Research Article 6 Determination of the Effects of Bagasse Ash on the Properties of Portland Cement

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1 Journal of Applied and Industrial Sciences, 2015, 3 (1): 6-11, ISSN: (PRINT), ISSN: (ONLINE) Research Article 6 Determination of the Effects of Bagasse Ash on the Properties of Portland Cement Mashair Khalil Idris 1, Kamal Eldin Eltayeb Yassin 2 1 Sudanese Standard and Metrology Organization Khartoum, Sudan Corresponding author eng_mesha123@hotmail.com 2 Department of Chemical Engineering, Faculty of Engineering, University of Khartoum Khartoum, Sudan kamaltyb@gmail.com (Received January 02, 2015; Accepted February 28, 2015) Abstract -During processing of sugar cane factories in Sudan, the waste of bagasse ash which is normally disposed in landfills is increasing. These wastes in landfills have an adverse effect on the environment, creating air pollution due to smell and dust. Using bagasse ash as a pozzolanic material to replace clinker can reduce the consumption of cement and reduce landfill area requirements and CO2 emissions. It is well known that CO2 is a major contributor to the greenhouse effect and the global warming of the earth. This study tests the use of bagasse ash (BA) as a pozzolanic material for producing high-strength mortar according to the requirements of BS EN 196-1: The study investigated the physical properties and chemical composition of BA as well as compressive strength properties of the mortar produced by percentage (5, 10, 15, 20 and 30)% by weight of replacement Portland clinker with bagasse ash. The mortar cubes were tested at the ages of 2, 7 and 28 days. The results showed that BA is a good pozzolana with combined SiO2, Al2O3 and Fe2O3 of 78.12%. The compressive strength increased with decreasing Portland clinker replacing 5% and 10%. An optimum value of 45.5N/mm2 at 28days was obtained for mortar with 10% BA replacement. It was concluded that 10% BA substitution is adequate to enjoy maximum benefit of strength observed. Index Terms: Sugar cane Bagasse Ash, Pozzolana, Portland Clinker type 1, Mortar I. INTRODUCTION Ordinary Portland cement is recognized as a major construction material throughout the world [1]. Researchers all over the world today are focusing on ways of utilizing either industrial or agricultural waste, as a source of raw materials for industry, this waste utilization would not only be economical, but may also result in foreign exchange earnings and environmental pollution control [2]. Industrial wastes, such as blast furnace slag, fly ash and silica fume are being used as supplementary cement replacement materials [3]. Recently sugarcane (Saccharum officinarum L) [4] bagasse ash, which is a byproduct of sugar factories found after burning sugarcane bagasse which in turn is found after the extraction of all economical sugar from sugarcane, has been tested in some parts of the world for its pozzolanic property and has been found to improve some of the properties of the mortar and concrete like compressive strength [5]. In the Sugar cane industry bagasse (the fibrous residue after crushing and juice extraction of sugar cane) is a major industrial waste product from the milling process in Sudan. Nowadays, it is becoming common to reutilize sugar cane bagasse as a biomass fuel in boilers for vapor and power generation in sugar factories [6]. Burning of bagasse in the boiler produces bagasse ash as a combustion product. Depending on their collection source, bagasse ash is classified as either fly ash or bottom ash. Bagasse fly ash (BFA) is a waste that is collected from the particulates in the upstream of boilers, while waste collected from boiler burners is called bagasse bottom ash (BBA). Bagasse ash is used mainly for land-fill and as filler for building materials.reportedly, BFA can be utilized as low-cost adsorbent for the removal of phenolic compounds,pyridine, dyes, and heavy-metal ions [7]. Depending on the incinerating conditions, the resulting sugar cane bagasse ash (SCBA) may contain high levels of SiO2 and Al2O3, enabling its use as a supplementary cementitious material (SCM) in blended cement systems. In Sudan there are six operational sugar factories that were located in New Halfa in Kassala State, Geneid in Gezira State, Sinner in Sinnar State and Kenana, White Nile and Assalaya in White Nile State. Some of these factories are generating electric power by using the sugarcane bagasse fibers,the result of bagasse ash has been disposed of in landfills and it is now becoming a significant environmental burden [8].The use of SCBA as an SCM to partially replace ordinary Portland cement not only helps reduce methane emissions from disposal of the organic wastes and reduce the production of cement, which is infamous for its high energy consumption and CO2 emission, but also can improve the compressive strength of cement-based materials. Despite this, relatively few researches has been undertaken to examine the potential

2 of this material for incorporation into paste, mortar and concrete [9]. The main objective of this study is, therefore, to study the suitability of bagasse ash produced from Assalaya Sugar Factory in the White Nile State, as a pozzolanic material to partially replace cement(portland clinker) in mortar.towards this, experimental investigations were carried out to examine the impact of adding bagasse ash in Portland cement by partial replacement of Portland clinker at the ratio of 0%, 5%, 10%, 15%,20% and 30% by weights on the properties of pastes and mortar containing bagasse ash, such as normal compressive strength tests, soundness tests, setting time tests and chemical composition tests. The main ingredients consist of Portland clinker, sugar cane bagasse ash (SCBA), local sand and water. After mixing, mortar specimens were casted and subsequently all test specimens were cured in water at 2, 7and 28 Days. The results will be useful for designers and civil engineers to use bagasse ash as a pozzolanic material in concrete. II. MATERIALS AND METHODS Materials One sample of bagasse ash from Assalaya Sugar factory was chosen from five types of BA with respect to their chemical compositions. A fresh clinker from White Nile Cement factory was used. The chemical compositions and physical properties of clinker and bagasse ash were provided in Table (1) &Table (2). 7 Table (1). Physical Properties of Clinker and Bagasse Ash Physical Tests Clinker Bagasse Ash Initial setting time/ minutes Final setting time/ minutes Consistency % Soundness /mm zero No result Table (2). Chemical Composition of Clinker and Bagasse Ash Component Clinker Bagasse Ash SiO Al 2 O Fe 2 O CaO MgO SO L.O.I Preparation of Materials There are no specifications or test methods to determine the grind ability of raw materials. Many types of grinding machines were developed to grind the clinker such as; ball mill, tube mill, rod mill. In this study, the ball type grinder was used. Bagasse ash was taken from Assalaya Sugar Factory, clinker and gypsum were mixed with BA In the different amounts; 5%, 10%,15%,20% and 30% by weights replacement then grinding and screened through a sieve of 212µ mesh size. The gypsum was used at %4 by weight in the production of all cements. Finally, these tests were used to investigate the pozzolanic properties of bagasse ash, its effects on the performance of the mortar such as strength and chemical. Test Methods The composition of the mortar specimen mixes was 1:2:6 (water/cement/local sand). After mixing, the mixtures were cast into 40*40*160 mm steel mold prism and were put into the chamber which was set at 100% humidity and 20±2 C temperature. Steel molds were removed after 24 h and specimens were cured in the water with 20±2 C temperature. Flexural and compressive strength tests were applied at the test ages of 2, 7, and 28 days. First, the flexural test with one-point loading was applied to the center of the specimen (The tests were carried out in accordance with the requirements of BS EN 196-1: Part 1: Determination of strength [10], BS EN 196-2: 2013 method of testing cement Part 2: chemical analysis of cement and EN 196-3: [11]2005 +A method of testing cement Part 3: determination of setting times and soundness) [12]. The broken parts were used for compressive strength test. The experimental results of two identical specimens were averaged for each age.

3 III. RESULTS AND DISCUSSION Table (3) and Table (4) shows content of different percentage clinker to complete the tests and the compressive strength values of mortar. The 8 replacement amount has an important role for the strength development of blending cement at specified ages. Table (3). Bagasse Ash Mixed with Different Percentage Clinker Sample No Gypsum % Bagasse ash % Clinker % 1 4% Zero% 96% 2 4% 5% 91% 3 4% 10% 86% 4 4% 15% 81% 5 4% 20% 76% 6 4% 30% 66% Table (4). Physical and Chemical Analysis for Partial Replacement of Portland Clinker at the Ratio of 0%, 5%, 10%, 15%, 20% and 30% by Weight of Bagasse Ash Sample No 1(zero%) 2(5%) 3 (10%) 4(15%) 5(20%) 6(30%) Physical Analysis Compressive 2Days Strength N/mm 2 7Days Days Initial Final Setting time / minutes Consistency % Soundness/mm Chemical Analysis SiO Al 2 O Fe 2 O CaO MgO SO L.O.I

4 Compressive Strength (N/mm2) Journal of Applied and Industrial Sciences, 2015, 3(1): 6-11, ISSN: (PRINT), ISSN: (ONLINE) 9 Therefore, the relationship between bagasse ash content and strength development were taken into consideration and represented in Figure (1) % 5% 10% 15% 20% 30% 0 2Days 7Days 28 Days Bagasse Ash % Figure (1). Relationship between Portland Clinker Replacing with Percentage of Bagasse Ash in Compressive Strength of Mortar However, illustrates the typical development of compressive strength for clinker and bagasse ash adding 0%, 5%, 10%, 15%, 20% and 30% for 2 days, 7days and 28 days. It is evident that, the compressive strength of Mortar increases with 5%bagasse ash to 10% then decreases up to 30% by adding bagasse ash at different ages for blending cement. One-way analysis of variance (ANOVA) test was made for the physical, chemical and mechanical data obtained from the three experiments. The results indicate that a very highly significant differences (0.000) at the 0.05 confidence levels. A post-hock least significant difference (LSD) were applied for all parameters and levels and found significant too, except for two levels of the physical analysis and one level of the chemical analysis. The physical analysis levels were 5 % and 10 % bagasse ash replacement percentages for two and 28 days, respectively (Table 5). However, for the chemical analysis, only 15 % bagasse ash percentage replacement with ferric oxide was not significant (Table 6). Table (5) Mean Comparison used Least Significant Difference (LSD) test for the Compressive Strength at two and 28days (CS2, CS28) of Bagasse Ash Treat Mean Difference Standard Error significant CS2 5% CS28 10% The mean difference is significant at the 0.05 level.

5 Table (6) Mean Comparison used Least Significant Difference (LSD) test for the Chemical test for ferric oxide at 15 % replacement of Bagasse Ash Treat Mean Difference Standard Error significant FE2O3 15% BA The mean difference is significant at the 0.05 level. 10 Those results on Tables (5) and (6) indicate that the bagasse ash replacement did not affect the physical and chemical analysis for the specific combinations. These conclude that for Portland cement, the research agreed on the fact that up to 5 % bagasse ash replacement meets the international standards. Nevertheless, for Portland cement, all the bagasse ash replacement percentages meet the international standards for compressive strength for two days, up to 15 % and 10 % for 28 days. However, for Portland pozzolana and pozzolana cements, all the replacements and additives meets the international standards up to the 30 % for all intervals. Thus, additional bagasse ash replacements could be studied to decrease the cost effectiveness of Portland clinker as presented in Table (7). Table (7) Mechanical parameters for 2, 7 and 28 days for the different bagas ash replacement percentages and the portland, portland pozzolana and pozzolana international and Sudanese standards. Bagasse Ash Additives 2 days Tested 7 days Tested samples 28 days Tested samples samples means means/ N/mm 2 means/ N/mm 2 0% 21.9 N/mm % % % % Not less than 30N/mm 2 Not less than 42.5 N/mm 2 30% Portland cement Not less than (5 % additives) 10N/mm 2 Portland Pozzolana cement NA Not less than 16N/mm 2 Not less than 32.5 N/mm 2 (36 55 % additives) Pozzolana cement NA Not less than 16N/mm 2 Not less than 32.5 N/mm 2 (45 64 additives) NA: Data not available IV. CONCLUSIONS AND RECOMMENDATIONS In accordance with the presented results, it is possible to conclude that: - Compressive strength has been successfully increased by adding bagasse ash. Results confirm that higher strength can be obtained by replacing 5 % of Portland clinker by Bagasse Ash this could minimize the environmental impact of Bagasse Ash waste disposal. - The study recommends the use of Bagasse Ash as natural Pozzolana up to 30 %. - More research needed to define the applicable limits of replacing bagasse ash of Portland clinker for producing pozzolana cement. REFERENCES [1] İ. ALP et al, Pozzolanic Characteristics of a Natural Raw Material for use in blended cements, Iranian Journal of Science & Technology, Transaction B, Engineering, Vol. 33, No. B4, pp Printed in The Islamic Republic of Iran, 2009 Shiraz University [2] Aigbodion.V.S et al,the use of rice husk ash as an aggregate for foundry sand production in Nigeria, Proceedings of The Nigerian Metallurgical Society (NMS),

6 (2008) Annual Conference & Annual GeneralMeeting, pp [3] R.Srinivasan and K.Sathiya, Experimental Study on Bagasse Ash in Concrete, International Journal for Service Learning in Engineering, Vol. 5, No. 2, pp , Fall 2010 ISSN [4] Samir K. Abdullah and Yehya A. Saleh, Mycobiota Associated with Sugarcane (Saccharum officinarum L.) Cultivars in Iraq, Jordan Journal of Biological Sciences Volume 3, Number 4, December 2010 ISSN Pages [5] Biruk Hailu, Bagasse ash as a cement replacing material, Master of Science in Civil Engineering Addis Ababa, December 2011 [6] Sirirat Janjaturaphan and Supaporn Wansom, Phnology Center (MTEC), National Science and Technology Development Agency (NSTDA), 114 Thailand Science Park, Paholyothin Rd., Klong 1, Klongluang, Pathumthani (4): [7] Samsudin Affandi et al, A facile method for production of high-purity silica xerogels from bagasse ash, Advanced Powder Technology 20 (2009) [8] Mohamed Eljack Suliman and Samah M. Fudl Almola, The Use of Sugarcane BagasseAsh as analternative Local Pozzolanic Material: Study of Chemical Composition, A scientific journal of COMSATS SCIENCE VISION Vol.16 and Vol. 17 (January 2010 to December 2011) [9] Nuntachai Chusilp et al. Development of bagasse ash as a pozzolanic material in concrete, Asian Journal on Energy and Environment. 2009, 10(03), [10] BS EN 196-1: 2005 method of testing cement Part 1: determination of strength [11] BS EN 196-2: 2013 method of testing cement Part 2: chemical analysis of cement [12] EN 196-3: A method of testing cement Part 3: determination of setting times and soundness 11