Remediation of Bauxite Residue Through Integrated Approach of Microbes and Plantation

Advances in Environmental Engineering and Green Technologies - Handbook of Research on Microbial Remediation and Microbial Biotechnology for Sustainable Soil ◽

10.4018/978-1-7998-7062-3.ch018 ◽

2021 ◽

pp. 475-489

Author(s):

Kumud Dubey ◽

K. P. Dubey

Keyword(s):

Tree Species ◽

Red Mud ◽

Industrial Waste ◽

Bauxite Residue ◽

Integrated Approach ◽

Prosopis Juliflora ◽

Acacia Auriculiformis ◽

Physico Chemical ◽

Cyanobacterial Species ◽

Alumina Industry

Bauxite residue (red mud) is an industrial waste bye product of Alumina industry. It is toxic and highly alkaline in nature having heavy metals. Its disposal is the paramount environmental issue in Alumina industry. In the present study, bioremediation of red mud was carried out through cyanobacteria amendments and plantation. Two cyanobacterial species (viz. Phormidium and Oscillatoria) were found promising after studying their effect on physico-chemical characteristics of red mud. Seeds of selected tree species (viz. Dalbergia sissoo, Prosopis juliflora, Acacia auriculiformis, Pithecellobium dulce, Cassia siamia) were procured, and a nursery of these tree species was raised. Performances of two cyanobacteria (viz. Phormidium and Oscillatoria sps.) in combinations with PSB and VAM on red mud are very encouraging and hold considerable promise for bioremediation and revegetation of red mud. Inoculated seedlings of P. juliflora, P. dulce, A. auriculiformis, and C. siamia performed well for red mud revegetation.

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Removal of Phosphate Using Red Mud: An Environmentally Hazardous Waste By-Product of Alumina Industry

Advances in Physical Chemistry ◽

10.1155/2016/9075206 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 10

Author(s):

Shivkumar S. Prajapati ◽

P. A. Mohamed Najar ◽

Vijay M. Tangde

Keyword(s):

Aqueous Solutions ◽

Red Mud ◽

Selective Adsorption ◽

Bauxite Residue ◽

Selective Removal ◽

Bet Surface Area ◽

Size Analysis ◽

Alumina Production ◽

Heat Treated ◽

Alumina Industry

The industrial waste, bauxite residue generated in the Bayer chemical process of alumina production, commonly known as red mud (RM) has been used as the adsorbent for selective removal of phosphate in aqueous solutions. RM collected from the storage area of alumina industry was characterized by chemical analysis and physical methods such as BET surface area, Scanning Electron Microscopy (SEM), particle size analysis, and X-ray diffraction (XRD) methods. Among the various red mud samples (0.2–200 μ) studied, the samples treated with 1 M HCl for 2 h were found better for the selective adsorption of phosphate in comparison with untreated and heat treated RM samples. The presence of phosphate in the aqueous samples collected after adsorption studies with red mud was determined by standard spectrophotometric procedure using ammonium molybdate and ascorbic acid in nitrate medium at λmax 880 nm. The studies reported significant adsorption of phosphate on acid treated red mud in comparison with adsorption of phosphate on untreated and heat treated red mud, respectively. The adsorption of phosphate on raw red mud and activated red mud was further investigated with respect to stirring time, pH of the solution, dose of adsorbent, and varying phosphate concentration. Acid treated RM is observed as an efficient and cost-effective adsorbent for selective removal of phosphate in aqueous solutions.

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Bulk utilization of industrial waste (bauxite residue) for production of red mud concrete

IOSR Journal of Mechanical and Civil Engineering ◽

10.9790/1684-11650103 ◽

2014 ◽

Vol 11 (6) ◽

pp. 01-03

Author(s):

Deshmukh M.P ◽

◽

Sarode D.D

Keyword(s):

Red Mud ◽

Industrial Waste ◽

Bauxite Residue

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Selective Scandium (Sc) Extraction from Bauxite Residue (Red Mud) Obtained by Alkali Fusion-Leaching Method

10.20944/preprints202111.0413.v1 ◽

2021 ◽

Author(s):

Andrei Shoppert ◽

Irina Loginova ◽

Julia Napol’skikh ◽

Aleksey Kyrchikov ◽

Leonid Chaikin ◽

...

Keyword(s):

Red Mud ◽

Inductively Coupled Plasma ◽

Bauxite Residue ◽

Product Layer ◽

X Ray ◽

Inductively Coupled ◽

Leaching Process ◽

Alkali Fusion ◽

Shrinking Core ◽

Alumina Industry

One of the potential sources of rare-earth elements (REEs) is the solid waste from alumina industry - bauxite residue, known as “red mud” (RM). The main REEs from the raw bauxite are concentrated in RM after the Bayer leaching process. The earlier worldwide studies were focused on the scandium (Sc) extraction from RM by concentrated acids to enhance the extraction degree. This leads to the dissolution of major oxides (Fe2O3 and Al2O3) from RM. This article studies the possibility of selective Sc extraction from alkali fusion red mud (RMF) by diluted nitric acid (HNO3) leaching at pH ≥ 2 to prevent co-dissolution of Fe2O3. RMF samples have been analyzed by X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), electron probe microanalysis (EPMA), and inductively coupled plasma mass spectrometry (ICP-MS). Sc extraction has been found to be 71.2 % at RMF leaching by HNO3 at pH=2 and at 80 °C during 90 min. The kinetic analysis of experimental data by the shrinking core model has shown that Sc leaching process is limited by the interfacial diffusion and the diffusion through the product layer. The apparent activation energy (Ea) was 19.5 kJ/mol. We have established that according to EPMA of RMF, Sc is associated with iron minerals; it could act as the product layer. The linear dependence of Sc extraction of magnesium (Mg) extraction has been revealed. This fact indicates that Mg can act as a leaching agent of Sc presented in RMF by ion-exchangeable phase.

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Phosphorus retention and leachates from sandy soil amended with bauxite residue (red mud)

Soil Research ◽

10.1071/sr9960555 ◽

1996 ◽

Vol 34 (4) ◽

pp. 555 ◽

Cited By ~ 52

Author(s):

RN Summers ◽

DD Smirk ◽

D Karafilis

Keyword(s):

Drinking Water ◽

Red Mud ◽

Bauxite Residue ◽

Nutrient Retention ◽

Application Rate ◽

Rainfall Simulation ◽

Phosphorus Retention ◽

Drinking Water Standards ◽

Application Rates ◽

Alumina Industry

Bauxite residue (red mud) is a finely crushed, alkaline by-product of the alumina industry. The application of red mud to soil has the potential to reduce eutrophication of rivers and waterways by retaining nutrients on infertile sandy soils. The areas which may benefit from amendment with red mud are often groundwater recharge areas for drinking water and those near environmentally sensitive waterways, because of this, the off-site effects of red mud must be assessed before its widespread use. This research aimed to assess the length of time that phosphorus continued to be taken up by red mud and the best application rate of red mud to retain applied phosphorus. The effect of gypsum-amended red mud on phosphorus retention was examined. The composition of leachates from the red mud was compared with drinking water standards for humans and an untreated control. Monthly rainfall was simulated and leachate was collected from lysimeters filled with bleached grey sand amended with 5–80 t/ha of red mud, with and without gypsum. Leachates from over 12 months of simulated rainfall were tested for potential pollutants (Cd, Al, Fe, As, F, SO24-), electrical conductivity, pH, and P. The rainfall simulation was continued for the equivalent of 5 years and P levels were monitored during this time. The ionic concentrations of the leachates from columns treated with red mud were similar to the concentrations in the controls or fell to similar levels after the equivalent of 3 months of rainfall. The concentrations of these leachates were below the maximum recommended limits for drinking water, except in the case of fluoride which only occurred when gypsum was applied. The concentration of fluoride that leached from the gypsum-amended red mud dropped to drinking water standards within the equivalent of 7 months of rainfall. The best application rates of red mud which will reduce phosphorus leaching are 10–20 t/ha, without gypsum. The improved nutrient retention from red mud continues for the equivalent of at least 5 years of fertiliser application.

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Use of Industrial Waste to Produce Ceramic Coatings on Metal

European Journal of Sustainable Development ◽

10.14207/ejsd.2019.v8n5p9 ◽

2019 ◽

Vol 8 (5) ◽

pp. 9

Author(s):

Maria Lucia Pereira Antunes ◽

C.S. Souza ◽

R.F. Moraes ◽

E.C. Rangel ◽

N.C. Cruz

Keyword(s):

Circular Economy ◽

Red Mud ◽

Industrial Waste ◽

Protective Coatings ◽

Bauxite Residue ◽

Ceramic Coatings ◽

Environmental Damage ◽

Chemical Compositions ◽

Foundry Sand ◽

Waste Foundry Sand

Industrial processes are activities that produce large amounts of wastes. Often these wastes are disposed in dam or landfills, occupying large areas and causing environmental damage such as the contamination of water and soil. According to the Circular Economy concept, waste should be minimized and reused as raw material in a new process. This work describes two residues, namely red mud (bauxite residue) and waste foundry sand (WFS), whose chemical compositions indicate their suitability for use as protective coatings. These residues were used to obtain coatings on aluminum alloy by employing plasma electrolytic oxidation (PEO). The PEO process enables the creation of coatings that are durable, uniform, and strongly adherent on metallic components of different shapes. The mineralogical compositions of the coatings were investigated using X-ray diffraction (XRD). Surface wettability was determined by contact angle measurements and evaluation was made of the average surface roughness. Alumina was the main phase observed by XR, indicating good chemical stability and high thermal resistance. The coatings obtained with the red mud were thicker and less rough, compared to those obtained with the WFS. The results demonstrated the feasibility of using these wastes for coating metals in order to improve their properties and enable new applications. Keywords: Industrial Waste, Red Mud, Waste Foundry Sand, Circular Economy, Ceramic Coating.

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Climate resilience through natural regeneration in degraded natural forests of south-eastern hilly region of Bangladesh

Bangladesh Journal of Botany ◽

10.3329/bjb.v48i3.47720 ◽

2019 ◽

Vol 48 (3) ◽

pp. 417-425

Author(s):

Md Khayrul Alam Bhuiyan ◽

Md Akhter Hossain ◽

Abdul Kadir Ibne Kamal ◽

Mohammed Kamal Hossain ◽

Mohammed Jashimuddin ◽

...

Keyword(s):

Tree Species ◽

Natural Regeneration ◽

Diversity Indices ◽

Acacia Auriculiformis ◽

Quantitative Structure ◽

Natural Forests ◽

Climate Resilience ◽

Hilly Region ◽

Major Cluster ◽

Ecological Dominance

A study was conducted by using 5m × 5m sized 179 quadrates following multistage random sampling method for comparative regenerating tree species, quantitative structure, diversity, similarity and climate resilience in the degraded natural forests and plantations of Cox's Bazar North and South Forest Divisions. A total of 70 regenerating tree species were recorded representing maximum (47 species) from degraded natural forests followed by 43 species from 0.5 year 39 species from 1.5 year and 29 species from 2.5 year old plantations. Quantitative structure relating to ecological dominance indicated dominance of Acacia auriculiformis, Grewia nervosa and Lithocarpus elegans seedlings in the plantations whereas seedlings of Aporosa wallichii, Suregada multiflora and Grewia nervosa in degraded natural forests. The degraded natural forests possess higher natural regeneration potential as showed by different diversity indices. The dominance-based cluster analysis showed 2 major cluster of species under one of which multiple sub-clusters of species exists. Poor plant diversity and presence of regenerating exotic species in the plantations indicated poor climate resilience of forest ecosystem in terms of natural regeneration.

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