Heavy metals speciation study revealing merits of anaerobic co-disposal of municipal solid waste with discrete paper mill sludges: An experimental investigation in simulated landfill bioreactors

Abstract Municipal solid waste (MSW) is slow to stabilize under conventional anaerobic landfill conditions, demanding long-term monitoring and pollution control. Provision of aerobic conditions offers several advantages including accelerated leachate stabilization, increased landfill airspace recovery and a reduction in greenhouse gas emissions. Air injection was applied over 130 days to bench-scale bioreactors containing fresh and aged MSW representative of newly constructed and pre-existing landfill conditions. In the fresh MSW simulation bioreactors, aeration reduced the average time to stabilization of leachate pH by 46 days, TSS by 42 days, TDS by 84 days, BOD5 by 46 days and COD by 32 days. In addition, final leachate concentrations were consistently lower in aerated test cells. There was no indication of a gradual decrease in the concentration of ammonia, and it is likely this high ammonia concentration would continue to be problematic in bioreactor landfill applications. This study focussed only on biodegradability of organics in the solid waste. The concentrations of the nonreactive or conservative substances such as chloride and/or heavy metals remain in the bioreactor landfills due to the continuous recirculation of leachate. The results of this study demonstrate the potential for air injection to accelerate stabilization of municipal solid waste, with greatest influence on fresh waste with a high biodegradable organic fraction.

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The fate of heavy metals and salts during the wet treatment of municipal solid waste incineration bottom ash

Waste Management ◽

10.1016/j.wasman.2020.11.049 ◽

2021 ◽

Vol 121 ◽

pp. 33-41

Author(s):

Yanjun Hu ◽

Lingqin Zhao ◽

Yonghao Zhu ◽

Bennong Zhang ◽

Guixiang Hu ◽

...

Keyword(s):

Heavy Metals ◽

Municipal Solid Waste ◽

Solid Waste ◽

Bottom Ash ◽

Waste Incineration ◽

Municipal Solid Waste Incineration

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Investigating Leachate Decontamination and Biomethane Augmentation through Co-disposal of Paper Mill Sludge with Municipal Solid Waste in Simulated Anaerobic Landfill Bioreactors

Bioresource Technology ◽

10.1016/j.biortech.2021.124889 ◽

2021 ◽

pp. 124889

Author(s):

Abhishek N. Srivastava ◽

Sumedha Chakma

Keyword(s):

Municipal Solid Waste ◽

Solid Waste ◽

Paper Mill ◽

Paper Mill Sludge

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Energy Treatment of Solid Municipal Waste in Combination with Biomass by Decentralized Method with the Respect to the Negative Effects on the Environment

Sustainability ◽

10.3390/su13084405 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4405

Author(s):

Miroslav Rimar ◽

Olha Kulikova ◽

Andrii Kulikov ◽

Marcel Fedak

Keyword(s):

Heavy Metals ◽

Municipal Solid Waste ◽

Solid Waste ◽

Process Analysis ◽

Combustion Process ◽

Municipal Waste ◽

Negative Effects ◽

Combustion Properties ◽

Polycyclic Aromatic ◽

Fuel Mixtures

Waste is a product of society and one of the biggest challenges for future generations is to understand how to sustainably dispose of large amounts of waste. The main objective of this study was to determine the possibility and conditions of the decentralized combustion of non-hazardous municipal waste. The analysis of the combustion properties of a mixture of wood chips and 20–30% of municipal solid waste showed an improvement in the operating parameters of the combustion process. Analysis also confirmed that the co-combustion of dirty fuels and biomass reduced the risk of releasing minerals and heavy metals from fuel into the natural environment. Approximately 55% of the heavy metals passed into the ash. The analysis of municipal solid waste and fuel mixtures containing municipal solid waste for polycyclic aromatic hydrocarbons showed the risk of increasing polycyclic aromatic hydrocarbon concentrations in flue gases.

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An Experimental Study on the Melting Solidification of Municipal Solid Waste Incineration Fly Ash

Sustainability ◽

10.3390/su13020535 ◽

2021 ◽

Vol 13 (2) ◽

pp. 535

Author(s):

Jing Gao ◽

Tao Wang ◽

Jie Zhao ◽

Xiaoying Hu ◽

Changqing Dong

Keyword(s):

Heavy Metals ◽

High Temperature ◽

Fly Ash ◽

Municipal Solid Waste ◽

Solid Waste ◽

Liquid Slag ◽

Melting Process ◽

Waste Incineration ◽

Municipal Solid Waste Incineration ◽

Mswi Fly Ash

Melting solidification experiments of municipal solid waste incineration (MSWI) fly ash were carried out in a high-temperature tube furnace device. An ash fusion temperature (AFT) test, atomic absorption spectroscopy (AAS), scanning electron microscope (SEM), and X-ray diffraction (XRD) were applied in order to gain insight into the ash fusibility, the transformation during the melting process, and the leaching behavior of heavy metals in slag. The results showed that oxide minerals transformed into gehlenite as temperature increased. When the temperature increased to 1300 °C, 89 °C higher than the flow temperature (FT), all of the crystals transformed into molten slag. When the heating temperatures were higher than the FT, the volatilization of the Pb, Cd, Zn, and Cu decreased, which may have been influenced by the formation of liquid slag. In addition, the formation of liquid slag at a high temperature also improved the stability of heavy metals in heated slag.

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Determination of Residual Heavy Metals in an Incinerator Bottom Ash from Municipal Solid Waste Power Plant

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.901.65 ◽

2020 ◽

Vol 901 ◽

pp. 65-71

Author(s):

Woravith Chansuvarn

Keyword(s):

Heavy Metals ◽

Power Plant ◽

Municipal Solid Waste ◽

Solid Waste ◽

Microwave Digestion ◽

Bottom Ash ◽

Flame Atomic Absorption ◽

Digestion Technique ◽

Relative Standard ◽

Copper Zinc

Bottom ash is a part of by-product from the municipal solid waste power plants which is always a wider problem for the urban and rural communities due to its disposal plants may cause serious environmental pollution. This work was focused on the residual heavy metal in an incinerator bottom ash from the municipal waste power plant placed in Nongkham district, Bangkok. Four bottom ash samples were obtained in 2017. After drying and grounding, the bottom ash samples were prepared to clear solution with the microwave digestion technique using nitric, hydrochloric and hydrofluoric acid under the heating program. The total residual heavy metals in the incinerator bottom ashes, such as lead, copper, zinc, and cadmium were determined by using flame atomic absorption spectrophotometer (FAAS) with deuterium background correction. The total concentration of lead, copper, zinc and cadmium were found in the range of 280.40-354.22mg kg-1, 365.35-524.45 mg kg-1, 1,527.25-2,074.34 mg kg-1, and 0.48-1.02 mg kg-1, respectively. The recovery of all metals was found in the range of 89.4-101.2% and the relative standard deviation (RSD) was to be 2.15-3.55 % (n=7). The concentration of zinc, copper, and lead was found high levels, while cadmium was low concentration. Heavy metals in solid waste material occur in different chemical forms and phases. The sample preparation based on the microwave digestion was successfully developed for the waste samples with a good reliability.

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