Ecotoxicological risk assessment of revegetated bauxite residue
Around 3 billion tonnes of bauxite residue (BR), the by-product of alumina extraction, have been produced and stockpiled worldwide, representing a potential risk for the environment due to the high alkalinity and the presence of relatively high concentrations of trace elements. Phytoremediation (or simply revegetation) is regarded as the most …
اقرأ أكثر
Growth and nutrition of Hocus lanatus in bauxite residue
It is emerging as a promising in situ remediation method for bauxite residue disposal areas (Khaitan et al. 2010;Ren et al. 2017) discovered that the pH of bauxite residue decreased from 10.60 to ...
اقرأ أكثر
Improvements on physical conditions of bauxite residue …
Introduction. Bauxite residue is a highly alkaline waste discharged from the process of alumina production. In recent years, the global industrial inventory is approximately 5 billion tons, with an annual increase of 200 million tons (Wu et al., 2020).Due to its high saline-alkalinity, and potential environmental risk, the …
اقرأ أكثر
Organic amendments enhanced the humification degree in …
Purpose Revegetation of bauxite residue disposal areas is an effective disposal strategy for large-scale in-situ disposal and reduction of environmental risk. The application of organic amendments is an effective method of increasing the organic carbon content of residue. Humification of bauxite residue by different types of organic …
اقرأ أكثر
Bayer Process Towards the Circular Economy—Soil
The Bayer process used in the refining of alumina from bauxite ore generates a solid, highly alkaline saline-sodic by-product, referred as bauxite residue (BR), with a global estimated annual production of 150 million tons (Mt) and a total global inventory estimated at 4.6 billion tons to date [].The BR is currently disposed of in large purpose …
اقرأ أكثر
Microbial decomposition of biomass residues mitigated …
Effective neutralization of strongly alkaline conditions in bauxite residues (BR) is the fundamental step to initiate the process of eco-engineering BR into growth substrate (or soil-like medium) for direct phytostabilization with pioneer plant species.The present study aimed to evaluate the effectiveness of microbial decomposition of organic …
اقرأ أكثر
Coupling microbial and abiotic amendments accelerates in …
Here we investigated the effects of microbial and abiotic amendments (compost plus tillage), both in isolation and combined, on remediation of key bauxite residue properties in field scale trials (10 × 15 m × 2 m deep field plots). Triplicate residue samples were collected to 30 cm depth from each plot in quarterly field sampling …
اقرأ أكثر
A review of the characterization and revegetation of bauxite residues
Bauxite residue (Red mud) is produced in alumina plants by the Bayer process in which Al-containing minerals are dissolved in hot NaOH. The global residue inventory reached an estimated 3.5 billion tons in 2014, increasing by approximately 120 million tons per annum. The appropriate management of bauxite residue is becoming a …
اقرأ أكثر
Soil properties and earthworm populations associated with bauxite …
bauxite residue amended with compost and gypsum (same rates as before) BRR: bauxite residue from the 12-year-old field-restored site. Adult and juvenile specimens of A. chlorotica (endogeic ecological group) and A. longa (anecic) were collected by digging and hand-sorting from woodland areas on the University College Dublin …
اقرأ أكثر
CSIRO PUBLISHING | Soil Research
The generation of bauxite residue, the by-product of alumina manufacture from bauxite ore, has increased to a global stockpile of some 3 billion tonnes. In the absence of significant reuse options, the bulk of this residue is contained within bauxite residue disposal areas (BRDAs), which can occupy a significant footprint and pose …
اقرأ أكثر
Land Degradation & Development
Weak aggregate stability and low organic carbon content in bauxite residue restrict ecological rehabilitation. To eliminate these restrictions, a 1-year column experiment was conducted to investigate the effects of introducing biosolids (BS), biosolids plus microorganisms (BSM) into bauxite residue on the aggregate stability, changes of …
اقرأ أكثر
Bauxite residue valorization — Soil conditioners …
Request PDF | Bauxite residue valorization — Soil conditioners production through composting with palm oil mill residual biomass | Bauxite residue (BR) is a by …
اقرأ أكثر
Sustainable Bauxite Residue Management Guidance
April 2022. This Guidance explores and explains the sustainable management of bauxite residue. Bauxite residue – also known as 'red mud' – is produced when extracting …
اقرأ أكثر
Bauxite Residue Valorization
Bauxite residue (BR) is a by-product of Bayer process, which is applied for alumina production. Due to its inherent alkalinity and sodicity, the use of BR is globally limited to 2‐–3% of the ...
اقرأ أكثر
Changes in distribution and microstructure of bauxite residue
Bauxite residue is a highly alkaline byproduct which is routinely discarded at residue disposal areas. Improving soil formation process to revegetate the special degraded lands is a promising strategy for sustainable management of the refining industry. A laboratory incubation experiment was used to evaluate the effects of gypsum and …
اقرأ أكثر
Tolerant plant growth improves the conversion of bauxite residue …
Exemplarily, seawater, carbon dioxide, and gypsum are frequently used to improve the physical properties of bauxite residue, while organic wastes like compost and sewage sludge are added to the residue as nutrients; the combined use of these organic-inorganic materials can synergistically achieve alkalinity reduction, nutrient enhancement, …
اقرأ أكثر
Effects of binding materials on microaggregate size
bauxite residue and the stability of water-stable aggregates. Knowledge of the impact of these effects on microaggregate stability is therefore important, ensuring improved manage- ... addition of spent mushroom compost and gypsum reduced clay dispersion and improved microaggregate stability of the restored residues. However, there is still ...
اقرأ أكثر
A field assessment of bauxite residue rehabilitation strategies
Site F: Bauxite residue capped with a compost layer (about 10 cm), for >5 years, and naturally colonized by plants. A schematic description of each sampling site is reported in Table 1. Table 1. Sampling sites grouped according to the rehabilitation strategy. In brackets the number of years since the rehabilitation occurred.
اقرأ أكثر
Environmental consequences of the use of sewage sludge compost …
The use of compost from organic residues is a common practice in soil and land rehabilitation, technosol making, and quarry restoration ... Wong JWC, Ho G (1994) Sewage sludge as organic ameliorant for revegetation of fine bauxite refining residue. Res Conserv Recyc 11(1–4):297–309.
اقرأ أكثر
Availability and transfer of non-essential elements in a
Aims This study investigated a 7 yr old rehabilitated grassland established on a bauxite residue storage areas(RSA) in order to assess the availability and ecosystem transfer of both nutrient and trace elements, and to determine if defined rehabilitation criteria were sustained. Methods Rehabilitated residue/soil was sampled over depth (0–10 and …
اقرأ أكثر
Industrial wastes applications for alkalinity regulation in bauxite
Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda. Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfilled, creating environmental risks either from the generation of dust or migration of filtrates. High alkalinity is the critical factor …
اقرأ أكثر
Bauxite residue valorization — Soil conditioners production …
Bauxite residue (BR) is a by-product of Bayer process, which is applied for alumina production. Due to its inherent alkalinity and sodicity, the use of BR is globally limited to 2–3% of the 150 ...
اقرأ أكثر
Vermicompost and Gypsum Amendments Improve Aggregate Formation …
Improving aggregate formation and stability of bauxite residue is essential for the development of a soil on the residue. Effects of gypsum and vermicompost on related chemical and physical conditions of bauxite residue were studied in a laboratory incubation experiment. The addition of gypsum at 2% and 4% w/w reduced pH and …
اقرأ أكثر
Effective Nutrient Sources for Plant Growth on Bauxite Residue…
In an attempt to promote vegetation cover on bauxite residue, a field trial was established to determine the effect of spent mushroom compost (SMC) and gypsum amendment on enhancing the physical ...
اقرأ أكثر
(PDF) Sustained Bauxite Residue Rehabilitation …
untreated bauxite residue was ∼ 900 mg kg − 1 of bauxite residue, and with exception of concentrations at the surface and at 50 cm there was little variation with depth ( Figure 1, SI Table S2 ).
اقرأ أكثر
Physico‐chemical changes in bauxite residue …
Research Article. Physico-chemical changes in bauxite residue following application of spent mushroom compost and gypsum. R. G. Courtney, S. N. Jordan, T. …
اقرأ أكثر
Straw addition increases enzyme activities and microbial …
Bauxite residue is a highly alkaline solid waste generated from alumina refining through the Bayer process (Xue et al., 2022a). ... Actually, the application of compost and green manure significantly increased microbial biomass and enzyme activities in bauxite residue (Jones et al., 2012; Ke et al., 2021). In addition, the functional microbial ...
اقرأ أكثر
Effectiveness of Bauxite Residues in Immobilizing …
The application of neutralized bauxite residue at 2% (40 tones ha −1 ) to compost/ manure-amended soils could significantly immobilize soluble P, OC, Cu, Mn, Ni …
اقرأ أكثر
A field assessment of bauxite residue rehabilitation strategies
Bauxite residue is the by-product generated from the extraction of alumina from bauxite ore through the Bayer process (Jones and Haynes, 2011). ... Here we investigated the effects of microbial and abiotic amendments (compost plus tillage), both in isolation and combined, on remediation of key bauxite residue properties in field scale …
اقرأ أكثر
Coupling microbial and abiotic amendments accelerates
The objectives were to: (a) demonstrate that microbial bioneutralisation is effective for neutralising residue pH at field scale, building on successful laboratory and glasshouse scale trials; and (b) compare the performance of abiotic (tillage to 15 cm, 40 t/ha compost) and microbial amendments (addition of microbially-neutralised bauxite ...
اقرأ أكثر