Application of Dechlorinated MSWI Fly Ash in Asphalt Mixtures

2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Hu T ◽  
◽  
Zhao K ◽  
Chen D ◽  
Hu Y ◽  
...  
Keyword(s):  
Fly Ash ◽  
Waste Incineration ◽  
Environmental Risks ◽  
Asphalt Mixtures ◽  
Municipal Solid Waste Incineration ◽  
Mswi Fly Ash ◽  
Water Absorption Coefficient ◽  
Leaching Toxicity ◽  
Application Requirements ◽  
Marshall Stability

The application of Municipal Solid Waste Incineration (MSWI) fly ash in asphalt mixtures is an efficient way to utilize fly ash. The feasibility of applying various kinds of dechlorinated fly ash in asphalt mixtures was comprehensively discussed in the study. The effects of types and amounts of dechlorinated fly ash on the performances of prepared asphalt mixtures were explored. Additionally, their environmental risks and economic values were further evaluated. The water absorption coefficient and porosity of fly ash-asphalt mixtures were respectively in the ranges of 0.15-0.5% and 3-4%, which met the application requirements of asphalt. The replacement of Raw Fly Ash (RFA) and Dechlorinated Fly Ash (DFA) improved Marshall stability, split strength, and Tensile Strength Ratio (TSR) of asphalt mixtures. DFA realized the more significant improvements. The leaching concentrations of heavy metals in all the prepared asphalt mixtures were lower than the detection limit, indicating that there was no risk of leaching toxicity.

Analysis of Heavy Metal Leaching in Fly Ash from One Shanghai Municipal Solid Waste Incineration (MSWI) Plant

2012 ◽  
Vol 531 ◽  
pp. 292-295
Author(s):  
Hai Ying Zhang ◽  
Guo Liang Yuan ◽  
Guo Xian Ma
Keyword(s):  
Heavy Metals ◽  
Fly Ash ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Hazardous Waste ◽  
Extraction Procedure ◽  
Waste Incineration ◽  
Municipal Solid Waste Incineration ◽  
Mswi Fly Ash ◽  
Leaching Toxicity

The characteristics and leaching behavior of heavy metals in fly ash, sampled from one MSWI (municipal solid waste incineration) plant in Shanghai China, were investigated. The results indicated that the main elements of fly ash were Fe, K, Na, Cl, Si, Ca, Al, and the total fraction of heavy metals was in the range of 0.8 % - 2.0%. Hence, MSWI fly ash was considered to be one kind of hazardous waste due to its potential environmental risk. Leaching toxicity was performed on fly ash samples from the MSWI plant in Shanghai China. Leaching toxicity of the heavy metals by the ALT (available leaching toxicity) procedure exceeded that by the HVEP (horizontal vibration extraction procedure) standard. Leaching concentrations of Ni, Zn, Cd and Pb exceeded the limit of hazardous waste identification standard. Hence, fly ash is a hazardous waste.

Safe Analysis of Construction Material after Being Sintered

2013 ◽  
Vol 849 ◽  
pp. 253-256
Author(s):  
Hai Ying Zhang ◽  
Shu Zhen Li
Keyword(s):  
Fly Ash ◽  
Construction Material ◽  
Extraction Procedure ◽  
Waste Incineration ◽  
Municipal Solid Waste Incineration ◽  
Mswi Fly Ash ◽  
Horizontal Vibration ◽  
Limit Value ◽  
Leaching Toxicity ◽  
Toxicity Analysis

In this work, leaching toxicity of MSWI (municipal solid waste incineration) fly ash by HVEP (horizontal vibration extraction procedure) and ALT (available leaching toxicity) as a function of temperature was analyzed. MSWI fly ash was firstly sintered at 700°C, 800°C, 900°C, 1,000°C and 1,100°C respectively for 30 minutes, and then underwent leaching toxicity analysis of heavy metals. It was found that leaching toxicity of the heavymetals in fly ash sintered at temperatures over 900°C is lower than the limit value described in Identification Standard of Hazardous WasteIdentification of Leaching Toxicity. Therefore, 1000°C is recommended to treat MSWI fly ash.

scholarly journals Seasonal Variation of the Mobility and Toxicity of Metals in Beijing’s Municipal Solid Waste Incineration Fly Ash

2021 ◽  
Vol 13 (12) ◽  
pp. 6532
Author(s):  
Hang Zhao ◽  
Yang Tian ◽  
Rong Wang ◽  
Rui Wang ◽  
Xiangfei Zeng ◽  
...  
Keyword(s):  
Fly Ash ◽  
Municipal Solid Waste ◽  
Sequential Extraction ◽  
Solid Waste ◽  
Waste Incineration ◽  
Metal Mobility ◽  
Municipal Solid Waste Incineration ◽  
Mswi Fly Ash ◽  
Leaching Toxicity ◽  
Sequential Extraction Procedures

Metal mobility and toxicity of the municipal solid waste incineration (MSWI) fly ash from different seasons in Beijing were studied using leaching toxicity procedures, sequential extraction procedures, and bioavailability procedures. The X-ray diffraction results showed that MSWI fly ash contained CaSO4, CaCO3, and KCl. The Pb, Zn, and Cd contents of MSWI fly ash were high, especially during autumn, being 42, 77, and 1260 times higher than that of their soil backgrounds, respectively. Leaching toxicity experiments showed that MSWI fly ash is hazardous, since Pb exceeded the maximum threshold (5 mg/L). The main alkali metal ions and anions, heavy metals total content, leaching concentration, chemical speciation, and bioavailability varied seasonally. The Pb and Zn leaching concentrations in summer and autumn were higher than that of the other two seasons. Sequential extraction procedures indicated that Pb, Zn, and Cd showed extremely high metal mobility, i.e., the residual states of Pb and Cd in spring were 5.83% and 1.21%, respectively, and that of Zn in autumn was 10.68%. These results will help industries, governments, and the public better understand the risk of MSWI fly ash and will urge them to pay more attention to preventing harm to the ecosystem and human beings.

Content Analysis of Heavy Metals in Fly Ash from One Shanghai Municipal Solid Waste Incineration (MSWI) Plant

2012 ◽  
Vol 531 ◽  
pp. 272-275 ◽  
Author(s):  
Hai Ying Zhang ◽  
Guo Xian Ma ◽  
Guo Liang Yuan
Keyword(s):  
Heavy Metals ◽  
Fly Ash ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Large Scale ◽  
Environmental Concern ◽  
Waste Incineration ◽  
Municipal Solid Waste Incineration ◽  
Mswi Fly Ash ◽  
Leaching Toxicity

The presence of heavy metals in municipal solid waste incineration (MSWI) fly ash is of environmental concern due to their leaching potential in landfill environments. Heavy metal content was performed on fly ash samples from a large-scale municipal solid waste incineration plant in Shanghai China. Content of heavy metals followed the decreasing sequence of Ni > Zn > Pb > Cu > Cd. As pollution of heavy metals is related to not only the content but also their leaching toxicity, further experiment of leaching concentrations of the metals is required to determine the seriousness of pollution caused by the heavy metals.

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

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.

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

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.

Leaching of Heavy Metals from Municipal Solid Waste Incineration (MSWI) Fly Ash Using Nitric Acid

2012 ◽  
Vol 249-250 ◽  
pp. 918-921 ◽  
Author(s):  
Hai Ying Zhang ◽  
Guo Xian Ma
Keyword(s):  
Heavy Metals ◽  
Fly Ash ◽  
Nitric Acid ◽  
Municipal Solid Waste ◽  
Waste Incineration ◽  
Acid Extraction ◽  
Municipal Solid Waste Incineration ◽  
Mswi Fly Ash ◽  
Removal Ratio ◽  
Solid Ratio

The presence of heavy metals in municipal solid waste incineration (MSWI) fly ash is of environmental concern due to their leaching potential in landfill environments. Acid extraction is a conventional method of safe treatment of fly ash. In this work, nitric acid was used as the extraction acid to leach Ni, Zn, Pb and Cu out from the ash. In addition, influence of nitric acid concentration and liquid to solid ratio on removal ratio of the four heavy metals was studied. It was found that removal ratio followed the decreasing sequence of Pb > Cd > Cu > Zn for acid extraction using nitric acid. The optimal extraction condition was 5.3 mol/L of nitric concentration at 20 liquid to solid ratio, which resulted in a removal ratio of 98% for Pb, 86% for Cd, around 73% for Cu and around 42% for Zn.

Sign in / Sign up

Export Citation Format

Share Document