Related Experiment Video
Updated: Jul 12, 2026
10:20
Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae
Published on: July 10, 2015
Heavy metals mobility in full-scale bioreactor landfill: initial stage.
Xian Qu1, Pin-Jing He, Li-Ming Shao
1State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, People's Republic of China.
Chemosphere
|August 29, 2007
Summary
Heavy metals (HMs) release from bioreactor landfills decreased significantly after the methanogenic stage was established. Early methanogenesis reduced overall HM pollution, despite initial high releases.
Area of Science:
- Environmental Science
- Geochemistry
- Waste Management
Background:
- Landfills are significant sources of heavy metal (HM) pollution.
- Bioreactor landfills offer potential for enhanced waste decomposition and contaminant control.
- Understanding HM behavior during early landfill operation is crucial for environmental protection.
Purpose of the Study:
- To monitor the release of selected heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) during the initial 20 months of a full-scale bioreactor landfill.
- To investigate the factors influencing heavy metal mobility, particularly the role of humic substances.
- To evaluate the impact of leachate recirculation on heavy metal release dynamics.
Main Methods:
- Monitoring of heavy metal concentrations in landfill leachate.
- Analysis of leachate parameters including TOC and pH.
- Fourier-transform infrared (FT-IR) spectroscopy.
- Chemical speciation modeling using Visual MINTEQ.
Main Results:
- High initial heavy metal release was observed, correlating with high organic matter and low pH.
- Establishment of the methanogenic stage by month five led to heavy metal release below Chinese National Standards.
- Total heavy metal release was less than 1% of deposited material, with most being inorganic.
- Humic substances significantly influenced the mobility of organic heavy metal fractions.
Conclusions:
- The early establishment of the methanogenic stage is key to controlling heavy metal pollution in bioreactor landfills.
- Leachate recirculation can initially increase heavy metal release rates but may reduce total release through accelerated methanogenesis.
- Humic substances play a critical role in the fate and transport of heavy metals within the landfill environment.
Related Concept Videos
01:27Microbial Leaching
Microbial leaching, also known as bioleaching, is an environmentally favorable method for extracting metals from low-grade ores using specific microorganisms. This biotechnological approach is particularly valuable for mining operations targeting copper, gold, and uranium, where traditional extraction methods may be economically or environmentally impractical.Copper Leaching and Microbial CatalysisIn copper bioleaching, crushed ore is arranged into heaps and irrigated with a dilute sulfuric...
01:25Microbial Bioremediation of Uranium
Microorganisms play a critical role in the transformation and immobilization of uranium in contaminated environments through four main pathways: bioreduction, biosorption, bioaccumulation, and biomineralization. These mechanisms reduce uranium’s toxicity and prevent its migration through groundwater systems, offering sustainable approaches for in situ bioremediation.Bioreduction of UraniumBioreduction is driven by anaerobic bacteria such as certain strains of Geobacter and Shewanella, which use...
00:46Bioremediation
Bioremediation is the use of prokaryotes, fungi, or plants to remove pollutants from the environment. This process has been used to remove harmful toxins in groundwater as a byproduct of agricultural run-off and also to clean up oil spills.
01:26Microbial Bioremediation of Hydrocarbons
Bioremediation is an environmentally sustainable process that employs living organisms—primarily microorganisms—to degrade or neutralize pollutants from contaminated environments. In oil spills and hydrocarbon pollution, bioremediation involves the use of hydrocarbon-degrading bacteria to transform toxic compounds into less harmful substances. This approach leverages natural microbial metabolic processes and is considered both cost-effective and ecologically favorable compared to physical or...
01:19Acid Mine Drainage
Mining activities that disturb sulfide-rich rocks, particularly those containing pyrite (FeS₂), initiate a cascade of geochemical and microbiological processes with serious environmental implications. When exposed to air and water, pyrite undergoes oxidation, releasing sulfate, ultimately forming sulfuric acid and mobilizing heavy metals into surrounding water systems. This phenomenon, known as acid mine drainage (AMD), results in low pH waters laden with toxic elements that threaten aquatic...
01:30Microbial Wastewater Treatment
Microbial communities in aquatic ecosystems play a key role in the natural breakdown of contaminants introduced through domestic and industrial effluents. Acting as biological catalysts, these microbes change and mineralize a wide range of organic and inorganic pollutants under different redox conditions.In oxygen-rich surface waters, aerobic heterotrophs lead organic matter breakdown, using oxygen as the terminal electron acceptor to efficiently oxidize substrates to carbon dioxide and water.