Advances in Coal Bottom Ash Use as a New Common Portland Cement Constituent

Coal fly ash (CFA), coal bottom ash (CBA) are residues produced in thermo-electrical power stations as result of the coal combustion in the same boiler. Therefore, some characteristics of the coal fly ash (CFA) are comparable with those of the coal bottom ash (CBA). Nevertheless, coal bottom ash size is larger than coal fly ash one. Consequently, it was found that it is necessary to grind the coal bottom ash (CBA) to reach a similar size to that one of the CFA. The objective of this paper is to evaluate the performance of Portland cement mortars made with coal fly ash (CFA), coal bottom ash (CBA) or mixes (CFA+CBA), against sulphate attack. The methodology is based on the expansion of slender bars submerged in a sodium sulphate solution (5%) according to the ASTM C-1012/C1012-13 standard. It has been found that mortars elaborated with CEM I 42.5 N (without ashes) presented the largest expansion (0.09%) after a testing period of 330 days. Mortars made with CEM II/A-V exhibited lower expansion (0.03%). Summing up, it can be established that mortar expansion decreases when the coal ash amount increases, independently of the type of coal ash employed. The novelty of this paper relies on the comparison between the performances of Portland cement mortars made with coal fly ash (CFA) or coal bottom ash (CBA) exposed to external sulphate attack. Doi: 10.28991/cej-2021-03091640 Full Text: PDF

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Influence of Coal Bottom Ash on Properties of Portland cement Mortar

International Journal of Integrated Engineering ◽

10.30880/ijie.2019.11.02.008 ◽

2019 ◽

Vol 11 (2) ◽

Cited By ~ 1

Author(s):

Ali Huddin Ibrahim ◽

◽

Choong Kok Keong ◽

Megat Azmi Megat Johari ◽

Mohamad Rohaidzat Mohamed Rashid ◽

...

Keyword(s):

Portland Cement ◽

Cement Mortar ◽

Bottom Ash ◽

Coal Bottom Ash

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An investigation on the use of tincal ore waste, fly ash, and coal bottom ash as Portland cement replacement materials

Cement and Concrete Research ◽

10.1016/s0008-8846(01)00661-5 ◽

2002 ◽

Vol 32 (2) ◽

pp. 227-232 ◽

Cited By ~ 61

Author(s):

I Kula ◽

A Olgun ◽

V Sevinc ◽

Y Erdogan

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Bottom Ash ◽

Coal Bottom Ash ◽

Cement Replacement

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Recycling Untreated Coal Bottom Ash with Added Value for Mitigating Alkali–Silica Reaction in Concrete: A Sustainable Approach

Sustainability ◽

10.3390/su122410631 ◽

2020 ◽

Vol 12 (24) ◽

pp. 10631

Author(s):

Safeer Abbas ◽

Uzair Arshad ◽

Wasim Abbass ◽

Moncef L. Nehdi ◽

Ali Ahmed

Keyword(s):

Portland Cement ◽

Power Plants ◽

Activity Index ◽

Bottom Ash ◽

Pozzolanic Activity ◽

Added Value ◽

Partial Replacement ◽

Alkali Silica Reaction ◽

Coal Bottom Ash ◽

Limit Value

Each year, about 730 million tons of bottom ash is generated in coal fired power plants worldwide. This by-product can be used as partial replacement for Portland cement, favoring resource conservation and sustainability. Substantial research has explored treated and processed coal bottom ash (CBA) for possible use in the construction industry. The present research explores using local untreated and raw CBA in mitigating the alkali–silica reaction (ASR) of reactive aggregates in concrete. Mortar bar specimens incorporating various proportions of untreated CBA were tested in accordance with ASTM C1260 up to 150 days. Strength activity index (SAI) and thermal analysis were used to assess the pozzolanic activity of CBA. Specimens incorporating 20% CBA achieved SAI greater than 75%, indicating pozzolanic activity. Mixtures incorporating CBA had decreased ASR expansion. Incorporating 20% CBA in mixtures yielded 28-day ASR expansion of less than the ASTM C1260 limit value of 0.20%. Scanning electron microscopy depicted ASR induced microcracks in control specimens, while specimens incorporating CBA exhibited no microcracking. Moreover, low calcium-to-silica ratio and reduced alkali content were observed in specimens incorporating CBA owing to alkali dilution and absorption, consequently decreasing ASR expansion. The toxicity characteristics of CBA indicated the presence of heavy metals below the US-EPA limits. Therefore, using local untreated CBA in concrete as partial replacement for Portland cement can be a non-hazardous alternative for reducing the environmental overburden of cement production and CBA disposal, with the added benefit of mitigating ASR expansion and its associated costly damage, leading to sustainable infrastructure.

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Effects of Coal Bottom Ash on the Compressive Strength of Portland Cement Mortar

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.802.149 ◽

2015 ◽

Vol 802 ◽

pp. 149-154 ◽

Cited By ~ 1

Author(s):

Ali Huddin Ibrahim ◽

Kok Keong Choong ◽

Megat Azmi Megat Johari ◽

Shahril Izham Md Noor ◽

Nur Liyana Zainal ◽

...

Keyword(s):

Compressive Strength ◽

Portland Cement ◽

Cement Mortar ◽

Bottom Ash ◽

Unburned Carbon ◽

Partial Replacement ◽

Chemical Compositions ◽

Coal Bottom Ash ◽

Compressive Strength Test ◽

Pozzolanic Properties

The possibility of utilizing treated coal bottom ash as a partial replacement of Portland cement was examined through compressive strength test on mortar samples. A total of 16 batches of mortar mixtures with cement:sand ratio of 1:2.5 and 1:2.75 were prepared using two types of treated coal bottom ash. The chemical compositions including the unburned carbon of coal bottom ash were also analyzed. In order to remove the excess unburned carbon which will affect the potential pozzolanic properties, the coal bottom ash was heated at 550 ± 50oC and 700 ± 50°C for 60 min in an electrical furnace.The results showed that compressive strength of mortar mixtures with cement:sand ratio of 1:2.5 and 1:2.75 containing treated coal bottom ash which was heated at 550oC results in an increase in compressive strength. At 10% and 20% of treated coal bottom ash replacement levels to Portland cement, the compressive strength of the mortar mixture was significantly improved at the age of 28 days. The compressive strength of the mortar mixtures at early ages gives lower strength as compared to the plain Portland cement mortar. However, the effect of treated coal bottom ash that was heated at 700°C is to reduce the compressive strength of the mortar mixtures except for mixture with cement:sand ratio of 1:2.5 containing 10% coal bottom ash at 56 days.

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Effect of Local Metakaolin Developed from Natural Material Soorh and Coal Bottom Ash on Fresh, Hardened Properties and Embodied Carbon of Self-Compacting Concrete

10.21203/rs.3.rs-427666/v1 ◽

2021 ◽

Author(s):

Manthar Ali Keerio ◽

Abdullah Saand ◽

Aneel Kumar ◽

Naraindas Bheel ◽

Karm Ali

Keyword(s):

Portland Cement ◽

Fresh Concrete ◽

Bottom Ash ◽

Partial Replacement ◽

Experimental Program ◽

Natural Material ◽

Fine Aggregate ◽

Self Compacting Concrete ◽

Coal Bottom Ash ◽

Hardened Properties

Abstract The carbon dioxide emissions from Portland cement production have increased significantly and Portland cement is the main binder used in self-compacting concrete, so there is an urgent need to find environmental friendly materials as alternative resources. In most developing countries, the availability of huge amounts of agricultural waste has paved the way for studying how these materials can be processed into self-compacting concrete as binder and aggregates compositions. Therefore, this experimental program was carried out to study the properties of self-compacting concrete (SCC) made with local metakaolin, coal bottom ash separately and combined. Total 25 mixes were prepared with four mixes as 5,10, 15 and 20% replacement of cement with metakaolin, four mixes as 10, 20, 30 and 40% of coal bottom ash as partial replacement of fine aggregates separately and 16 mixes prepared combined with metakaolin and coal bottom ash. The fresh properties were explored by slump flow, T50 flow, V-funnel, L-box, J-Ring sieve segregation test. Moreover, the hardened properties of concrete were performed for compressive, splitting tensile and flexural strength and permeability of SCC mixtures. Fresh concrete test results show that even if no viscosity modifier is required, satisfactory fresh concrete properties of SCC can be obtained by replacing the fine aggregate with coal bottom ash content. At 15% replacement of cement with local metakaolin is optimum and gave better results as compared to control SCC. At 30% replacement of fine aggregate is optimum and gave better results as compared to control SCC. In the combined mix 10% replacement of cement with metakaolin combined with 30% replacement of fine aggregate with coal bottom ash is optimum and gave better results as compared to control SCC.

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Recent Advances in Coal Bottom Ash Use as a New Common Portland Cement Constituent

Structural Engineering International ◽

10.2749/101686613x13768348400518 ◽

2014 ◽

Vol 24 (4) ◽

pp. 503-508 ◽

Cited By ~ 5

Author(s):

Cristina Argiz ◽

Esperanza Menéndez ◽

Amparo Moragues ◽

Miguel Ángel Sanjuán

Keyword(s):

Portland Cement ◽

Bottom Ash ◽

Coal Bottom Ash ◽

Recent Advances

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Coal Bottom Ash for Portland Cement Production

Advances in Materials Science and Engineering ◽

10.1155/2017/6068286 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 16

Author(s):

Cristina Argiz ◽

Miguel Ángel Sanjuán ◽

Esperanza Menéndez

Keyword(s):

Chemical Composition ◽

Power Plant ◽

Portland Cement ◽

Electrical Power ◽

Bottom Ash ◽

Point Of View ◽

Raw Material ◽

Reaction Products ◽

Cement Production ◽

Coal Bottom Ash

Because of industrialization growth, the amount of coal power plant wastes has increased very rapidly. Particularly, the disposal of coal bottom ash (CBA) is becoming an increasing concern for many countries because of the increasing volume generated, the costs of operating landfill sites, and its potential hazardous effects. Therefore, new applications of coal bottom ash (CBA) have become an interesting alternative to disposal. For instance, it could be used as a Portland cement constituent leading to more sustainable cement production by lowering energy consumption and raw material extracted from quarries. Coal fly and bottom ashes are formed together in the same boiler; however, the size and shape of these ashes are very different, and hence their effect on the chemical composition as well as on the mineralogical phases must be studied. Coal bottom ash was ground. Later, both ashes were compared from a physical, mechanical, and chemical point of view to evaluate the potential use of coal bottom ash as a new Portland cement constituent. Both ashes, produced by the same electrical power plant, generally present similar chemical composition and compressive strength and contribute to the refill of mortar capillary pores with the reaction products leading to a redistribution of the pore size.

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