Abstract:Based on the experimental study on fragmentation and pulverization characteristics of polymetallic nodules in the process of ore lifting, it is found that there is obvious fragmentation of nodules during lifting process. With the volume concentration of 6.5%, the mass percent of polymetallic nodules with particle size larger than 50 mm decreases from 75.58% to 23.78%; with the volume concentration of 15%, the mass percent decreases from 51.51% to 10.08%.Pulverization of nodules was observed in the experiment. With the volume concentration of 6.5%, the mass percent of the polymetallic nodules powder with particle size less than 0.1 mm is 1.79%, and the median particle size is 10.07 μm; with the volume concentration of 15%, the mass percent of polymetallic nodule powder with particle size less than 0.1 mm is 1.99%, and the median particle size of the powder is 9.47 μm. Based on the experimental data, it is estimated that as per mining of 10 million tons of polymetallic nodules, the powder discharge will cause tens of thousands of tons of Fe and Mn losses, as well as hundreds of tons of Co, Ni and Cu losses. Besides, the maximum redeposition thickness of the sediment plume induced by mining is more than 3 mm after diffusion and settlement, which will bring a significant impact to environment.
刘美麟, 夏建新, 任华堂. 扬矿过程中多金属结核破碎粉化特性试验研究[J]. 矿冶工程, 2024, 44(1): 1-5.
LIU Meilin, XIA Jianxin, REN Huatang. Experimental Study on Fragmentation and Pulverization Characteristics of Polymetallic Nodules During Lifting. Mining and Metallurgical Engineering, 2024, 44(1): 1-5.
[1] Yesson C, Clark M R,Taylor M L, et al. The global distribution of seamounts based on 30 arc seconds bathymetry data[J]. Deep Sea Research Part I: Oceanographic Research Papers, 2011,58(4):442-453.
[2] Thiel H, Schriever G, Bussau C, et al. Manganese nodule crevice fauna[J]. Deep Sea Research Part I: Oceanographic Research Papers, 1993,40(2):419-423.
[3] Araya J F. New records of deep-sea sea spiders (Chelicerata: Pycnogonida) in the southeastern Pacific[J]. Marine Biodiversity, 2016,46(3):725-729.
[4] Vanreusel A, Hilario A, Ribeiro P A, et al. Threatened by mining, polymetallic nodules are required to preserve abyssal epifauna[J].Scientific Reports, 2016(6):26808.
[5] Miller K A, Thompson K F, Johnston, et al. An overview of seabed mining including the current state of development, environmental impacts, and knowledge gaps[J]. Frontiers in Marine Science, 2018,418(4):1-24.
[6] Wenbin M, Dingena S, Cees V R, Numerical calculations of environmental impacts for deep sea mining activities[J]. Science of The Total Environment, 2019,652:996-1012.
[7] Laura K, Inari H, Kirsi K. Causal Approach to Determining the Environmental Risks of Seabed[J]. Mining Environmental Science & Technology, 2021,55(13):8502-8513.
[8] 国际海底管理局理事会. “区域”内矿物资源开发规章草案——深海海底采矿规范性环境阈值[R]. 牙买加金斯敦:国际海底管理局, 2022.
[9] Hitchin B, Smith S, Kroger K, et al. Thresholds in Deep-Seabed Mining: A Primer for Their Development[J]. Marine Policy, 2023,149:105505.
[10] 唐达生,肖 红,宋跃文,等. 深海粗颗粒矿石浮游速度的试验研究[J]. 矿冶工程, 2016,36(3):1-5.
[11] 饶顺华. 深海采矿船脱水装置设计[J]. 造船技术, 2018(6):10-13.
[12] Nauru Ocean Resources Inc. Collector Test Study Environmental Impact Statement, Testing of polymetallic nodule collector system components in the NORI-D contract area, Clarion-Clipperton Zone, Pacific Ocean[R]. Jamaica: The International Seabed Authority, 2022.
[13] NOROG. Species and Habitats of Environmental Concern, Mapping, Risk Assessment, Mitigation and Monitoring[M/OL]. 2019.
[14] 詹 琳. 深海采矿羽流模拟及其环境影响分析[D]. 北京:中央民族大学, 2023.