Pozzolanic Reactivity of Coal Bottom Ash after Chemically Pre-Treated with Sulfuric Acid

2019 ◽  
Vol 947 ◽  
pp. 212-216
Author(s):  
Andri Kusbiantoro ◽  
Amalina Hanani ◽  
Rahimah Embong
Keyword(s):  
Construction Industry ◽  
Treatment Process ◽  
Current Trend ◽  
Bottom Ash ◽  
Supplementary Cementitious Materials ◽  
Strength Development ◽  
Coal Bottom Ash ◽  
Cement Replacement ◽  
Pozzolanic Reactivity ◽  
Pre Treatment

Current trend in construction industry has highlighted the use of silica-rich supplementary cementitious materials from industrial wastes in the production of concrete. Numerous studies have validated the pozzolanic properties of these materials, yet coal bottom ash received only infamous reputation as a pozzolanic material, owing to its low reactivity and heavy metals contaminants. Therefore this study was purposed to enhance the pozzolanic reactivity of coal bottom ash through chemical pre-treatment process. Different concentrations of acids and treatment period were studied to obtain optimum parameters for pre-treatment process. Treated ash was characterized for its chemical oxide composition. Its effect on the hydration of cement was studied through the inclusion as cement replacement material in mortar mixtures. From the chemical oxide compositions, a combination of 0.5 M of H2SO4 and 1 hour soaking duration presented the highest SiO2 proportion in the ash. Its inclusion at 5% (by weight of cement) to replace cement proportion in mortar mixtures was able to enhance the compressive strength of mortar at later age, regardless of its slower strength development in the early age. Utilizing treated coal bottom ash as partial cement replacement material has unlocked new achievement for greener future in construction industry.

Soluble Pozzolanic Materials from Coal Bottom Ash as Cement Replacement Material

2021 ◽  
Vol 879 ◽  
pp. 68-80
Author(s):  
Rahimah Embong ◽  
Andri Kusbiantoro ◽  
Azrina Abd Wahab ◽  
Khairunisa Muthusamy
Keyword(s):  
Industrial Waste ◽  
Bottom Ash ◽  
Cumulative Effect ◽  
Soluble Form ◽  
Recycling Rate ◽  
Strength Development ◽  
Coal Bottom Ash ◽  
Cement Replacement ◽  
Soluble Silica ◽  
Pozzolanic Materials

Nowadays, intensive research in production of highly reactive pozzolanic materials from industrial waste to replace cement is crucial. This action expected to increase industrial waste recycling rate and at the same time reduce extraction of non-renewable resources of limestone. Unique characteristics of coal bottom ash as one of the industrial based pozzolan gained less popularity because of its low reactivity and heavy metal leaching due to conventional method used for disposal. Therefore, an alternative approach was deliberated in this research to utilize coal bottom ash into soluble form and enhance the quality of bottom ash as pozzolanic material. Coal bottom ash after the acid washing with optimum parameter was then undergoes solution-gelification process with various alkali based solution for 2 hours soaking durations. The conversion of coal bottom ash into soluble silica in this study demonstrates good pozzolanic performance in a state of siliceous gel pozzolan compared to the raw ones. 5% of cement replacement by soluble silica from CBA shows good strength development from early and later age. The physical dispersion effect is the cumulative effect of enhancement cement hydration due to the availability of increased the nucleation sites on soluble silica particles.

scholarly journals A Review of the Utilization of Coal Bottom Ash (CBA) in the Construction Industry

2021 ◽  
Vol 13 (14) ◽  
pp. 8031
Author(s):  
Syakirah Afiza Mohammed ◽  
Suhana Koting ◽  
Herda Yati Binti Katman ◽  
Ali Mohammed Babalghaith ◽  
Muhamad Fazly Abdul Patah ◽  
...  
Keyword(s):  
Human Health ◽  
Construction Industry ◽  
Bottom Ash ◽  
High Volume ◽  
Coal Bottom Ash ◽  
Substitute Material ◽  
Physical And Chemical ◽  
Vast Range

One effective method to minimize the increasing cost in the construction industry is by using coal bottom ash waste as a substitute material. The high volume of coal bottom ash waste generated each year and the improper disposal methods have raised a grave pollution concern because of the harmful impact of the waste on the environment and human health. Recycling coal bottom ash is an effective way to reduce the problems associated with its disposal. This paper reviews the current physical and chemical and utilization of coal bottom ash as a substitute material in the construction industry. The main objective of this review is to highlight the potential of recycling bottom ash in the field of civil construction. This review encourages and promotes effective recycling of coal bottom ash and identifies the vast range of coal bottom ash applications in the construction industry.

PROPERTIES OF MORTAR CONTAINING CERAMIC POWDER WASTE AS CEMENT REPLACEMENT

2015 ◽  
Vol 77 (12) ◽  
Author(s):  
Mostafa Samadi ◽  
Mohd Warid Hussin ◽  
Han Seung Lee ◽  
Abdul Rahman Mohd Sam ◽  
Mohamed A. Ismail ◽  
...  
Keyword(s):  
Construction Industry ◽  
Ceramic Powder ◽  
Ceramic Materials ◽  
Strength Properties ◽  
Strength Development ◽  
X Ray Diffraction ◽  
Cement Replacement ◽  
Water Curing ◽  
Field Emission Electron Microscopy ◽  
Curing Regime

Ceramic materials are largely used in all over the world and consequently, large quantities of wastes are produced simultaneously by tile manufacturers and construction industry. Nevertheless, part of these wastes and those produced by the construction industry are dumped in landfills. This paper presents the effect of using ceramic waste in mortar as cement replacement. Four mortar mixes were prepared in this study and focuses on the effect of ceramic powder as cement replacement on the strength development and the morphology of the mortar. The microstructural characteristics of the mortar were investigated by scanning field emission electron microscopy (FESEM) and the mineralogical properties was investigated using the X-ray diffraction (XRD).  The cement was replaced by ceramic powder from 0% to 60% by weight of cement. The specimens were cast in 50 x 50 x 50 mm cube and water curing regime was used until the age of testing. The fineness of ceramic powder used is less than 45µm. The developments of compressive strength were studied for all samples. It is found that the optimum replacement that gave the highest strength was 40% replacement. It was also found that the use of ceramic powder enhanced the microstructure and strength properties of the mortar.

Tanjung Bin Coal Bottom Ash: From Waste to Concrete Material

2013 ◽  
Vol 705 ◽  
pp. 163-168 ◽  
Author(s):  
Abdulhameed Umar Abubakar ◽  
Khairul Salleh Baharudin
Keyword(s):  
Power Plant ◽  
Economic Value ◽  
Bottom Ash ◽  
Chemical Properties ◽  
Strength Development ◽  
Concrete Material ◽  
Coal Bottom Ash ◽  
Physical And Chemical ◽  
Ash Pond ◽  
And Chemical Properties

Coal Bottom Ash (CBA) is a by-product from the generation of electricity using pulverized coal; Tanjung Bin power plant in Malaysia is a coal-based power plant that generates tonnes of bottom ash daily without known economic value that ends up in the ash pond. Due to the problems associated with the disposal ash pond in terms of cost and environmental impact, attention has now been focused on how best to utilize this waste. This paper present the recent development achieved on the utilization of bottom ash from Tanjung Bin power plant Malaysia in concrete development; physical and chemical properties, workability and fresh concrete properties as well as the strength development of Tanjung Bin bottom ash.

scholarly journals Effects of Microwave Energy on Fast Compressive Strength Development of Coal Bottom Ash-Based Geopolymers

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sungil Hong ◽  
Hyo Kim
Keyword(s):  
Compressive Strength ◽  
Moisture Content ◽  
Structural Integrity ◽  
Bottom Ash ◽  
Free Water ◽  
Strength Loss ◽  
Microwave Energy ◽  
Strength Development ◽  
Coal Bottom Ash ◽  
Effective Manner

Abstract Microwave energy has been shown to be effective for geopolymer synthesis due to its fast and penetrative heating characteristics; however, the changes in the physicochemical properties of the geopolymer, resulting from the microwave irradiation, have not been fully elucidated. Therefore, this study is aimed at investigating the effect of the microwaving on the properties of coal bottom ash(CBA) geopolymers. We prepared geopolymer samples by casting a mixture of ground CBA and 14 M NaOH solution against cubic molds with a hand press machine, followed by pre-curing in a dry oven at 75 °C for 24 h and microwaving under various powers and durations. The compressive strength strongly depended on the moisture content, i.e., the strength increased from 21 to 65 MPa or higher as the moisture content decreased to critical values, after which the strength began to decrease. The results showed that microwave energy stimulated an additional geopolymerization by evaporating the redundant free water. This led to the strength gain, although the over-irradiation generated a high internal stress and poor structural integrity, which resulted in the strength loss. Therefore, the appropriate application of microwave energy is a promising option for synthesizing high-strength geopolymers in a cost- and time-effective manner.

scholarly journals Strength Properties of Untreated Coal Bottom Ash as Cement Replacement

2020 ◽  
Vol 6 (1) ◽  
pp. 13 ◽  
Author(s):  
Noraziela Syahira Baco ◽  
Shahiron Shahidan ◽  
Sharifah Salwa Mohd Zuki ◽  
Noorwirdawati Ali ◽  
Mohamad Azim Mohammad Azmi
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Bottom Ash ◽  
Strength Test ◽  
Splitting Tensile Strength ◽  
Curing Time ◽  
Coal Bottom Ash ◽  
Cement Replacement ◽  
Tensile Strength Test ◽  
Compressive Strength Test

Coal Bottom Ash (CBA) is a mineral by-product of thermal power plants obtained from the combustion of coal. In many countries, CBA wastes are identified as hazardous materials. The utilization of CBA can help in alleviating environmental problems; thus, this research was carried out to explore the possibility of its use as cement replacement in concrete manufacturing. Presently, In Malaysia, research that concerns about the use of CBA as cement replacement is very limited. Therefore, this study was aimed to investigate the properties of CBA as cement replacement and to identify the optimum percentage of untreated CBA as cement replacement. The CBA used in this study were taken from the Tanjung Bin power plant. In this research, the amount of CBA in the concrete mixture varied from 20% to 40% to replace cement. The properties of concrete containing CBA as cement replacement was examined through slump test, sieve analysis, concrete compressive strength test and splitting tensile strength test. The compressive strength test and splitting tensile strength test were performed at 7 and 28 days of curing time. Based on this research, it can be concluded that the optimum percentage of CBA as cement replacement is 25% for a curing time of both 7 and 28 days with the concrete compression strength of 45.2 MPa and 54.6 MPa, respectively. Besides, the optimum percentage for tensile strength is also at 25% CBA for a curing period of both 7 and 28 days with the tensile strength of 2.91 MPa and 3.28 MPa, respectively. 

scholarly journals Sulfation–Roasting–Leaching–Precipitation Processes for Selective Recovery of Erbium from Bottom Ash

2019 ◽  
Vol 11 (12) ◽  
pp. 3461 ◽  
Author(s):  
Josiane Ponou ◽  
Marisol Garrouste ◽  
Gjergj Dodbiba ◽  
Toyohisa Fujita ◽  
Ji-Whan Ahn
Keyword(s):  
Room Temperature ◽  
Treatment Process ◽  
Bottom Ash ◽  
Ammonium Oxalate ◽  
Optimal Conditions ◽  
Selective Recovery ◽  
Sulfation Roasting ◽  
Roasting Temperature ◽  
Pre Treatment ◽  
H 30

Bottom ash (BA) is mainly composed of compounds of Al, Fe, Ca, and traces of rare earth elements (REEs). In this study, the selective recovery of erbium (Er) as REEs by means of sulfation–roasting–leaching–precipitation (SRLP) using BA was investigated. A pre-treatment process of sulfation and roasting of BA was developed to selectively recover REEs using ammonium oxalate leaching (AOL) followed by precipitation. Most of the oxides were converted to their respective sulfates during sulfation. By roasting, unstable sulfates (mostly iron) decomposed into oxides, while the REE sulfates remained stable. Roasting above 600 °C induces the formation of oxy-sulfates that are almost insoluble during AOL. Dissolved REEs precipitate after 7 days at room temperature. The effects of particle size, roasting temperature, leaching time, and AOL concentration were the important parameters studied. The optimal conditions of +100–500 μm particles roasted at 500 °C were found to leach 36.15% of total REEs in 2 h 30 min and 94.24% of the leached REEs were recovered by precipitation. A total of 97.21% of Fe and 94.13% of Al could be separated from Er.

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