scholarly journals Effect of Calcination on the Chemical and Microstructural Properties of Rice Husk Ash

2021 ◽  
pp. 81-87
Author(s):  
Khalil Ur Rehman ◽  
Afaq Ahmad ◽  
Fawad Ahmad ◽  
Ezaz Ali Khan ◽  
Muhammad Armaghan Siffat
Keyword(s):  
Rice Husk ◽  
Research Study ◽  
Rice Husk Ash ◽  
Amorphous Material ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Microstructural Properties ◽  
X Ray ◽  
Calcination Temperatures ◽  
Concrete Production

This research study is aimed to evaluate the effects of different calcination temperatures on the properties of rice husk ash such as the chemical and microstructural properties. Rice husk ash is not utilized properly; it is not dumped with proper handling which is also causing environmental issues. Currently researchers are working on supplementary cementitious materials in concrete, in light of which, this research study is aimed to evaluate the effects of burning on Rics Husk Ash (RHA) structure and its pozzolanic reactivity for utilizing it in concrete. The rice husk is burnt at temperatures of 600-800°C for a duration of 8, 16 and 24 hours and for evaluating different chemical and structural properties through tests of X-ray Diffraction (XRD), X-Ray fluorescence (XRF) and Fourier Transform Infrared Spectroscopy (FTIR). It is concluded that burning of rice husk at 600-800°C for duration of 24 hours gives us more reactive and amorphous material and can be used as a cement substitute for sustainable concrete production.

scholarly journals Measurement of Pozzolanic Activity Index of Scoria, Pumice, and Rice Husk Ash as Potential Supplementary Cementitious Materials for Portland Cement

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Hieronimi A. Mboya ◽  
Cecil K. King’ondu ◽  
Karoli N. Njau ◽  
Alex L. Mrema
Keyword(s):  
Portland Cement ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Activity Index ◽  
Cementitious Materials ◽  
Pozzolanic Activity ◽  
Supplementary Cementitious Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Setting Times

This work investigated the properties of scoria and pumice as supplementary cementitious materials (SCMs) for Portland cement and compared to those of rice husk ash (RHA). X-ray fluorescence, X-ray diffraction, and pozzolanic activity index (PAI) tests confirmed the suitability of these two materials as potential SCMs. Scoria and RHA samples achieved over 75% PAI at 7 days whereas pumice did this after 28 days. Initial and final mean setting times observed for the composite cement blended with these materials were 166 and 285 min, respectively. These setting times are longer than that of ordinary Portland cement but shorter compared to that of common Portland pozzolana cement. The ultimate mean compressive strengths achieved at 28 days of curing were 42.5, 44.8, and 43.0 MPa for scoria, pumice, and RHA, respectively, signifying that these materials are good SCMs. Higher fineness yielded higher ultimate mean strength. For instance, a scoria sample with a fineness of 575 m2/kg achieved the strength of 52.2 MPa after 28 days.

scholarly journals Influence of Rice Husk Ash Density on the Workability and Strength of Structural Concrete

2017 ◽  
Vol 2 (3) ◽  
pp. 36 ◽  
Author(s):  
John Kamau ◽  
Ash Ahmed ◽  
Fraser Hyndman ◽  
Paul Hirst ◽  
Joseph Kangwa
Keyword(s):  
Compressive Strength ◽  
Rice Husk ◽  
Water Demand ◽  
Rice Husk Ash ◽  
Concrete Strength ◽  
High Water ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Hardened Concrete ◽  
Structural Applications

Supplementary cementitious materials (SCMs) have been known to improve the properties of fresh and hardened concrete, and at the same time enhance the sustainability of concrete. Rice husk Ash (RHA), is one such material, but has neither been widely studied nor applied in practice. This work investigated the effect of the density of RHA on the workability and compressive strength of fresh and hardened RHA-replaced concrete respectively. Cement was replaced with RHA in concrete by weight (RHA-W) and by volume (RHA-V) at steps of 0%, 5%, 7.5%, 10%, 15%, 20%, 25% and 30%. The 0% replacement was used as the reference point from which performances were measured. Results showed that unlike the characteristic of other established pozzolans, RHA significantly reduced the workability of wet concrete and the rate of compressive strength gain over curing time due to a high water demand that is caused by the increased volume of replaced concrete, which results from its low density. Workability reduced with increased replacement for both RHA-W and RHA-V. Replacements of above 15% were not possible for the RHA-W due to the high water demand. However, replacements of up to 30% were achieved for the RHA-V. RHA-W specimens achieved lower compressive strengths and were observed to gain strength at a lower rate over the 28 to 91-days period of curing compared to RHA-V specimens. This behavior was attributed to the shortage of water that is necessary for the hydration of cement and subsequent pozzolanic reaction, which is the basis of the contribution that is made to the strength and performance of concrete by SCMs. However, the compressive strengths achieved were above the study’s target concrete strength of class C32/40 at 91 days, which is among those classes that are listed as being durable and suitable for structural applications. A conclusion that RHA should supplement cements by volumetric replacement rather than simple substitution by weight was drawn.

Rice Husk Ash as a Cement Replacement in High Strength Sustainable Concrete

2020 ◽  
Vol 1007 ◽  
pp. 90-98
Author(s):  
Ash Ahmed ◽  
Fraser Hyndman ◽  
John Kamau ◽  
Heni Fitriani
Keyword(s):  
Mechanical Properties ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Construction Material ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Strength Development ◽  
Coal Waste ◽  
Environmental Implications ◽  
Sustainable Concrete

Cement is the most utilized construction material. The energy-intensive processes that are involved in its production contribute up to 10% of total global CO2 emissions, with potentially adverse environmental implications. It is however possible, that energy and cost efficiency can be achieved by reducing on the amount of clinker, and in its place utilising supplementary cementitious materials (SCMs) or pozzolans that require less process heating and emit fewer levels of CO2. Currently, most sustainable concrete uses either GGBS (slag) or PFA (fly ash) to reduce the quantity of cement used in construction and highways applications. GGBS and PFA come from industries (steel and coal waste respectively) which are in decline that should not be relied upon in the long term. This report shows that cement in concrete can also be replaced with rice husk ash (RHA) which actually enhances the mechanical properties. RHA comes from the food production industry and is vital for the growing global population. It is thus a socially responsible objective to use a pozzolan in civil engineering applications that is sourced from an environmentally friendly and sustainable industry. This study investigated the potential of RHA to be used as a SCM by evaluating mechanical properties. Experiments were carried out by supplementing cement in concrete mixes with RHA at up to 10% replacement by mass. Results were compared with a control specimen (100% cement), with a water/binder (w/b) ratio of 0.4 and C32/40 design mix using CEM I. The results show excellent early age strengths with all RHA mixes surpassing 40 MPa strength within 7 days which is contrary to general trends in SCM concrete where strength development is slow in the initial stages in comparsion to 100% cement concrete. All RHA specimens exhibited impressive flexural and tensile strengths.

scholarly journals Use of Rice Husk Ash (RHA) as a Supplementary Cementitious Material in Producing Normal Concrete

2019 ◽  
Vol 271 ◽  
pp. 07007
Author(s):  
Kazi islam ◽  
Zahid Hossain
Keyword(s):  
Rice Husk ◽  
Rice Husk Ash ◽  
Construction Material ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Hardened Concrete ◽  
Type I ◽  
Continuous Increase ◽  
Material Sources ◽  
By Products

With the continuous increase of scarcity of the natural construction material sources and environmental awareness, utilization of wastes/by-products in the construction industry has become an attractive field of study. Several industrial by-products produced from different manufacturing processes have been considered for various usages in the construction field. This paper briefly describes the potential use of Rice Husk Ash (RHA) as Supplementary Cementitious Materials (SCM). Here, three different grades of RHA (600-RHA, 150-RHA, and 44-RHA) in two different percentages (10 % and 20 %) of replacement of Type I Ordinary Portland Cement (OPC) were investigated. Laboratory tests on the fresh concrete mix as well as the mechanical properties of the hardened concrete were performed. It was observed that coarser RHA-modified concrete (600-RHA and 150-RHA) showed reduced strength properties while finer RHA (44-RHA) exhibited improved concrete properties. Moreover, the incorporation of RHA in concrete was found to be effective in mitigating alkaline expansion.

Characterization of Cement-Rice Husk Ash Composites

2017 ◽  
Vol 866 ◽  
pp. 187-190
Author(s):  
Thossapon Jaihlong ◽  
Nittaya Jaitanong ◽  
Suparut Narksitipan
Keyword(s):  
Portland Cement ◽  
Rice Husk ◽  
Fiber Optic ◽  
Rice Husk Ash ◽  
Cementitious Materials ◽  
Cement Composites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lime Water

In present research, the cement-rice husk ash composites were prepared and characterized. The samples were added fiber optic and rice husk ash was used as replacement cementitious materials at 10, 20, 30 and 40 wt% of portland cement. The samples were demolded after 24 h casting and cured in saturated lime water for 3 days. After these periods, the samples were wrapped with plastics films for 7 and 28 days. Then, samples were dried in air for 24 h. The chemical compositin of portland cement and rice husk ash were characterized by using x-ray fluorence spectrometry (XRF). Additionally, dried samples were analysized phase compositions and crystalline structure by using x-ray diffraction (XRD) technique. The chemical element compositions and microstructure were detected by scanning electron microscopy (SEM), respectively. Moreover, The effect of rice husk ash in these cement composites were investigated in this research.

scholarly journals A Study on the Strength Aspects of Concrete with Metakaolin, GGBFS and Rice Husk Ash as Partial Replacement of OPC

2021 ◽  
Vol 889 (1) ◽  
pp. 012072
Author(s):  
Amit Sharma ◽  
Sanjeev Gupta
Keyword(s):  
Rice Husk ◽  
Rice Husk Ash ◽  
Research Work ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Engineering Properties ◽  
Partial Replacement ◽  
Test Results ◽  
Conventional Concrete ◽  
The Impact

Abstract The impact of the OPC on the environment is important as its production generates a large amount of CO2. In order to reduce the use of pure raw materials as resources, the use of industrial waste or secondary materials in construction sites for the production of cement and concrete has been encouraged. The volume of wastes generated worldwide has increased over the years due to the population, social and economic performance and social development. One of the most attractive options for waste management is to minimize waste and reuse the possibility of recycling. The cost of cement used in concrete works is increasing and unsatisfactory, but the demand for this material and other housing needs is rising, so it is important to find alternatives that can be used alone or in a partial replacement. In this research work several auxiliary cementitious ingredients such as metakaoline, GGBFS and Rice Husk Ash (RHA) were used to improve the strength properties of the conservative concrete. Metakaolin and GGBFS was used at a fixed percentage of 10 percent as fractional substitution of the OPC-43 grade cement, while the RHA was used at different percent ranging from 0 to 25 percent at an increment of 5 percent in each case as fractional substitution of the OPC-43 grade cement. Numerous examinations were executed so as to envisage the effect of these materials over the strength and engineering properties of the concrete. The test results conclude that the usage of the metakaolin, GGBFS and the RHA in combined form increased the strength and engineering properties of the conventional concrete up to a great extent. From the obtained test results it can be further concluded that the particle size of the supplementary cementitious materials plays a significant role in enhancing the internal micro-structure of the concrete and which further leads to the higher strength of the concrete. Also the main reason behind the advanced strength was the presence of the metakaolin and GGBFS in the concrete, whose chemical properties densifies the concrete and made the concrete more stable and promotes higher strength. Future work can also be done on the usage of several other supplementary cementitious materials at different other percentages so as to improve concrete properties.

scholarly journals Performance of Rice Husk Ash as Supplementary Cementitious Material after Production in the Field and in the Lab

Materials ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4319
Author(s):  
Mareike Thiedeitz ◽  
Wolfram Schmidt ◽  
Michelle Härder ◽  
Thomas Kränkel
Keyword(s):  
Rice Husk ◽  
High Performance ◽  
High Performance Concrete ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Cement Clinker ◽  
Cement Pastes ◽  
Laboratory Conditions ◽  
Controlled Conditions ◽  
Concrete Production

Supplementary cementitious materials (SCM) can reduce the total amount of Portland cement clinker in concrete production. Rice husk ashes (RHA) can be converted from an agricultural by-product to a high-performance concrete constituent due to a high amount of reactive silica with pozzolanic properties if they are burnt under controlled conditions. The way and duration of combustion, the cooling process as well as the temperature have an effect on the silica form and thus, the chemical and physical performance of the RHA. Various studies on the best combustion technique have been published to investigate the ideal combustion techniques. Yet, the process mostly took place under laboratory conditions. Investigating the difference between the performance of RHA produced in a rural environment and laboratory conditions is useful for the assessment and future enhancement of RHA production, and its application both as building material, for example in rural areas where it is sourced in large quantities, and as additive for high performance concrete. Thus, the paper presents a comparison between RHA produced under rudimentary conditions in a self-made furnace in the rural Bagamoyo, Tanzania and under controlled laboratory conditions at the Technical University of Munich, Germany, with different combustion methods and temperatures. In a second step, RHA was ground to reach particle size distributions comparable to cement. In a third step, cement pastes were prepared with 10%, 20% and 40% of cement replacement, and compared to the performance of plain and fly ash blended cement pastes. The results show that controlled burning conditions around 650 °C lead to high reactivity of silica and, therefore, to good performance as SCM. However, also the RHA burnt under less controlled conditions in the field provided reasonably good properties, if the process took place with proper burning parameters and adequate grinding. The knowledge can be implemented in the field to improve the final RHA performance as SCM in concrete.

scholarly journals Investigation of Durability Pozzolanic Efficiency Factor by Means of Surface Resistivity Measurement

2018 ◽  
Author(s):  
Ali A. Ramezanianpour ◽  
Payam Vosoughi ◽  
Faramarz Moodi
Keyword(s):  
Rice Husk ◽  
Natural Zeolite ◽  
Rice Husk Ash ◽  
Resistivity Measurement ◽  
Cementitious Materials ◽  
Efficiency Factor ◽  
Supplementary Cementitious Materials ◽  
Concrete Compressive Strength ◽  
Natural Pozzolans ◽  
Durability Of Concrete

Supplementary cementitious materials (SCMs) are used in concrete due to their properties such as reduction of cement consumption, reducing cost, enhancing concrete compressive strength, and boost durability of concrete against aggressive environment. In this paper, durability pozzolanic efficiency factor of four types of raw natural pozzolans (natural Zeolite, Trass, Tuff, and Pumice) and a type of artificial pozzolans (Rice Husk Ash) with respect to durability of concrete against corrosion of the reinforcement are determined and compared with each other. For this purpose, surface electrical resistivity of 17 kinds of diverse concrete mixture design are measured at two ages (28 and 90 days) using the Wenner four probes apparatus. The results show that natural Zeolite has the highest durability pozzolanic efficiency factor; Trass and Rice Husk Ash are in the second rate, also Tuff and Pumice are in the last place.

scholarly journals Rice Husk Resource for Energy and Cementitious Products with Low CO2 Contributions

2018 ◽  
Vol 59 (1) ◽  
pp. 45-58
Author(s):  
Otto During ◽  
Silu Bhochhibhoya ◽  
Ramesh Kumar Maskey ◽  
Rajendra Joshi
Keyword(s):  
Rice Husk ◽  
Decision Process ◽  
Rice Husk Ash ◽  
Production Systems ◽  
Cementitious Materials ◽  
Climate Impact ◽  
Supplementary Cementitious Materials ◽  
Cement Kiln ◽  
Study Analysis ◽  
Low Co2

Abstract Rice Husk Ash (RHA) is a well-known supplementary cementitious materials (SCMs) that can be used for concrete with reduced CO2 contributions. In 2016, only Nepal produced 5.2 million tonnes rice that gave about 1.14 million tonnes rice husk. The rice husk can also be used directly in a cement kiln as a fuel. This study analysis the potential CO2 reductions from three scenarios and emphasis strengths, weaknesses, opportunities and treats in the production systems for initiate a decision process with possibilities to get an industry project financed from the green climate found. The highest CO2 benefits were from rice husk used in a cement kiln were half of the yearly rice husk production in Nepal could reduce the climate impact with 808000 tonnes CO2.

scholarly journals Geotechnical and microstructural properties of cement-treated laterites stabilized with rice husk ash and bamboo leaf ash

2021 ◽  
Vol 61 (6) ◽  
pp. 722-732
Author(s):  
Emeka Segun Nnochiri ◽  
Olumide Moses Ogundipe ◽  
Samuel Akinlabi Ola
Keyword(s):  
Soil Sample ◽  
Rice Husk ◽  
Cement Hydration ◽  
Rice Husk Ash ◽  
Microstructural Properties ◽  
Index Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bamboo Leaf Ash ◽  
New Compounds

This study investigated the geotechnical and microstructural properties of cement-treated laterites stabilized with rice husk ash and bamboo leaf ash. In going about the tests, the soil sample was subjected to compaction, California Bearing Ratio (CBR) and preliminary tests; such as specific gravity, particle size distribution and Atterbergs limits to determine its index properties. Thereafter, the soil sample was mixed with cement at varying proportions of 0–12% at 2% intervals and also, separately mixed with bamboo leaf ash (BLA) and rice husk ash (RHA) in proportions of 0–16% at 2% intervals. The mixes at each stage were subjected to compaction, Atterberg limits and CBR tests. The highest values were 66.7% and 54.8% for unsoaked and soaked CBR at 6% cement+8% BLA and 78.5% and 63.8% for unsoaked and soaked CBR at 8% cement+8% RHA. Samples at these optimal CBR values were subjected into Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) tests. Results showed that new compounds were formed and there were changes in the microstructural arrangements. It can therefore be concluded that pozzolanic and cement hydration reactions actually took place in the course of stabilization.

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