Solidification/stabilization of highly toxic arsenic-alkali residue by MSWI fly ash-based cementitious material containing Friedel’s salt: Efficiency and mechanism

Municipal solid waste incineration (MSWI) is a common technique in treatment of domestic waste. This technique annually produces approximately 25 Mt solid residues (i.e., bottom and fly ash) worldwide which is also a major issue in current research. In this research we are concerned with reusing the fly ash (FA) as supplementary cementitious material (SCM) in concrete. Such application solves the problem with heavy metal immobilization as well. To remove the high content of undesired soluble salts, number of washing treatments has been applied. Chemical composition of FA has been examined before and after treatments. The impact of cement substitution by FA in concrete was evaluated by measurement of its compressive strength and durability.

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Residual Strength of Thermally Loaded Mortars with Treated Municipal Solid Waste Incineration Fly Ash Used as Supplementary Cementitious Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.982.114 ◽

2014 ◽

Vol 982 ◽

pp. 114-118 ◽

Cited By ~ 4

Author(s):

Martin Keppert ◽

Kirill Polozhiy

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Municipal Solid Waste ◽

Solid Waste ◽

Building Materials ◽

Cementitious Material ◽

Air Pollution Control ◽

Fly Ashes ◽

Mswi Fly Ash ◽

Supplementary Cementitious Material

Fly ashes collected in Air Pollution Control lines of Municipal Solid Waste Incinerators (MSWI) differ highly from fly ashes generated during coal burning what complicates their utilization in building materials production. Nevertheless after a treatment such ashes can have properties relatively comparable with coal fly ashes and thus can be used as Supplementary Cementitious Material (SCM). The water extracted MSWI fly ash was used as partial Portland cement replacement in mortars. The mortars strength evolution in time was monitored; behavior typical for pozzolans – slower increase of strength – was observed. Influence of thermal load on strength of mortars was studied as well. It can be concluded that water extracted MSWI fly ash can be used as 10 % Portland cement substitute without loss of mechanical properties.

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Investigation on a New Hydraulic Cementitious Binder Made from Phosphogypsum

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.1923 ◽

2013 ◽

Vol 864-867 ◽

pp. 1923-1928

Author(s):

Yue Xu ◽

Jian Xi Li ◽

Li Li Kan

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Active Carbon ◽

High Strength ◽

Tricalcium Silicate ◽

Dicalcium Silicate ◽

Cementitious Material ◽

Saturation Ratio ◽

Tricalcium Aluminate ◽

Cementitious Binder

A new kind of high strength cementitious material is made from phosphogypsum (PG), active carbon and fly-ash. Through the orthogonal research, it was showed that the calcination temperature, retention time, dosage of active carbon and fly ash on the compressive strength of cementitious binder are the most important. The result also showed that, in the conditions of temperature 1200°C, time retention 30 min, dosage of active carbon 10%, dosage of fly ash 5%, the compressive strength of the cementitious material for 3d and 28d could reach to 46.35MPa and 92.70MPa, the content of sulfur trioxide was 11.60% accordingly. A lot of active mineral materials, such as dicalcium silicate, tricalcium silicate, tricalcium aluminate were formed in the calcination. The C-S-H gel, calcium hydroxide and ettringite were found in 3d and 28d hydrates. It is found that the lime saturation ratio and silica modulus need to be control between 0.40~0.65 and 4~8 in order to produce high strength cementitious material.

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A mini-review of heavy metal recycling technologies for municipal solid waste incineration fly ash

Waste Management & Research ◽

10.1177/0734242x211003968 ◽

2021 ◽

pp. 0734242X2110039

Author(s):

Huan Wang ◽

Fenfen Zhu ◽

Xiaoyan Liu ◽

Meiling Han ◽

Rongyan Zhang

Keyword(s):

Fly Ash ◽

Municipal Solid Waste ◽

Solid Waste ◽

Waste Incineration ◽

Electrochemical Process ◽

Chemical Extraction ◽

Air Pollution Control ◽

Municipal Solid Waste Incineration ◽

Mswi Fly Ash ◽

Metal Recycling

This mini-review article summarizes the available technologies for the recycling of heavy metals (HMs) in municipal solid waste incineration (MSWI) fly ash (FA). Recovery technologies included thermal separation (TS), chemical extraction (CE), bioleaching, and electrochemical processes. The reaction conditions of various methods, the efficiency of recovering HMs from MSWI FA and the difficulties and solutions in the process of technical development were studied. Evaluation of each process has also been done to determine the best HM recycling method and future challenges. Results showed that while bioleaching had minimal environmental impact, the process was time-consuming. TS and CE were the most mature technologies, but the former process was not cost-effective. Overall, it has the greatest economic potential to recover metals by CE with scrubber liquid produced by a wet air pollution control system. An electrochemical process or solvent extraction could then be applied to recover HMs from the enriched leachate. Ongoing development of TS and bioleaching technologies could reduce the treatment cost or time.

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Effect of silica fume on the mechanical property and hydration characteristic of alkali-activated municipal solid waste incinerator (MSWI) fly ash

Journal of Cleaner Production ◽

10.1016/j.jclepro.2021.126317 ◽

2021 ◽

Vol 295 ◽

pp. 126317

Author(s):

Jun Ren ◽

Lu Hu ◽

Zhijun Dong ◽

Luping Tang ◽

Feng Xing ◽

...

Keyword(s):

Mechanical Property ◽

Fly Ash ◽

Municipal Solid Waste ◽

Silica Fume ◽

Waste Incinerator ◽

Municipal Solid Waste Incinerator ◽

Mswi Fly Ash ◽

Solid Waste Incinerator ◽

Alkali Activated ◽

Hydration Characteristic

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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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