐离子的释放。在第 50 天和第 70 天，观察到的最高亚硝酸盐（第 11 号反应器）和硝酸盐（第 2 号反应器）释放量分别为 24.02±0.05mg/kg 和 30.65±0.99mg/kg。扫描电子显微镜研究证实了微生物与固体表面的附着和存在，并且由于污染压力，微生物细胞的结构没有观察到变形。研究结果表明，容器内堆肥辅助土著细菌种类可能是处理污染地点爆炸物污染污泥的一种潜在技术。
