Research Status and Environmental Protection Disposal of Recycled Electrolytic Manganese Residue

Abstract Electrolytic manganese residue (EMR) is a common industrial solid waste. The ammonia and manganese components contained in it will pollute the soil environment and have potential risks to human health. Under the premise of investigating the production of electrolytic manganese slag and conventional processes, it is found that the traditional harmless treatment methods of electrolytic manganese slag are still mainly lime solidification, cement solidification, and fly ash solidification, and the resource utilization directions such as cement, concrete, non-sintered bricks, road bases, etc. are mainly used. But, EMR contains ammonia nitrogen, and manganese (prone to leaching) that difficult to meeting environmental protection requirements by using general cement cementitious material solidification. Therefore, this study focused on manufacturing new eco-friendly bricks with EMR using calcination process. Specifically, the physical performance and environmental characterization of the sintered bricks were investigated. Furthermore, the sintering behavior and crystallization of all bricks containing EMR were studied using XRD, FT-IR, and SEM. The results showed the EMR leaching solution contained 1256 mg/L and 8120 mg/L of ammonia nitrogen and manganese, respectively, both of them exceeds Chinese standards (GB 8978-1996). Because of EMR is rich in Fe2O3 and K2O, it greatly promotes particle rearrangement and transfer in the EMR system, reducing the sintering temperature. The compressive strength, leaching performance and radioactivity of sintered bricks with EMR all met the state standard requirement for "sintered common bricks" (GB/T 5101-2017) and (GB 8978). The product can be used as bricks of MU20 grade of Chinese standard. The study provides an effective method for the safe and environmentally friendly disposal of EMR.

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Radioactivity of Five Typical General Industrial Solid Wastes and its Influence in Solid Waste Recycling

Minerals ◽

10.3390/min9030168 ◽

2019 ◽

Vol 9 (3) ◽

pp. 168 ◽

Cited By ~ 2

Author(s):

Zhihui Shen ◽

Qin Zhang ◽

Wei Cheng ◽

Qianlin Chen

Keyword(s):

Solid Waste ◽

Building Materials ◽

Absorbed Dose ◽

Waste Recycling ◽

Solid Wastes ◽

Radium Equivalent Activity ◽

Limit Values ◽

Industrial Solid Waste ◽

Electrolytic Manganese ◽

Electrolytic Manganese Residue

The level of radionuclides is an important index for the preparation of building materials from industrial solid waste. In order to investigate the radiological hazard of five kinds of typical general industrial solid wastes in Guizhou, China, including fly ash (FA), red mud (RM), phosphorus slag (PS), phosphogypsum (PG), and electrolytic manganese residue (EMR), the radiation intensity and associated radiological impact were studied. The results show that concentrations of 238U, 235U, 232Th, 226Ra, 210Pb, and 40K for different samples vary widely. The concentration of 238U was both positively correlated with 235U and 226Ra, and the uranium contents in the measured samples were all of natural origin. The radiation levels of PG, EMR, EMR-Na (EMR activated by NaOH), and EMR-Ca (EMR activated by Ca(OH)2) were all lower than the Chinese and the world’s recommended highest levels for materials allowed to be directly used as building materials. The values of the internal and external illumination index (IRa and Iγ, respectively) for FA and RM were higher (IRa > 1.0 and Iγ > 1.3 for FA, IRa > 2.0 and Iγ > 2.0 for RM). The radium equivalent activity (Raeq), indoor and outdoor absorbed dose (Din and Dout, respectively), and corresponding annual effective dose rate (Ein and Eout) of RM, PS, and FA were higher than the recommended limit values (i.e., 370 Bq/kg, 84 nGy/h, 59 nGy/h, 0.4 mSv/y, and 0.07 mSv/y, respectively), resulting from the higher relative contribution of 226Ra and 232Th. The portion of RM, FA, and PS in building materials should be less than 75.44%, 29.72%, and 66.01%, respectively. This study provides quantitative analysis for the safe utilization of FA, RM, PS, PG, and EMR in Guizhou building materials.

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Simultaneous stripping recovery of ammonia-nitrogen and precipitation of manganese from electrolytic manganese residue by air under calcium oxide assist

Journal of Environmental Science and Health Part A ◽

10.1080/10934529.2015.1055157 ◽

2015 ◽

Vol 50 (12) ◽

pp. 1282-1290 ◽

Cited By ~ 10

Author(s):

Hongliang Chen ◽

Renlong Liu ◽

Jiancheng Shu ◽

Wensheng Li

Keyword(s):

Calcium Oxide ◽

Ammonia Nitrogen ◽

Electrolytic Manganese ◽

Electrolytic Manganese Residue

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Study On Solidification Treatment of Electrolytic Manganese Slag And Numerical Simulation of Slope Stability

10.21203/rs.3.rs-521014/v1 ◽

2021 ◽

Author(s):

Meng Chen ◽

Jianming Wei ◽

Lipei Jia ◽

Qiqi Yao ◽

Yusu Chen

Keyword(s):

Slope Stability ◽

Construction Projects ◽

Negative Impact ◽

Friction Angle ◽

Ammonia Nitrogen ◽

Ecological Environment ◽

Dead Weight ◽

Element Simulation ◽

Electrolytic Manganese ◽

Manganese Slag

Abstract Manganese slag contains a large number of easily migrated heavy metals and ammonia nitrogen and other pollutants, which have a negative impact on the ecological environment. To verify the feasibility of manganese slag as highway subgrade material, manganese slag samples were solidified by mixing fly ash, cement and quicklime, and the solidification effect was compared. The permeability coefficient, cohesion and internal friction angle of manganese slag were measured by permeability test and triaxial test. On this basis, optimization of manganese slag road sections under different slope heights and different slope ratios in a total of 50 schemes was carried out. GeoStudio software is used to perform finite element simulation on the slope stability of manganese slag slopes under dead weight and rainfall. This study provides a reference for highway construction projects using manganese slag.

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