scholarly journals Valorization of MSWI Bottom Ash as a Function of Particle Size Distribution, Using Steam Washing

2020 ◽  
Vol 12 (22) ◽  
pp. 9461
Author(s):  
Enrico Destefanis ◽  
Caterina Caviglia ◽  
Davide Bernasconi ◽  
Erica Bicchi ◽  
Renato Boero ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Particle Size ◽  
Bottom Ash ◽  
Raw Material ◽  
Size Classes ◽  
Mswi Bottom Ash ◽  
Legal Limits ◽  
Chloride Sulfate ◽  
Particle Size Classes ◽  
By Products

Treatments to reduce the leaching of contaminants (chloride, sulfate, heavy metals) into the environment from bottom ash (BA) are investigated, as a function of the ash’s particle size (s). The aim is to make BA suitable for reuse as secondary raw material, in accordance with the legal requirements. Such treatments must be economically feasible and, possibly, have to use by-products of the plant (in this case, steam in excess from the turbine). For the sake of completeness and comparison, carbonation is performed on those BA particle size classes that are not positively responsive to steam washing. BA is partitioned into four different particle size classes (s ≥ 4.75, 4.75 > s ≥ 2, 2 > s ≥ 1 and s < 1 mm, corresponding to 36, 24, 13 and 27 wt%, respectively). In the case of s ≥ 2 mm (60 wt%), steam washing is effective in reducing to under the legal limits the leaching of chlorides, sulfate and heavy metals (Zn, Cu, Cd, Pb). It has been observed that steam washing causes both removal and dissolution of thin dust adherent to the BA’s surface. BA with 2 > s ≥ 1 (~13 wt% of total BA) requires a combination of steam washing and carbonation to achieve a leaching below the legal limits. The finest BA fraction, s < 1 mm (~27 wt% of total BA), is treated by carbonation, which reduces heavy metals leaching by 85%, but it fails to sufficiently curb chlorides and sulfates.

scholarly journals ANTIMONY AND VANADIUM IN INCINERATION BOTTOM ASH – LEACHING BEHAVIOR AND CONCLUSIONS FOR TREATMENT PROCESSES

Detritus ◽  
2021 ◽  
pp. 75-81
Author(s):  
Franz-Georg Simon ◽  
Christian Vogel ◽  
Ute Kalbe
Keyword(s):  
Heavy Metals ◽  
Building Materials ◽  
Bottom Ash ◽  
Road Construction ◽  
Raw Material ◽  
Steady Increase ◽  
Leaching Behavior ◽  
Test Procedures ◽  
Chloride Sulfate ◽  
The Impact

Due to its large mineral fraction, incineration bottom ash (IBA) from municipal solid waste incineration is an interesting raw material that can be used for road construction or to produce secondary building materials. However, leaching chloride, sulfate, and potentially harmful heavy metals may cause problems in using IBA in civil engineering. Investigating leaching behavior is crucial for the assessment of the environmental compatibility of IBA applications. Various test procedures are available for that purpose. In the present study, a long-term leaching test of a wet-mechanically treated IBA was performed in a lysimeter for almost six years. While concentrations of chloride, sulfate and the majority of the heavy metals started to decrease rapidly with advancing liquid-to-solid ratio (L/S), antimony (Sb) and vanadium (V) behaved differently. At the beginning of the lysimeter test, the Sb and V concentrations were low, but after approximately one year of operation at an L/S ratio of around 0.8 L/kg, a steady increase was observed. It was shown that this increase is the result of low Ca concentrations due to the formation of CaCO3. With the data, the solubility products from Ca-antimonate and Ca-vanadate were calculated. The unusual leaching behavior of Sb and V should be kept in mind when considering field scenarios and evaluating the impact on the environment.

Heavy Metals Leaching of MSWI Bottom Ash: Effect of Short-term Natural Weathering

2017 ◽  
Author(s):  
Jurgita Seniunaitė ◽  
Saulius Vasarevičius
Keyword(s):  
Heavy Metals ◽  
Bottom Ash ◽  
Atmospheric Precipitation ◽  
Soil Surface ◽  
Natural Weathering ◽  
Short Term ◽  
Municipal Solid Wastes ◽  
Mswi Bottom Ash ◽  
Spectral Analysis Method ◽  
By Products

Municipal solid wastes incineration (MSWI) is an important part of the waste management systems in many European countries. Incineration process generates two main by-products: fly ash (FA) and bottom ash (BA). Bottom ash is composed of a variety of oxides, heavy metals and salts. Landfilling of untreated (fresh) BA can cause soil, surface and ground water contamination problems, because atmospheric precipitation in BA formed leachate, which contains of various materials. In this study investigates the influence of natural weathering to heavy metals leaching from BA. Leaching tests of bottom ash were carried out in 6 months, leachate samples were taken at 12 times (every 2 weeks). Heavy metals (Pb, Cu) concentrations were determined by atomic adsorption of spectral analysis method. The research shown, that the highest lead and copper concentration was determinated in 2 weeks weathered bottom ash leachate, respectively was 0.613 mg l–1 and 0.068 mg l–1. In both cases the concentration of Pb (0.010–0.052 mg l–1) and Cu (0.010-0.018 mg l–1) became almost stable after 12 weeks. Can be concluded, that short-term (3 months) natural weathering is sufficient time for stabilise MSWI bottom ash and heavy metals (Cu and Pb) leaching. After 18–24 weeks heavy metals concentrations stabilized and remained almost constant.

Use of Municipal Solid Waste Incineration Bottom Ash in Adsorption of Heavy Metals

2011 ◽  
Vol 474-476 ◽  
pp. 1099-1102
Author(s):  
Hai Ying Zhang ◽  
Yi Zheng ◽  
Hong Tao Hu ◽  
Jing Yu Qi
Keyword(s):  
Heavy Metals ◽  
Particle Size ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Residence Time ◽  
Bottom Ash ◽  
Waste Incineration ◽  
Synthetic Wastewater ◽  
High Porosity ◽  
Municipal Solid Waste Incineration

Bottom ash from municipal solid waste incineration (MSWI) has been previously suggested as an adsorbent for removing heavy metals from wastewater due to its high porosity and large surface area. In this study the adsorption characteristics of heavy metals were investigated using various particle sizes of MSWI bottom ash. The adsorption experiment was conducted using synthetic wastewater containing Cu, Zn, Pb and Cd as a function of residence time, initial pH, ash dosage and particle size, respectively. The adsorption rate increased with decreasing particle size and with increasing residence time. Through the above analysis, this work proved that bottom ash was effective in adsorbing the four heavy metals.

Effect on Compressive Strength by Mixing Ratio of MSWI Melting Slag/Bottom Ash

2009 ◽  
Vol 620-622 ◽  
pp. 631-634
Author(s):  
Woo Keun Lee ◽  
Eun Zoo Park ◽  
Ji Hyeon Lee ◽  
Yeong Seok Yoo
Keyword(s):  
Crystal Structure ◽  
Heavy Metals ◽  
Compressive Strength ◽  
Bottom Ash ◽  
Environmental Safety ◽  
Resource Conservation ◽  
Leaching Test ◽  
Mixing Ratio ◽  
Mswi Bottom Ash ◽  
Melting Slag

In this work, inorganic paste was made from melting slag (MS) of MSWI ash and MSWI bottom ash (MBA) by geopolymer technique. Heavy metals such as Pb and Cu are highly contained in MBA. In the view of environmental protection and resource conservation, recycling of MSWI ash is desirable. MS and MBA were mixed to make inorganic paste. Compressive strength was measured to evaluate the characteristics of inorganic paste after the period of 1, 3 and 7day. Compressive strength of almost 90 MPa was obtained at the mixing ratio of MS : MBA = 9 : 1. And the crystalloid and crystal structure was analyzed by FTIR and XRD. Korea Standard leaching Test (KSLT) is also used to evaluate the environmental safety of inorganic paste. The leached concentration of Pb and Cu were 0.44 ppm and 0.15 ppm, respectively. According to this result, heavy metals were safety immobilized and stabilized.

Modelling the influence of total suspended solids on E. coli removal in river water

2015 ◽  
Vol 73 (6) ◽  
pp. 1320-1332 ◽  
Author(s):  
Jueying Qian ◽  
Evelyn Walters ◽  
Peter Rutschmann ◽  
Michael Wagner ◽  
Harald Horn
Keyword(s):  
Particle Size ◽  
Large Scale ◽  
Suspended Solids ◽  
Total Suspended Solids ◽  
Sensitivity Coefficient ◽  
Fecal Indicator ◽  
E Coli ◽  
Size Classes ◽  
Sedimentation Process ◽  
Particle Size Classes

Following sewer overflows, fecal indicator bacteria enter surface waters and may experience different lysis or growth processes. A 1D mathematical model was developed to predict total suspended solids (TSS) and Escherichia coli concentrations based on field measurements in a large-scale flume system simulating a combined sewer overflow. The removal mechanisms of natural inactivation, UV inactivation, and sedimentation were modelled. For the sedimentation process, one, two or three particle size classes were incorporated separately into the model. Moreover, the UV sensitivity coefficient α and natural inactivation coefficient kd were both formulated as functions of TSS concentration. It was observed that the E. coli removal was predicted more accurately by incorporating two particle size classes. However, addition of a third particle size class only improved the model slightly. When α and kd were allowed to vary with the TSS concentration, the model was able to predict E. coli fate and transport at different TSS concentrations accurately and flexibly. A sensitivity analysis revealed that the mechanisms of UV and natural inactivation were more influential at low TSS concentrations, whereas the sedimentation process became more important at elevated TSS concentrations.

Effects of Metakoalin on Municipal Solid Waste Incineration (MSWI) Bottom Ash-Cement Composite

2020 ◽  
Vol 1010 ◽  
pp. 653-658
Author(s):  
Roshazita Che Amat ◽  
Khairul Nizar Ismail ◽  
Khairel Rafezi Ahmad ◽  
Norlia Mohamad Ibrahim
Keyword(s):  
Municipal Solid Waste ◽  
Solid Waste ◽  
Bottom Ash ◽  
Blended Cement ◽  
Waste Incineration ◽  
Cement Composite ◽  
Municipal Solid Waste Incineration ◽  
Mswi Bottom Ash ◽  
Waste Incinerators ◽  
By Products

Municipal solid waste incinerators (MSWI) produce by products which can be classified as bottom and fly ashes. The bottom ash accounts for 85-90 % of solid product resulting from MSW combustion. The objective of this study was to assess the feasibility of application of municipal solid waste incineration (MSWI) bottom ash as a supplementary cementations material for the preparation of blended cement. The used of bottom ash as a research material is caused by substances contained in cement is almost the same with bottom ash. Bottom ash was found to have some reactivity, but without greatly affecting the hydration process of OPC at 10 % replacement with 10% metakaolin is required to be used in the production of concrete in order to improve strength.

Material characterization of the MSWI bottom ash as a function of particle size. Effects of glass recycling over time

2017 ◽  
Vol 581-582 ◽  
pp. 897-905 ◽  
Author(s):  
R. del Valle-Zermeño ◽  
J. Gómez-Manrique ◽  
J. Giro-Paloma ◽  
J. Formosa ◽  
J.M. Chimenos
Keyword(s):  
Particle Size ◽  
Size Effects ◽  
Material Characterization ◽  
Bottom Ash ◽  
Particle Size Effects ◽  
Mswi Bottom Ash ◽  
Glass Recycling ◽  
Over Time

Environmental managing of bottom ashes from municipal thermovalorization waste for civil applications, as a function of particle size, based on steam washing

2020 ◽  
Author(s):  
Caterina Caviglia ◽  
Enrico Destefanis ◽  
Davide Bernasconi ◽  
Linda Pastero ◽  
Giorgia Confalonieri ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Particle Size ◽  
Natural Resources ◽  
Raw Materials ◽  
Chemical Species ◽  
Waste Incineration ◽  
Raw Material ◽  
Accelerated Carbonation ◽  
Washing Process ◽  
High Concentrations

&lt;p&gt;Nowadays, the production of constructional materials requires raw materials obtained through extractive activities that often imply different environmental impacts. In a perspective of a growing sensitivity towards a responsible use of natural resources the attention to materials coming from waste is focused. The waste from the municipal thermovalorization plants can be suitable for this applications, and after moderate and sustainable treatments, can find a role of raw material-second in the construction of works, reducing the need to find additional natural resources and related problems for disposal or storage. The present study aims to explore the possibility of promoting inertization (i.e. reducing the BA&amp;#8217;s release in water of environmentally dangerous chemical species below the legal thresholds) of as large a fraction of BA as possible, using ashes from one of the municipal waste incineration plants of Northern Italy, and exploiting byproducts of the incineration cycle, i.e. the spared steam from turbines, which produce electricity, and carbon dioxide from combustion fumes. The treatments discussed are as a function of the particle size (s). &amp;#160;BA are partitioned into three main classes, determined by previous studies s &amp;#8805; 4.75, 4.75 &gt; s &amp;#8805; 1, s &lt; 1 mm; %. The BA fraction with 4.75 &gt; s &amp;#8805; 1 mm was further divided into two portions to optimize the steam washing process: 4.75 &gt; s &amp;#8805; 2 mm and&amp;#160; 2 &gt; s &amp;#8805; 1 mm. BA with s &gt; 4.75 mm are treated with steam washing only. In fact, although they do not contain high concentrations of heavy metals, they largely surpass the Italian legislation thresholds related to the occurrence of chlorides and sulfates. Steam is generally available from modern incineration plants in a considerable amount, and it is more effective than water in removing a variety of impurities/low-crystallinity fragments from the surface of coarse grains. Inertization of BA with 4.75 &gt; s &amp;#8805; 1 is investigated by means of both steam washing and accelerated carbonation, to optimize the combination of these methods and expand as much as possible the s-range that requires steam washing only.&amp;#160; As to the BA fraction with s &lt; 1 mm, whose heavy metals content is likely larger than elsewhere, steam washing is of difficult application and therefore we resort to accelerated carbonation.&lt;/p&gt;

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