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Sample records for husk ash addition

  1. influence of addition of rice husk ash on porcelain composition

    African Journals Online (AJOL)

    ABSTRACT. Rice husk ash (RHA) has long been known to possess high silica content. The abundance of rice husk as agricultural waste makes it the most promising to be used as a supplementary cementations and ceramic material. In this study RHA was used as an additive material on porcelain body. The rice husk was ...

  2. Influence of Addition of Rice Husk Ash on Porcelain Composition ...

    African Journals Online (AJOL)

    Rice husk ash (RHA) has long been known to possess high silica content. The abundance of rice husk as agricultural waste makes it the most promising to be used as a supplementary cementations and ceramic material. In this study RHA was used as an additive material on porcelain body. The rice husk was subjected to ...

  3. Use or rice husk ash an addition in mortar

    Directory of Open Access Journals (Sweden)

    Sánchez de Rojas, M. Isabel

    1986-09-01

    Full Text Available With the aid of a 400-litre capacity pilot furnace, in which 40 Kg of rice husk is submitted to controlled combustion, an ash (RHA is obtained for use as an addition, the physicochemical properties of which form the focal point of this work. Results will also be presented for the combustion power of the husk ≃ 4000 kcal/kg, being greater than half the value for normal bituminous coals. Conglomerates have been obtained by mixing RHA with different proportions of lime and portland cement, and their properties are studied with regard to both mortars and concretes. The ultimate aim of the work is to demonstrate how rice husk (world production of which is estimated at 500.106 m3 per annum may be feasibly applied as an addition, without forgetting its excellent properties as a fuel, which makes it particularly suitable for developing countries with a shortage of cement and energy resources.

    Mediante la utilización de un horno-piloto de unos 400 litros de capacidad, en el que se realiza la combustión controlada de unos 40 kg de cáscara de arroz, se consigue una ceniza (RHA, sobre cuyas propiedades físico-químicas se centra el trabajo, para su empleo como adición. Se presentan igualmente resultados sobre el poder de combustión de la cascara ≃ 4.000 kcal/kg, superior a la mitad del valor de los carbones bituminosos normales. Mediante mezclas de RHA con distintas proporciones de cal o de cemento portland, se han conseguido conglomerantes cuyas propiedades se estudian, tanto sobre morteros, como sobre hormigones. El objetivo último del trabajo es mostrar la factible aplicabilidad de la cascara de arroz (cuya "producción" mundial se estima en 500.106 m3 anuales como adición, sin olvidar sus excelentes cualidades como combustible lo que hace especialmente idónea en países en vías de desarrollo, deficitarios en cemento y recursos energéticos.

  4. Fabrication of Silica Glass from Rice Husk Ash with Spodumene Additions

    Science.gov (United States)

    Wasanapiarnpong, T.; Vorajesdarom, B.; Rujirakamort, E.; Nilpairach, S.; Mongkolkachit, C.

    2011-10-01

    Silica glass is an interesting material due to its low thermal expansion coefficient, high chemical inertness, and transparency. In this study, low cost rice husk ash waste containing mainly amorphous silica phase was used as a starting raw material. Formation of cristrobalite caused product damage during cooling down was suppressed by an addition of some sintering aids. Spodumene was selected to use as the sintering aid due to its ability to promote the sinterability of the rice husk ash by liquid phase forming. Lithium carbonate and aluminum nitrate were mixed with the rice husk ash as starting chemicals for spodumene forming. To investigate the effects of spodumene addition on densification, physical properties and thermal expansion coefficient, 25 and 50 mass% of spdumene were added to the mixture. Mixed powders were dry pressed into pellet shapes and sintered at 1000-1250 °C for 30 min in an electric furnace. It was found that 50 mass% addition of spodumene enhanced the densification of the specimens sintered at the temperature higher than 1250 °C. Water absorption was reduced to 1.11 % with bulk density of 2.12 g/cm3. Low thermal expansion coefficient of 2.70×10-6 /°C was achieved with only the petalite phase detection.

  5. Fabrication of Silica Glass from Rice Husk Ash with Spodumene Additions

    Energy Technology Data Exchange (ETDEWEB)

    Wasanapiarnpong, T; Vorajesdarom, B; Rujirakamort, E [Research Unit of Advanced Ceramics, Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); Nilpairach, S [Metallurgy and Materials Science Research Institute, Chulalongkorn University, Bangkok (Thailand); Mongkolkachit, C, E-mail: thanakorn.w@chula.ac.t [National Metal and Materials Technology Center, Pathumthani (Thailand)

    2011-10-29

    Silica glass is an interesting material due to its low thermal expansion coefficient, high chemical inertness, and transparency. In this study, low cost rice husk ash waste containing mainly amorphous silica phase was used as a starting raw material. Formation of cristrobalite caused product damage during cooling down was suppressed by an addition of some sintering aids. Spodumene was selected to use as the sintering aid due to its ability to promote the sinterability of the rice husk ash by liquid phase forming. Lithium carbonate and aluminum nitrate were mixed with the rice husk ash as starting chemicals for spodumene forming. To investigate the effects of spodumene addition on densification, physical properties and thermal expansion coefficient, 25 and 50 mass% of spdumene were added to the mixture. Mixed powders were dry pressed into pellet shapes and sintered at 1000-1250 deg. C for 30 min in an electric furnace. It was found that 50 mass% addition of spodumene enhanced the densification of the specimens sintered at the temperature higher than 1250 deg. C. Water absorption was reduced to 1.11 % with bulk density of 2.12 g/cm{sup 3}. Low thermal expansion coefficient of 2.70x10{sup -6} /deg. C was achieved with only the petalite phase detection.

  6. Rice husk (RH) as additive in fly ash based geopolymer mortar

    Science.gov (United States)

    Yahya, Zarina; Razak, Rafiza Abd; Abdullah, Mohd Mustafa Al Bakri; Rahim, Mohd Azrin Adzhar; Nasri, Armia

    2017-09-01

    In recent year, the Ordinary Portland Cement (OPC) concrete is vastly used as main binder in construction industry which lead to depletion of natural resources in order to manufacture large amount of OPC. Nevertheless, with the introduction of geopolymer as an alternative binder which is more environmental friendly due to less emission of carbon dioxide (CO2) and utilized waste materials can overcome the problems. Rice husk (RH) is an agricultural residue which can be found easily in large quantity due to production of paddy in Malaysia and it's usually disposed in landfill. This paper investigated the effect of rice husk (RH) content on the strength development of fly ash based geopolymer mortar. The fly ash is replaced with RH by 0%, 5%, 10%, 15% and 20% where the sodium silicate and sodium hydroxide was used as alkaline activator. A total of 45 cubes were casted and their compressive strength, density and water absorption were evaluated at 1, 3, and 7 days. The result showed compressive strength decreased when the percentage of RH increased. At 5% replacement of RH, the maximum strength of 17.1MPa was recorded at day 7. The geopolymer has lowest rate of water absorption (1.69%) at 20% replacement of RH. The density of the sample can be classified as lightweight geopolymer concrete.

  7. The Effect of Commercial Rice Husk Ash Additives on the Porosity, Mechanical Properties, and Microstructure of Alumina Ceramics

    Directory of Open Access Journals (Sweden)

    Mohammed Sabah Ali

    2017-01-01

    Full Text Available A porous ceramic is made from composite materials which consist of alumina and commercial rice husk ash. This type of ceramics is obtained by mixing the commercial rice husk ash as a source of silica (SiO2 and a pore forming agent with alumina (Al2O3 powder. To obtain this type of ceramic, a solid-state technique is used with sintering at high temperature. This study also investigated the effects of the rice husk ash ratios on the mechanical properties, porosity, and microstructure. The results showed that, by increasing the content of the rice husk ash from 10 to 50 wt%, there is an increase in the porosity from 42.92% to 49.04%, while the mechanical properties decreased initially followed by an increase at 30 wt% and 50 wt%; the hardness at 20 wt% of the ash content was recorded at 101.90 HV1. When the ash content was increased to 30 wt% and 50 wt%, the hardness was raised to 150.92 HV1 and 158.93 HV1, respectively. The findings also revealed that the tensile and compressive strengths experienced a decrease at 10 wt% of the ash content and after that increase at 30 wt% and 50 wt% of rice husk ash. XRD analysis found multiple phases of ceramic formation after sintering for the different rice husk ash content.

  8. THE COMPRESSIVE AND FLEXURAL STRENGTHS OF SELF-COMPACTING CONCRETE USING RAW RICE HUSK ASH

    Directory of Open Access Journals (Sweden)

    MD NOR ATAN

    2011-12-01

    Full Text Available This study investigates the compressive and flexural strengths of self-compacting concrete incorporating raw rice husk ash, individually and in combination with other types of mineral additives, as partial cement replacement. The additives paired with raw rice husk ash were fine limestone powder, pulverized fuel ash and silica fumes. The mix design was based on the rational method where solid constituents were fixed while water and superplasticizer contents were adjusted to produce optimum viscosity and flowability. All mixes were designed to achieve SF1 class slump-flow with conformity criteria ≥ 520 mm and ≤ 700 mm. Test results show that 15% replacement of cement using raw rice husk ash produced grade 40 concrete. It was also revealed that 30% and 45% cement replacements using raw rice husk ash combined with limestone powder and raw rice husk ash combined with limestone powder and silica fume respectively, produced comparable compressive strength to normal concrete and improved flexural strengths.

  9. Mechanical properties of millet husk ash bitumen stabilized soil block

    African Journals Online (AJOL)

    This study presents an investigation into the improvement of strength and durability properties of lateritic soil blocks using Millet Husk Ash (MHA) and Bitumen as additives so as to reduce its high cost and find alternative disposal method for agricultural waste. The lateritic soil samples were selected and treated with 0%, ...

  10. Optimalization of silicon extraction from husk ashes by excessive magnesium addition on increasing rate of temperature reduction

    Science.gov (United States)

    Sintha, I.; Dahrul, M.; Ismawati, S. S.; Kurniati, M.; Irmansyah; Irzaman

    2017-05-01

    The Silicon can be extracted from rice husk ash by reducing silica with magnesium. In this study the use of Magnesium and Silica was 49:60 with various rate of increase in the reduction temperature (1 °C/minutes, 3 °C/minutes, and 5°C/minutes). It was done in order to obtain silicon with a higher purity than previous studies. The results of EDX showed that the purity silicon with the increase rate of 1 °C/minutes and 5 °C/minutes were 1.78% and 29.39%, respectively. Then, silicon was not formed by increasing rate of 3 °C/minutes. Moreover, XRD results of the samples by using the increase rate of 1 °C/minutes and 5 °C/minutes showed that the pattern correspond to Silicon while the sample with increase rate of 3 °C/min corresponds to Silica. The FTIR spectra indicate the presence of stretching vibration an harmonic for functional groups of Si-O-Si with spring constant for the increase rate of 1 °C/minutes, 3 °C/minutes, and 5 °C/minutes respectively were 977.23 N/m, 1003 N/m, and 982.3 N/m. FTIR result was consistent with EDX and XRD result proving by the existence of Si-O-Si functional group which showed the purity silicon produced was not optimum and presence of OH-functional group indicate that sample contained water

  11. Pozzolanicity and Some Engineering Properties of Rice Husk Ash ...

    African Journals Online (AJOL)

    Rice Husk Ash (RHA) is an agro-waste material. It is found locally in abundance in Nigeria and many other parts of the world. Rice Husks pose environmental nuisance in developing countries. Efforts have been made to convert the material to economic usage. RHA is a form of pozzolan, a potential cementitious material.

  12. Effect of Neem Seed Husk Ash on Concrete Strength Properties ...

    African Journals Online (AJOL)

    Neem Seed Husk is a by-product obtained during industrial processing of Neem Seed to extract oil and produce fertilizer. Laboratory tests on Neem seed husk ash (NSHA) mixed with cement were conducted to find its effect on concrete strength and workability. Tests including slump test, compressive strength test, concrete ...

  13. Influence of Rice Husk Ash on Mechanical Properties and Stress ...

    African Journals Online (AJOL)

    An attempt has been made in the investigation reported in this paper to study the influence of rice husk ash on the fresh, hardened properties and stress-strain behaviour of standard grade (M 30) SCC. Three SCC mixes with optimized quantities of mineral admixtures like fly ash(FA), ground granulated blast furnace slag ...

  14. Mechanical performance of porous concrete pavement containing nano black rice husk ash

    Science.gov (United States)

    Ibrahim, M. Y. Mohd; Ramadhansyah, P. J.; Rosli, H. Mohd; Ibrahim, M. H. Wan

    2018-01-01

    This paper presents an experimental research on the performance of nano black rice husk ash on the porous concrete pavement properties. The performance of the porous concrete pavement mixtures was investigated based on their compressive strength, flexural strength, and splitting tensile strength. The results indicated that using nano material from black rice husk ash improved the mechanical properties of porous concrete pavement. In addition, the result of compressive, flexural, and splitting tensile strength was increased with increasing in curing age. Finally, porous concrete pavement with 10% replacement levels exhibited an excellent performance with good strength compared to others.

  15. Utilisation of rice husk ash for improvement of deficient soils in Nigeria

    African Journals Online (AJOL)

    Review of studies, mostly carried out at laboratory scale, on the utilisation of Rice Husk Ash (RHA) for improvement of deficient soils in Nigeria is presented. Although, few studies have focused on using the RHA as soil improving additive alone, most of the studies have been on its usage as additive to the conventional soil ...

  16. pozzolanicity and some engineering properties of rice husk ash

    African Journals Online (AJOL)

    HON

    (Neville, 1996). Rice Husks have been found to contain very high silica content, slow firing at a room temperature of 500 to 700 degrees Celsius. (Roy, 1987). The resulting ash is amorphous with a porous structure (Massazza, 1979). The ash has a specific surface as high as 50,000m2/kg and a specific gravity of 1.9 to 2.4 ...

  17. Effects of Groundnut Husk Ash-blended Cement on Chemical ...

    African Journals Online (AJOL)

    The study concluded that OPC/GHA concrete having proven resistant to magnesium sulphate and sodium chloride media would perform better in soils containing MgSO4 and NaCl. Key words: Blended cement; groundnut husk ash; magnesium sulphate; sodium chloride; sulphuric acid; compressive strength; durability of ...

  18. RICE-HUSK ASH-CARBIDE-WASTE STABILIZATION OF ...

    African Journals Online (AJOL)

    This paper present results of the laboratory evaluation of the characteristics of carbide waste and rice husk ash stabilized reclaimed asphalt pavement waste with a view to determine its suitability for use as flexible pavement material. The mixtures were subjected to British Standard heavy compactive effort to determine the ...

  19. Compressive Strength Of Rice Husk Ash-Cement Sandcrete Blocks ...

    African Journals Online (AJOL)

    There is growing demand for alternative, low-cost building material in developing countries. The effect of partial substitution of ordinary Portland cement with Rice Husk Ash (RHA) on the compressive strength of hollow sandcrete block was investigated through laboratory experimental procedures. The specific gravity, initial ...

  20. Study on the effects of white rice husk ash and fibrous materials additions on some properties of fiber-cement composites.

    Science.gov (United States)

    Hamzeh, Yahya; Ziabari, Kamran Pourhooshyar; Torkaman, Javad; Ashori, Alireza; Jafari, Mohammad

    2013-03-15

    This work assesses the effects of white rice husk ash (WRHA) as pozzolanic material, virgin kraft pulp (VKP), old corrugated container (OCC) and fibers derived from fiberboard (FFB) as reinforcing agents on some properties of blended cement composites. In the sample preparation, composites were manufactured using fiber-to-cement ratio of 25:75 by weight and 5% CaCl(2) as accelerator. Type II Portland cement was replaced by WRHA at 0%, 25% and 50% by weight of binder. A water-to-binder ratio of 0.55 was used for all blended cement paste mixes. For parametric study, compressive strength, water absorption and density of the composite samples were evaluated. Results showed that WRHA can be applied as a pozzolanic material to cement and also improved resistance to water absorption. However, increasing the replacement level of WRHA tends to reduce the compressive strength due to the low binding ability. The optimum replacement level of WRHA in mortar was 25% by weight of binder; this replacement percentage resulted in better compressive strengths and water absorption. OCC fiber is shown to be superior to VKF and FFB fibers in increasing the compressive strength, due to its superior strength properties. As expected, the increase of the WRHA content induced the reduction of bulk density of the cement composites. Statistical analysis showed that the interaction of above-mentioned variable parameters was significant on the mechanical and physical properties at 1% confidence level. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  1. Rice Husk Ash Derived Zeolite Blended with Water Hyacinth Ash for Enhanced Adsorption of Cadmium Ions

    OpenAIRE

    G. W. Mbugua; H.M. Mbuvi; J. W. Muthengia

    2014-01-01

    In order to helpcurtail or imposesustained control to the offensive water hyacinth plant,it is essential to explore ways of generatingwater remediation materials from it. In the current study, the capacity and efficacy of water hyacinth ash (WHA),its insoluble residue (WHAR) and rice husk ash (RHA)to remove cadmium ionsand methylene blue from contaminated water was investigated. Mixtures of the two ashes were used to formulatezeolitic materialsby hydrothermal reactions. Material A, ZMA was pr...

  2. Magnesiothermic reduction of rice husk ash for electromagnetic wave adsorption

    Science.gov (United States)

    Liu, Shu-Ting; Yan, Kang-kang; Zhang, Yuan hu; Jin, Shi-di; Ye, Ying; Chen, Xue-Gang

    2015-11-01

    The increase in electromagnetic pollution due to the extensive exploitation of electromagnetic (EM) waves in modern technology creates correspondingly urgent need for developing effective EM wave absorbers. In this study, we carried out the magnesiothermic reduced the rice husk ash under different temperatures (400-800 °C) and investigated the electromagnetic wave adsorption of the products. The EM absorbing for all samples are mainly depend on the dielectric loss, which is ascribed to the carbon and silicon carbide content. RA samples (raw rice husk ashed in air and was magesiothermic reduced in different temperatures) exhibit poor dielectric properties, whereas RN samples (raw rice husk ashed in nitrogen and was magesiothermic reduced in different temperatures) with higher content of carbon and silicon carbide display considerable higher dielectric loss values and broader bandwidth for RL<-5 dB and -10 dB. For RN samples, the maximum bandwidth for -5 dB and -10 dB decrease with carbon contents, while the optimum thickness decrease with increasing SiC content. The optimum thickness of RN400-800 for EM absorption is 1.5-2.0 mm, with maximum RL of between -28.9 and -68.4 dB, bandwidth of 6.7-13 GHz for RL<-5 dB and 3.2-6.2 GHz for RL<-10 dB. The magnesiothermic reduction will enhance the potential application of rice husk ash in EM wave absorption and the samples benefited from low bulk density and low thickness. With the advantages of light-weight, high EM wave absorption, low cost, RN400-800 could be promising candidates for light-weight EM wave absorption materials over many conventional EM wave absorbers.

  3. Mechanical Properties of Concrete Using Eggshell Ash and Rice Husk Ash As Partial Replacement Of Cement

    Directory of Open Access Journals (Sweden)

    Afizah Asman Nurul Shahadahtul

    2017-01-01

    Full Text Available This research was carried out to determine the optimum percentage of eggshell ash and rice husk ash (RHA as partial cement replacement. The samples were tested for its mechanical properties by using concrete grade G30 with cube mould (100 mm × 100 mm × 100 mm and prisms (100 mm × 100 mm × 500 mm. The samples were mixed with eggshell ash and RHA admixture with different proportions (2%:8%, 4%:6%, 6%:4%. Several types of test were conducted towards the samples, which are the slump test, compressive and flexural test. Based on previous researches, the strength of concrete reduced as replaced with eggshells. Most of the researches show the similar trend when partial cement is replaced using eggshell ash. Thus, to increase the strength, an admixture which has pozzolanic reactivity called rice husk ash (RHA is introduced into mix design which has been proved can help to improve the strength of concrete.

  4. Rice husk ash with high carbon content proves favourable for soil stabilization

    NARCIS (Netherlands)

    Pham, P.V.; van der Star, WRL; van Paassen, L.A.; Ye, G.

    2015-01-01

    Rice husk ash is a promising pozzolanic material produced from rice husk burning and has significant potential a sustainable replacement for cement in construction and ground improvement applications. In this study the effect of burning conditions on the ash reactivity and its potential for soil

  5. Clay bricks prepared with sugarcane bagasse and rice husk ash – A sustainable solution

    Directory of Open Access Journals (Sweden)

    Azhar Saleem Muhammad

    2017-01-01

    Full Text Available This study aims to characterize the clay bricks produced by the addition of the two agricultural waste materials i.e. sugarcane bagasse and rice husk ash. Disposing off these waste materials is a very challenging task and is a hazard to environment. The sugarcane bagasse and rice husk ash were collected locally from the cities of Peshawar and Wazirabad, respectively. These were mixed with the clay for brick manufacturing in three different proportions i.e. 5, 10 and 15% by weight of clay. Mechanical i.e. compressive strength and modulus of rupture and durability properties i.e. water absorption; freeze-thaw and sulphate resistance of these bricks were evaluated. Test results indicated that the sulphate attack resistance and efflorescence of clay bricks incorporating sugarcane bagasse and rice husk ash have been increased significantly. However, no significant effect on mechanical properties was observed. Furthermore, the additions of wastes have reduced the unit weight of bricks which decrease the overall weight of the structure leading to economical construction. Therefore, it can be concluded that the addition of waste materials in brick manufacturing can minimize the environmental burden leading towards more economical and sustainable construction.

  6. Use of Rice Husk-Bark Ash in Producing Self-Compacting Concrete

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    Sumrerng Rukzon

    2014-01-01

    Full Text Available This paper presents the use of blend of Portland cement with rice husk-bark ash in producing self-compacting concrete (SCC. CT was partially replaced with ground rice husk-bark ash (GRHBA at the dosage levels of 0%–40% by weight of binder. Compressive strength, porosity, chloride penetration, and corrosion of SCC were determined. Test results reveal that the resistance to chloride penetration of concrete improves substantially with partial replacement of CT with a blend of GRHBA and the improvement increases with an increase in the replacement level. The corrosion resistances of SCC were better than the CT concrete. In addition, test results indicated that the reduction in porosity was associated with the increase in compressive strength. The porosity is a significant factor as it affects directly the durability of the SCC. This work is suggested that the GHRBA is effective for producing SCC with 30% of GHRBA replacement level.

  7. Mechanical Properties of Millet Husk Ash Bitumen Stabilized Soil Block

    Directory of Open Access Journals (Sweden)

    M. T. Abdulwahab

    2017-06-01

    Full Text Available This study presents an investigation into the improvement of strength and durability properties of lateritic soil blocks using Millet Husk Ash (MHA and Bitumen as additives so as to reduce its high cost and find alternative disposal method for agricultural waste. The lateritic soil samples were selected and treated with 0%, 10%, 15%, 20%, 30%, 40% and 50% of MHA by weight of laterite. The lateritic soil-MHA mixture was later admixed with 0%, 2%, 4%, 6%, 8%, 10%, 12% and 14% cut-back bitumen solution by weight of laterite. Both the natural lateritic soil, lateritic and MHA, and the blend of Soil, MHA and Bitumen were first subjected to physical and chemical analysis using X-Ray Fluorescence (XRF and Scanning Electromagnetic Machine (SEM to determine their engineering properties followed by the performance test on bricks cast with varying quantities of the additives. A total of one hundred and ninety two (192 cubes were tested for moisture absorption, erodability and compressive strength tests. The result of the test showed that MHA and Bitumen acted as pozzolana in performance test on the soil blocks. Up to 30% MHA – laterite and 20% MHA admixed with 8% laterite were found to give optimum compressive strength of 10.8N/mm2 and 10.9N/mm2 for the bricks produced. The result also showed that about 50% MHA blended with 14% Bitumen solution ensured water tight bricks. Thus the use of MHA as partial replacement of cement will provide an economic use of by-product and consequently produce a cheaper soil block construction without comprising its strength.

  8. Conversion of rice husk ash to zeolite beta.

    Science.gov (United States)

    Prasetyoko, Didik; Ramli, Zainab; Endud, Salasiah; Hamdan, Halimaton; Sulikowski, Bogdan

    2006-01-01

    White rice husk ash (RHA), an agriculture waste containing crystalline tridymite and alpha-cristobalite, was used as a silica source for zeolite Beta synthesis. The crystallization of zeolite Beta from RHA at 150 degrees C in the presence of tetraethylammonium hydroxide was monitored by XRD, FTIR and (29)Si MAS NMR techniques. It was found that zeolite Beta started to form after 12h and the complete crystallization of zeolite Beta phase was achieved after 2d. XRD, (29)Si MAS NMR and solid yield studies indicate that the transformation mechanism of silica present in RHA to zeolite Beta involves dissolution of the ash, formation of an amorphous aluminosilicate after 6h of crystallization, followed by dissolution in the mother liquor and final transformation to pure zeolite Beta crystals.

  9. the potential use of fonio husk ash as a pozzolana in concrete

    African Journals Online (AJOL)

    eobe

    2016-01-01

    Jan 1, 2016 ... By-products mineral admixtures such as fly ash, rice husk ash and ground granulated blast furnace slag contribute to improvement of concrete performance ... the presence of RHA and cement kiln dust in cement pastes improved the resistance of the mortar to sulfuric acid attack [11]. Palm Kernel Shell Ash ...

  10. COMPARATIVE ASSESSMENT OF RICE HUSK ASH, POWDERED GLASS AND CEMENT AS LATERITIC SOIL STABILIZERS

    Directory of Open Access Journals (Sweden)

    Adebisi Ridwan

    2016-10-01

    Full Text Available This paper compares the stabilizing effects of three different materials, namely: rice husk ash, powdered glass, and cement on the properties of lateritic soil. The basic properties of the lateritic soil were first obtained through colour, moisture content determination, specific gravity, particle size distribution and Atterberg limits tests. Each of the stabilizing materials was then mixed with the lateritic soil in varying percentages of 2.5%, 5%, 7.5%, 10%, 12.5% and 15% by weight of the soil. Thereafter, compaction and California bearing ratio (CBR tests were carried out on the sample mixes to determine the effects of the materials on the lateritic soil. Chemical tests were also carried out on the samples to determine their percentage oxides composition. The compaction test showed that the highest maximum dry densities (MDD obtained for the mixed samples were 2.32 g/cm3 (at 2.5% cement addition, 2.28g/cm3 (at 5% powdered glass (PG addition and 2.18 g/cm3 (at 5% rice husk ash (RHA addition with corresponding optimum moisture contents (OMC of 10.06%, 14.3% and 12.31% respectively. The CBR tests showed that the CBR values increased in all cases as the materials were added with those of the cement and powdered glass giving the highest values and showing close semblance under unsoaked conditions. The chemical test showed that the significant oxides present in the cement, powdered glass and rice husk ash were CaO (53.60%, SiO2 (68.45% and SiO2 (89.84% respectively.

  11. Development of Hybrid Composite Rice Husk Ash (RHA–Geopolymer for Bricks Bearing Buildings

    Directory of Open Access Journals (Sweden)

    Ikhsan Maulana Andi

    2017-01-01

    Full Text Available The aim of this study is to synthesize hybrid composite rice husk ash (RHA-geopolymer as materials for bricks bearing buildings application. Class-C fly ash was used as raw material and rice husk ash (RHA taken directly from the field, washed and dried at 100°C for 4 hours. Geopolymers were synthesized through alkali activation method at 60°C for 1 hour with its molar oxide ration of SiO2/Al2O3 = 3.0, Na2O/SiO2 = 0.2, and H2O/Na2O = 10. There were three series of samples produced by mixing fly ash with addition of 5%, 10% and 15% RHA (relative to the mass of fly ash. The samples were tested after 7 days. The highest compressive strength were 26 MPa which is reached by samples containing 10% RHA. The fire resistance measurement showed that the addition of RHA improved fire retardancy of geopolymers. The samples were immersed in 1 M H2SO4 solution for 4 days for acid resistance examination. The X-Ray Diffraction was performed to examine the chemical compositions of the samples before and after the test took place. Scanning Electron Microscopy (SEM was performed to examine the morphology of these samples surfaces. The addition of 10% RHA in geopolymer showed its excellent properties in terms of mechanical strength, thermal properties, and acid resistance. The study suggests that hybrid composite RHA-geopolymer and can be developed as bricks bearing buildings.

  12. Evaluation of rice husk ash as filler in tread compounds

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, M. R. S., E-mail: monica.fernandes@lanxess.com [Lanxess Elastômeros do Brasil S.A., Brasil and Instituto de Química, Universidade do Estado do Rio de Janeiro (UERJ) (Brazil); Furtado, C. R. G., E-mail: russi@globo.com, E-mail: ana.furtado.sousa@gmail.com; Sousa, A. M. F. de, E-mail: russi@globo.com, E-mail: ana.furtado.sousa@gmail.com [Instituto de Química, Universidade do Estado do Rio de Janeiro (UERJ) (Brazil)

    2014-05-15

    Rice which is one of the largest agriculture crops produces around 22% of rice rusk during its milling process. This material is mainly used as fuel for energy generation, which results in an ash, which disposal represents an environmental issue. The rice husk ash (RHA) contains over than 70% of silica in an amorphous form and a lot of applications is being developed for it all over the world. The use of silica as a filler in the tire industry is growing since it contributes significantly to the reduction of fuel consumption of the automobiles, allowing at the same time better traction (safety). This paper presents an evaluation of the use of RHA as filler in rubber tread compounds prepared in lab scale and compares its performance with compounds prepared with commercial silica and carbon black, the fillers normally used in tire industry. Mechanical and rheological properties are evaluated, with emphasis for tan delta as an indicator of tread performance related with rolling resistance (fuel consumption) and wet grip/traction (safety)

  13. Facile catalytic combustion of rice husk and burning temperature dependence of the ashes.

    Science.gov (United States)

    Xiong, Liangming; Sekiya, Edson H; Wada, Shigetaka; Saito, Kazuya

    2009-11-01

    In this work, it was discovered and demonstrated that the combustion of rice husk is a catalytic process by the thermoanalytical technique. The catalyst involves the oxides of such transition metals as Mn, Fe, and Cu, which are mainly formed in the initial stage of rice husk combustion and remain in the rice husk ash as an impurity. Mn(2+) ions of various concentrations were reloaded into the HCl-washed husk for cocombustion. As a result, the complete combustion temperature of the husk was decreased exponentially depending on the Mn(2+) concentration. By the facile Mn loading technique using a 0.5 M solution, the combustion temperature can be decreased by approximately 100 degrees C, and the resulting ashes themselves can be a good catalyst in the complete combustion of many other organic compounds. The physicochemical properties and amorphous structure of the ashes from both the raw and HCl-washed husks were found to be strongly dependent on the burning temperature. A decreased complete rice husk combustion temperature can be beneficial in preparing porous amorphous silica with high surface area, high densification, and small Si-O-Si band angles.

  14. Synthesis of magnesium silicate from wheat husk ash: Effects of parameters on structural and surface properties

    OpenAIRE

    Pinar Terzioglu; Sevil Yucel

    2012-01-01

    In the present study, magnesium silicate was produced by using wheat husk ash. Wheat husk was burned at 600 °C to obtain an amorphous ash structure, and the ash was processed with sodium hydroxide solution with heat to extract silica. Sodium silicate solution and magnesium salts were used to synthesize magnesium silicate. The present study investigates effects of the feeding rate on magnesium silicate production (0.6 mL/min, 35 mL/min, 70 mL/min), the type of magnesium salt (MgSO4 • 7H2O or M...

  15. Hydrothermal Synthesis of High Crystalline Silicalite from Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    Chaiwat Kongmanklang

    2015-01-01

    Full Text Available The objective of this research work was to evaluate the hydrothermal synthesis of silicalite with high crystallinity within a small particle size. The current study focused on investigating the effects of silica sources such as rice husk ash (RHA and silica gel (SG, crystallization time, and ratios of NaOH/SiO2, H2O/NaOH, and SiO2/TPABr. The crystallinity, particle size, and morphology were characterized by FT-IR, XRD, particle size analyser, and SEM. The conclusion of the main findings indicated that the XRD patterns of these samples clearly showed a pure phase of MFI structure corresponding to FT-IR spectra with vibration mode at 550 and 1223 cm−1. The highest crystallinity was obtained at reaction time only 6 hours with the mole ratios of NaOH/SiO2, H2O/NaOH and SiO2/TPABr as 0.24, 155, and 30, respectively. When SG was used as a silica source, it was found that the particle size was smaller than that from RHA. The morphologies of all silicalite samples were coffin and cubic-like shape.

  16. The Utilization of Bottom Ash Coal for Briquette Products by Adding Teak Leaves Charcoal, Coconut Shell Charcoal, and Rice Husk Charcoal

    National Research Council Canada - National Science Library

    Syafrudin, Syafrudin; Zaman, Badrus; Indriyani, Indriyani; Erga, A. Stevie; Natalia, H. Bunga

    2015-01-01

    .... This coal ash is a by-product of coal combustion. This coal ash contains bottom ash. Through this observation, the bottom ash can be processed to be charcoal if added by teak leaves, coconut shell, and rice husk...

  17. Mechanical Properties of Millet Husk Ash Bitumen Stabilized Soil ...

    African Journals Online (AJOL)

    Akorede

    product and consequently produce a cheaper soil block construction without comprising its strength. KEYWORDS: Millet husk ... grasses, widely grown around the World as cereal crops or grains for fodder and human food. Millets are important crops.

  18. Properties of silica from rice husk and rice husk ash and their utilization for zeolite y synthesis

    Directory of Open Access Journals (Sweden)

    Jan-Jezreel F. Saceda

    2011-01-01

    Full Text Available This study compared properties of silica (SiO2 from rice husk (RH and rice husk ash (RHA extracted by acid- and heat-treatment. The SiO2 from RH was in amorphous phase with nearly 100% purity while that from RHA was in crystalline phase with 97.56% purity. Both extracted SiO2 were used in the synthesis of zeolite NaY but that from RH was better due to the efficiency in product recovery and simplicity of extraction. After the NaY was exchanged to NH4Y and calcined to convert to HY, the product did not carry over the textural properties of the parent NaY and NH4Y.

  19. Thermoelectric properties and nanostructures of materials prepared from rice husk ash

    Energy Technology Data Exchange (ETDEWEB)

    Pukird, S.; Tipparach, U.; Kasian, P. [Ubon Ratchathani Univ., Ubon Ratchathani (Thailand). Dept. of Physics; Limsuwan, P. [King Mongkut' s Univ. of Technology Thonburi, Bangkok (Thailand). Dept. of Physics

    2009-07-01

    Thailand produces large amounts of agricultural residues such as rice husk and coconut shells. Rice husk is considered to be a potential source for solar grade silicon. Studies have shown that reasonably pure polycrystalline silicon can be prepared from rice husk white ash by a metallothermic reduction process. This paper reported on a study that investigated the thermoelectric properties of ceramic material prepared by mixing silica from rice husk ash and carbon obtained from coconut shell charcoal. The thermoelectric properties of the materials were examined along with their microstructures. The materials were made from burning rice husk ash and coconut shell at different temperatures and then doped with metal oxides. Pellets were heated at temperature of 700 degrees C for 1-3 hours. The voltage on both sides of the pellets was observed. The electromotive force was found when different temperatures were applied on both sides of the pellet specimens. The Seebeck coefficient was then calculated. The results showed that these materials can be used as thermoelectric devices. Scanning electron microscope (SEM) and energy dispersive X-rays (EDX) were used to investigate the source of materials and the products on the substrates. The images of SEM and EDX showed nanostructures of materials such as nanowires, nanorods and nanoparticles of the products and sources. 22 refs., 2 tabs., 9 figs.

  20. Alkali-activated binder containing wastes: a study with rice husk ash and red ceramic

    Directory of Open Access Journals (Sweden)

    R. H. Geraldo

    Full Text Available Abstract In addition to several positive aspects in technical properties, geopolymeric binders have considerable advantages in the environmental point of view, with lower energy consumption and lower CO2 emission. In this study, it was conducted an overview about the utilized materials by some Brazilian researchers in geopolymers production, and also an experiment employing two types of wastes (red ceramic waste and rice husk ash. The compressive strength of the resulting material developed very fast, reaching a value of 11 MPa after one day. The microstructure was evaluated by scanning electron microscopy, revealing a compact microstructure and the presence of starting materials from the red ceramic waste that not completely reacted. The results indicated the feasibility of producing geopolymeric material without using commercial sodium silicate and cured at room temperature, showing an option for building materials production with lower environmental impacts.

  1. Environmentally-Friendly Dense and Porous Geopolymers Using Fly Ash and Rice Husk Ash as Raw Materials

    Directory of Open Access Journals (Sweden)

    Daniele Ziegler

    2016-06-01

    Full Text Available This paper assesses the feasibility of two industrial wastes, fly ash (FA and rice husk ash (RHA, as raw materials for the production of geopolymeric pastes. Three typologies of samples were thus produced: (i halloysite activated with potassium hydroxide and nanosilica, used as the reference sample (HL-S; (ii halloysite activated with rice husk ash dissolved into KOH solution (HL-R; (iii FA activated with the alkaline solution realized with the rice husk ash (FA-R. Dense and porous samples were produced and characterized in terms of mechanical properties and environmental impact. The flexural and compressive strength of HL-R reached about 9 and 43 MPa, respectively. On the contrary, the compressive strength of FA-R is significantly lower than the HL-R one, in spite of a comparable flexural strength being reached. However, when porous samples are concerned, FA-R shows comparable or even higher strength than HL-R. Thus, the current results show that RHA is a valuable alternative to silica nanopowder to prepare the activator solution, to be used either with calcined clay and fly ash feedstock materials. Finally, a preliminary evaluation of the global warming potential (GWP was performed for the three investigated formulations. With the mix containing FA and RHA-based silica solution, a reduction of about 90% of GWP was achieved with respect to the values obtained for the reference formulation.

  2. Partial oxidation of methane to methanol over catalyst ZSM-5 from coal fly ash and rice husk ash

    Directory of Open Access Journals (Sweden)

    Mirda Yanti Fusia

    2017-01-01

    Full Text Available Methane is one of the greenhouse gases that can be converted into liquid fuels such as methanol to retain most of the energy of methane and produce a cleaner environment. The conversion of methane to methanol using ZMS-5 represents a breakthrough in the utilization of methane. However, material sources for zeolite synthesis as catalyst usually are pro-analysis grade materials, which are expensive. Therefore, in this research, coal fly ash and rice husk ash were used as raw materials for mesoporous ZSM-5 zeolite synthesis. First, coal fly ash and rice husk were subjected to pre-treatment to extract silicate (SiO44− and aluminate (AlO45− and impurities separation. The ZSM-5 zeolite was synthesized through hydrothermal treatment using two types of templates. After ZSM-5 was synthesized, it was modified with Cobalt through impregnation method. The catalytic activity of both ZSM-5 and Co/ZSM-5 zeolites as heterogeneous catalysts in partial oxidation of methane were preliminary tested and compared with that commercial one. The result showed that the zeolite catalyst ZSM-5 from fly ash coal and rice husk ash has the potential to be used as catalysts in the partial oxidation of methane to methanol.

  3. Effect of carbide waste on the properties of rice husk ash concrete ...

    African Journals Online (AJOL)

    The impact of carbide waste,CW on the strength of concrete made with cement partially replaced with Rice Husk Ash,RHA for use in rigid pavement was investigated. Oxide composition analysis of CW and RHA confirm their status as non pozzolanic material rich in CaO component and pozzolanic materials, respectively.

  4. Effect of rice husk ash on some geotechnical properties of lateritic

    African Journals Online (AJOL)

    hp

    ABSTRACT. The study is an investigation into the effect of rice husk ash (RHA) on some geotechnical properties of a lateritic soil classified as A-2-6 (0) or SW for sub-grade purposes. The investigation includes evaluation of properties such as compaction, consistency limits and strength of the soil with RHA content of 5%, ...

  5. rice-husk ash-carbide-waste stabilization of reclaimed asphalt

    African Journals Online (AJOL)

    user

    2016-07-03

    Jul 3, 2016 ... This paper present results of the laboratory evaluation of the characteristics of carbide waste and rice husk ash stabilized reclaimed asphalt pavement waste with a view to determine its suitability for use as flexible pavement material. The mixtures were subjected to British Standard heavy compactive effort ...

  6. Effect of rice-husk ash on exchange acidity, growth and yield of ...

    African Journals Online (AJOL)

    Response of groundnut grown on acidic soil to rice-husk ash applied at 0, 1, 2, 3 and 4 t ha-1 was studied in two field experiments in 2005 and 2006 at Ishiagu in the derived savanna zone of southeast Nigeria. Treatments were fitted in a randomized complete block design (RCBD) replicated three times. Effects of treatments ...

  7. the suitability of lime rice husk ash cement as construction material

    African Journals Online (AJOL)

    NIJOTECH

    potassium oxide and sodium oxide in the Portland cement to the values found in the rice husk ash a new product, "Artificial Lime Rice ... successful reduction of the high percentage of silica, potassium oxide and sodium oxide to the level present in ordinary ..... cement shows a unique trend of strength increase with time and ...

  8. Performance evaluation of cement-stabilized pond ash-rice husk ash-clay mixture as a highway construction material

    Directory of Open Access Journals (Sweden)

    Deepak Gupta

    2017-02-01

    Full Text Available This paper reports the results of an investigation carried out on clay soil stabilized with pond ash (PA, rice husk ash (RHA and cement. Modified Proctor compaction tests were performed in order to investigate the compaction behavior of clay, and California bearing ratio (CBR tests were performed to determine the strength characteristics of clay. For evaluation purpose, the specimens containing different amounts of admixtures were prepared. Clay was replaced with PA and RHA at a dosage of 30%–45% and 5%–20%, respectively. The influence of stabilizer types and dosages on mechanical properties of clay was evaluated. In order to study the surface morphology and crystallization characteristics of the soil samples, scanning electron microscopy (SEM and X-ray diffraction (XRD analyses were carried out, respectively. The results obtained indicated a decrease in the maximum dry density (MDD and a simultaneous increase in the optimum moisture content (OMC with the addition of PA and RHA. Multiple linear regression analysis (MLRA showed that the predicted values of CBR tests are in good agreement with the experimental values. Developed stabilized soil mixtures showed satisfactory strength and can be used for construction of embankments and stabilization of sub-grade soil. The use of locally available soils, PA, RHA, and cement in the production of stabilized soils for such applications can provide sustainability for the local construction industry.

  9. PALM KERNEL HUSK ASH (PKHA) AS AN ADMIXTURE ...

    African Journals Online (AJOL)

    will reduce the cost of cement in concrete con- struction works and be of great advantage in the disposal of the palm kernel husk from the palm oil production mills. Also the effect of the PKHA on strength de- velopment was carried out by determining the compressive Strength tests of the same mix- tures after 7 and 28 days ...

  10. Performance at high temperature of alkali-activated slag pastes produced with silica fume and rice husk ash based activators

    National Research Council Canada - National Science Library

    Bernal, S. A; Rodríguez, E. D; Mejía de Gutiérrez, R; Provis, J. L

    2015-01-01

    This study assessed the mechanical properties, and structural changes induced by high temperature exposure, of alkali-silicate activated slag cements produced with sodium silicates derived from silica fume (SF) and rice husk ash (RHA...

  11. Comparison between rice husk ash grown in different regions for stabilizing fly ash from a solid waste incinerator.

    Science.gov (United States)

    Benassi, L; Bosio, A; Dalipi, R; Borgese, L; Rodella, N; Pasquali, M; Depero, L E; Bergese, P; Bontempi, E

    2015-08-15

    The Stabilization of heavy metals from municipal solid waste incineration (MSWI) fly ash by rice husk ash (RHA) is under intense study as an effective strategy to recover and reuse industrial and agricultural waste together. We compare the metal entrapment performances of RHA from different Asian rice sources – namely from Japonica rice grown in Italy and Indica rice grown in India – Physicochemical and morphological characterization of the final stabilized material show that the same thermal treatment may result in marked structural differences in the silica contained in the two RHA. Remarkably, one of them displays a crystalline silica content, although obtained by a thermal treatment below 800 °C. We also find that the presence of an alkali metal ion (potassium) in the rice husk plays a crucial role in the attainment of the final silica phase. These physicochemical differences are mirrored by different stabilization yields by the two RHA. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Modification of Silica Rice Husk Ash to Solid Ammonium Sulphate for Second Generation Biofuels Productions

    Directory of Open Access Journals (Sweden)

    Kasim Mohammed Hello

    2014-01-01

    Full Text Available A new approach has been demonstrated for the synthesis of solid ammonium sulphate attached to silica rice husk ash. The 3-(aminopropyltriethoxysilane was immobilized onto silica at room temperature to functionalize the silica with ammine end groups (–NH2. The amine group was sulphated with sulphuric acid to produce a novel micro-rod-like shaped acidic catalyst (as seen with TEM designated RHNH3SO4H (RH = rice husk. The TGA analysis shows that the catalyst is stable at temperatures below 200°C. The acidity measurement of the catalyst indicates that it has Brønsted acid sites. Cellulose extracted from waste of rice husk and cellulose extracted from office paper were hydrolysed to glucose in 6 h, and the glucose was hydrolysed afterwards to other products within 13 h. The catalyst is reusable many times without a significant loss of catalytic activity.

  13. GROUND NUT HUSK ASH (GHA) AS A PARTIAL REPLACEMENT ...

    African Journals Online (AJOL)

    NIJOTECH

    %, 2%, 4%, 6%, 8% and 10% ash ... Groundnut is an important cash crop produced in large quantity in Nigeria. The production of ground nut ... that ash replacement level of more than 10% is not recommended. The results of water absorption ...

  14. Reuse of Coconut Shell, Rice Husk, and Coal Ash Blends in Geopolymer Synthesis

    Science.gov (United States)

    Walmiki Samadhi, Tjokorde; Wulandari, Winny; Prasetyo, Muhammad Iqbal; Rizki Fernando, Muhammad

    2017-10-01

    Mixtures of biomass and coal ashes are likely to be produced in increasing volume as biomass-based energy production is gaining importance in Indonesia. This work highlights the reuse of coconut shell ash (CSA), rice husk ash (RHA), and coal fly ash (FA) for geopolymer synthesis by an activator solution containing concentrated KOH and Na2SiO3. Ash blend compositions are varied according to a simplex-centroid mixture experimental design. Activator to ash mass ratios are varied from 0.8 to 2.0, the higher value being applied for ash compositions with higher Si/Al ratio. The impact of ash blend composition on early strength is adequately modeled by an incomplete quadratic mixture model. Overall, the ashes can produce geopolymer mortars with an early strength exceeding the Indonesian SNI 15-2049-2004 standard minimum value of 2.0 MPa. Good workability of the geopolymer is indicated by their initial setting times which are longer than the minimum value of 45 mins. Geopolymers composed predominantly of RHA composition exhibit poor strength and excessive setting time. FTIR spectroscopy confirms the geopolymerization of the ashes by the shift of the Si-O-Si/Al asymmetric stretching vibrational mode. Overall, these results point to the feasibility of geopolymerization as a reuse pathway for biomass combustion waste.

  15. Effect of rice-husk ash on exchange acidity, growth and yield of ...

    African Journals Online (AJOL)

    Effect of rice-husk ash on exchange acidity, growth and yield of groundnut ( Arachis hypogaea l.) in an acid ultisol. ... in an acid ultisol. D.O Nottidge, R.B Balogun, N.R Njoku ... Significant increases (P < 0.01) in soil P, K and Ca status relate significantly (P = 0.05) to patterns of growth and kernel yield of the crop. The 3 t ha-1 ...

  16. Ultrasonic and conventional synthesis of NaA zeolite from rice husk ash

    Science.gov (United States)

    Farías, T.; de Ménorval, LC; Picazo, O.; Jordán, R.

    2017-01-01

    In the present work, a simple synthetic route for the production of single phase NaA zeolite is demonstrated. Rice husk ash (RHA) as alternative silica source was employed for the synthesis by conventional hydrothermal and non-conventional ultrasound methods. The zeolite was also synthesized using commercially available silicate for comparison. The effect of the reaction time (2, 4 and 6 h) at a fixed temperature of 70 °C was investigated. The elemental, structural and morphological characterization of the ashes and the synthesized zeolites was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and thermogravimetric analysis (TG/DSC).

  17. Preparation and characterization of electron-beam treated HDPE composites reinforced with rice husk ash and Brazilian clay

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, A.V., E-mail: angelortiz@ipen.br [Nuclear and Energy Research Institute, IPEN-CNEN/SP Av. Prof. Lineu Prestes 2242, São Paulo, SP 05508-000 (Brazil); Teixeira, J.G.; Gomes, M.G.; Oliveira, R.R. [Nuclear and Energy Research Institute, IPEN-CNEN/SP Av. Prof. Lineu Prestes 2242, São Paulo, SP 05508-000 (Brazil); Díaz, F.R.V. [Metallurgical and Materials Engineering Department, Polytechnic School, University of São Paulo Av. Prof. Mello de Morais 2463, São Paulo, SP 05508-900 (Brazil); Moura, E.A.B. [Nuclear and Energy Research Institute, IPEN-CNEN/SP Av. Prof. Lineu Prestes 2242, São Paulo, SP 05508-000 (Brazil)

    2014-08-15

    Highlights: • We examine changes in HDPE properties when waste and clay are used as reinforcement. • The addition of only 3% of clay leads to important gains in HDPE properties. • The use of electron-beam contributes to greater improvements in material properties. • We observe 85% of cross-linking degree for the HDPE when treated with e-beam. - Abstract: This work evaluates the morphology, mechanical and thermo-mechanical properties of high density polyethylene (HDPE) composites. HDPE reinforced with rice husk ashes (80:20 wt%), HDPE reinforced with clay (97:3 wt%) and HDPE reinforced with both rice husk ashes and clay(77:20:3 wt%) were obtained. The Brazilian bentonite chocolate clay was used in this study. This Brazilian smectitic clay is commonly used to produce nanocomposites. The composites were produced by melting extrusion process and then irradiation was carried out in a 1.5 MeV electron-beam accelerator (room temperature, presence of air). Comparisons using the irradiated and non-irradiated neat polymer, and the irradiated and non-irradiated composites were made. The materials obtained were submitted to tensile, flexural and impact tests. Additionally HDT, SEM and XRD analyses were carried out along with the sol–gel analysis which aimed to assess the cross-linking degree of the irradiated materials. Results showed great improvement in most HDPE properties and a high cross-linking degree of 85% as a result of electron-beam irradiation of the material.

  18. Experimental Study on Rise Husk Ash & Fly Ash Based Geo-Polymer Concrete Using M-Sand

    Science.gov (United States)

    Nanda Kishore, G.; Gayathri, B.

    2017-08-01

    Serious environmental problems by means of increasing the production of Ordinary Portland cement (OPC), which is conventionally used as the primary binder to produce cement concrete. An attempt has been made to reduce the use of ordinary Portland cement in cement concrete. There is no standard mix design of geo-polymer concrete, an effort has been made to know the physical, chemical properties and optimum mix of geo-polymer concrete mix design. Concrete cubes of 100 x 100 x 100 mm were prepared and cured under steam curing for about 24 hours at temperature range of 40°C to 60°C. Fly ash is replaced partially with rice husk ash at percentage of 10%, 15% and 25%. Sodium hydroxide and sodium silicate are of used as alkaline activators with 5 Molar and 10 Molar NaOH solutions. Natural sand is replaced with manufacture sand. Test results were compared with controlled concrete mix of grade M30. The results shows that as the percentage of rice husk ash and water content increases, compressive strength will be decreases and as molarity of the alkaline solution increases, strength will be increases.

  19. Evaluation of the Performance and Microstructure of Ecofriendly Construction Bricks Made with Fly Ash and Residual Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    Chao-Lung Hwang

    2015-01-01

    Full Text Available This research presents the engineering performance and the microstructural characterization of ecofriendly construction bricks that were produced using a binder material made from a mixture of class-F fly ash (FA and residual rice husk ash (RHA. Unground rice husk ash (URHA was used as a partial fine aggregate substitute (0–40%. The solid bricks of 220 × 105 × 60 mm in size were prepared by mixing FA and RHA with an alkaline solution and fine aggregates, formed by compressing the mixture in a steel mold under 35 MPa of forming pressure, and then cured at 35°C and 50% relative humidity until the required testing ages. The tests of compressive strength, water absorption, and bulk density were conducted in accordance with relevant Vietnamese standards in order to estimate the effect of the URHA content on the engineering performance of the hardened bricks. Scanning electron microscopy (SEM, X-ray diffraction (XRD, and Fourier transform infrared spectroscopy (FTIR were performed to determine the microstructure and the phase composition of the brick samples. The results show that properties of these bricks conformed to relevant Vietnamese standards. Therefore, FA and RHA are potential candidate materials for producing ecofriendly construction bricks using geopolymerization technology.

  20. Strength and durability performance of alkali-activated rice husk ash geopolymer mortar.

    Science.gov (United States)

    Kim, Yun Yong; Lee, Byung-Jae; Saraswathy, Velu; Kwon, Seung-Jun

    2014-01-01

    This paper describes the experimental investigation carried out to develop the geopolymer concrete based on alkali-activated rice husk ash (RHA) by sodium hydroxide with sodium silicate. Effect on method of curing and concentration of NaOH on compressive strength as well as the optimum mix proportion of geopolymer mortar was investigated. It is possible to achieve compressive strengths of 31 N/mm(2) and 45 N/mm(2), respectively for the 10 M alkali-activated geopolymer mortar after 7 and 28 days of casting when cured for 24 hours at 60°C. Results indicated that the increase in curing period and concentration of alkali activator increased the compressive strength. Durability studies were carried out in acid and sulfate media such as H2SO4, HCl, Na2SO4, and MgSO4 environments and found that geopolymer concrete showed very less weight loss when compared to steam-cured mortar specimens. In addition, fluorescent optical microscopy and X-ray diffraction (XRD) studies have shown the formation of new peaks and enhanced the polymerization reaction which is responsible for strength development and hence RHA has great potential as a substitute for ordinary Portland cement concrete.

  1. Non-isothermal degradation kinetics of filled with rise husk ash polypropene composites

    Directory of Open Access Journals (Sweden)

    2008-02-01

    Full Text Available The thermal stability and kinetics of non-isothermal degradation of polypropene and polypropene composites filled with 20 mass% vigorously grounded and mixed raw rice husks (RRH, black rice husks ash (BRHA, white rice husks ash (WRHA and Aerosil Degussa (AR were studied. The calculation procedures of Coats – Redfern, Madhysudanan et al., Tang et al., Wanjun et al. and 27 model kinetic equations were used. The kinetics of thermal degradation were found to be best described by kinetic equations of n-th order (Fn mechanism. The kinetic parameters E, A, ΔS≠, ΔH≠and ΔG≠for all the samples studied were calculated. The highest values of n, E and A were obtained for the composites filled with WRHA and AR. A linear dependence between lnA and E was observed, known also as kinetic compensation effect. The results obtained were considered enough to conclude that the cheap RRH and the products of its thermal degradation BRHA and WRHA, after vigorously grounding and mixing, could successfully be used as fillers for polypropene instead of the much more expensive synthetic material Aerosil to prepare various polypropene composites.

  2. Hydro-Physical Properties of a Typic Hapludult under the Effect of Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    Gláucia Oliveira Islabão

    2016-01-01

    Full Text Available ABSTRACT The combustion of rice husk generates a partially burnt mixture called rice husk ash (RHA that can be used as a source of nutrients to crops and as a conditioner of soil physical properties. The objective of this study was to evaluate the effect of RHA levels on the hydro-physical properties of a Typic Hapludult. The experimental design was composed of random blocks with four replications, which comprised plots of 24 m2 and treatments with increasing RHA rates: 0, 40, 80 and 120 Mg ha-1. Undisturbed soil samples were collected in the soil layers of 0.00-0.10 and 0.10-0.20 m after nine months of RHA application, using steel cylinders (0.03 m of height and 0.047 m of diameter. These samples were used to determine soil bulk density (Bd, total soil porosity (TP, soil macroporosity (Ma, soil microporosity (Mi and the available water capacity (AWC. Disturbed soil samples were collected to determine the stability of soil aggregates in water, mean weight diameter of water stable aggregates (MWD, and soil particle size distribution. The results show that, as the RHA rate increased in the soil, Bd values decreased and TP, Ma and MWD values increased. No effect of RHA was found on Mi and AWC values. The effects of RHA on the S parameter (Dexter, 2004, precompression stress and compression index (Dias Junior and Pierce, 1995 values are consistent those shown for density and total porosity. Rice husk ash was shown to be an efficient residue to improve soil physical properties, mainly at rates between 40 and 80 Mg ha-1. Rice husk ash reduces bulk density and increases total porosity, macroporosity and soil aggregation, but does not affect microporosity, field capacity, permanent wilting point, and available water capacity of the soil. The effect of rice husk ash on the S parameter, precompression stress and index compressibility coefficient values are consistent with those observed for the bulk density and total porosity.

  3. Determination of Relationship between Dielectric Properties, Compressive Strength, and Age of Concrete with Rice Husk Ash Using Planar Coaxial Probe

    Directory of Open Access Journals (Sweden)

    Piladaeng Nawarat

    2016-02-01

    Full Text Available This paper deals with an investigation of the dielectric properties of concretes that includes rice husk ash using a planar coaxial probe. The planar coaxial probe has a planar structure with a microstrip and coaxial features. The measurement was performed over the frequency range of 0.5-3.5 GHz, and concrete specimens with different percentages of rice husk ash were tested. The results indicated that the dielectric constant of the concretes was inversely proportional to the frequency, while the conductivity was proportional to the frequency. The dielectric constant decreased with the increasing age of the concrete at the frequency of 1 GHz. The conductivity of the concrete decreased with the increasing age of the concrete at the frequency of 3.2 GHz. In addition, the dielectric constant and the conductivity decreased when the compressive strength increased. It was also shown that the obtained dielectric properties of the concrete could be used to investigate the relationship between the compressive strength and age of the concrete. Moreover, there is an opportunity to apply the proposed probe to determine the dielectric properties of other materials.

  4. Esterification free fatty acid in sludge palm oil using ZrO2/SO42- - rice husk ash catalyst

    Science.gov (United States)

    Hidayat, Arif; Sutrisno, Bachrun

    2017-05-01

    Indonesia, as one of the biggest palm oil producers and exporters in the world, is producing large amounts of low-grade oil such as sludge palm oil (SPO) from palm oil industries. The use of SPO can lower the cost of biodiesel production significantly, which makes SPO a highly potential alternative feedstock for biodiesel production. In this paper, the esterification of free fatty acid on sludge palm oil was studied using rice husk ash as heterogeneous solid catalysts. Heterogeneous solid catalysts offer significant advantages of eliminating separation, corrosion, toxicity and environmental problems. In this paper the esterification of SPO, a by-product from palm oil industry, in the presence of modified rice husk ash catalysts was studied. The rice husk ash catalysts were synthesized by impregnating of Zirconia (Zr) on rice husk ash followed by sulfonation. The rice husk ash catalysts were characterized by using different techniques, such as FT-IR, XRD, and porous analysis. The effects of the mass ratio of catalyst to oil (1 - 10%), the molar ratio of methanol to oil (4:1 - 10:1), and the reaction temperature (40 - 60°C) were studied for the conversion of free fatty acids (FFAs) to optimize the reaction conditions. The results showed that the optimal conditions were an methanol to oil molar ratio of 10:1, the amount of catalyst of 10%w, and reaction temperature of 60°C.

  5. Fabrication and Performance Test of Aluminium Alloy-Rice Husk Ash Hybrid Metal Matrix Composite as Industrial and Construction Material

    Directory of Open Access Journals (Sweden)

    Md. Rahat Hossain

    2017-12-01

    Full Text Available Aluminium matrix composites (AMCs used extensively in various engineering fields due to their exceptional mechanical properties. In this present study, aluminium matrix composites (AMCs such as aluminium alloy (A356 reinforced with rice husk ash particles (RHA are made to explore the possibilities of reinforcing aluminium alloy. The stir casting method was applied to produce aluminium alloy (A356 reinforced with various amounts of (2%, 4%, and 6% rice husk ash (RHA particles. Physical treatment was carried out before the rice husk ash manufacturing process. The effect of mechanical strength of the fabricated hybrid composite was investigated. Therefore, impact test, tensile stress, compressive stress, and some other tests were carried out to analyse the mechanical properties. From the experimental results, it was found that maximum tensile, and compressive stress were found at 6% rice husk ash (RHA and aluminium matrix composites (AMCs. In future, the optimum percentages of rice husk ash (RHA to fabricate the hybrid composites will be determined. Also, simulation by finite element method (FEM will be applied for further investigation.

  6. Comparing dry ashing and wet oxidation methods. The case of the rice husk (Oryza sativa L.).

    Science.gov (United States)

    Sun, Xiuping; Wu, Yan; Wang, Changsui; Hill, David V

    2012-09-01

    Experiments were conducted to determine the effects that different methods for the preparation of modern plant samples have on the resulting phytoliths using rice husks (Oryza sp.). The methods that are commonly used in phytolith extraction include (1) dry ashing, (2) acid extraction (3) a combination of both techniques. The results showed that processing methods have an impact on the morphology of two subspecies of rice phytoliths, dry ashing producing more conjoined cell phytoliths or multicells phytoliths than acid extraction. Using a combination of both methods resulted in the presence of fewer conjoined cells than dry ashing alone, but more conjoined cells than acid extraction. Alternative explanations are proposed to explain the formation of conjoined phytolith cells. Copyright © 2012 Wiley Periodicals, Inc.

  7. Stabilisation of Clay Soil with Lime and Melon Husk Ash for use in Farm Structures

    Directory of Open Access Journals (Sweden)

    I. S. Mohammed

    2014-08-01

    Full Text Available The rising cost of traditional stabilising agents and the need for economical utilisation of industrial and agricultural waste for beneficial engineering purposes has encouraged an investigation into the stabilization of clay soil with lime and melon husk ash. The chemical composition of the melon husk ash that was used in stabilising clay soil was determined. The clay soil was divided into two parts, one part was used to determine the index properties while the other part was treated at British Standard Light (BSL compaction energy with 0 %, 2 %, 4 %, 6 % and 8 % melon husk ash by dry weight of the soil and each was admixed with 2 %, 4 %, 6 % and 8 % lime. The stabilised clay soil was cured for 7, 14 and 28 days before the unconfined compressive strength were determined while the coefficients of permeability of the stabilised clay soil were also determined at 28 days of curing. The data obtained from the experiment was subjected to analysis of variance to examine the significance at 5% level. Results showed that the natural clay soil belong to A-7-6 or CH (clay of high plasticity in the American Association of State Highway Transportation Official (AASHTO and Unified Soil Classification System (1986. The chemical composition of the ash had aluminum oxide, iron oxide and silicon dioxide values of 18.5%, 2.82% and 51.24% respectively. The unconfined compressive strength and coefficient of permeability of the natural clay soil was determined to be 285 kN/m2 and 1.45 x 10-5 cm/s, respectively. Increase in melon husk ash and lime percent increases the unconfined compressive strength (UCS of the stabilised clay soil significantly (p < 0.05 and decrease the coefficient of permeability when compared with the natural clay soil. The peak values of unconfined compressive strength for 7, 14 and 28 days of curing are 1200 kN/m2, 1598 kN/m2 and 1695 kN/m2 respectively at 6% MHA and 8% lime content while the lowest value for coefficient of permeability was 0

  8. Removal of Lead(II) Ions from Aqueous Solution Using L. Seed Husk Ash as a Biosorbent.

    Science.gov (United States)

    Shi, Bingfang; Zuo, Weiyuan; Zhang, Jinlei; Tong, Haijuan; Zhao, Jinhe

    2016-05-01

    The removal of heavy metals, especially from wastewater, has attracted significant interest because of their toxicity, tendency to bioaccumulate, and the threat they pose to human life and the environment. Many low-cost sorbents have been investigated for their biosorption capacity toward heavy metals. However, there are no reports available on the removal of Pb(II) from aqueous solution by of L. seed husk ash. In this work, use of seed husk ash for the removal of Pb(II) from wastewater was investigated as a function of contact time and the initial pH of the solution. Kinetics and equilibrium constants were obtained from batch experiments. Our study shows that the adsorption process follows pseudo-second-order kinetics. Moreover, the Langmuir absorption model gave a better fit to the experimental data than the Freundlich equation. The maximum adsorption capacity of the husk ash was 263.10 mg g at 298 K and pH 5.0, and this is higher than the previously reported data obtained using other sorbents. The results obtained confirm that seed husk ash is an effective sorbent for the removal of Pb(II) from aqueous solution. Analysis of infrared spectra of the husk ash after absorption of Pb(II) suggested that OH, C=O, C-O, Si-O-Si, and O-Si-O groups were important for the Pb(II) ion removal. Moreover, practical tests on this biosorbent for Pb(II) removal in real wastewater samples successfully demonstrated that seed husk ash constitutes an efficient and cost-effective technology for the elimination of heavy metals from industrial effluent. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  9. Removal of copper (II) ion from aqueous solution using zeolite Y synthesized from rice husk ash: Equilibrium and kinetic study

    Science.gov (United States)

    Tuyen, Nguyen Thi Kim; Nhan, Do Nguyen Thanh; Nhat, Trieu Thi; An, Ngo Thanh; Long, Nguyen Quang

    2017-09-01

    Zeolite Y was synthesized from silica of rice-husk ash using hydrothermal process. The crystalline structure FAU of zeolite Y was characterized by X-ray diffraction (XRD). Surface's area of the catalyst was determined by physic-adsorption method using BET model. The zeolite was examined for possibility of Cu2+ adsorbent by an ion-exchange mechanism. Various adsorption isotherm models, such as Langmuir, Freundlich and Dubinin-Radushkevich were tested for equilibrium study. The integration method was applied to find out the possible kinetic equation of the Cu2+ adsorption on the zeolite Y which obtained from cheap and locally available rice husk ash.

  10. Utilization of Palm Oil Fuel Ash and Rice Husks in Unfired Bricks for Sustainable Construction Materials Development

    Directory of Open Access Journals (Sweden)

    Saleh A.M

    2014-01-01

    Full Text Available The production of sustainable construction component could prevent and control the pollution and environmental degradation in Malaysia. This is a key area in Malaysia’s Green Strategies (Ministry of Science, Technology and the environment, 2002. This paper reports on the laboratory investigation to establish the potential of utilizing Palm Oil Fuel Ash (POFA and Rice Husk (RH in developing green construction components. Malaysian Palm Oil Council (MPOC reported that currently Malaysia’s contribution to world palm oil production is 39% and has taken 44% of world exports. Consequently it will increase the POFA production in palm oil manufacturing and this waste sometimes dispose in open area near the factory. On the other hand Malaysia also producing more 300k hectares of paddy production, thus rice husk is also a concern as an agricultural waste. The research objective is to study on the potential of utilizing of agricultural waste in developing of green bricks. This research involved laboratory investigations. In this research 2% - 10% of POFA and 1% - 5% RH were used in the mix composition of the brick’s weight. Addition of POFA was aimed to reduce the cement usage and RH was added to reduce sand in the bricks. The bricks were manually pressed in Materials Laboratory in Faculty of Architecture, Planning and Surveying, UiTM Shah Alam. The result showed that the addition of POFA and RH are able to reduce the density but in contrast the compressive strength were decrease compare to the control unit.

  11. Synthesis of belite cement from nano-silica extracted from two rice husk ashes.

    Science.gov (United States)

    Sinyoung, Suthatip; Kunchariyakun, Kittipong; Asavapisit, Suwimol; MacKenzie, Kenneth J D

    2017-04-01

    Nano-silicas extracted from a pure rice husk ash calcined in the laboratory (RHA) and ash from an impure industrial rice husk waste (BRHA), were used to form belite cement by firing with two different calcium sources (calcium carbonate and calcium nitrate). The nano-silica extracted from RHA was highly reactive due to its high pore volume and low activation energy of dehydration. The formation of belite cement from both nano-silicas was studied by firing with two different calcium sources, Ca(NO3)2 and CaCO3 at 800-1100 °C. Both nano-silicas formed the principal phase in belite cement (larnite or β-C2S) at temperatures as low as 800 °C, especially with calcium nitrate as the calcium source. Thus, highly impure BRHA is shown to be very suitable as a starting material for the low-temperature production of belite cement, especially in conjunction with calcium nitrate as the calcium source. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Rice Husk Ash-Derived Silica Nanofluids: Synthesis and Stability Study.

    Science.gov (United States)

    Zhang, Zhiliang; He, Wenxiu; Zheng, Jianzhong; Wang, Guangquan; Ji, Jianbing

    2016-12-01

    Nanofluids, colloidal suspensions consisting of base fluids and nanoparticles, are a new generation of engineering working fluids. Nanofluids have shown great potential in heat/mass transfer applications. However, their practical applications are limited by the high production cost and low stability. In this study, a low-cost agricultural waste, rice husk ash (RHA), was used as a silicon source to the synthesis of silica nanofluids. First, silica nanoparticles with an average size of 47 nm were synthesized. Next, by dispersing the silica nanoparticles in water with ultrasonic vibration, silica nanofluids were formed. The results indicated that the dispersibility and stability of nanofluids were highly dependent on sonication time and power, dispersant types and concentrations, as well as pH; an optimal experiment condition could result in the highest stability of silica nanofluid. After 7 days storage, the nanofluid showed no sedimentation, unchanged particle size, and zeta potential. The results of this study demonstrated that there is a great potential for the use of RHA as a low-cost renewable resource for the production of stable silica nanofluids. Graphical Abstract Rice husk ash was used as a low-cost renewable resource for production of silica nanofluids with high stability.

  13. Esterification free fatty acid in palm fatty acid distillate using sulfonated rice husk ash catalyst

    Science.gov (United States)

    Hidayat, Arif; Sutrisno, Bachrun

    2017-01-01

    Indonesia, as one of the biggest palm oil producers and exporters in the world, is producing large amounts of low-grade oil such as Palm Fatty Acid Distillate (PFAD) from palm oil industries. The use of PFAD can reduce the cost of biodiesel production significantly, which makes PFAD a highly potential alternative feedstock for biodiesel production. In this paper, the esterification of free fatty acid (FFA) on PFAD was studied using rice husk ash (RHA) as heterogeneous catalyst. The rice husk ash catalyst was synthesized by sulfonation using concentrated sulfuric acid. The RHA catalyst were characterized by using different techniques, such as porosity analysis, Fourier transform infrared (FT-IR) spectroscopy, total number of acid sites and elemental analysis. The effects of the molar ratio of methanol to PFAD (1-10%), the molar ratio of methanol to PFAD (4:1-10:1), and the reaction temperature (40-60°C) were studied for the conversion of FFA to optimize the reaction conditions. The results showed that the optimal conditions were an methanol to PFAD molar ratio of 10:1, the catalyst amount of 10 wt% of PFAD, and reaction temperature of 60°C.

  14. Effect of acetic acid on rice seeds coated with rice husk ash

    Directory of Open Access Journals (Sweden)

    Lizandro Ciciliano Tavares

    2013-06-01

    Full Text Available Flooded rice cultivation promotes anaerobic conditions, favoring the formation of short chain organic acids such as acetic acid, which may be toxic to the crop. The objective of this study was to evaluate the effect of acetic acid on rice seeds coated with rice husk ash. The experiment was arranged in a 2 x 5 x 5 factorial randomized design, with two cultivars (IRGA 424 and BRS Querência, five doses of coating material (0, 2, 3,4 e 5 g kg-1 seed and five concentrations of acetic acid (0, 3, 6, 9 and 12 mM, with 4 replications, totaling 50 treatments. The variables first count of germination, germination, shoot and root length, dry weight of shoots and roots were recorded. The results showed that coating rice seeds with rice husk ash up to 5 g kg-1 seed does not influence the performance of rice seeds of cultivars IRGA 424 and BRS Querência when exposed to concentrations of 12 mM acetic acid. The presence of acetic acid in the substrates used for seed germination reduced the vigor and viability of seeds of cultivars IRGA 424 and BRS Querência, as well as seedling development, affecting mainly the roots of BRS Querência.

  15. Accelerated Aging Effect on Epoxy-polysiloxane Polymeric Insulator Material with Rice Husk Ash Filler

    Directory of Open Access Journals (Sweden)

    Rochmadi .

    2012-12-01

    Full Text Available The performances of outdoor polymeric insulators are influenced by environmental conditions. This paper presents the effect of artificial tropical climate on the hydrophobicity, equivalent salt deposit density (ESDD, surface leakage current, flashover voltage, and surface degradation on epoxy-polysiloxane polymeric insulator materials with rice husk ash (RHA. Test samples are made at room temperature vulcanized (RTV of various composition of epoxy-polysiloxane with rice husk ash as filler. The aging was carried out in test chamber at temperature from 50oC to 62oC, relative humidity of 60% to 80%, and ultraviolet (UV  radiation 21.28 w/cm2 in daylight conditions for 96 hours. The experiment results showed that the flashover voltage fluctuates from 34.13 kV up to 40.92 kV and tends to decrease on each variation of material composition. The surface leakage current fluctuates and tends to increase. Test samples with higher filler content result greater hydrophobicity, smaller equivalent salt deposit density, and smaller critical leakage current, which caused the increase of the flashover voltage. Insulator material (RTVEP3 showed the best performance in tropical climate environment. Artificial tropical aging for short duration gives less effect to the surface degradation of epoxy-polysiloxane insulator material.

  16. Development of a Zero-Cement Binder Using Slag, Fly Ash, and Rice Husk Ash with Chemical Activator

    Directory of Open Access Journals (Sweden)

    M. R. Karim

    2015-01-01

    Full Text Available The increasing demand and consumption of cement have necessitated the use of slag, fly ash, rice husk ash (RHA, and so forth as a supplement of cement in concrete construction. The aim of the study is to develop a zero-cement binder (Z-Cem using slag, fly ash, and RHA combined with chemical activator. NaOH, Ca(OH2, and KOH were used in varying weights and molar concentrations. Z-Cem was tested for its consistency, setting time, flow, compressive strength, XRD, SEM, and FTIR. The consistency and setting time of the Z-Cem paste increase with increasing RHA content. The Z-Cem mortar requires more superplasticizer to maintain a constant flow of 110±5% compared with OPC. The compressive strength of the Z-Cem mortar is significantly influenced by the amounts, types, and molar concentration of the activators. The Z-Cem mortar achieves a compressive strength of 42–44 MPa at 28 days with 5% NaOH or at 2.5 molar concentrations. The FTIR results reveal that molecules in the Z-Cem mortar have a silica-hydrate (Si-H bond with sodium or other inorganic metals (i.e., sodium/calcium-silica-hydrate-alumina gel. Therefore, Z-Cem could be developed using the aforementioned materials with the chemical activator.

  17. Rice Husk Ash Cement – An alternative pozzolana cement for ...

    African Journals Online (AJOL)

    The engineering properties of the cement resulting from a mixture of OPC plus RHA and lime plus RHA were satisfactory with addition of up to 50% RHA. The RHA improved greatly the compressive strength of lime. The cost of producing RHA was considered in pricing the resulting binder and it showed that the use of RHA ...

  18. Pozzolanic Reactivity of Silica Fume and Ground Rice Husk Ash as Reactive Silica in a Cementitious System: A Comparative Study.

    Science.gov (United States)

    Xu, Weiting; Lo, Tommy Yiu; Wang, Weilun; Ouyang, Dong; Wang, Penggang; Xing, Feng

    2016-03-01

    This study comparably assessed the pozzolanic effect of silica fume (SF) and ground rice husk ash (RHA) as supplementary cementing materials on the properties of blended cement pastes and concretes. A commonly commercial silica fume (SF) and locally-produced rice husk ash (RHA) samples with two finenesses (one with larger size than cement and the other with smaller size than cement) were used in this study. Material properties of SF and RHA were experimentally characterized. Hydration and mechanical properties of cement pastes incorporating SF and RHA were determined by thermogravimetric analysis (TGA) and compressive strength tests, respectively. Properties of concretes regarding workability, mechanical property, durability, and microstructure were evaluated. Results showed that, although the finely ground RHA used in this study possessed lower SiO₂ content and higher particle size compared to SF, it exhibited comparable pozzolanic reactivity with SF due to the nano-scale pores on its each single particle, leading to a higher specific surface area. The optimal replacement levels of SF and RHA were 10% by weight of cement in pastes and concretes. Although addition of SF and RHA led to a significant reduction in slump for the fresh mixtures, inclusion of up to 30% of SF or 15% of ground RHA did not adversely affect the strength of concretes. At the same mix, incorporation of finely-ground RHA in cement composites provided comparable mechanical properties, hydration degree, and durability with SF blended cement composites, owing to the porous structure and high specific surface area of RHA particles. Microstructure morphology analysis of concretes explored by scanning electron microscopy (SEM) further validated the strength and the durability test results.

  19. Pozzolanic Reactivity of Silica Fume and Ground Rice Husk Ash as Reactive Silica in a Cementitious System: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Weiting Xu

    2016-03-01

    Full Text Available This study comparably assessed the pozzolanic effect of silica fume (SF and ground rice husk ash (RHA as supplementary cementing materials on the properties of blended cement pastes and concretes. A commonly commercial silica fume (SF and locally-produced rice husk ash (RHA samples with two finenesses (one with larger size than cement and the other with smaller size than cement were used in this study. Material properties of SF and RHA were experimentally characterized. Hydration and mechanical properties of cement pastes incorporating SF and RHA were determined by thermogravimetric analysis (TGA and compressive strength tests, respectively. Properties of concretes regarding workability, mechanical property, durability, and microstructure were evaluated. Results showed that, although the finely ground RHA used in this study possessed lower SiO2 content and higher particle size compared to SF, it exhibited comparable pozzolanic reactivity with SF due to the nano-scale pores on its each single particle, leading to a higher specific surface area. The optimal replacement levels of SF and RHA were 10% by weight of cement in pastes and concretes. Although addition of SF and RHA led to a significant reduction in slump for the fresh mixtures, inclusion of up to 30% of SF or 15% of ground RHA did not adversely affect the strength of concretes. At the same mix, incorporation of finely-ground RHA in cement composites provided comparable mechanical properties, hydration degree, and durability with SF blended cement composites, owing to the porous structure and high specific surface area of RHA particles. Microstructure morphology analysis of concretes explored by scanning electron microscopy (SEM further validated the strength and the durability test results.

  20. Bioactivity and Cell Compatibility of β-Wollastonite Derived from Rice Husk Ash and Limestone

    Directory of Open Access Journals (Sweden)

    Roslinda Shamsudin

    2017-10-01

    Full Text Available The aim of this study was to prepare β-wollastonite using a green synthesis method (autoclaving technique without organic solvents and to study its bioactivity. To prepare β-wollastonite, the precursor ratio of CaO:SiO2 was set at 55:45. This mixture was autoclaved for 8 h and later sintered at 950 °C for 2 h. The chemical composition of the precursors was studied using X-ray fluorescence (XRF, in which rice husk ash consists of 89.5 wt % of SiO2 in a cristobalite phase and calcined limestone contains 97.2 wt % of CaO. The X-ray diffraction (XRD patterns after sintering showed that only β-wollastonite was detected as the single phase. To study its bioactivity and degradation properties, β-wollastonite samples were immersed in simulated body fluid (SBF for various periods of time. Throughout the soaking period, the molar ratio of Ca/P obtained was in the range of 1.19 to 2.24, and the phase detected was amorphous calcium phosphate, which was confirmed by scanning electron microscope with energy dispersive X-ray analysis (SEM/EDX and XRD. Fourier-transform infrared spectroscopy (FTIR analysis indicated that the peaks of the calcium and phosphate ions increased when an amorphous calcium phosphate layer was formed on the surface of the β-wollastonite sample. A cell viability and proliferation assay test was performed on the rice husk ash, calcined limestone, and β-wollastonite samples by scanning electron microscope. For heavy metal element evaluation, a metal panel that included As, Cd, Pb, and Hg was selected, and both precursor and β-wollastonite fulfilled the requirement of an American Society for Testing and Materials (ASTM F1538-03 standard specification. Apart from that, a degradation test showed that the loss of mass increased incrementally as a function of soaking period. These results showed that the β-wollastonite materials produced from rice husk ash and limestone possessed good bioactivity, offering potential for biomedical

  1. Effect of Commercial SiO2 and SiO2 from rice husk ash loading on biodegradation of Poly (lactic acid) and crosslinked Poly (lactic acid)

    Science.gov (United States)

    Prapruddivongs, C.; Apichartsitporn, M.; Wongpreedee, T.

    2017-09-01

    In this work, biodegradation behavior of poly (lactic acid) (PLA) and crosslinked PLA filled with two types of SiO2, precipitated SiO2 (commercial SiO2) and SiO2 from rice husk ash, were studied. Rice husks were first treated with 2 molar hydrochloric acid (HCl) to produce high purity SiO2, before burnt in a furnace at 800°C for 6 hours. All components were melted bending by an internal mixer then hot pressed using compression molder to form tested specimens. FTIR spectra of SiO2 and PLA samples were investigated. The results showed the lack of silanol group (Si-OH) of rice husk ash after steric acid surface modification, while the addition of particles can affect the crosslinking of the PLA. For biodegradation test by evaluating total amount of carbon dioxide (CO2) evolved during 60 days incubation at a controlled temperature of 58±2°C, the results showed that the biodegradation of crosslinked PLA occurred slower than the neat PLA. However, SiO2 incorporation enhanced the degree of biodegradation In particular, introducing commercial SiO2 in PLA and crosslinked PLA tended to clearly increase the degree of biodegradation as a consequence of the more accelerated hydrolysis degradation.

  2. Removal of fluoride from drinking water using aluminum hydroxide coated rice husk ash.

    Science.gov (United States)

    Ganvir, Vivek; Das, Kalyan

    2011-01-30

    Fluoride content in groundwater that is greater than the WHO limit of 1.5mg/L, causes dental and skeletal fluorosis. In India, several states are affected with excess fluoride in groundwater. The problem is aggravated due to the lack of appropriate and user friendly defluoridation technology. Several fluoride removal techniques are reported in the literature amongst which the Nalgonda technique and use of activated alumina have been studied extensively. However a simple, efficient and cost effective technology is not available for widespread use in many affected regions. In this paper, we present a novel cost effective defluoridation method that is based on surface modification of rice husk ash (RHA) by coating aluminum hydroxide. RHA is obtained by burning rice/paddy husk which is an abundantly available and is an inexpensive raw material. The results showed excellent fluoride removal efficiency and the adsorption capacity was found to be between 9 and 10mg/g. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Upgrading of bio-oil from the pyrolysis of biomass over the rice husk ash catalysts

    Science.gov (United States)

    Sutrisno, B.; Hidayat, A.

    2016-11-01

    The pyrolysis oils are complex mixtures of organic compounds that exhibit a wide spectrum of chemical functionality, and generally contain some water. Their direct use as fuels may present some difficulties due to their high viscosity, poor heating value, corrosiveness and instability. For possible future use as replacements for hydrocarbon chemical feedstocks and fuels, the liquids will require considerable upgrading to improve its characteristics. By esterification of the bio oil as the upgrading method, the properties of the bio-oil could be improved. In the paper, the upgrading of a bio-oil obtained by pyrolysis was studied over rice husk ash catalysts. The raw bio-oil was produced by pyrolysis of rice husk.From the experiment results, it can be concluded that the densities of upgraded bio-oil were reduced from 1.24 to 0.95 g.cm-3, and the higherheating value increased from 16.0 to 27.2 MJ/kg and the acidity of upgraded bio-oil was also alleviated from 2.3 to 4.4. The results of gas chromatography-mass spectrometry (GC-MS) and FT-IR analysis showed that the ester compounds in the upgraded bio-oil increased. It is possible to improve the properties of bio-oil by esterifying the raw bio-oil.

  4. Effect of rice husk ash mass on sustainability pyrolysis zone of fixed bed downdraft gasifier with capacity of 10 kg/hour

    Science.gov (United States)

    Surjosatyo, Adi; Haq, Imaduddin; Dafiqurrohman, Hafif; Gibran, Felly Rihlat

    2017-03-01

    The formation of pyrolysis sustainability (Sustainable Pyrolysis) is the objective of the gasification process. Pyrolysis zone in the gasification process is the result of the endothermic reaction that get heat from oxidation (combustion) of the fuel with oxygen, where cracking biomass rice husk result of such as charcoal, water vapor, steam tar, and gas - gas (CO, H 2, CH 4, CO 2 and N 2) and must be maintained at a pyrolysis temperature to obtain results plentiful gas (producer gas) or syngas (synthetic gas). Obtaining continuously syngas is indicated by flow rate (discharge) producer gas well and the consistency of the flame on the gas burner, it is highly influenced by the gasification process and the operation of the gasifier and the mass balance (mass balance) between the feeding rate of rice husk with the disposal of ash (ash removal). In experiments conducted is using fixed bed gasifier type downdraft capacity of 10 kg/h. Besides setting the mass of rice husks into the gasifier and disposal arrangements rice husk ash may affect the sustainability of the pyrolysis process, but tar produced during the gasification process causes sticky rice husk ash in the plenum gasifier. Modifications disposal system rice husk ash can facilitate the arrangement of ash disposal then could control the temperature pyrolysis with pyrolysis at temperatures between 500-750 ° C. The experimental study was conducted to determine the effect of mass quantities of rice husk ash issued against sustainability pyrolysis temperature which is obtained at each time disposal of rice husk ash to produce 60-90 grams of ash issued. From some experimental phenomena is expected to be seen pyrolysis and its effect on the flow rate of syngas and the stability of the flame on the gas burner so that this research can find a correlation to obtain performance (performance) gasifier optimal.

  5. Preparation of TiO2/MCM-41 photocatalyst using rice husk ash as silica source

    Science.gov (United States)

    Fatimah, Is; Sopia, Lusi

    2017-03-01

    This work aimed to prepare TiO2/MCM-41 from rice husk ash (RHA) agricultural waste and its application as photocatalyst in dye degradation. The preparation was conducted by two main steps; preparation of MCM-41 and titanium immobilization onto MCM-41. Sol gel method using CTMABr as templating agent was applied in MCM-41 synthesis and as TiO2 precursor, titanium isopropoxide was utilized. The study of physicochemical character change was performed by by X-ray diffraction, IR spectroscopy, BET method and thermogravimetric analysis (TGA). Photocatalytic activity of material was tested in methylene blue photodegradation system. According to the results, it is found that TiO2/MCM-41 has been successfully prepared and shows photocatalytic activity. Kinetic study of the reaction is discussed in this paper.

  6. Experimental Studies on SiC and Rice Husk Ash Reinforced Al Alloy Composite

    Directory of Open Access Journals (Sweden)

    Shivaprakash Y. M.

    2018-01-01

    Full Text Available In this research work Aluminium alloy with Cu (4.5% as the major alloying element is used as the matrix in which SiC and Rice Husk Ash (RHA are dispersed to develop a hybrid composite. The dispersion is done by the motorized stir casting arrangement. The composite is fabricated by varying the proportions of the reinforcements in the base alloy. The composite specimens were tested for density changes, hardness and the wear. The microstructure images showed a uniform dispersion of the reinforcements in the matrix and this resulted in higher strength to weight ratio. The increase in strength of the composite is probably attributed to the increase in the dislocation density. Also, the abrasive wear resistance of the produced composite is found to be superior as compared to the matrix alloy because of the hard-ceramic particles in the reinforcements.

  7. Synthesis and Characterization of Microwave Sintered Silica Xerogel Produced from Rice Husk Ash

    Science.gov (United States)

    Sudiana, I. N.; Mitsudo, S.; Nishiwaki, T.; Susilowati, P. E.; Lestari, L.; Firihu, M. Z.; Aripin, H.

    2016-08-01

    Silica xerogel ceramic produced from rice husk ash (RHA) taken from South East Sulawesi Indonesia has been successfully sintered by using a millimeter waves (MMW) heating system with a 28 GHz gyrotron as radiation source. The ceramic was also sintered by using an electric furnace where served as a comparison. Densification, microstructural, and morphological characterization of the silica were then investigated by using an Archimedes densification measurement method device, a X-ray diffraction (XRD) and a Scanning Electron Microscopy (SEM), respectively. Effect of microwave energy on the properties of silica xerogel ceramic were evaluated and discussed and compared to conventionally sintered results. The notably different densification and microstructure of sintered samples after sintering were found. The results suggest that microwave radiation provides a microwave effect during sintering.

  8. Characterization of upgraded hydrogel biochar from blended rice husk with coal fly ash

    Science.gov (United States)

    Ahmad, Nurul Farhana; Alias, Azil Bahari; Talib, Norhayati; Rashid, Zulkifli Abd; Ghani, Wan Azlina Wan Ab Karim

    2017-12-01

    Rice husk biochar (RB) blended with coal fly ash (CFA) is used as a material to develop hydrogel for heavy metal removal. This combination, namely hydrogel rice husk biochar-coal fly ash (HRB-CFA) composite is synthesized by embedding the biochar into acrylamide (AAM) as monomer, with N,N'-Methylenebisacrylamide (MBA) as crosslinker and ammonium persulfate (APS) as initiator. While activated carbon (AC) remains an expensive material, HRB-CFA is attracting great interest for its use in the absorption of organic contaminants due to its low material cost and importance as renewable source for securing future energy supply in the environmental system. Although the CFA does not have the surface area as high as AC, certain metallic components that are naturally present in the CFA can play the catalytic role in the removal of heavy metal from wastewater. The percentage of heavy metal removal is depends on the parameters that influence the sorption process; the effect of pH solution, dosage of adsorbent, initial concentration of solution, and contact time. The aim of this study is to characterize HRB-CFA by performing several analyses such as the Brunauer-Emmett-Teller (BET), thermogravimetric (TGA) and field emission scanning electron microscopy (FESEM) methods. The results obtained revealed that the best hydrogel ratio is 0.5:0.5 of blended RB and CFA, as proven by BET surface area, pore volume and pore size of 3.5392 m2/g, 0.00849 cm3/g and 90.566 Å, and the surface morphology showed an increase in porosity size.

  9. SÍNTESE DA PENEIRA MOLECULAR MCM-41 DERIVADA DA CINZA DA CASCA DO ARROZ/SYNTHESIS OF MCM-41 MOLECULAR SIEVE DERIVED FROM RICE HUSK ASH

    National Research Council Canada - National Science Library

    R M Braga; N M Teodoro; F M Aquino; J M F Barros; D M A Melo; J C O Freitas

    2013-01-01

    .... In this article, MCM-41 was synthesized from rice husk ash, natural and chemically treated, as alternative sources of silica, called CCA-MCM-41 and CCAL-MCM-41, respectively, with the aim of reusing...

  10. Caracterização física e mecânica de argamassas à base de cimento Portland e cinza de casca de arroz residual Physical and mechanical characterization on Portland cement mortar with rice husk ash addition

    Directory of Open Access Journals (Sweden)

    Michelle S Rodrigues

    2010-04-01

    Full Text Available A casca de arroz, utilizada como fonte de energia em indústrias de beneficiamento de arroz, converte-se, depois da queima, em uma cinza residual. Esse resíduo, ainda sem um destino adequado, é muitas vezes depositado em grandes áreas abertas e provoca elevado impacto ambiental. Este trabalho teve como objetivo avaliar a viabilidade de utilização da cinza de casca de arroz (CCA residual na produção de argamassas, como substituta parcial do cimento. A caracterização da CCA foi realizada por meio da análise de fluorescência de raios-X (composição química, análise do teor de carbono e difração de raios-X; também foi realizada análise granulométrica a laser. Os corpos de prova foram submetidos a dois tipos de exposição: ambientes externo e interno, com duração máxima de cinco meses. Foram realizados os ensaios de resistência à compressão simples e não destrutivo (velocidade do pulso ultrassônico - VPU. Embora as argamassas tenham apresentado bom desempenho mecânico, os ensaios de pozolanicidade indicaram que a cinza de casca de arroz residual utilizada não é uma pozolana, mas pode ser utilizada em matrizes cimentícias como material inerte (filler.Rice husk, employed as an energy source at milling industries in Brazil generates, after burning, a dark ash. This residue is not yet conveniently disposed, being currently dumped on large areas, causing environmental problems. This research intended to evaluate the applications of residual rice husk ashes (RHA as a partial replacement of cement for mortar production. Rice husk ash was chemically characterized through X-ray fluorescence, determination of carbon content, X-ray diffraction, and laser granulometric analysis. Mortar specimens were submitted to two different exposure conditions: internal and external environments at a maximum period of five months. Physical-mechanical testing were compressive strength and ultrasonic pulse velocity (UPV. Although presenting good

  11. Arsenic and fluoride removal by potato peel and rice husk (PPRH) ash in aqueous environments.

    Science.gov (United States)

    Bibi, Sadia; Farooqi, Abida; Yasmin, Azra; Kamran, Muhammad Aqeel; Niazi, Nabeel Khan

    2017-11-02

    Finding appropriate adsorbent may improve the quality of drinking water in those regions where arsenic (As) and fluoride (F-) are present in geological formations. In this study, we evaluated the efficiency of potato peel and rice husk ash (PPRH-ash)-derived adsorbent for the removal of As and F from contaminated water. Evaluation was done in batch adsorption experiments, and the effect of pH, initial adsorbate concentration, contact time, and adsorbent dose were studied. Characteristics of adsorbents were analyzed using scanning electron micropcope (SEM) and Fourier transform infrared (FTIR) spectroscopy. Both the Langmuir and Freundlich isotherm models fitted well for F- and As sorption process. The maximum adsorption capacity of adsorbent for As and F- was 2.17 μg g-1 and 2.91 mg g-1, respectively. The As and Fi removal was observed between pH 7 and 9. The sorption process was well explained with pseudo-second order kinetic model. Arsenic adsorption was not decreased in the presence of carbonate and sulfate. Results from this study demonstrated potential utility of this agricultural biowaste, which could be developed into a viable filtration technology for As and F- removal in As- and F-contaminated water streams.

  12. Study on properties of rice husk ash and its use as cement replacement material

    Directory of Open Access Journals (Sweden)

    Ghassan Abood Habeeb

    2010-06-01

    Full Text Available This paper investigates the properties of rice husk ash (RHA produced by using a ferro-cement furnace. The effect of grinding on the particle size and the surface area was first investigated, then the XRD analysis was conducted to verify the presence of amorphous silica in the ash. Furthermore, the effect of RHA average particle size and percentage on concrete workability, fresh density, superplasticizer (SP content and the compressive strength were also investigated. Although grinding RHA would reduce its average particle size (APS, it was not the main factor controlling the surface area and it is thus resulted from RHA's multilayered, angular and microporous surface. Incorporation of RHA in concrete increased water demand. RHA concrete gave excellent improvement in strength for 10% replacement (30.8% increment compared to the control mix, and up to 20% of cement could be valuably replaced with RHA without adversely affecting the strength. Increasing RHA fineness enhanced the strength of blended concrete compared to coarser RHA and control OPC mixtures.

  13. Effect of Na2SiO3/NaOH on mechanical properties and microstructure of geopolymer mortar using fly ash and rice husk ash as precursor

    Science.gov (United States)

    Saloma, Hanafiah, Elysandi, Debby Orjina; Meykan, Della Garnesia

    2017-11-01

    Geopolymer concrete is an eco-friendly concrete that can reduce carbon emissions on the earth surface because it used industrial waste material such as fly ash, rice husk ash, bagasse ash, and palm oil fuel. Geopolymer is semi-crystalline amorphous materials which has irregular chemical bonds structure. The material is produced by geosynthesis of aluminosilicates and alkali-silicates which produce the Si-O-Al polymer structure. This research used the ratio of fly ash and rice husk ash as precursors e.g. 100:0, 75:25, 50:50, and 25:75. NaOH solutions of 14 M and Na2SiO3 solutions with the variation e.g. 2.5, 2.75, 3.00, and 3.25 were used as activators on mortar geopolymer mixture. The tests of fresh mortar were slump flow and setting time. The optimum compressive strength is 68.36 MPa for 28 days resulted from mixture using 100% fly ash and Na2SiO3 and NaOH with ratio 2.75. The largest value of slump flow test resulted from mixture using Na2SiO3 and NaOH with ratio 2.50 is 17.25 cm. Based on SEM test results, mortar geopolymer microstructure with mixture RHA 0% has less pores and denser CSH structure.

  14. Comparative Study between Direct and Pseudomorphic Transformation of Rice Husk Ash into MFI-Type Zeolite.

    Science.gov (United States)

    Alyosef, Hallah Ahmad; Roggendorf, Hans; Schneider, Denise; Inayat, Alexandra; Welscher, Julia; Schwieger, Wilhelm; Münster, Tom; Kloess, Gert; Ibrahim, Suzan; Enke, Dirk

    2017-12-21

    Pre-shaped mesoporous amorphous rice husk ash (RHA) and MCM-41 derived from RHA as a silica source were transformed into MFI-type zeolites using two different structure-directing agents. Tetrapropylammonium hydroxide (TPAOH) was utilized as an alkali source for silica dissolution and structure control during the direct transformation of RHA into zeolite. A monopropylamine (PA)-containing alkaline solution (NaOH) was used for the pseudomorphic transformation of RHA or MCM-41 into zeolite. The hydrothermal conversion of RHA or MCM-41 into MFI-type zeolites was investigated as a function of reaction time at 175 °C. With PA as template, the crystallization took place inside and on the outer surface of RHA or MCM-41 without losing the original shape of the initial silica sources, while TPAOH led to the formation of conventional MFI-type zeolite crystals due to the complete dissolution of RHA. The final products were characterized by X-ray diffraction, nitrogen adsorption, scanning electron microscopy, and optical emission spectroscopy.

  15. Effect of black rice husk ash on the physical and rheological properties of bitumen

    Science.gov (United States)

    Romastarika, Raissa; Jaya, Ramadhansyah Putra; Yaacob, Haryati; Nazri, Fadzli Mohamed; Agussabti, Ichwana, Jayanti, Dewi Sri

    2017-08-01

    Black rice husk ash (BRHA) waste product is inexpensive and can be obtained from rice mills. Reuse of waste product is ideal to reduce pollution, because disposal is decreased or eliminated. The commercial value of BRHA has increased, and it is suitable for use in road construction. In this study, BRHA waste was ground using a grinding ball mill for 120 min to form fine powder. BRHA was then sieved to less than 75 µm. At the laboratory, BRHA was mixed with bitumen to replace 2%, 4%, and 6% of the total weight, whereas 0% represented the control sample. The penetration, softening point, dynamic shear rheometer (DSR) and rolling thin film oven (RTFO) were investigated in this study. Results showed that bitumen became harder, whereas the rate of penetration decreased when the replacement amount of BRHA increased. Softening point test of bitumen also revealed an increase. The short-term aging test revealed that modification of bitumen could relieve the effect of aging. BRHA waste added into bitumen improved the performance of bitumen. Therefore, the usage of BRHA could help improve the performance of road pavement and reduce the rutting effect.

  16. Investigation of silica from rice husk ash wastes as an alternative material for microwave absorbers

    Science.gov (United States)

    Sudiana, I. Nyoman; Mitsudo, Seitaro; Firihu, Muhammad Zamrun; Aba, La; Ngkoimani, La Ode; Arsana, Made Widana; Aripin, Haji

    2017-01-01

    An attempt was made to produce silica from an agricultural waste, i.e. rice husk ash (RHA), for a microwave absorber. The high percentage of silica content from RHA was used as a silica source for sodium silica solutions. Different heating temperatures, times and acid treatments were studied for silica extractions. The composite was characterized and its microwave properties were investigated after sintering from 400 to 1200 °C. The results showed that the existing phases in all compositions at 1200 °C were mullite, cristobalite and Al2O3. The intensities of cristobalite peaks gradually decreased with increased compositions of Al2O3, while the intensities of mullite peaks increased with the increased compositions of Al2O3. Compositions with higher amounts of amorphous silica xerogel showed a lower degree of Al2O3 peaks when compared to other compositions, while the peaks of cristobalite were found to be with greater intensities. A correlation between the structural changes and the microwave properties of the samples in frequencies ranging from 8.2 to 12.4 GHz has been found and discussed. The calculated values showed that the reflection losses decreased as t he sintering temperatures were increased up to 1200 °C. The increasing degree of crystallinity was identified as the main reason for the decrease of the reflection losses since the silica xerogel glass ceramic becomes more transparent to microwaves.

  17. Kinetic study of brilliant green adsorption from aqueous solution onto white rice husk ash.

    Science.gov (United States)

    Tavlieva, Mariana P; Genieva, Svetlana D; Georgieva, Velyana G; Vlaev, Lyubomir T

    2013-11-01

    The present research was focused on the study of adsorption kinetics of brilliant green (BG) onto white rice husk ash from aqueous solutions. The research was performed in the temperature interval 290-320 K in 10° steps and in the concentration range of 3-100 mg L(-1). Batch studies were conducted in order to determine the optimal adsorbent dose, and the time required to reach the adsorption equilibrium at each temperature. The effect of the initial concentration of brilliant green was studied (pH not adjusted), as well as the effect of temperature. The maximum adsorption capacity of the WRHA for BG at 320 K was determined to be 85.56 mg g(-1). The adsorption kinetic data were analyzed employing several kinetic models: pseudo-first-order equation, pseudo-second-order equation, Elovichequation, Banghman's equation, Diffusion-chemisorption model, and Boyd kinetic expression. It was established that the adsorption process obeyed the pseudo-second-order kinetic model. Based on the rate constants obtained by this kinetic model using Arrhenius and Eyring equations, the activation parameters were determined, namely the activation energy (50.04 kJ mol(-1)), the change of entropy (-318.31 J mol(-1) K(-1)), enthalpy (-47.50 kJ mol(-1)), and Gibbs free energy (range 44.81-54.36 kJ mol(-1)) for the formation of activated complex from the reagents. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Adsorption of sulfur compound utilizing rice husk ash modified with niobium

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcanti, Rodrigo M.; Pessoa Júnior, Wanison A.G. [Laboratório de Catálise Química e Materiais (CATAMA), Instituto de Ciências Exatas, Universidade Federal do Amazonas (UFAM), Av. Gen. Rodrigo Otávio Jordão Ramos, 6200, 69077-000 Manaus, AM (Brazil); Braga, Valdeilson S. [Laboratório de Catálise, Centro das Ciências Exatas e das Tecnologias, Universidade Federal do Oeste da Bahia, Rua Professor José Seabra de Lemos, 316, Recanto dos Pássaros, 47808-021 Barreira, BA (Brazil); Barros, Ivoneide de C.L., E-mail: iclbarros@gmail.com [Laboratório de Catálise Química e Materiais (CATAMA), Instituto de Ciências Exatas, Universidade Federal do Amazonas (UFAM), Av. Gen. Rodrigo Otávio Jordão Ramos, 6200, 69077-000 Manaus, AM (Brazil)

    2015-11-15

    Graphical abstract: - Highlights: • Adsorbents based in RHA modified with niobium were prepared by impregnation. • The impregnation modified the particle size and topology of RHA particles. • The adsorbents were applied in sulfur removal in model liquid fuels. • The larger sulfur removal (>50%) was achieved using RHA with 5 wt.% niobium oxide. • The adsorbent show great selectivity in adsorption experiments. - Abstract: Adsorbents based in rice husk ash (RHA) modified with niobium pentoxide were prepared for impregnation methods and applied in sulfur removal in liquid fuels. The solids were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, nitrogen physisorption and thermal analysis; they show that there was no qualitative change in the amorphous structure of the RHA; however, the method of impregnation could modify the particle size and topology of RHA particles. The larger sulfur removal (>50%) was achieved using RHA with 5 wt.% Nb{sub 2}O{sub 5} at a dosage of 10 g L{sup −1}, after 4 h of contact with the model fuel. The kinetic study of adsorption of thiophene showed that the models of pseudo-second order and intra-particle diffusion best fit the experimental data. The adsorption experiments with the thiophenic derivatives compounds show a large selectivity of the adsorbent.

  19. Modeling and Optimization of Compressive Strength of Hollow Sandcrete Block with Rice Husk Ash Admixture

    Directory of Open Access Journals (Sweden)

    2016-11-01

    Full Text Available The paper presents the report of an investigation into the model development and optimization of the compressive strength of 55/45 to 70/30 cement/Rice Husk Ash (RHA in hollow sandcrete block. The low cost and local availability potential of RHA, a pozzolanic material gasps for exploitation. The study applies the Scheffe\\'s optimization approach to obtain a mathematical model of the form f(xi1 ,xi2 ,xi3 xi4 , where x are proportions of the concrete components, viz: cement, RHA, sand and water. Scheffe\\'s i experimental design techniques are followed to mould various hollow block samples measuring 450mm x 225mm x 150mm and tested for 28 days strength. The task involved experimentation and design, applying the second order polynomial characterization process of the simplex lattice method. The model adequacy is checked using the control factors. Finally, a software is prepared to handle the design computation process to take the desired property of the mix, and generate the optimal mix ratios. Reversibly, any mix ratios can be desired and the attainable strength obtained.

  20. Rice husk ash as an effective adsorbent: evaluation of adsorptive characteristics for Indigo Carmine dye.

    Science.gov (United States)

    Lakshmi, Uma R; Srivastava, Vimal Chandra; Mall, Indra Deo; Lataye, Dilip H

    2009-02-01

    Present study explored the adsorptive characteristics of Indigo Carmine (IC) dye from aqueous solution onto rice husk ash (RHA). Batch experiments were carried out to determine the influence of parameters like initial pH (pH(0)), contact time (t), adsorbent dose (m) and initial concentration (C(0)) on the removal of IC. The optimum conditions were found to be: pH(0)=5.4, t=8h and m=10.0 g/l. The pseudo-second-order kinetic model represented the adsorption kinetics of IC on to RHA. Equilibrium isotherms were analyzed by Freundlich, Langmuir, Temkin and Redlich-Peterson models using a non-linear regression technique. Adsorption of IC on RHA was favorably influenced by an increase in the temperature of the operation. The positive values of the change in entropy (DeltaS(0)) and heat of adsorption (DeltaH(0)); and the negative value of change in Gibbs free energy (DeltaG(0)) indicate feasible and spontaneous adsorption of IC on to RHA.

  1. Synthesis of adsorbent with zeolite structure from red mud and rice husk ash and its properties

    Science.gov (United States)

    Quyen, Dinh Thi Ngoc; Loc, Luu Cam; Ha, Huynh Ky Phuong; Nga, Dang Thi Hang; Tri, Nguyen; Van, Nguyen Thi Thuy

    2017-09-01

    There are many researches in the modification of red mud as adsorbent for treatment of wastewater or waste gases. Yet, most of them have to face up with a thorny problem caused by remaining alkali in red mud. In this study, the material with zeolite structure was synthesized by fusion method using red mud with the remaining alkali and rice husk ash as raw materials. It comprised alkaline fusion followed by hydrothermal treatment with step - change of synthesis temperature. The synthesized materials were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), BET and CO2 adsorption capacity. The influences on the quality of these materialswere investigated under various calcination temperatures, calcination times and the ratios of raw materials (based on SiO2/Al2O3 ratio). The optimum reaction parameters were determined. The results depicted that the sample treated at 600 °C for 2 hours with the ratio of SiO2/Al2O3 of 1.8 had the best adsorption capacity and total specific surface area compared with the others.

  2. Correlation between Compressive Strength and Fire Resistant Performance of Rice Husk Ash-Based Geopolymer Binder for Panel Applications

    Directory of Open Access Journals (Sweden)

    Mohd Basri Mohd Salahuddin

    2017-01-01

    Full Text Available Panel structures which are mainly used as insulation materials should possess high fire resistance characteristic. In addition, their mechanical requisites for walls and doors such as compressive strength must not be unduly compromised. Rice husk ash (RHA was used as an aluminosilicate source and two factors namely RHA/AA ratio and NaOH concentration were analyzed using statistical tool to study the effect of both factors on the compressive strength. Surface morphology and fire resistant behavior of four selected samples based on their compressive strength (brittle, semi-brittle, ductile, and semi-ductile samples were studied to determine the correlation between compressive strength and fire resistant performance of those selected samples. Results showed that RHA-based geopolymer sample recorded high compressive strength above 28 MPa when its RHA/AA ratio and NaOH concentration were high ranging from 0.7 to 0.8 and 12M to 14M, respectively. Brittle geopolymer sample (GS with low Si/Al ratio shows high compressive strength together with high degree of geopolymerization. Ductile GS in comparison, shows low compressive strength irrespective of its degree of geopolymerization. Semi-ductile GS showed the best fire resistant properties with a maximum non-exposed surface temperature of only 50°C after 50 minutes (after it was exposed to a direct fire with temperature of 900°C followed by semi-brittle and brittle GS.

  3. ABSORPTION AND PERMEABILITY PERFORMANCE OF SELANGOR RICE HUSK ASH BLENDED GRADE 30 CONCRETE

    Directory of Open Access Journals (Sweden)

    KARTINI, K.

    2010-03-01

    Full Text Available Substituting waste materials in construction is well known for conservation of dwindling resources and preventing environmental and ecological damages caused by quarrying and depletion of raw materials. Many researches had shown that some of these wastes have good pozzolanic properties that would improve the quality of concrete produced. One such waste material is agricultural waste rice husk, which constitute about one-fifth of 600 million tonnes of rice produced annually in the world. The RHA obtained by burning the rice husk in the ferrocement furnace and used as a cement replacement material. The use of this supplementary cementing material is expected to meet the increase in demand of cement, as the current world cement production of approximately 1.2 million tonnes is expected to grow exponentially to about 3.5 billions tonnes per year by 2015. This paper reports the results of durability performance conducted on the normal strength concrete specimens of 30 N/mm2 containing 20% or 30% RHA by cement weight, with or without addition of superplasticizer. The results show that replacement of cement with RHA lowers initial surface absorption, lowers the permeability, lowers the absorption characteristics, longer time taken for the capillary suction resulted in lower sorptivity value, lower water permeability and increase the resistance of concrete to chloride ion penetration in comparison with the OPC control concrete. The present investigations revealed that incorporation RHA significantly improve the absorption and permeability characteristics of concrete.

  4. Synthesis of zeolite from rice husk ash waste of brick industries as hydrophobic adsorbent for fuel grade ethanol purification

    Science.gov (United States)

    Purnomo, A.; Alhanif, M.; Khotimah, C.; Zuhra, UA; Putri, BR; Kumoro, AC

    2017-11-01

    A lot of researchers have devoted on ethanol utilization as renewable energy to substitute petroleum based gasoline. When ethanol is being used as a new fuel candidate, it should have at least of 99.5% purity. Usually produced via sugar fermentation process, further purification of ethanol from other components in fermentation broth to obtain its fuel grade is a crucial step. The purpose of this research is to produce synthetic zeolite as hydrophobic adsorbent from rice husk ash for ethanol-water separation and to investigate the influence of weight, adsorption time and initial ethanol concentration on zeolite adsorption capacity. This research consisted of rice husk silica extraction, preparation of hydrophobic zeolite adsorbent, physical characterization using SEM, EDX and adsorption test for an ethanol-water solution. Zeolite with highest adsorption capacity was obtained with 15: 1 alumina silica composition. The best adsorption condition was achieved when 4-gram hydrophobic zeolite applied for adsorption of 100 mL of 10% (v/v) ethanol-water solution for 120 minutes, which resulted in ethanol with 98.93% (v/v) purity. The hydrophobic zeolite from rice husk ash is a potential candidate as an efficient adsorbent to purify raw ethanol into fuel grade ethanol. Implementation of this new adsorbent for ethanol production in commercial scale may reduce the energy consumption of that usually used for the distillation processes.

  5. Rice husk ash as a source of silica in alkali-activated fly ash and granulated blast furnace slag systems

    Directory of Open Access Journals (Sweden)

    Mejía, J. M.

    2013-09-01

    Full Text Available This study assesses the viability of using an agro-industrial by-product, rice husk ash (RHA from a Colombian rice company’s combustion facility, as a total replacement for the commercial sodium silicate ordinarily used in alkaliactivated binders. Fly ash (FA, granulated blast furnace slag (GBFS and binary 50FA:50GBFS blended pastes were activated with a mix of sodium hydroxide and either sodium silicate or one of two types of RHA. The pastes were characterised for strength, mineralogy and microstructure. The findings showed that the agro-industrial by-product can be used to yield alkali-activated materials with 7-day mechanical strengths on the order of 42 MPa. The study confirmed that both amorphous silica and part of the crystalline silica present in RHA participate in the alkaline activation process, providing the alkalinity is suitably adjusted.Este estudio evalúa la viabilidad de utilizar un subproducto agroindustrial, la ceniza de cascarilla de arroz (RHA proveniente de un equipo combustor de una empresa Arrocera en Colombia, como reemplazo total de la sílice aportada por el silicato de sodio comercial en sistemas cementicios activados alcalinamente. Se prepararon pastas de ceniza volante (FA, de escoria de alto horno (GBFS y un sistema binario 50FA:50GBFS, que fueron activadas por una mezcla de silicato de sodio e hidróxido de sodio, y por dos tipos de RHA. Las mezclas se caracterizaron mecánica, mineralógica y microestructuralmente. Los resultados demuestran que es posible obtener materiales activados alcalinamente con resistencias mecánicas del orden de 42 MPa, a 7 días de curado, utilizando el subproducto agroindustrial. Este estudio corrobora que tanto la sílice amorfa como parte de la sílice cristalina presente en RHA tienen la posibilidad de participar en el proceso de activación alcalina, siempre y cuando las condiciones de alcalinidad estén adecuadamente ajustadas.

  6. Rice Husk Ash as a Renewable Source for the Production of Value Added Silica Gel and its Application: An Overview

    Directory of Open Access Journals (Sweden)

    Ram Prasad

    2012-06-01

    Full Text Available In recent years, silica gels have developed a lot of interest due to their extraordinary properties and their existing and potential applications in science and technology. Silica gel has a wide range of applications such as a desiccant, as a preservation tool to control humidity, as an adsorbent, as a catalyst and as a cata-lyst support. Silica gel is a rigid three-dimensional network of colloidal silica, and is classified as: aqua-gel, alco-gel, xero-gel and aero-gel. Out of all known solid porous materials, aero-gels are particularly known for their high specific surface area, high porosity, low bulk density, high thermal insulation value, ultra low dielectric constant and low index of refraction. Because of these extraordinary properties silica aero-gel has many commercial applications such as thermal window insulation, acoustic barriers, super-capacitors and catalytic supports. However, monolithic silica aero-gel has been used extensively in high energy physics in Cherenkov radiation detectors and in shock wave studies at high pressures, inertial confinement fusion (ICF radio-luminescent and micrometeorites. Silica gel can be prepared by using various sol gel precursors but the rice husk (RH is considered as the cheapest source for silica gel production. Rice husk is a waste product abundantly available in rice producing countries during milling of rice. This review article aims at summarizing the developments carried out so far in synthesis, properties, characterization and method of determination of silica, silica gel, silica aero-gel and silica xero-gel. The effect of synthesis parameters such as pH, temperature of burning the rice husk, acid leaching prior to formation of rice husk ash (RHA on the properties of final product are also described. The attention is also paid on the application of RH, RHA, sil-ica, silica aero-gel and silica xero-gel. Development of economically viable processes for getting rice husk silica with specific

  7. Extraction of Pb2+ using Silica from Rice Husks Ash (RHA – Chitosan as Solid Phase

    Directory of Open Access Journals (Sweden)

    Hanandayu Widwiastuti

    2013-03-01

    Full Text Available The existence of lead (Pb compounds in waters can be caused of waste pollution from industrial activities such as dye and battery industries. Lead has toxic characteristic and is able to causing deseases. The levels of Cr(VI can be decreased by methods such as electroplating, oxidation, reduction, and membrane separation. But this methods require high cost and produce a lot of waste. Furthermore, those methods cannot determine the small concentration of Pb2+. Therefore, solid phase extraction is used because it’s a simple method and can be used to preconcentrate Pb2+ ion. The aim of this study is to create solid phase from nature material as an alternative method to determine Pb2+ in water samples. The solid phase is silica from rice husks ash (RHA that was modified using chitosan. To achieve that aim, the optimization of silica : chitosan composition was done. The influence of Pb2+ concentration and citric acid concentration was studied to obtain optimum recovery of Pb2+. Interaction between Pb2+ ion and solid phase silica – chitosan could be estimated based on the result. The result showed the optimum composition of silica : chitosan is 65% silica : 35% chitosan with Cation Exchange Capacity (CEC 0.00455 mek/g. Mass Adsorbed Pb2+for 1 g silica : chitosan 65% is 9.715 mg/g. Optimum recovery of Pb2+ on solid phase extraction is reached at concentration of Pb2+ 10 ppm and citric acid concentration 0.05 M (88.25 % and 81.18 %. This result showed that solid phase extraction using silica – chitosan can be used as an alternative method to determine Pb2+ in water.

  8. Rice Husk Ash to Stabilize Heavy Metals Contained in Municipal Solid Waste Incineration Fly Ash: First Results by Applying New Pre-treatment Technology.

    Science.gov (United States)

    Benassi, Laura; Franchi, Federica; Catina, Daniele; Cioffi, Flavio; Rodella, Nicola; Borgese, Laura; Pasquali, Michela; Depero, Laura E; Bontempi, Elza

    2015-10-09

    A new technology was recently developed for municipal solid waste incineration (MSWI) fly ash stabilization, based on the employment of all waste and byproduct materials. In particular, the proposed method is based on the use of amorphous silica contained in rice husk ash (RHA), an agricultural byproduct material (COSMOS-RICE project). The obtained final inert can be applied in several applications to produce "green composites". In this work, for the first time, a process for pre-treatment of rice husk, before its use in the stabilization of heavy metals, based on the employment of Instant Pressure Drop technology (DIC) was tested. The aim of this work is to verify the influence of the pre-treatment on the efficiency on heavy metals stabilization in the COSMOS-RICE technology. DIC technique is based on a thermomechanical effect induced by an abrupt transition from high steam pressure to a vacuum, to produce changes in the material. Two different DIC pre-treatments were selected and thermal annealing at different temperatures were performed on rice husk. The resulting RHAs were employed to obtain COSMOS-RICE samples, and the stabilization procedure was tested on the MSWI fly ash. In the frame of this work, some thermal treatments were also realized in O2-limiting conditions, to test the effect of charcoal obtained from RHA on the stabilization procedure. The results of this work show that the application of DIC technology into existing treatment cycles of some waste materials should be investigated in more details to offer the possibility to stabilize and reuse waste.

  9. Rice Husk Ash to Stabilize Heavy Metals Contained in Municipal Solid Waste Incineration Fly Ash: First Results by Applying New Pre-treatment Technology

    Directory of Open Access Journals (Sweden)

    Laura Benassi

    2015-10-01

    Full Text Available A new technology was recently developed for municipal solid waste incineration (MSWI fly ash stabilization, based on the employment of all waste and byproduct materials. In particular, the proposed method is based on the use of amorphous silica contained in rice husk ash (RHA, an agricultural byproduct material (COSMOS-RICE project. The obtained final inert can be applied in several applications to produce “green composites”. In this work, for the first time, a process for pre-treatment of rice husk, before its use in the stabilization of heavy metals, based on the employment of Instant Pressure Drop technology (DIC was tested. The aim of this work is to verify the influence of the pre-treatment on the efficiency on heavy metals stabilization in the COSMOS-RICE technology. DIC technique is based on a thermomechanical effect induced by an abrupt transition from high steam pressure to a vacuum, to produce changes in the material. Two different DIC pre-treatments were selected and thermal annealing at different temperatures were performed on rice husk. The resulting RHAs were employed to obtain COSMOS-RICE samples, and the stabilization procedure was tested on the MSWI fly ash. In the frame of this work, some thermal treatments were also realized in O2-limiting conditions, to test the effect of charcoal obtained from RHA on the stabilization procedure. The results of this work show that the application of DIC technology into existing treatment cycles of some waste materials should be investigated in more details to offer the possibility to stabilize and reuse waste.

  10. Phytoremediation of Gold Mine Tailings Amended with Iron-Coated and Uncoated Rice Husk Ash by Vetiver Grass (Vetiveria zizanioides (Linn.) Nash)

    OpenAIRE

    Tariq, F. S.; Samsuri, A. W.; Karam, D. S.; A. Z. Aris

    2016-01-01

    This study was undertaken to determine the effects of rice husk ash (RHA) and iron-coated rice husk ash (Fe-RHA) on phytoavailability of As, Cd, Cr, Cu, Mn, Pb, and Zn to vetiver grass grown in gold mine tailings amended with either RHA or Fe-RHA at 0%, 5%, 10%, and 20% (w/w). The results showed that the RHA amended tailings recorded higher concentration of As in the shoot and the root and higher concentration of Cr and Mn in the root compared to the untreated tailings which was used as a con...

  11. SYNTHESIS OF ZEOLITE SOCONY MOBIL FROM BLUE SILICA GEL AND RICE HUSK ASH AS CATALYSTS FOR HYDROTHERMAL LIQUEFACTION

    Directory of Open Access Journals (Sweden)

    SUYITNO

    2015-08-01

    Full Text Available Renewable biofuels produced by the hydrothermal liquefaction of rice husks have received much attention because of rapid increases in fuel consumption and corresponding declines in fossil fuel resources. To increase biofuel yields, template-free syntheses of Zeolite Socony Mobil (ZSM catalysts based on blue silica gel and rice husk ash as silica sources were studied. After ZSM synthesis in a closed reactor at 170°C, the crystallinity and crystalline diameters of the products were determined by X-ray diffraction, affording values of 56.33%– 65.81% and 64.3–68.5 nm, respectively. The hydrothermal liquefaction of rice husks with or without a catalyst was conducted in a closed reactor (1200 mm length × 100 mm diameter at 275°C for 45 min. The light biofuel was separated from the ethanol solvent and heavy biofuel via vacuum evaporation. The ZSM catalysts increased the biofuel yields by 2.9%–6.0%. The light biofuels exhibited heating values, flash points, and viscosities of approximately 4.2–4.3 kcal·g−1, 19°C, and 1.48–1.52 cSt, respectively. However, further studies are required to enhance the activity of the ZSMs and increase the quality of the biofuels.

  12. Comparison on the Surface Structure Properties along with Fe(II) and Mn(II) Removal Characteristics of Rice Husk Ash, Inactive Saccharomyces cerevisiae Powder, and Rice Husk.

    Science.gov (United States)

    Jiang, Zhao; Cao, Bo; Su, Guangxia; Lu, Yan; Zhao, Jiaying; Shan, Dexin; Zhang, Xiuyuan; Wang, Ziyi; Zhang, Ying

    2016-01-01

    This study selected solid wastes, such as rice husk ash (RHA), inactive Saccharomyces cerevisiae powder (ISP), and rice husk (RH), as the potential adsorbents for the removal of Fe(II) and Mn(II) in aqueous solution. The structural characteristics, functional groups, and elemental compositions were determined by scanning electron microscope (SEM) and Fourier translation infrared spectrum (FT-IR) analyses, respectively. Then the influence on the Fe(II) and Mn(II) removing efficiency by the factors, such as pH, adsorbent dosage, initial Fe(II) and Mn(II) concentration, and contact time, was investigated by the static batch test. The adsorption isotherm study results show that Langmuir equation can better fit the Fe(II) and Mn(II) adsorption process by the three adsorbents. The maximum adsorption amounts for Fe(II) were 6.211 mg/g, 4.464 mg/g, and 4.049 mg/g by RHA, ISP, and RH and for Mn(II) were 3.016 mg/g, 2.229 mg/g, and 1.889 mg/g, respectively. The adsorption kinetics results show that the pseudo-second-order kinetic model can better fit the Fe(II) and Mn(II) adsorption process. D-R model and thermodynamic parameters hint that the adsorption processes of Fe(II) and Mn(II) on the three adsorbents took place physically and the processes were feasible, spontaneous, and exothermic.

  13. Studies on the Effect of Rice Husk Ash as Cement Admixture * M.U ...

    African Journals Online (AJOL)

    acer

    compact whole (Neville, 1996). Cements are classified as calcium silicate and calcium aluminate cement. Calcium silicate cement is further classified into Portland and Slag, while calcium aluminate is classified into High alumina and Pozzolona cement (Jackson and Dhir, 1991). Rice husk has recently been recognized as.

  14. Effects of rice husk ash and termite hill types on the physical and ...

    African Journals Online (AJOL)

    Clay bricks remain the most widely used materials in the building and construction industries, due to their good qualities, low cost and versatility compared to other materials for building purposes. More so, the large quantities of agricultural waste produced, such as rice husk resulting from high consumption of rice worldwide ...

  15. effects of variability in the pozzolanic properties of rice husk ash

    African Journals Online (AJOL)

    user

    “Effect of Grinding on Chemical and Physical. Properties of Rice Husk Ash”. International Journal of. Minerals, Metallurgy and Materials, Vol. 16, Number 2,. Pp 242, 2009. [11] Ajay Kumar,Kalyani Mohanta, Devendra Kumar and Om. Parkash. “Properties and Industrial Applications of Rice husk”. International Journal of ...

  16. Influence of Plastic Waste Fibers on the Strength of Lime-Rice Husk Ash Stabilized Clay Soil

    Directory of Open Access Journals (Sweden)

    A. S. Muntohar

    2009-01-01

    Full Text Available A study has been undertaken to investigate the strength of stabilized clay-soil reinforced with randomly distributed discrete plastic waste fibers by carrying out unconfined compressive strength and tensile-split strength test. In this study, the clay soil was stabilized with lime and rice husk ash mixtures. The effect of the fiber length and content on the compressive and split tensile strength was investigated. The laboratory investigation results show that inclusion of the plastic waste fiber increased significantly both the unconfined compressive strength and tensile-split strength of the stabilized clay soil. The fiber length plays a significant contribution in increasing the soil strength. To contribute for any significant improvement on compression as well as tensile strength, the fiber length should be in range of 20 mm to 40 mm. Fiber reinforcements also reduced soil brittleness by providing smaller loss of post-peak strength.

  17. Pengaruh Pemberian Abu Sekam Padi Sebagai Bahan Desikan Pada Penyimpanan Benih Terhadap Daya Tumbuh Dan Pertumbuhan Bibit Kakao (the Effects of Rice Husk Ash as Desiccation Material of Seed Storage on Viability and Cocoa Seedling Growth).

    OpenAIRE

    Rahardjo, Pudji

    2012-01-01

    Rice husk ash as desiccation material can be used to maintain seed viability in storage through its ability to absorb humidity during its storage. High relative humidity caused seed moisture content to increase so the respiration rate of seed increases and uses faster food stock. Finally the viability of seed is lost. A research on use of rice husk ash as desiccation material of cocoa seed storage was conducted in Agronomy Laboratory and Kaliwining Experimental Station, Indonesian Coffee and ...

  18. The Utilization of Bottom Ash Coal for Briquette Products by Adding Teak Leaves Charcoal, Coconut Shell Charcoal, and Rice Husk Charcoal

    Directory of Open Access Journals (Sweden)

    Syafrudin Syafrudin

    2015-01-01

    Full Text Available The limitations of the availability of energy sources especially fuel oil has become a serious threat for the society. The use of coal for energy source as the replacement of fuel oil, in one hand, is very profitable, but on the other hand, will cause problem which is the coal ash residue. This coal ash is a by-product of coal combustion. This coal ash contains bottom ash. Through this observation, the bottom ash can be processed to be charcoal if added by teak leaves, coconut shell, and rice husk. Also, this observation needs to add binder materials for further processing in order to form briquette. It can be used as alternative fuel, the utilization of bottom ash and biomass will give positive impact to the environment. This observation was conducted by using compositions such as bottom ash, teak leaves, coconut shell, and rice husk. The treatment was using comparison 100%:0% ; 80%:20% ; 60%:40% ; 50%:50% ; 40%:60% ; 20%:80% ; 0%:100%. The result that the best briquette was on the composition of 20% bottom ash : 80% coconut shell. The characteristic values from that composition were moisture content of 3.45%, ash content of 17,32%, calorific value of 7.945,72 Cal/gr, compressive strength of 2,18 kg/cm2, level of CO of 105 mg/m3, and heavy metals Cu of 29,83 µg/g and  Zn 32,99 µg/g. The characteristic value from each briquette composition treatment showed that the increasing usage proportion of biomass as added material for briquette was able to increase its moisture content and calorific value. Besides, it is also able to decrease its ash content and compressive strength

  19. Caracterização de cinza obtida por combustão de casca de arroz em reator de leito fluidizado Characterization of ash from combustion of rice husk in a fluidized bed reactor

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    Juan Daniel Martínez Angel

    2009-01-01

    Full Text Available The rice husk combustion in a bubbling and atmospheric fluidized bed reactor was investigated. This paper presents the rice husk ash characterization employing the techniques of X-ray diffraction (XRD, X-ray fluorescence (XRF, and scanning electron microscopy (SEM among others. After combustion, a rice husk ash containing 93% amorphous silica and <3% unburned char was produced. Methods usually applied to fixed bed considering external sources of energy and high reaction times were employed. Thus, the potential of this type of reactors with respect to speed, continuity and self-sufficiency energy of the process was shown.

  20. Effect of Rice Husk Ash Insulation Powder on the Reoxidation Behavior of Molten Steel in Continuous Casting Tundish

    Science.gov (United States)

    Kim, Tae Sung; Chung, Yongsug; Holappa, Lauri; Park, Joo Hyun

    2017-06-01

    Rice husk ash (RHA) has been widely used as an insulation powder in steel casting tundish. Its effect on the reoxidation of molten steel in tundish as well as on the corrosion of magnesia refractory was investigated. The reoxidation of the steel, indicated by an oxygen pickup, was progressed by increasing the ratio of RHA to the sum of RHA and carryover ladle slag ( R ratio) greater than about 0.2. The increase of the silica activity in the slag layer promoted the self-dissociation of SiO2 from the slag layer into the molten steel, resulting in the silicon and oxygen pickup as the R ratio increased. The total number of reoxidation inclusions dramatically increased and the relative fraction of Al2O3-rich inclusions increased by increasing the R ratio. Hence, the reoxidation of molten steel in tundish might become more serious due to the formation of alumina-rich inclusions as the casting sequence increases. MgO in the refractory directly dissolved into the molten slag layer without forming any intermediate compound layer ( e.g., spinel), which is a completely different situation from the general slag-refractory interfacial reaction. A flow was possibly induced by the bursting of gas bubbles at the ash-slag (-refractory) interface, since the silica in the RHA powder continuously dissolved into the molten slag pool. Thus, the RHA insulation powder has a negative effect on the corrosion of MgO refractory.

  1. Lightweight Heat Resistant Geopolymer-based Materials Synthesized from Red Mud and Rice Husk Ash Using Sodium Silicate Solution as Alkaline Activator

    Directory of Open Access Journals (Sweden)

    Hoc Thang Nguyen

    2017-01-01

    Full Text Available Geopolymer is an inorganic polymer composite with potentials to replace Ordinary Portland Cement (OPC-based materials in the future because of its lower energy consumption, minimal CO2 emissions and lower production cost as it utilizes industrial waste resources. Hence, geopolymerization and the process to produce geopolymers for various applications like building materials can be considered as green industry. Moreover, in our study, the raw materials we used are red mud and rice husk ash, which are are industrial and agricultural wastes that need to be managed to reduce their impact to the environment. The red mud and rice husk ash combined with sodium silicate (water glass solution were mixed to form geopolymer materials. Moreover, the geopolymer specimens were also tested for heat resistance at a temperature of 1000°C for 2 hours. Results suggest high heat resistance with an increase of compressive strength after exposed at high temperature.

  2. Evaluation of nitric and acetic acid resistance of cement mortars containing high-volume black rice husk ash.

    Science.gov (United States)

    Chatveera, B; Lertwattanaruk, P

    2014-01-15

    This paper presents the performance of cement mortar containing black rice husk ash (BRHA) under nitric and acetic acid attacks. The BRHA, collected from an electrical generating power plant that uses rice husk as fuel, was ground using a grinding machine. The compressive strength loss, weight loss, and expansion of mortars under nitric and acetic acid attack were investigated. The test results of BRHA properties in accordance with the ASTM C 618 standard found that the optimal grinding time was 4 h as this achieved a Blaine fineness of 5370 cm(2)/g. For parametric study, BRHA were used as a Portland cement Type 1 replacement at the levels of 0%, 10%, 20%, 30%, 40%, and 50% by weight of binder. The water-to-binder ratios were 0.55, 0.60, and 0.65. From test results, when the percentage replacements of BRHA in cement increased, it was observed that the strength loss and weight loss of mortars containing BRHA under acetic acid attack were higher than those of the mortars against nitric acid attack. It was found that, of the various BHRA mortars, the strength loss and weight loss due to nitric and acetic acid attacks were the lowest in the mortar with 10% BRHA replacement. For 10%, 20% and 30% BRHA replacements, the rate of expansion of the BRHA mortar decreased when compared with the control mortar. For the mortars with other percentage replacements of BRHA, the rate of expansion increased. Furthermore, the effective water-to-binder ratios of control and BRHA mortars were the primary factor for determining the durability of mortar mixed with BRHA. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. The Characteristic and Activation of Mixed Andisol Soil/Bayat Clays/Rice Husk Ash as Adsorbent of Heavy Metal Chromium (Cr)

    Science.gov (United States)

    Pranoto; Sajidan; Suprapto, A.

    2017-02-01

    Chromium (Cr) concentration in water can be reduced by adsorption. This study aimed to determine the effect of Andisol soil composition/Bayat clay/husk ash, activation temperature and contact time of the adsorption capacity of Cr in the model solution; the optimum adsorption conditions and the effectiveness of ceramic filters and purifiers to reduce contaminant of Cr in the water. The mixture of Andisol soil, Bayat clay, and husk ash is used as adsorbent of metal ion of Cr(III) using batch method. The identification and characterisation of adsorbent was done with NaF test, infrared spectroscopy (FTIR), X-ray diffraction (XRD). Cr metal concentrations were analyzed by atomic absorption spectroscopy. Sorption isotherms determined by Freundlich equation and Langmuir. The optimum conditions of sorption were achieved at 150°C activation temperature, contact time of 30 minutes and a composition Andisol soil / Bayat clay / husk ash by comparison 80/10/10. The results show a ceramic filter effectively reduces total dissolved solids (TDS) and Chromium in the water with the percentage decrease respectively by 75.91% and 9.44%.

  4. Effect of particle size and addition of cocoa pod husk on the properties of sawdust and coal pellets

    Directory of Open Access Journals (Sweden)

    C. A. Forero Nuñez

    2016-02-01

    Full Text Available The continuous increase of the world energy demand, the rise of fossil fuels costs, and the strong environmental policies around the globe are some of the reasons for the wood pellets industry increase. However, there are some other available biomass feedstocks capable of being densified for energy production. Among the various options, the use of mixed biomass pellets is becoming remarkable due to the wide variety of species, although more research is needed in order to enhance the mechanical properties of these pellets. This study aims to identify the effect of particle size on the mechanical properties of sawdust and coal pellets when cocoa pod husks are used as an additive. Cocoa pod husks have a similar composition to sawdust and less sulfur and nitrogen than coal. Thus, the use of this additive might decrease the environmental impact during coal pellets combustion. Results show an attractive potential of cocoa pod husks grinds for pellet production, an increase of the durability of coal pellets mixed with this raw material, and similar performance between cocoa pod husks and sawdust pellets. The compression ratio, the compressive and impact resistance varied linearly with the addition of cocoa pod husks.

  5. Review of the rice production cycle: by-products and the main applications focusing on rice husk combustion and ash recycling.

    Science.gov (United States)

    Moraes, Carlos A M; Fernandes, Iara J; Calheiro, Daiane; Kieling, Amanda G; Brehm, Feliciane A; Rigon, Magali R; Berwanger Filho, Jorge A; Schneider, Ivo A H; Osorio, Eduardo

    2014-11-01

    One of the consequences of industrial food production activities is the generation of high volumes of waste, whose disposal can be problematic, since it occupies large spaces, and when poorly managed can pose environmental and health risks for the population. The rice industry is an important activity and generates large quantities of waste. The main solid wastes generated in the rice production cycle include straw, husk, ash, bran and broken rice. As such, the aim of this article is to present a review of this cycle, the waste generated and the identification of opportunities to use them. Owing to impacts that can be minimised with the application of rice husk ash as a by-product, this work is focused on the recycling of the main wastes. In order to achieve that, we performed theoretical research about the rice production cycle and its wastes. The findings point to the existence of an environmentally suitable use for all wastes from the rice production cycle. As rice, bran and broken rice have their main use in the food industry, the other wastes are highly studied in order to find solutions instead of landfilling. Straw can be used for burning or animal feeding. The husk can be used for poultry farming, composting or burning. In the case of burning, it has been used as biomass to power reactors to generate thermal or electrical energy. This process generates rice husk ash, which shows potential to be used as a by-product in many different applications, but not yet consolidated. © The Author(s) 2014.

  6. Strength and fracture energy of foamed concrete incorporating rice husk ash and polypropylene mega-mesh 55

    Science.gov (United States)

    Jaini, Z. M.; Rum, R. H. M.; Boon, K. H.

    2017-10-01

    This paper presents the utilization of rice husk ash (RHA) as sand replacement and polypropylene mega-mesh 55 (PMM) as fiber reinforcement in foamed concrete. High pozzolanic reaction and the ability to become filler make RHA as a strategic material to enhance the strength and durability of foamed concrete. Furthermore, the presence of PMM optimizes the toughness of foamed concrete in resisting shrinkage and cracking. In this experimental study, cube and cylinder specimens were prepared for the compression and splitting-tensile tests. Meanwhile, notched beam specimens were cast for the three-point bending test. It was found that 40% RHA and 9kg/m3 PMM contribute to the highest strength and fracture energy. The compressive, tensile and flexural strengths are 32MPa, 2.88MPa and 6.68MPa respectively, while the fracture energy achieves 42.19N/m. The results indicate high potential of RHA and PMM in enhancing the mechanical properties of foamed concrete.

  7. Esterification of oil adsorbed on palm decanter cake into methyl ester using sulfonated rice husk ash as heterogeneous acid catalyst

    Science.gov (United States)

    Hindryawati, Noor; Erwin, Maniam, Gaanty Pragas

    2017-02-01

    Palm Decanter cake (PDC) which is categorized as the waste from palm oil mill has been found to contain residual crude palm oil. The oil adsorbed on the PDC (PDC-oil) can be extracted and potentially used as feedstock for biodiesel production. Feedstock from waste like PDC-oil is burdened with high free fatty acids (FFAs) which make the feedstock difficult to be converted into biodiesel using basic catalyst. Therefore, in this study, a solid acid, RHA-SO3H catalyst was synthesized by sulfonating rice husk ash (RHA) with concentrated sulfuric acid. The RHA-SO3H prepared was characterized with TGA, FTIR, BET, XRD, FE-SEM, and Hammett indicators (methyl red, bromophenol blue, and crystal violet). PDC was found to have about 11.3 wt. % oil recovered after 1 hour extraction using ultrasound method. The presence of sulfonate group was observed in IR spectrum, and the surface area of RHA-SO3H was reduced to 37 m2.g-1 after impregnation of sulfonate group. The RHA-SO3H catalyst showed that it can work for both esterification of free fatty acid which is present in PDC-oil, and transesterification of triglycerides into methyl ester. The results showed highest methyl ester content of 70.2 wt.% at optimal conditions, which was 6 wt.% catalyst amount, methanol to oil molar ratio of 17:1 for 5 hours at 120 °C.

  8. Thermodynamic and kinetic studies of biosorption of iron and manganese from aqueous medium using rice husk ash

    Science.gov (United States)

    Adekola, F. A.; Hodonou, D. S. S.; Adegoke, H. I.

    2016-11-01

    The adsorption behavior of rice husk ash with respect to manganese and iron has been studied by batch methods to consider its application for water and waste water treatment. The optimum conditions of adsorption were determined by investigating the effect of initial metal ion concentration, contact time, adsorbent dose, pH value of aqueous solution and temperature. Adsorption equilibrium time was observed at 120 min. The adsorption efficiencies were found to be pH dependent. The equilibrium adsorption experimental data were found to fit the Langmuir, Freundlich and Temkin isotherms for iron, but fitted only Langmuir isotherm for manganese. The pseudo-second order kinetic model was found to describe the manganese and iron kinetics more effectively. The thermodynamic experiment revealed that the adsorption processes involving both metals were exothermic. The adsorbent was finally applied to typical raw water with initial manganese and iron concentrations of 3.38 mg/l for Fe and 6.28 mg/l, respectively, and the removal efficiency was 100 % for Mn and 70 % for Fe. The metal ions were desorbed from the adsorbent using 0.01 M HCl, it was found to quantitatively remove 67 and 86 % of Mn and Fe, respectively, within 2 h. The results revealed that manganese and iron are considerably adsorbed on the adsorbent and could be an economic method for the removal of these metals from aqueous solutions.

  9. A Novel MK-based Geopolymer Composite Activated with Rice Husk Ash and KOH: Performance at High Temperature

    Directory of Open Access Journals (Sweden)

    M. A. Villaquirán-Caicedo

    2017-02-01

    Full Text Available Geopolymers were produced using an environmentally friendly alkali activator (based on Rice Husk Ash and potassium hydroxide. Aluminosilicates particles, carbon and ceramic fibres were used as reinforcement materials. The effects of reinforcement materials on the flexural strength, linear-shrinkage, thermophysical properties and microstructure of the geopolymers at room and high temperature (1200 ÅãC were studied. The results indicated that the toughness of the composites is increased 110.4% for geopolymer reinforced by ceramic fibres (G-AF at room temperature. The presence of particles improved the flexural behaviour 265% for geopolymer reinforced by carbon fibres and particles after exposure to 1200 .C. Linear-shrinkage for geopolymer reinforced by ceramic fibres and particles and the geopolymer G-AF compared with reference sample (without fibres and particles is improved by 27.88% and 7.88% respectively at 900 ÅãC. The geopolymer materials developed in this work are porous materials with low thermal conductivity and good mechanical properties with potential thermal insulation applications for building applications.

  10. Synthesis of ZSM-5 zeolite from coal fly ash and rice husk: characterization and application for partial oxidation of methane to methanol

    Science.gov (United States)

    Krisnandi, Y. K.; Yanti, F. M.; Murti, S. D. S.

    2017-04-01

    Indonesian fly ash (SiO2/Al2O3 mole ratio = 3.59) was used together with rice husk (SiO2 92%) as raw material for mesoporous ZSM-5 zeolite synthesis. Prior being used, coal fly ash and rice husk were subjected to pre-treatment in order to extract silicate (SiO4 4-) and aluminate (AlO4 5-) and to remove the impurities. Then the ZSM-5 zeolite were synthesized through hydrothermal treatment using two types of templates (TPAOH and PDDA). The as-synthesized ZSM-5 was characterized using FTIR, XRD, SEM-EDX, and BET. The result of FTIR showed peaks at 1250-950 cm-1 (v asymetric T-O), 820-650 cm-1 (v symetric T-O), and at 650-500 cm-1 confirming the presence of the five number ring of the pentasil structure. The result of XRD showed the appearance of certain peaks in the position 2 theta between 7-9° and 22-25° indicative of ZSM-5 structure, but also showed the pattern of low intensity magnetite and hematite. The SEM image showed the rough surface of hexagonal crystals from ZSM-5 structure, indicative of mesoporosity in the structure. EDX result showed Si/Al ratio of 20, while surface area analysis gave SA of 43.16. The ZSM-5 zeolites then was modified with cobalt oxide through impregnation method. The catalytic activity as heterogeneous catalysts in partial oxidation of methane was tested. The result showed that hence the catalytic activity of ZSM-5 and Co/ZSM-5 from fly ash and rice husk were still inferior compared to the pro-analysis sourced-counterpart, they were potential to be used as catalyst in the partial oxidation of methane to methanol.

  11. Evaluation Some Properties of NanoMetakaolin or Rice Husk Ash Cement Mortar and its Resistance to Elevated Temperature

    Directory of Open Access Journals (Sweden)

    Jassim Atiya Alwan

    2016-12-01

    Full Text Available The objective of this research is to find the optimum value of some properties like compressive, flexural strength of blended cement mortar by nanometakaolin ( NMK or rice husk ash (RHA and to evaluate the effect of high temperature on these properties. The ordinary Portland cement(OPC of mortar was partially substituted by NMK or RHA of 5,10,15 and 20% by weight of cement. (108 control and blended specimens were casted and tested at ambient temperature (33 ºC for compressive and flexural strength for 28 and 90 days. Another (270 of the control and blended specimens were casted and cured for 90 days and exposed to elevated temperature of a gradual increase in temperature up to 200 ºC,300 ºC, 400 ºC,600 ºC and 800 ºC for two hours in an electrical furnace and they were under the same previous tests. The test results at ambient temperature indicate that the optimum compressive and flexural strength was with ratio of 15% NMK cement replacement in mortar for 28 and 90 days but for RHA was ratio of 10% for 28 days and 15% of cement weight in mortar for 90 days compared to control specimens. The results of exposing control and blended specimens of (90 days to elevated temperature showed that the optimum strength for control and the best MK replacement ratio were found at 200 ºC, and the best RHA replacement ratio specimens was found at 300 ºC. It is also found that exposing the mortar to more than these temperatures destroyed its strength and it was detrimental to its properties.

  12. Characterization, treatment and utilization of rice husk ash in production processes of the industrial branch; Caracterizacao, tratamento e aproveitamento das cinzas da casca do arroz em processos produtivos do ramo industrial

    Energy Technology Data Exchange (ETDEWEB)

    Stracke, Marcelo Paulo; Schmidt, Julia Isabel; Steffen, Ana Cristina; Sokolovicz, Boris; Kieckow, Flavio, E-mail: stracke@santoangelo.uri.br [Universidade Regional Integrada do Alto Uruguai e das Missoes (URI), Santo Angelo, RS (Brazil)

    2016-07-01

    The rice husk ash (CCA) is a black powder rich in silica (contents above 90%) with many industrial applications. The ash was obtained from a rice processing industry in the state of Rio Grande do Sul. In this work the purpose is to characterize the rice husk ash and eliminate the residual carbon by methods such as acid leaching. The white ash is obtained by a chemical process followed by heating between 600 and 800 °C. The results were analyzed in DR-X, TGA and DSC. The DR-X analysis showed that the samples present high levels of silica in the crystalline form of quartz, cristobalite and tridymite. The white ash was obtained with high purity and presented a good result in the manufacture of paints. (author)

  13. Preparation of porous bio-char and activated carbon from rice husk by leaching ash and chemical activation.

    Science.gov (United States)

    Ahiduzzaman, Md; Sadrul Islam, A K M

    2016-01-01

    Preparation porous bio-char and activated carbon from rice husk char study has been conducted in this study. Rice husk char contains high amount silica that retards the porousness of bio-char. Porousness of rice husk char could be enhanced by removing the silica from char and applying heat at high temperature. Furthermore, the char is activated by using chemical activation under high temperature. In this study no inert media is used. The study is conducted at low oxygen environment by applying biomass for consuming oxygen inside reactor and double crucible method (one crucible inside another) is applied to prevent intrusion of oxygen into the char. The study results shows that porous carbon is prepared successfully without using any inert media. The adsorption capacity of material increased due to removal of silica and due to the activation with zinc chloride compared to using raw rice husk char. The surface area of porous carbon and activated carbon are found to be 28, 331 and 645 m(2) g(-1) for raw rice husk char, silica removed rice husk char and zinc chloride activated rice husk char, respectively. It is concluded from this study that porous bio-char and activated carbon could be prepared in normal environmental conditions instead of inert media. This study shows a method and possibility of activated carbon from agro-waste, and it could be scaled up for commercial production.

  14. Effects of chickpea husk on the baking properties of chapattis

    OpenAIRE

    Inam, A.K.M.S; M. A. Haque; Shams-Ud-Din, M.; Easdani, M.

    2010-01-01

    Chickpea husks were extracted by non-alkaline aqueous extraction process and then ground in flour mill. The unextracted husks were also ground in flour mill. The analysis of chickpea husk showed that extracted husk was lower in moisture, protein, ash and fat but higher in carbohydrate and crude fiber contents compared to unextracted husk. Chapattis were prepared incorporating different levels of extracted and unextracted chickpea husk and evaluated for various quality parameters as weight, wi...

  15. Phytoremediation of Gold Mine Tailings Amended with Iron-Coated and Uncoated Rice Husk Ash by Vetiver Grass (Vetiveria zizanioides (Linn. Nash

    Directory of Open Access Journals (Sweden)

    F. S. Tariq

    2016-01-01

    Full Text Available This study was undertaken to determine the effects of rice husk ash (RHA and iron-coated rice husk ash (Fe-RHA on phytoavailability of As, Cd, Cr, Cu, Mn, Pb, and Zn to vetiver grass grown in gold mine tailings amended with either RHA or Fe-RHA at 0%, 5%, 10%, and 20% (w/w. The results showed that the RHA amended tailings recorded higher concentration of As in the shoot and the root and higher concentration of Cr and Mn in the root compared to the untreated tailings which was used as a control. The biological accumulation coefficient (BAC and bioconcentration factor (BCF values of the vetiver grass for As and Zn increased with RHA application rate but the biological transfer coefficient (BTC values of As and Zn were decreased. In Fe-RHA amended samples, As concentration in the shoot and root concentrations of Cd and Zn were significantly higher compared to the control. The Fe-RHA treated samples had lower BAC and BTC values for As and Zn than the control. However, the BCF values for those elements were higher than the control. The concentration of Pb was not detected in any of the samples.

  16. Effects of the addition of oil shale ash and coal ash on physic-chemical properties of CPJ45 cement

    Directory of Open Access Journals (Sweden)

    Nabih K.

    2014-04-01

    Full Text Available We focused our research on recycling industrial wastes, fly ash (F.A, bottom ash (B.A and oil shale ash (S.A in cement production. The study concerns physico-chemical characterization of these products and the influence of their addition on the mechanical proprieties of the CPJ45 cement. XRF allowed us to rank the three additives used according to their contents on major oxides. Coal ashes belong to the class F, and thus possess poozzolanic properties and oil shale ash belongs to the class C and possesses hydraulic and poozolanic properties. The crystalline phases constituting each ash were analysed by XRD. We observe in bottom ash the presence of quartz and mullite. The same crystals are found in fly ash with hematite and magnetite. Oil shale ash is composed of quartz, anhydrite, gehlenite, wollastonite and periclase. The microstructures of fly ash and bottom ash were studied using SEM. The bottom ash was composed respectively of fine particles that are generally irregularly shaped, their dimensions are between 5 and 28μm and of big particles(300 μm. The EDX analysis coupled with an electronic microscope provided some information about the major elements that constitute our samples. The dehydrations of anhydrous and three days hydrated cement were examined by DSC. For hydrated cements we noticed endothermic peaks related to the dehydration of CSH, CH and decomposition of carbonates. The study of the mechanical properties of CPJ45 cement by adding different proportions of fly ash, bottom ash and oil shale ash helped clarifying the percentage of ash that leaded to improve the 28 days mechanical strength. The results show that the cements studied have their maximum mechanical resistance with the addition at 7% of fly ash or 10% of oil shale ash.

  17. effect of aluminum dross and rice husk ash on thermal and moulding

    African Journals Online (AJOL)

    HOD

    AlDr addition but decreased from 4.0-2.8% for0-6 wt. % RHA addition in ... traced to problems faced by foundry industries in developing ... industry [3]. Formulation of moulding sand mix is targeted at good moulding properties and other specific properties desired in the microstructure of the final cast product. Moulding sand ...

  18. Performance at high temperature of alkali-activated slag pastes produced with silica fume and rice husk ash based activators

    Directory of Open Access Journals (Sweden)

    Bernal, S. A.

    2015-06-01

    Full Text Available This study assessed the mechanical properties, and structural changes induced by high temperature exposure, of alkali-silicate activated slag cements produced with sodium silicates derived from silica fume (SF and rice husk ash (RHA. Similar reaction products were identified, independent of the type of silicate used, but with subtle differences in the composition of the C-S-H gels, leading to different strength losses after elevated temperature exposure. Cements produced with the alternative activators developed higher compressive strengths than those produced with commercial silicate. All samples retained strengths of more than 50 MPa after exposure to 600 °C, however, after exposure to 800 °C only the specimens produced with the RHA-based activator retained measurable strength. This study elucidated that silicate-activated slag binders, either activated with commercial silicate solutions or with sodium silicates based on SF or RHA, are stable up to 600 °C.Este estudio evaluó las propiedades mecánicas, y cambios estructurales inducidos por exposición a temperaturas elevadas, de cementos de escoria activada alcalinamente producidos con silicatos sódicos derivados de humo de sílice (SF y ceniza de cascarilla de arroz (RHA. Se identificaron productos de reacción similares, independiente del tipo de silicato utilizado, pero con diferencias menores en la composición de las geles C-S-H, lo cual indujo diferentes pérdidas de resistencia posterior a exposición a temperaturas elevadas. Los cementantes producidos con los activadores alternativos desarrollaron resistencias a la compresión más altas que aquellos producidos con silicato comercial. Todas las muestras retuvieron resistencias de más de 50 MPa posterior a la exposición a 600 °C, sin embargo, posterior a la exposición a 800 °C únicamente muestras producidas con activadores de RHA retuvieron resistencias medibles. Este estudio elucidó que cementantes de escoria activada con

  19. Utilization of rice husk ash as filler for polyamide 6 and ionizing radiation effect studies on this composite;Utilizacao da cinza da casca de arroz como carga em matriz de poliamida 6 submetida a radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Ferro, Waldir Pedro

    2009-07-01

    In order to improve the dimensional stability, as well as, electrical, mechanical and thermal properties of polymers, new filler to this purpose has been developed. The mos applied filler to propitiate the features previously mentioned are the glass and carbon fibers, the mineral filler as the calcium carbonate, the talc and the micro glass sphere. The main aim of this work was to study the rice husk ash as filler for polyamide 6 and ionizing radiation effect studies on this composite, irradiated by electron beam at different doses, since it is constituted of at least 90% of silicon dioxide, and compared with the talc which is the most applied mineral filler. This comparison was made from a compound made through the refined rice husk ash and the polyamide 6 (PA 6), which is one of the main engineering plastic with applications in several productive areas. The samples were injected and irradiated in a electron accelerator. Afterwards, their mechanical and thermal properties were measured. It was also inject automotive parts to verify the processing of the PA 6 with CCA. The results showed that the use of the rice husk ash as filler for polyamide 6 composite is technically and economically viable. The irradiation of the studied composite (PA 6 with 30% of rice husk ash) did not provide any improvement for the mechanical and thermal properties previously appraised. (author)

  20. Cinética de vulcanização de composições de borracha natural com incorporação de cinza de casca de arroz Vulcanization kinetics of natural rubber filled with rice husk ash

    Directory of Open Access Journals (Sweden)

    Helson M. da Costa

    2003-06-01

    Full Text Available Cinza da casca de arroz foi incorporada em borracha natural (NR utilizando-se um misturador de cilindros. O sistema de vulcanização convencional (CV foi escolhido e os estudos sobre a cura das composições foram conduzidos em um Curômetro TI-100. As curvas de torque foram obtidas em 150, 160, 170 e 180 °C. A velocidade global e a energia de ativação aparente para o processo de vulcanização foram calculadas para cada composição, assumindo que a vulcanização segue uma cinética de primeira ordem. Para fins de comparação, duas cargas comerciais, sílica precipitada (Zeosil-175 e negro de fumo (N762, foram também usadas. Foi observado que a adição da cinza da casca de arroz às composições de NR, em comparação às outras cargas utilizadas, aumentou a velocidade de reticulação e diminuiu a energia de ativação aparente de modo mais marcante.Rice husk ash was incorporated into natural rubber (NR using a laboratory size two-roll mill. A conventional vulcanization system (CV was chosen and cure studies were carried out on a TI-100 Curometer. The torque curves were obtained at 150, 160, 170, and 180 °C. The overall rate and the apparent activation energy for the vulcanization process were calculated for each compound assuming that vulcanization follows first-order kinetics. For the purpose of comparison, two commercial fillers, precipitated silica (Zeosil-175 and carbon black (N762, were also used. In comparison to the other fillers used, the addition of rice husk ash to NR compounds increased the crosslinking rate and lowered the apparent activation energy in a more marked way.

  1. Pengaruh pemberian abu sekam padi sebagai bahan desikan pada penyimpanan benih terhadap daya tumbuh dan pertumbuhan bibit kakao (The effects of rice husk ash as desiccation material of seed storage on viability and cocoa seedling growth.

    Directory of Open Access Journals (Sweden)

    Pudji Rahardjo

    2012-08-01

    Full Text Available Rice husk ash as desiccation material can be used to maintain seed viability in storage through its ability to absorb humidity during its storage. High relative humidity caused seed moisture content to increase so the respiration rate of seed increases and uses faster food stock. Finally the viability of seed is lost. A research on use of rice husk ash as desiccation material of cocoa seed storage was conducted in Agronomy Laboratory and Kaliwining Experimental Station, Indonesian Coffee and Cocoa Research Institute. Completely Randomized Design was used in this research with treatment of rice husk ash application on cocoa seed as follows: 0 g/100 seeds (A, 5 g/100 seeds (B, 10 g/100 seeds (C, 15 g/100 seeds (D, and 20 g/100 seeds (E. This experiment used four replications. Cocoa seeds were stored in plastic bag within carton box in ambient temperature. The storage periods were 1, 2, and 3 weeks, and parameters of observation consisted of electrical conductivity of dipped water of cocoa seeds, percentage of seed germination, percentage of seed emergence, early growth parameters at one month old including seedlings height of seedling, diameter, leaf number, root length, and dry weight. The result of the experiment showed that the use of rice husk ash at 5-10 g/100 seeds could maintain electrical conductivity of dipped water at low level, percentage of seed germination at 99-100 % and percentage of seed emergence at 79-91% after two weeks storage. The use of rice husk ash at 5-10 g/100 seeds after two weeks storage affected height of cacao seedling, but did not affected stem diameters, leaf numbers, root lengths, and dry weights

  2. Performance of Low-Volume Roads with Wearing Course Layer of Silty Sandy Soil Modified with Rice Husk Ash and Lime

    Energy Technology Data Exchange (ETDEWEB)

    Behak Katz, L.; Musso Laespiga, M.

    2016-07-01

    Rice husk ash (RHA) is a by-product of rice milling. Its use as soil stabilizer is a way to replace the final disposal with environmental benefit. However, RHA is not cementitious itself but when mixed with lime forms cements which improve the soil properties. A research of performance of a silty sandy soil modified with RHA and lime as wearing course layer of low-volume roads was conducted through two full-scale test sections with different pavements built in Artigas, northern Uruguay. The alkaline reactivity of RHA is low because the husk burning is not controlled. The soil-RHA-lime mix design was conducted according to the Thompson’s Method. The pavement test sections were monitored through deflection measures by Benkelman beam and observations of surface condition. The deflections decreased over time in both test sections due to the development of cementation of the study materials. After one year, the dust emission was reduced, the wet skid resistance of pavement surfaces improved and there was not rutting. The researched pavements have had a good performance under the existing traffic and environmental conditions, demonstrating that wearing course layer of silty sand modified with RHA and lime is an alternative to improve the condition of low-volume roads and to replace the final disposal of RHA, with environmental, social and economic benefits. (Author)

  3. Effect of sintering temperature on mechanical behaviour and bioactivity of sol-gel synthesized bioglass-ceramics using rice husk ash as a silica source

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, J.P., E-mail: jyotiprakash_nitrkl@rediffmail.com [Department of Ceramic Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India); Bera, J., E-mail: bera@rediffmail.com [Department of Ceramic Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India)

    2010-11-01

    Bioglass-ceramics with SiO{sub 2}-Na{sub 2}O-CaO composition was prepared by sol-gel method using rice husk ash as a silica source. Material was sintered at different temperatures ranging from 900 to 1050 deg. C for 2 h. Phase-formation behaviour, densification characteristics, and mechanical strength of glass-ceramics were investigated. The material sintered at 1000 deg. C showed a good mechanical strength. Mechanical properties were correlated with microstructural features. Both in vitro bioactivity and biodegradability of sintered material were investigated by incubating in simulated body fluid and Tris buffer solution, respectively. Scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were used to investigate the surface deposition during body fluid incubation. Both bioactivity and degradability decreased with increase in sintering temperature.

  4. Effect of sintering temperature on mechanical behaviour and bioactivity of sol-gel synthesized bioglass-ceramics using rice husk ash as a silica source

    Science.gov (United States)

    Nayak, J. P.; Bera, J.

    2010-11-01

    Bioglass-ceramics with SiO2-Na2O-CaO composition was prepared by sol-gel method using rice husk ash as a silica source. Material was sintered at different temperatures ranging from 900 to 1050 °C for 2 h. Phase-formation behaviour, densification characteristics, and mechanical strength of glass-ceramics were investigated. The material sintered at 1000 °C showed a good mechanical strength. Mechanical properties were correlated with microstructural features. Both in vitro bioactivity and biodegradability of sintered material were investigated by incubating in simulated body fluid and Tris buffer solution, respectively. Scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were used to investigate the surface deposition during body fluid incubation. Both bioactivity and degradability decreased with increase in sintering temperature.

  5. Comparison between rice husk ash and commercial silica as filler in polymeric composites; Comparacao de cinza de casca de arroz e silica comercial como carga em compositos polimericos

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, I.J.; Calheiro, D.; Santos, E.C.A. dos; Oliveira, R.; Rocha, T.L.A.C.; Moraes, C.A.M., E-mail: ijk.fernandes@gmail.com [Universidade do Vale do Rio dos Sinos (UNISINOS), Sao Leopoldo, RS (Brazil). Pos-Graduacao em Engenharia Civil

    2014-07-01

    The use of rice husk ash (RHA) as filler in polymeric materials has been studied in different polymers. Research reported that RHA may successfully replace silica. The silica production process using ore demands high energy input and produces considerable amounts of waste. Therefore, the replacement of silica by RHA may be economically and environmentally advantageous, reducing environmental impact and adding value to a waste material. In this context, this study characterizes and compares RHA of different sources (travelling grate reactor and fluidized bed reactor) with commercially available silicas to assess performance as filler in polymeric materials. Samples were characterized by X-ray fluorescence, loss on ignition, X-ray diffraction, grain size, specific surface area and specific weight. The results show that RHA may be used as a filler in several polymeric materials.(author)

  6. Uso da cinza da casca de arroz como carga em matrizes de poliamida 6 e poliamida 6.6 Study of the use of rice husk ash as filler in polyamide 6 and polyamide 6.6 matrices

    Directory of Open Access Journals (Sweden)

    Waldir P. Ferro

    2007-09-01

    Full Text Available Este trabalho avalia a utilização da cinza da casca de arroz como carga estrutural em poliamida 6 e poliamida 6.6. Estas matrizes poliméricas são importantes plásticos de engenharia com aplicações em várias áreas. Fez-se uma comparação das propriedades mecânicas de resistência à tração, resistência à flexão, resistência ao impacto e a propriedade térmica de fio incandescente entre compostos de poliamida 6 e poliamida 6.6, com 30% de cinza da casca de arroz, e compostos de poliamidas com 30% de talco. Os resultados das propriedades mecânicas e térmica mostraram um comportamento semelhante entre as poliamidas com 30% de cinza da casca de arroz e as poliamidas com 30% de talco. Assim sendo, o uso da cinza da casca de arroz é uma alternativa viável para a substituição do talco como carga, como foi comprovado ao confeccionar um conector elétrico injetado com poliamida 6.6 com 30% de cinza da casca de arroz. Portanto, este trabalho contribui para a diminuição de um problema ambiental, possibilitando o uso da cinza da casca de arroz em processos industriais.This work evaluates the technical viability of the use of rice husk ash as filler in polyamide 6 and polyamide 6.6 which are one of the main engineering plastics with applications in several areas. A comparison was made among the mechanical properties of tensile strength, flexural strength, impact strength and the thermal property of glow wire of polyamide 6 and polyamide 6.6 compounds with 30% of rice husk ash and the compounds of these polyamides with 30% of talc. The results of mechanical and thermal properties showed a similar behavior among the polymeric matrices of polyamide with 30% of rice husk ash and 30% of talc. This was verified by the manufacturing of an electric connector injected with polyamide 6.6 with 30% of rice husk ash. Thus, the use of rice husk ash is a viable alternative for the substitution of talc as filler. So, this work contributes for

  7. Effects of coal and wheat husk additives on the physical, thermal and mechanical properties of clay bricks

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S.; Iqbal, Y.; Muhammad, R.

    2017-07-01

    The use of by-products as additives in brick industry is gaining increased research attention due to their effective role in decreasing the total energy needs of industrial furnaces. In addition, these additives leave pores upon burning, causing a decrease in thermal conductivity and affect the mechanical properties of bricks as well. In the present study, various proportions of coal and wheat husk were used as additives in the initial ingredients of clay bricks. Microstructure, thermal conductivity, coefficient of thermal diffusivity, water absorption, shrinkage, compressive strength and bulk density of fired clay bricks with and without additives were investigated. Clay bricks containing 5–15wt.% additives were found to be within the permissible limits for most of the recommended standard specifications. (Author)

  8. Effects of coal and wheat husk additives on the physical, thermal and mechanical properties of clay bricks

    Directory of Open Access Journals (Sweden)

    Safeer Ahmad

    2017-05-01

    Full Text Available The use of by-products as additives in brick industry is gaining increased research attention due to their effective role in decreasing the total energy needs of industrial furnaces. In addition, these additives leave pores upon burning, causing a decrease in thermal conductivity and affect the mechanical properties of bricks as well. In the present study, various proportions of coal and wheat husk were used as additives in the initial ingredients of clay bricks. Microstructure, thermal conductivity, coefficient of thermal diffusivity, water absorption, shrinkage, compressive strength and bulk density of fired clay bricks with and without additives were investigated. Clay bricks containing 5–15 wt.% additives were found to be within the permissible limits for most of the recommended standard specifications.

  9. Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash

    Directory of Open Access Journals (Sweden)

    Ali Jabbar Abed Al-Nidawi

    Full Text Available In this study, an investigation was conducted to explore and synthesize silicate (SiO2 glass from waste rice husk ash (RHA. MnO2 doped zinc silicate glasses with chemical formula [(ZnO55 + (WRHA45]100-X[MnO2]X, (where X = 0, 1, 3 and 5 wt% was prepared by conventional melt quenching technique. The glass samples were characterized using energy dispersive X-ray fluorescence (EDXRF, X-ray diffraction (XRD, field emission scanning electron microscopy (FESEM, Fourier transform infrared (FTIR spectroscopy, and ultraviolet–visible (UV–Vis spectroscopy. The results revealed that by increasing the concentration of MnO2, the color of glass samples changed from colorless to brown and the density of glass increased. XRD results showed that a broad halo peak which centered on the low angle (2θ = 30° indicated the amorphous nature of the glass. FTIR results showed basic structural units of Si-O-Si in non-bridging oxygen, Si-O and Mn-O in the glass network. FESEM result showed a decreasing porosity with an increasing MnO2 content, which was attributed to the Mn ions resort to occupy interstitial sites inside the pores of glass. Besides, the absorption intensity of glass increased and the band gap value decreased with increasing the MnO2 percentage. In this synthesized glass system of MnO2 doped zinc silicate glasses using RHA as a source of silica, the MnO2 affect most of the properties of the glass system under investigation. Keywords: Rice husk, Manganese dioxide, Glass, Zinc silicate, Sintering, Optical properties

  10. Suppression of Psyllium Husk Suspension Viscosity by Addition of Water Soluble Polysaccharides.

    Science.gov (United States)

    Kale, Madhuvanti S; Yadav, Madhav P; Hanah, Kyle A

    2016-10-01

    Psyllium seed husk is an insoluble dietary fiber with many health benefits. It can absorb many times its weight in water, forming very viscous suspensions, which have low palatability and consumer acceptance. We report here a novel approach for decreasing its viscosity, involving inclusion of a soluble polysaccharide in the suspension. This leads to a drastic decrease (up to 87%) in viscosity of suspensions, while maintaining the same dosage level of psyllium and also delivering a significant amount of soluble dietary fiber such as corn bio-fiber gum in a single serving. Four soluble polysaccharides with a range of molecular weights and solution viscosities have been studied for their viscosity suppression effect. Besides improving palatability, another advantage of this approach is that it makes it possible to deliver 2 different dietary fibers in significant quantities, thus offering even greater health benefits. © 2016 Institute of Food Technologists®.

  11. Adsorption of Pb(II) using silica gel composite from rice husk ash modified 3-aminopropyltriethoxysilane (APTES)-activated carbon from coconut shell

    Science.gov (United States)

    Yusmaniar, Purwanto, Agung; Putri, Elfriyana Awalita; Rosyidah, Dzakiyyatur

    2017-03-01

    Silica gel modified by 3-aminopropyltriethoxysilane (APTES) was synthesized from rice husk ash combined with activated carbon from coconut shell yielded the composite adsorbent. The composite was characterized by Fourier Transform Infra Red spectroscopy (FT-IR), Electron Dispersive X-Ray (EDX), Surface Area Analyzer (SAA) and adsorption test by Atomic Absorption Spectrometry (AAS). This composite adsorbent has been used moderately for the removal of lead ions from metal solutions and compared with silica gel modified APTES and activated carbon. The adsorption experiments of Pb -ions by adsorbents were performed at different pH and contact time with the same metal solutions concentration, volume solution, and adsorbent dosage. The optimum pH for the adsorption was found to be 5.0 and the equilibrium was achieved for Pb with 20 min of contact time. Pb ions adsorption by composite silica gel modified APTES-activated carbon followed by Langmuir isotherm model with qmax value of 46.9483 mg/g that proved an adsorbent mechanism consistent to the mechanism of monolayer formation.

  12. Microstructure and mechanical behavior of stir-cast Zn–27Al based composites reinforced with rice husk ash, silicon carbide, and graphite

    Directory of Open Access Journals (Sweden)

    Kenneth Kanayo Alaneme

    2017-04-01

    Full Text Available The microstructure and mechanical properties of Zn–27Al based composites reinforced with rice husk ash (RHA, silicon carbide (SiC, and graphite (Cg particles have been investigated. The Zn–27Al composites consisting of varied weight ratios of the reinforcing materials were produced using the stir casting process. Hardness test, tensile properties evaluation, fracture toughness determination, and microstructural examination, were used to characterize the composites produced. Results show that the microstructures of the composites are similar, consisting of the dendritic structure of the Zn–27Al alloy matrix with fine dispersion of the reinforcing particles. The hardness of the composites decreased with increase in the weight percent of RHA (and corresponding decrease in SiC weight percent in the reinforcement. The tensile strength and yield strength decreased slightly with increase in the weight ratio of RHA in the composites with a maximum of 8.5% and 9.6% reductions respectively observed for as much as 40% RHA (corresponding to 40% reduction in SiC in the hybrid reinforcement. Although some of the composite compositions containing RHA had slightly higher % elongation values compared with those without RHA, it was generally observed that the % elongation was invariant to the composite RHA content. The fracture toughness of the composites increases with increase in the weight percent of RHA with as much as a 20% increase obtained for as much as 40% RHA (corresponding to 40% reduction in SiC in the hybrid reinforcement.

  13. Comparison of Acid Red 114 Dye Adsorption by Fe3O4 and Fe3O4 Impregnated Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    Gul Kaykioglu

    2016-01-01

    Full Text Available The removal of Acid Red 114 (AR114 dye by adsorption process, using the magnetic nanoparticle (RHA-MNP which is produced from rice husk ash burned at 300°C and the magnetic nanoparticle (MNP, Fe3O4, was studied. Batch processes were used under different test parameters: pH (2, 4, 6, and 10 and without pH, initial dye concentration (20, 40, 60, 80, and 100 mg/L, and contact time (0, 1, 5, 10, 15, 30, 45, 60, 90, and 150 min. Optimum conditions for AR114 removal were found to be at natural pH (pH without correction for both adsorbents. Freundlich isotherm was found to be more consistent for MNP and Langmuir isotherm was found to be more consistent for RHA-MNP. The maximum adsorption capacities of MNP and RHA-MNP adsorbents for AR114 dye were equal to 111 mg/g. The kinetic experimental data fitted the pseudo-second-order model for both MNP and RHA-MNP. It can be concluded that RHA-MNP which is a waste could be used as low-cost adsorbent to remove AR114 from aqueous solution.

  14. Microstructural characteristics, mechanical and wear behaviour of aluminium matrix hybrid composites reinforced with alumina, rice husk ash and graphite

    Directory of Open Access Journals (Sweden)

    Kenneth Kanayo Alaneme

    2015-09-01

    Full Text Available The microstructural characteristics, mechanical and wear behaviour of Aluminium matrix hybrid composites reinforced with alumina, rice husk ash (RHA and graphite were investigated. Alumina, RHA and graphite mixed in varied weight ratios were utilized to prepare 10 wt% hybrid reinforced Al-Mg-Si alloy based composites using two-step stir casting. Hardness, tensile properties, scanning electron microscopy, and wear tests were used to characterize the composites produced. The results show that Hardness decreases with increase in the weight ratio of RHA and graphite in the composites; and with RHA content greater than 50%, the effect of graphite on the hardness becomes less significant. The tensile strength for the composites containing o.5wt% graphite and up to 50% RHA was observed to be higher than that of the composites without graphite. The toughness values for the composites containing 0.5wt% graphite were in all cases higher than that of the composites without graphite. The % Elongation for all composites produced was within the range of 10–13% and the values were invariant to the RHA and graphite content. The tensile fracture surface morphology in all the composites produced was identical characterized with the presence of reinforcing particles housed in ductile dimples. The composites without graphite exhibited greater wear susceptibility in comparison to the composite grades containing graphite. However the wear resistance decreased with increase in the graphite content from 0.5 to 1.5 wt%.

  15. Glass-ceramic materials of system MgO-Al{sub 2}O{sub 3}-SiO{sub 2} from rice husk ash; Materiales vitroceramicos del sistema MgO-Al2O3-SiO2 a partir de ceniza de cascara de arroz

    Energy Technology Data Exchange (ETDEWEB)

    Martin, M. I.; Rincon, J. M.; Andreola, F.; Barbieri, L.; Bondioli, F.; Lancellotti, I.; Romero, M.

    2011-07-01

    This wok shows the results of a valorisation study to use rice husk ash as raw material to develop glass-ceramic materials. An original glass has been formulated in the base system MgO-Al{sub 2}O{sub 3}-SiO{sub 2} with addition of B{sub 2}O{sub 3} and Na{sub 2}O to facilitate the melting and poring processes. Glass characterization was carried out by determining its chemical composition. Sintering behaviour has been examined by Hot Stage Microscopy (HSM). Thermal stability and crystallization mechanism have been studied by Differential Thermal Analysis (DTA). Mineralogy analyses of the glass-ceramic materials were carried out using X-ray Diffraction (XRD). Results show that it is possible to use ash rice husk to produce glass-ceramic materials by a sinter crystallization process, with nepheline (Na{sub 2}O-Al{sub 2}O{sub 3}-SiO{sub 2}) as major crystalline phase in the temperature interval 700-950 degree centigrade and forsterite (2MgO-SiO{sub 2}) at temperatures above 950 degree centigrade. (Author) 15 refs.

  16. removal of heavy metal ions from aqueous solution using rice husks ...

    African Journals Online (AJOL)

    User

    ABSTRACT. This study reports on the preparation and characterization of rice husks-based adsorbents and their application in the removal of heavy metal ions from aqueous solution. Three different adsorbents were developed: rice husks ash (RHA), rice husks ash-derived silica (RHS) and triaminopropyl-silica hybrid ...

  17. Aplicação da cinza da casca do arroz em argamassas de assentamento Application of the rice husk ash in mortars for bricklaying

    Directory of Open Access Journals (Sweden)

    Izabelle M. T. Bezerra

    2011-06-01

    Full Text Available A cinza produzida pela queima da casca do arroz tem potencial para ser utilizada na confecção de argamassas por possuir, em sua constituição, alto teor de sílica (SiO2, podendo ser utilizada também como material pozolânico. Esta pesquisa objetivou verificar a viabilidade da utilização da cinza da casca do arroz (CCA em argamassas de assentamento. Realizou-se a caracterização química e mineralógica da CCA e se determinou o índice de atividade pozolânica. Para as argamassas foi determinado o índice de consistência e, em seguida, confeccionados corpos de prova de referência (sem CCA e também com percentuais de 6, 9, 15, 20 e 30% de CCA, como substituição parcial do cimento, para o traço 1:2:9, em massa, e ensaiados após períodos de cura de 28, 63 e 91 dias para determinação da densidade de massa no estado endurecido, absorção de água e resistência à compressão simples. Os resultados mostram que a CCA apresenta pozolanicidade e os corpos de prova com incorporação da CCA forneceram valores superiores aos de referência com relação às propriedades físicas e mecânicas, devido à provável ocorrência das reações pozolânicas e que a utilização da CCA é viável, tanto do ponto de vista técnico quanto ecológico.The ash produced by the burning of the rice husk presents potential for application in mortar production because has high silica content (SiO2, and so it can be used as pozzolan. This research aimed to verify the viability of rice husk ash (RHA added to mortars for bricklaying. Chemical and mineralogical characterization of RHA was initially carried out and the pozzolanic activity was determined. For the production of mortars, the consistence of each mixture studied was determined and then reference mortars (without CCA and mortars with incorporated RHA were produced with 6, 9, 15, 20 and 30% of RHA in partial substitution of cement for mortar 1:2:9 (mass ratio, in curing period of 28, 63 and 91 days

  18. Synthesis and characterization of chitosan-graft-poly(acrylic acid)/rice husk ash hydrogels composites; Sintese e caracterizacao de hidrogeis compositos de cinza da casca de arroz e quitosana enxertada com poli(acido acrilico)

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Francisco H.A. [Universidade Estadual Vale do Acarau - UVA, Sobral, CE (Brazil); Lopes, Gabriel V.; Pereira, Antonio G.B.; Fajardo, Andre R.; Muniz, Edvani C. [Universidade Estadual de Maringa - UEM, PR (Brazil)

    2011-07-01

    According to environmental concerns, super absorbent hydrogel composites were synthesized based on rice husk ash (RHA), an industrial waste, and Chitosan-graft-poly(acrylic acid). The WAXS and FTIR data confirmed the syntheses of hydrogel composites. The effect of crystalline or amorphous RHA on water uptake was investigated. It was found that the RHA in crystalline form induces higher water capacity (W{sub eq}) of composites hydrogels due to the fact that the intra-interactions among silanol groups on RHA make available new sites in the polymer matrix, which could interact to water. (author)

  19. Effect of additives in reducing ash sintering and slagging in biomass combustion applications

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liang

    2012-07-01

    The objective of this study was to investigate sintering and slagging behaviors of biofuels during combustion processes. Biofuels tested are derived from the agricultural sector, wood and furniture industry as well as from municipal sewage sludge. It was also the aim to test and evaluate additives that can prevent and abate biomass ash sintering by conducting laboratory and industrial scale tests. Sintering characteristics of sewage sludge ashes at elevated temperatures were investigated by means of different laboratory methods. Utilizing of phosphorus participation agents Al2(SO4)3 or Fe2(SO4)3 caused substantially high contents of aluminum or iron in the studied sewage sludge ashes, respectively. High initial melting temperatures over 1100 degrees C and low sintering tendencies were observed from the sewage sludge ashes rich in aluminum. It was related to presence and formation of the inert mineral phases such as aluminum oxide, quartz and calcium aluminum silicates in the aluminum rich sewage sludge ashes at elevated temperatures. A low melting temperature, about 994 degree C, was detected from the iron rich sewage sludge ash. Severe sintering of this sewage sludge ash was mainly due to generation of low temperature melting iron silicates, as results of interaction and re-assemblage of hematite (Fe2O3), quartz (SiO2) and alkali feldspars under heating. Fusion behaviors of corn cob ashes under rising temperatures were characterized. The work revealed that chemical compositions of corn cob ashes are dominated by potassium, silicon, chlorine and phosphorus. However, the relative concentrations of these principal elements are considerably different for three studied corn cob ashes, which have major influence on ash transformation reactions and sintering tendencies. Compared with the other two, the chemical composition of the Waimanalo corn cob (WCob) was characterized with the highest K/Cl, Si/(Ca+Mg) and (Si+P+K)/(Ca+Mg) molar ratios, which was favorable for

  20. Evaluation of Greek type Portland cement based on Megalopolis fly ash addition

    Energy Technology Data Exchange (ETDEWEB)

    Stivanakis, V.; Papamantellos, D. [University of Patras (Greece). Department of Chemical Engineering, Laboratory of Metallurgy; Galanoulis, E. [Titan Cement Company S.A., Drepano, Achaias (Greece)

    2003-04-01

    Fly-ash is considered as a fine material which is produced during firing of powdered solid fuels in steam generating plants. It is contained in the output exhaust gases and collected in the electrostatic filters. In the lignite fired power plants of Public Power Corporation in the regions of Ptolemais-Amynteon and Megalopolis 65 . 10 t/a of lignite are consumed nowadays with a corresponding fly ash production of about 13 . 10{sup 6} t/a. The utilisation of fly ash generated in Megalopolis plant ({proportional_to} 3.5 . 106 t/a) in cement industry has been investigated by the Laboratory of Metallurgy (METLAB) in collaboration with the cement company Titan and the Greek P.P.C. since 1979. The primary target of this research and development work, was to investigate the addition of Megalopolis fly ash in the manufacturing process of cement, in quantities around 10%, replacing the so-called Volcanic Rock (Santorini's earth), which was used as a pozzolanic material. Megalopolis fly ash was considered to be unsuitable for use as hydraulic powder due to its high SiO{sub 2} content ({proportional_to}50%), in contrast to Ptolemais-Amynteon fly ash, which contains high percentages of CaO (30 - 40%). The first results were very encouraging as they proved that addition of blended fly ash could be added up to 50% without considerable reduction in the compressive strength of cement. Consequently, exploitation of Megalopolis fly ash by Titan cement industry began in 1982, with the production of Greek type Portland cement that contains 15 - 20% of Megalopolis fly ash. The annual consumption of Megalopolis fly ash since 1982 is in the range of 300.000 - 500.000 t/a. In the years following 1983, a systematic investigation of the influence of Megalopolis fly ash addition, up to a content of 80% upon the technological properties of cement and concrete was carried out. The workability, compressive strength (2, 7, 28 days), long-term compressive strength (up to 180 days) and the

  1. Impact of coal fly ash addition on ash transformation and deposition in a full-scale wood suspension-firing boiler

    DEFF Research Database (Denmark)

    Wu, Hao; Bashir, Muhammad Shafique; Jensen, Peter Arendt

    2013-01-01

    Ash transformation and deposition during pulverized wood combustion in a full-scale power plant boiler of 800 MWth were studied with and without the addition of coal fly ash. The transient ash deposition behavior was characterized by using an advanced deposit probe system at two boiler locations...... with flue gas temperatures of about 1300 C and 800 C, respectively. The mechanisms of ash transformation and deposit formation were elaborated through a detailed characterization of the collected deposits and fly ashes. The results implied that during pulverized wood combustion, the formation of deposits...... constant after a few hours. The formed deposits, especially those at the location with low flue gas temperatures, contained a considerable amount of K2SO4, KCl, and KOH/K2CO3. With the addition of a large amount (about 4 times of the mass flow of wood ash) of coal fly ash to the boiler, these alkali...

  2. Study of the rice husk ash utilization as filler polypropylene matrix and ionization radiation effect on this composite; Estudos da utilizacao da cinza de casca de arroz como carga em matriz de polipropileno e do efeito da radiacao ionizante sobre este composito

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro, Eduardo de Faria

    2010-07-01

    In the first step of this work, it was evaluated the possibility of using rice husk ash as a filler in polypropylene (PP) making a comparison with talc which is the most used mineral filler in polymers. This comparison was made by using polypropylene with 20% rice husk ash as well as polypropylene with 20% talc measuring their properties. Despite the properties of the PP with 20% rice husk ash decreased compared with the composite of polypropylene with 20% talc it can be said that the rice husk ash can be used as filler for or other utilization less noble of PP . This way it is being given a destination for this residue that it is disposable in the environment contributing to its preservation, moreover reducing the product cost. This work had also as an aim to study the ionizing radiation effect in the properties of these composites. It was used the coupling agent, maleic anhydride , to verify a best sample homogenization. According to the results it can be said that PP is a semicrystalline polymer, and so it has its morphology modified when exposed to the irradiation process. This fact is due to the scission mechanisms of the polymeric chains which it is in compliance to the literature. (author)

  3. Suspension-firing of wood with coal ash addition: Probe measurements of ash deposit build-up at Avedøre Power Plant (AVV2)

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Jappe Frandsen, Flemming

    This report is about full-scale probe measurements of deposit build-up and removal conducted at the Avedøreværket Unit 2, a 800 MWth suspension boiler, firing wood and natural gas with the addition of coal ash. Coal ash was used as an additive to capture potassium (K) from wood-firing. Investigat......This report is about full-scale probe measurements of deposit build-up and removal conducted at the Avedøreværket Unit 2, a 800 MWth suspension boiler, firing wood and natural gas with the addition of coal ash. Coal ash was used as an additive to capture potassium (K) from wood......-firing. Investigations of deposit formation rate were made by use of an advanced online ash deposition/shedding probe. Quantification of ash deposition and shedding was made via deposit mass uptake signals obtained from the deposit probe. The influence of coal ash, flue gas temperature, probe surface temperature...... and boiler load on ash deposition propensity was investigated. Results of ash deposition propensity showed increasing trend with increasing flue gas temperature. Video monitoring revealed that the deposits formed were not sticky and could be easily removed, and even at very high flue gas temperatures (> 1350...

  4. Evaluasi karakteristik abu sekam padi dengan kitosan molekul tinggi nanopartikel sebagai bahan dentinogenesis (Characteristic evaluation of rice husk ash with chitosan high molecule nanoparticle as dentinogenesis material

    Directory of Open Access Journals (Sweden)

    Pretty Farida Sinta Silalahi

    2014-06-01

    Full Text Available Background: Mineral trioxide aggregate (MTA and resin modified glass ionomer cement (RMGIC are the material used for indirect and direct pulp capping due to biocompatibility, but these materials have many shortcomings. Mineral trioxide aggregate contains a little amount of arsenic and has long setting time, while HEMA containing RMGIC are cytotoxic. Rice husk ash nanoparticles (RHAn is a potential source of silica. High molecular chitosan nanoparticles (HMCn can stimulate the formation of reparative dentin. Combination of these two materials is biocompatible and have good sealing ability. Purpose: This study was aimed to study RHAn + HMCn used as biomaterials for prevention of pulpodentinal complex by examined at the microstructure of dentin surfaces applied with RHAn + HMCn. Methods: Twenty-four mandibular premolar teeth extracted for orthodontic purposes, were made cavity class I preparation with 3 mm depth above the cemento-enamel junction (CEJ. Then each tooth was cut in bucco-lingual direction and each part was cut using a cervical disc bur. Samples were divided into 3 groups, group I the teeth were applied with MTA; group II the teeth were applied RMGIC; group III the teeth were apllied with RHAn + HMCn. Characterization was done by using Scanning Electron Microscopy (SEM on the interface between test material and dentin adjacent to the pulp to see surface microstructure. Results: Material microstructure of RHAn + HMCn applied to the dentine showed tags like structure which was more significant than MTA. RHAn + HMCn showed to have better sealing ability than MTA. Porosity of ASPn + HMCn was less than MTA and RMGIC. Conclusion: The study suggested that the combined RHAn + HMCn biomaterials could be used as an active biomaterial that can maintain the integrity of pulp dentinal complex.Latar belakang: Mineral trioksida agregat (MTA dan semen ionomer kaca modifikasi resin (SIKMR adalah bahan yang digunakan untuk pulp capping langsung dan tidak

  5. Caracterização de cinza de casca de arroz para uso como matéria-prima na fabricação de refratários de sílica Characterization of rice husk ash for use as raw material in the manufacture of silica refractory

    Directory of Open Access Journals (Sweden)

    Viviana Possamai Della

    2001-12-01

    Full Text Available The characterization of rice husk ash, a deriving by-product of the burning of the rice husk during the rice processing is the object of this study. This by-product, for being rich in silica, can be an important raw material for the production of siliceous ceramics, such as thermal insulators and refractory. A combination of surface analysis, thermal analysis and microscopy analysis techniques was used for the characterization. The characterized by-product presented as main component the silica, under amorphous form, with a maximum content of alkalis around 1%, features that become it potentially interesting for the production of ceramic materials.

  6. effect of neem seed husk ash em seed husk ash em seed husk ash ...

    African Journals Online (AJOL)

    User

    a much sought after opportunity to mitigate tod waste management problems. Even if this is don small amounts, high production rates will trans into significant consumption of waste materials a for the industry willing to use them, the latter constitute a cheap and renewable source of materials [1].Therefore utilization of.

  7. Full-scale ash deposition measurements at Avedøre Power Plant unit 2 during suspension-firing of wood with and without coal ash addition

    DEFF Research Database (Denmark)

    Wu, Hao; Shafique Bashir, Muhammad; Jensen, Peter Arendt

    addition on deposit formation during wood suspension-firing at AVV2 was evaluated. It was revealed that the addition of coal fly ash could significantly influence the ash deposition/shedding behaviors and the deposit properties. The effect was evident at both measurement locations. At the location......The formation of deposits during suspension-firing of wood at Avedøre Power Plant unit 2 (AVV2) was studied by using an advanced deposit probe system. The tests were conducted both with and without coal ash addition, and at two different locations with flue gas temperatures of 1250-1300 oC and 750...

  8. Use of heterogeneous CaO and SnO{sub 2} catalysts supported on rice husk ash to produce biodiesel; Emprego de catalisadores heterogeneos de CaO e SnO{sub 2} suportados em cinza de casca de arroz na obtencao de biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Ana Brigida [Instituto Federal do Espirito Santo, Vitoria, ES (Brazil); Silva, Paulo Roberto Nagipe da; Stumbo, Alexandre Moura, E-mail: nagipe@uenf.br [Laboratorio de Ciencias Quimicas, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ (Brazil); Freitas, Jair C.C. [Departamento de Fisica, Centro de Ciencias Exatas, Universidade Federal do Espirito Santo, Vitoria, ES (Brazil)

    2012-07-01

    Silica obtained from rice husk after acid leaching and calcination was compared to commercial silica as a catalyst support. CaO and SnO{sub 2} catalysts were prepared by impregnation and tested in the transesterification of soybean oil and the esterification of oleic acid. CaO catalysts showed basic character and were the most active for transesterification, whereas SnO{sub 2} catalysts were acid and the most effective for esterification. In both cases the performances of the catalysts prepared with rice husk ash and commercial silica were similar. These results demonstrate that rice husk is a cost-effective and environmentally-friendly source of silica that can be used as a catalyst support. (author)

  9. Sinabung Volcanic Ash Utilization As The Additive for Paving Block Quality A and B

    Science.gov (United States)

    Sembiring, I. S.; Hastuty, I. P.

    2017-03-01

    Paving block is one of the building materials used as the top layer of the road structure besides asphalt and concrete. Paving block is made of mixed materials such as portland cement or other adhesive materials, water and aggregate. In this research, the material used as the additive of cement and concrete is volcanic ash from Mount Sinabung, it is based on the results of the material testing, Sinabung ash contains 74.3% silica (SiO2). The purpose of this research aims to analyze the behavior of the paving blocks quality A and B with and without a mixture of Sinabung ash, to analyze the workability of fresh concrete using Sinabung ash as an additive in concrete, and to compare the test results of paving blocks with and without using Sinabung ash. The samples that we made consist of four variations of the concrete mix to experiment a mixture of normal sample without additive, samples which are mixed with the addition of Sinabung ash 5%, 10%, 15%, 20% and 25% of the volume of concrete/m3. Each variation consists of 10 samples of the concrete with 28 days curing time period. We will do the compressive strength and water absorption test to the samples to determine whether the samples are in accordance with the type needed. According to the test result, paving blocks with Sinabung ash and curing time reach quality A at 0%, 5% and 10% mixture with the compressive strength of each 50.14 MPa, 46.20 MPa and 1.49Mpa, and reach quality B at 15%, 20 %,25% mixture with curing time and 0%, 5%, 10%, 15%, 20% and 25% mixture without curing time. According to the absorption values we got from the test which are 6.66%, 6.73%, 6.88%, 7.03%, 7.09% and 7.16%, the entire sample have average absorption exceeding SNI standardization which is above 6% and reach quality C. Based on compressive strength and absorption data obtained Sinabung ash can’t fully replace cement as the binder because of the low CaO content.

  10. Effect of additional materials on the properties of glass-ceramic produced from incinerator fly ashes.

    Science.gov (United States)

    Cheng, T W

    2004-07-01

    There are 21 Metro-waste incinerators in Taiwan under construction and are expected to be finished at year 2003. It is estimated that these incinerators will produce about two million tons of incinerator ash. In order to reduce the volume and eliminate contamination problems, high temperature molten technology studies have been conducted. The purpose of this research was that of trying to control the chemical composition of the glass-ceramic produced from incinerator fly ash, in order to improve the characteristics of the glass-ceramic. The experimental results showed that the additional materials, Mg(OH)2 and waste glass cullet, can change glass-ceramic phases from gehlenite to augite, pigeonite, and diopside. The physical, mechanical and chemical resistance properties of the glass-ceramic also showed much better characteristics than prepared glass-ceramic using incinerator fly ash alone.

  11. Improved Reactivity of Fly Ash-Slag Geopolymer by the Addition of Silica Fume

    Directory of Open Access Journals (Sweden)

    N. K. Lee

    2016-01-01

    Full Text Available This study investigates the improved reactivity of a geopolymer based on a combination of fly ash and blast furnace slag (BFS by the addition of silica fume. The geopolymer was synthesized by activating a mixture of fly ash, BFS, and three different types of silica fume with alkali activator. X-ray diffraction (XRD and inductively coupled plasma-optical emission spectroscopy (ICP-OES were utilized to characterize the reaction. The silicate structure was also analyzed by nuclear magnetic resonance (NMR spectroscopy. From these results, it was found that the replacement of fly ash with the silica fume led to a significant decrease in the Q4(1Al and an increase in the Q4(2Al, Q4(3Al, and Q4(4Al. The Si/Al ratio of the aluminosilicate gel was relatively constant, ranging from 2.0 to 2.6, while the Si/Al ratio of the C-S-H gel increased with the addition of silica fume. Therefore, some of the Al dissolved from the slag contributed to the formation of aluminosilicate gel, and the remnant slag particles mostly participated in the formation of the C-(A-S-H gel with a decrease in the Q2(1Al. The increase in the reactivity of slag caused by the addition of silica fume was attributed to the reaction of the Al in the slag with the silica fume.

  12. The effects of different types of nano-silicon dioxide additives on the properties of sludge ash mortar.

    Science.gov (United States)

    Luo, Huan-Lin; Chang, Wei-Che; Lin, Deng-Fong

    2009-04-01

    To improve the drawbacks caused by the sludge ash replacement in mortar, the previous studies have shown that the early strength and durability of sludge ash/cement mortar are improved by adding nano-silicon dioxide (nano-SiO2) to mortar. In this article, three types of nano-SiO2--SS, HS, and SP (manufacturer code names)--were applied to sludge ash/cement mixture to make paste or mortar specimens. The object is to further extend the recycle of the sludge ash by determining the better type of nano-SiO2 additive to improve properties of sludge ash/ cement paste or mortar. The cement was replaced by 0, 10, 20, and 30% of sludge ash, and 0 and 2% of nano-SiO2 additives were added to the sludge ash paste or mortar specimens. Tests such as setting time, compressive strength, scanning electron microscopy, X-ray diffraction, nuclear magnetic resonance, and thermogravimetric analysis/differential thermal analysis were performed in this study. Test results show that nano-SiO2 additives can not only effectively increase the hydration product (calcium silicate hydrate [C-S-H] gel), but also make the crystal structure denser. Among the three types of nano-SiO2 additive, the SS type can best improve the properties of sludge ash/cement paste or mortar, followed by the SP and HS types.

  13. Alkali-activated fly ash-based geopolymers with zeolite or bentonite as additives

    Energy Technology Data Exchange (ETDEWEB)

    Mingyu Hu; Xiaomin Zhu; Fumei Long [Nanchang University, Nanchang (China). College of Civil Engineering

    2009-11-15

    Geopolymers were synthesized by using fly ash as the main starting material, zeolite or bentonite as supplementary materials, and NaOH and CaO together as activator. An orthogonal array testing protocol was used to analyze the influence of the mix proportion on the properties of the geopolymers. The results indicate that the concentration of NaOH solution and the CaO content play an important role on the strength of the materials. Especially, with zeolite as additive, the fly ash-based geopolymer shows the highest strength and the best sulfate resistance. Infrared spectroscopy, X-ray, and SEM-EDX demonstrate that supplementary zeolite may involve the process of geopolymerization to form a stable zeolitic structure and improve the properties of the geopolymer. Bentonite simply acts as a filler to make the geopolymer more compact, but shows no improvement on the compositions and the microstructures of the geopolymer.

  14. Cementing Material From Rice Husk-Broken Bricks-Spent Bleaching Earth-Dried Calcium Carbide Residue

    OpenAIRE

    Muthengia Jackson Washira

    2012-01-01

    A cementious material, coded CSBR (Carbide residue Spent bleaching earth Broken bricks and Rice husks), was made from dried calcium carbide residue (DCCR) and an incinerated mix of rice husks (RH), broken bricks (BB) and spent bleaching earth (SBE). Another material, coded SBR (Spent bleaching earth Broken bricks and Rice husk ash), was made from mixing separately incinerated RH, SBE and ground BB in the same ash ratio as in CSBR. When CSBR was inter-ground with Ordinary Portland Cement (OPC)...

  15. The effect of slag addition on strength development of Class C fly ash geopolymer concrete at normal temperature

    Science.gov (United States)

    Wardhono, Arie; Law, David W.; Sutikno, Dani, Hasan

    2017-09-01

    This paper presents the effect of slag addition on strength development and workability of fly ash/slag based geopolymer (FASLG) concrete cured at normal temperature. Class C fly ash with high ferrite (Fe) content was used as the primary material. The proportions of fly ash (FA) to slag (SL) are: 1 FA : 0 SL, 0.9 FA : 0.1 SL, 0.7 FA : 0.3 SL, and 0.5 FA : 0.5 SL. The workability and strength properties were determined by slump, vikat, and compressive strength tests. The result shows that the highest compressive strength was achieved by FASLG-3 concrete with 30% slag addition and exhibited a comparable strength to that normal concrete at 28 days. The 30% slag addition also improve the workability and increase the setting time of FASLG concrete specimens. It can be concluded that the slag inclusion on fly ash will improve the performance of geopolymer concrete at normal temperature.

  16. Properties of high calcium fly ash geopolymer pastes with Portland cement as an additive

    Science.gov (United States)

    Phoo-ngernkham, Tanakorn; Chindaprasirt, Prinya; Sata, Vanchai; Pangdaeng, Saengsuree; Sinsiri, Theerawat

    2013-02-01

    The effect of Portland cement (OPC) addition on the properties of high calcium fly ash geopolymer pastes was investigated in the paper. OPC partially replaced fly ash (FA) at the dosages of 0, 5%, 10%, and 15% by mass of binder. Sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) solutions were used as the liquid portion in the mixture: NaOH 10 mol/L, Na2SiO3/NaOH with a mass ratio of 2.0, and alkaline liquid/binder (L/B) with a mass ratio of 0.6. The curing at 60°C for 24 h was used to accelerate the geopolymerization. The setting time of all fresh pastes, porosity, and compressive strength of the pastes at the stages of 1, 7, 28, and 90 d were tested. The elastic modulus and strain capacity of the pastes at the stage of 7 d were determined. It is revealed that the use of OPC as an additive to replace part of FA results in the decreases in the setting time, porosity, and strain capacity of the paste specimens, while the compressive strength and elastic modulus seem to increase.

  17. Superplasticizer Addition to Carbon Fly Ash Geopolymers Activated at Room Temperature.

    Science.gov (United States)

    Carabba, Lorenza; Manzi, Stefania; Bignozzi, Maria Chiara

    2016-07-18

    Present concerns about global warming due to the greenhouse emissions in the atmosphere have pushed the cement industry to research alternatives to ordinary Portland cement (OPC). Geopolymer binder may constitute a possible breakthrough in the development of sustainable materials: understanding the effectiveness and the influences of superplasticizers on geopolymer systems is one of the essential requirements for its large-scale implementation. This study aims to investigate the possibility of using commercially available chemical admixtures designed for OPC concrete, to improve fresh properties of fly ash-based geopolymers and mortars. A special emphasis is laid upon evaluating their influence on mechanical and microstructural characteristics of the hardened material realized under room-temperature curing conditions. Results indicate that the addition of a polycarboxylic ether-based superplasticizer, in the amount of 1.0 wt. % by mass of fly ash, promotes an improvement in workability without compromising the final strength of the hardened material. Moreover, the addition of the polycarboxylic ether- and acrylic-based superplasticizers induces a refinement in the pore structure of hardened mortar leading to a longer water saturation time.

  18. Superplasticizer Addition to Carbon Fly Ash Geopolymers Activated at Room Temperature

    Directory of Open Access Journals (Sweden)

    Lorenza Carabba

    2016-07-01

    Full Text Available Present concerns about global warming due to the greenhouse emissions in the atmosphere have pushed the cement industry to research alternatives to ordinary Portland cement (OPC. Geopolymer binder may constitute a possible breakthrough in the development of sustainable materials: understanding the effectiveness and the influences of superplasticizers on geopolymer systems is one of the essential requirements for its large-scale implementation. This study aims to investigate the possibility of using commercially available chemical admixtures designed for OPC concrete, to improve fresh properties of fly ash-based geopolymers and mortars. A special emphasis is laid upon evaluating their influence on mechanical and microstructural characteristics of the hardened material realized under room-temperature curing conditions. Results indicate that the addition of a polycarboxylic ether-based superplasticizer, in the amount of 1.0 wt. % by mass of fly ash, promotes an improvement in workability without compromising the final strength of the hardened material. Moreover, the addition of the polycarboxylic ether- and acrylic-based superplasticizers induces a refinement in the pore structure of hardened mortar leading to a longer water saturation time.

  19. Biomass ash reutilisation as an additive in the composting process of organic fraction of municipal solid waste.

    Science.gov (United States)

    Asquer, Carla; Cappai, Giovanna; De Gioannis, Giorgia; Muntoni, Aldo; Piredda, Martina; Spiga, Daniela

    2017-11-01

    In this work the effects of selected types of biomass ash on the composting process and final product quality were studied by conducting a 96-day long experiment where the source separated organic fraction of municipal waste, mixed with wood prunings that served as bulking agent, was added with 0%, 2%, 4% and 8% wt/wt of biomass ash. The evolution over time of the main process parameters was observed, and the final composts were characterised. On the basis of the results, both the composting process and the quality of the final product were improved by ash addition. Enhanced volatile solids reduction and biological stability (up to 32% and 52%, respectively, as compared to the unamended product) were attained when ash was added, since ash favored the aerobic degradation by acting asa physical conditioner. In the final products, higher humification of organic matter (expressed in terms of the humification index, that was 2.25 times higher in the most-enriched compost than in the unamended one) and total Ca, K, Mg and P content were observed when ash was used. The latter aspect may influence the composts marketability positively, particularly with regards to potassium and phosphorus. The heavy metals content, that is regarded as the main environmental disadvantage when using ash asa composting additive, did not negatively affect the final composts quality. However, some other controversial effects of ash, related to the moisture and temperature values attained during the process, pH (8.8-9.2 as compared to 8.2 of the unamended compost) and electrical conductivity levels (up to 53% higher as compared to the unamended compost) in the final composts, were also observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    Science.gov (United States)

    Palaniappan, Jayanthi

    2017-04-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  1. UTILIZATION OF HAZELNUT HUSKS, TEA AND TOBACCO WASTES, AS RAW MATERIALS

    Directory of Open Access Journals (Sweden)

    Ş. İsmail KIRBAŞLAR

    2001-01-01

    Full Text Available In this study, moisture, ash, oil and cellulose of hazelnut husks, tea and tobacco wastes were analyzed. The amounts of pentosan, pentose and furfural were determined in the hazelnut husks, tea and tobacco wastes. Furfural was produced from each three waste products by a steam distillation method. IR spectra of each furfural product were measured and compared with standard furfural. Activated carbon prepared from the hazelnut husks at the different temperature, and organic and inorganic pollutants were removed by using the adsorbent obtained from hazelnut husk.

  2. [Husk of Venezuelan cocoa as raw material of infusions].

    Science.gov (United States)

    Sangronis, Elba; José Soto, María; Valero, Yolmar; Buscema, Ignacio

    2014-06-01

    In the cocoa bean industry, some by-products go underutilized. Some of these components could provide other innovative products, and such is the case with the husk of the cocoa bean. Previous studies have attributed the husk with a high antioxidant capacity, which added to its relative low cost, makes it an attractive ingredient for the production of infusions. However, prior to promoting it as such, its quality needs to be guaranteed. This study evaluated the chemical composition of the husk of cocoa, its microbiologic quality and other parameters in order to be considered raw material in the preparation of infusions. The cocoa was cultivated in two different states in Venezuela. Moisture, protein, fat, ash, carbohydrates, microbiologic quality and ochratoxin A as well antioxidant properties, content of foreign matter, insoluble ash in HCL and aqueous extract were evaluated in the husk of cocoa seeds. Applied methods were in compliance with national and international norms. Significant differences were determined between the samples through the ANOVA application. A low level in moisture content, but high in ash, along with a microbiologic quality that met the norm, and an absence of ochratoxin A were observed in the totality of the analyzed samples. Low levels of foreign matter, the high value of its aqueous extract and high phenolic compounds content with antioxidant activity allow for the recommendation of the husk of cocoa as raw material for the preparation of infusions.

  3. Enhancement of mercury capture by the simultaneous addition of hydrogen bromide (HBr) and fly ashes in a slipstream facility.

    Science.gov (United States)

    Cao, Yan; Wang, Quan-Hai; Li, Jun; Cheng, Jen-Chieh; Chan, Chia-Chun; Cohron, Marten; Pan, Wei-Ping

    2009-04-15

    Low halogen content in tested Powder River Basin (PRB) coals and low loss of ignition content (LOI) in PRB-derived fly ash were likely responsible for higher elemental mercury content (averaging about 75%) in the flue gas and also lower mercury capture efficiency by electrostatic precipitator (ESP) and wet-FGD. To develop a cost-effective approach to mercury capture in a full-scale coal-fired utility boiler burning PRB coal, experiments were conducted adding hydrogen bromide (HBr) or simultaneously adding HBr and selected fly ashes in a slipstream reactor (0.152 x 0.152 m) under real flue gas conditions. The residence time of the flue gas inside the reactorwas about 1.4 s. The average temperature of the slipstream reactor was controlled at about 155 degrees C. Tests were organized into two phases. In Phase 1, only HBr was added to the slipstream reactor, and in Phase 2, HBr and selected fly ash were added simultaneously. HBr injection was effective (>90%) for mercury oxidation at a low temperature (155 degrees C) with an HBr addition concentration of about 4 ppm in the flue gas. Additionally, injected HBr enhanced mercury capture by PRB fly ash in the low-temperature range. The mercury capture efficiency, attesting conditions of the slipstream reactor, reached about 50% at an HBr injection concentration of 4 ppm in the flue gas. Compared to only the addition of HBr, simultaneously adding bituminous-derived fly ash in a minimum amount (30 lb/MMacf), together with HBr injection at 4 ppm, could increase mercury capture efficiency by 30%. Injection of lignite-derived fly ash at 30 lb/MMacf could achieve even higher mercury removal efficiency (an additional 35% mercury capture efficiency compared to HBr addition alone).

  4. EKSTRAKSI SELULOSA DARI POD HUSK KAKAO MENGGUNAKAN SODIUM HIDROKSIDA

    Directory of Open Access Journals (Sweden)

    Gatot Siswo Hutomo

    2013-03-01

    sodium bisulÞ t 3% (reductor to rise lightness. FT-IRand X-Ray spectra were detected in cellulose. Cellulose extracted using sodium hydroxide from pod husk cacao about26.09% (db with crystalline 27.14%, ash content 6.56% (db, WHC 5.87 g/g and OHC 2.74 g/g. It could be concludedthat sodium hydroxide 12% is the best level to extract cellulose from pod husk cacao with double bleaching.Keywords: Cellulose, pod husk, cacao, extraction

  5. Microstructure and tensile properties of various varieties of rice husk.

    Science.gov (United States)

    Chen, Ziyong; Xu, Yangzi; Shivkumar, Satya

    2017-07-19

    Rice husk is a complex hierarchical assembly of hollow fibers consisting of cellulose, hemicellulose and lignin. In addition, it can also contain pectin and significant amounts of silica. Rice husk can be used in diverse applications and generally in the form of rice husk powder. This study aimed to investigate the structural features and mechanical properties of various varieties of whole rice husks. Rice husk consists of three sections: epidermis, sub-hypodermis and hypodermis. The thickness of these layers, the diameters of the hollow fibers and the wall thickness vary with the variety of rice husk. The elastic modulus is typically between 0.3 and 2.6 GPa, and the ultimate tensile strength varies from 19 to 135 MPa depending on the variety of rice husk. Rice husk has a unique hierarchical structure in which the fibers exhibit a staggered perpendicular arrangement and the entire fiber sections are covered by an external shell. The tensile properties vary with the variety of rice husk. The wide range in these tensile properties may be attributed to the size and orientation of the fibers. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  6. Improved cement mortars by addition of carbonated fly ash from solid waste incinerators

    Directory of Open Access Journals (Sweden)

    López-Zaldívar, O.

    2015-09-01

    Full Text Available This article presents the results of a research developing high performance cement mortars with the addition of municipal solid waste incineration fly ash (MSWIFA stabilized as insoluble carbonates. The encapsulation of hazardous wastes in mortar matrixes has also been achieved. The ashes present high concentrations of chlorides, Zn and Pb. A stabilization process with NaHCO3 has been developed reducing 99% the content of chlorides. Developed mortars replace 10% per weight of the aggregates by treated MSWIFA. Physical/mechanical properties of these mortars have been studied. Presence of Zn, Pb, Cu and Cd has been also analyzed confirming that leaching of these heavy metal ions is mitigated. Conclusions prove better behavior of CAC and CSA mortars than those of CEM-I and CEM-II cement. Results are remarkable for the CAC mortars, improving reference strengths in more than 25%, which make them a fast-curing product suitable for the repair of structures or industrial pavements.Este artículo presenta los resultados del desarrollo de morteros mejorados con la incorporación de cenizas volantes de residuos sólidos urbanos inertizadas en forma de carbonatos. Además se consigue la encapsulación de un residuo peligroso. Las cenizas presentan una alta concentración de cloruros, Zn y Pb. Se ha desarrollado un proceso de estabilización con NaHCO3 reduciendo en un 99% el contenido de cloruros. Los morteros reemplazan un 10% en peso del árido por cenizas tratadas. Se han analizado sus propiedades físico/mecánicas y la presencia de Zn, Pb, Cu y Cd. Se demuestra un mejor comportamiento de los morteros de CAC y CSA que los de CEM-I y CEM-II y se mitiga el lixiviado de metales pesados. Los resultados son significativos en los morteros CAC al mejorar las resistencias de los de referencia en un 25%. Los morteros desarrollados son de curado rápido adecuados para la reparación de estructuras o soleras industriales.

  7. Solidification/stabilization of fly ash from city refuse incinerator facility and heavy metal sludge with cement additives.

    Science.gov (United States)

    Cerbo, Atlas Adonis V; Ballesteros, Florencio; Chen, Teng Chien; Lu, Ming-Chun

    2017-01-01

    Solidification and stabilization are well-known technologies used for treating hazardous waste. These technologies that use cementitious binder have been applied for decades as a final treatment procedure prior to the hazardous waste disposal. In the present work, hazardous waste like fly ash containing high concentrations of heavy metals such Zn (4715.56 mg/kg), Pb (1300.56 mg/kg), and Cu (534.72 mg/kg) and amounts of Ag, Cd, Co, Cr, Mn, and Ni was sampled from a city refuse incinerator facility. This fly ash was utilized in the solidification/stabilization of heavy metal sludge since fly ash has cement-like characteristics. Cement additives such as sodium sulfate, sodium carbonate, and ethylenediaminetetraacetic acid (EDTA) was incorporated to the solidified matrix in order to determine its effect on the solidification/stabilization performance. The solidified matrix was cured for 7, 14, 21, and 28 days prior for its physical and chemical characterizations. The results show that the solidified matrix containing 40% fly ash and 60% cement with heavy metal sludge was the formulation that has the highest fly ash content with a satisfactory strength. The solidified matrix was also able to immobilize the heavy metals both found in the fly ash and sludge based on the toxicity characteristic leaching procedure (TCLP) test. It also shows that the incorporation of sodium carbonate into the solidified matrix not only further improved the compressive strength from 0.36 MPa (without Na2CO3) to 0.54 MPa (with Na2CO3) but also increased its leaching resistance.

  8. Effects of micro-nano and non micro-nano MSWI ashes addition on MSW anaerobic digestion.

    Science.gov (United States)

    Lo, H M; Chiu, H Y; Lo, S W; Lo, F C

    2012-06-01

    This study aims at investigating the effects of micro-nano municipal solid waste (MSW) incinerator (MSWI) fly ash (FA) and bottom ash (BA) on the MSW anaerobic digestion. Results showed that suitable micro-nano and non micro-nano MSWI ashes addition (FA/MSW 3, 6, 18 and 30 g g(-1) VS and BA/MSW 12, 36, 60 and 120 g g(-1) VS) could enhance the biogas production compared to the control. It was particularly found to have the highest biogas production at the micro-nano MSWI BA/MSW ratio of 36 g g(-1) VS (∼193 mL g(-1) VS MSW, ∼3.5 times to the control). Micro-nano MSWI FA and BA added bioreactors had the higher biogas production than the corresponding non micro-nano MSWI FA and BA added ones. Suitable MSWI ashes addition could improve the biogas production due to the released metals levels suitable for the MSW anaerobic digestion particularly found in the micro-nano added bioreactors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Application of Anova on Fly Ash Leaching Kinetics for Value Addition

    Science.gov (United States)

    Swain, Ranjita; Mohapatro, Rudra Narayana; Bhima Rao, Raghupatruni

    2016-04-01

    Fly ash is a major problem in power plant sectors as it is dumped at the plant site. Fly ash generation increases day to day due to rapid growth of steel industries. Ceramic/refractory industries are growing rapidly because of more number of steel industries. The natural resources of the ceramic/refractory raw materials are depleting with time due to its consumption. In view of this, fly ash from thermal power plant has been identified for use in the ceramic/refractory industries after suitable beneficiation. In this paper, sample was collected from the ash pond of Vedanta. Particle size (d80 passing size) of the sample is around 150 micron. The chemical analysis of the sample shows that 3.9 % of Fe2O3 and CaO is more than 10 %. XRD patterns show that the fly ash samples consist predominantly of the crystalline phases of quartz, hematite and magnetite in a matrix of aluminosilicate glass. Leaching of iron oxide is 98.3 % at 3 M HCl concentration at 90 °C for 270 min of leaching time. Kinetic study on leaching experiment was carried out. ANOVA software is utilized for curve fitting and the process is optimized using MATLAB 7.1. The detailed study of properties for ceramic material is compared with the standard ceramic materials. The product contains 0.3 % of iron. The other properties of the product have established the fact that the product obtained can be a raw material for ceramic industries.

  10. The effects of the sequential addition of synthesis parameters on the performance of alkali activated fly ash mortar

    Directory of Open Access Journals (Sweden)

    Jean-Baptiste Mawulé Dassekpo

    Full Text Available Geopolymer is an energy efficient and sustainable material that is currently used in construction industry as an alternative for Portland cement. As a new material, specific mix design method is essential and efforts have been made to develop a mix design procedure with the main focus on achieving better compressive strength and economy. In this paper, a sequential addition of synthesis parameters such as fly ash-sand, alkaline liquids, plasticizer and additional water at well-defined time intervals was investigated. A total of 4 mix procedures were used to study the compressive performance on fly ash-based geopolymer mortar and the results of each method were analyzed and discussed. Experimental results show that the sequential addition of sodium hydroxide (NaOH, sodium silicate (Na2SiO3, plasticizer (PL, followed by adding water (WA increases considerably the compressive strengths of the geopolymer-based mortar. These results clearly demonstrate the high significant influence of sequential addition of synthesis parameters on geopolymer materials compressive properties, and also provide a new mixing method for the preparation of geopolymer paste, mortar and concrete. Keywords: Mixing method, Sequential addition, Synthesis parameters, Fly ash-based geopolymer mortar, Compressive properties

  11. 76 FR 5679 - Emerald Ash Borer; Addition of Quarantined Areas in Kentucky, Michigan, Minnesota, New York...

    Science.gov (United States)

    2011-02-02

    .... Although EAB adults have been known to fly as much as one-half mile from one tree to the next, the pest can.... Ash trees are valuable to the commercial timber industry and are commonly planted in urban areas. In... Budget has waived its review under Executive Order 12866. Regulatory Flexibility Act This action affirms...

  12. The Effect of Silane Addition on Chitosan-Fly Ash/CTAB as Electrolyte Membrane

    Science.gov (United States)

    Kusumastuti, E.; Isnaeni, D.; Sulistyaningsih, T.; Mahatmanti, F. W.; Jumaeri; Atmaja, L.; Widiastuti, N.

    2017-02-01

    Electrolyte membrane is an important component in fuel cell system, because it may influence fuel cell performance. Many efforts have been done to produce electrolyte membrane to replace comercial membrane. In this research, electrolyte membrane is composed of chitosan as an organic matrix and fly ash modified with CTAB and silane as inorganic filler. Fly ash is modified using silane as coupling agent to improve interfacial morphology between organic matrix and inorganic filler. This research aims to determine the best membrane performance based on its characteristics such as water uptake, mechanical properties, proton conductivity, and methanol permeability. The steps that have been done include silica preparation from fly ash, modification of silica surface with CTAB, silica coupling process with silane, synthesis of membranes with inversion phase method, and membrane characterization. The result shows that membrane C-FA/CTAB-Silane 10% (w/w) has the best performance with proton conductivity 8.00 x 10-4 S.cm-1, methanol permeability 3.37 x 10-7 cm.s-1, and selectivity 2.12 x 103 S.s.cm-3. The result of FTIR analysis on membrane C-FA/CTAB-Silane 10% shows that there is only physical interaction occured between chitosan, fly ash and silane, because there is no peak differences significantly at wave number 1000-1250 cm-1, while morphology analysis on membrane with Scanning Electron Microscopy (SEM) shows good dispersion and there is no agglomeration on chitosan matrix.

  13. Effect of curing conditions and ionic additives on properties of fly ash ...

    Indian Academy of Sciences (India)

    In the present work the reaction between fly ash and lime in fly ash–lime compacts under water curing and steam curing conditions was studied thoroughly in ... and Materials Engineering Department, College of Engineering and Computing, Florida International University, Miami, Fl 33174, USA; Chemical Engineering ...

  14. Corrosion of Modified Concrete with Sugar Cane Bagasse Ash

    Directory of Open Access Journals (Sweden)

    R. E. Núñez-Jaquez

    2012-01-01

    Full Text Available Concrete is a porous material and the ingress of water, oxygen, and aggressive ions, such as chlorides, can cause the passive layer on reinforced steel to break down. Additives, such as fly ash, microsilica, rice husk ash, and cane sugar bagasse ash, have a size breakdown that allows the reduction of concrete pore size and, consequently, may reduce the corrosion process. The objective of this work is to determine the corrosion rate of steel in reinforced concrete by the addition of 20% sugar cane bagasse ash by weight of cement. Six prismatic specimens (7×7×10 cm with an embedded steel rod were prepared. Three contained 20% sugar cane bagasse ash by weight of cement and the other three did not. All specimens were placed in a 3.5% NaCl solution and the corrosion rate was determined using polarization resistance. The results showed that reinforced concrete containing sugar cane bagasse ash has the lowest corrosion rates in comparison to reinforced concrete without the additive.

  15. Effects of kaolin-additions in combustion of wood fuels on hardening and leaching properties of ash; Paaverkan av kaolintillsats vid foerbraenning av biobraensle paa askans haerdnings- och lakningsegenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Steenari, Britt-Marie; Karlfeldt, Karin (Dept. of Chemical And Biological Engineering, Chalmers Univ. of Technology, SE-412 96 Goeteborg (Sweden)). e-mail: bms@chalmers.se

    2007-06-15

    In several investigations it has been shown that kaolin works well as an anti-agglomerating and anti-ash sintering agent in combustion of bio-fuels with a potassium rich ash in fluidised bed boilers. Combustion tests have shown that the kaolin addition may result in an ash melting temperature that is a couple of hundred degrees centigrade higher than for the original ash. This way the kaolin hinders the fouling of super heater surfaces by sticky ash. Many boiler owners treat their wood fuel ash with the aim to recycle it to forest soil as a nutrient source and acid neutralising agent. Therefore it was considered important to investigate if an addition of kaolin in the boiler would have a negative influence on the ash leaching properties. Thus, the aim of the project was to investigate the hardening reactions and leaching properties of normal wood ash and wood ash produced with addition of kaolin. The ash samples were produced in the same boiler and in similar combustion conditions. It was especially interesting to study if the ash would contain soluble aluminium due to the kaolin addition since aluminium in solution may have negative effects on the eco system. The results showed that an important difference between the normal fly ash and the fly ash with kaolin was that the release of potassium i leaching was decreased due to the kaolin addition, especially at high pH levels. This is positive, since potassium normally is released very fast in the forest. In addition, the kaolin containing ash has a faster initial setting/hardening process than the normal ash. The structure of the hardened ash particles is also more durable than that of the normal ash. This is also a positive effect since it indicates that it could be possible to handle the hardened ash after a shorter storage period. However, it has not been investigated if this effect remains in large scale operation and in a longer time perspective. The acid neutralising capacity of fly ash with kaolin is

  16. Proximate Composition, Extraction, and Purification of Theobromine from Cacao Pod Husk (Theobroma Cacao L.)

    OpenAIRE

    Van Tang Nguyen; Nghia Huu Nguyen

    2017-01-01

    The aims of this study were to determine the proximate composition of cacao pod husk as well as the optimal conditions for extraction and purification of theobromine from cacao pod husk. The results indicated that cacao pod husk had high contents of moisture and carbohydrate (87.06% and 11.03% by fresh weight, respectively), but low contents of crude protein, crude lipid, and ash (0.31%, 0.12%, and 1.48% by fresh weight, respectively). The optimal conditions for extraction of theobromine from...

  17. A Highly Selective Photoresist Ashing Process for Silicon Nitride Films by Addition of Trifluoromethane

    Science.gov (United States)

    Saito, Makoto; Eto, Hideo; Makino, Nobuaki; Omiya, Kayoko; Homma, Tetsuya; Nagatomo, Takao

    2001-09-01

    A highly selective photoresist ashing process was developed for the fabrication of thin-film transistor liquid-crystal displays (TFT-LCDs). This ashing process utilizes downflow plasma consisting of a carbon trifluoromethane/oxygen (CHF3/O2) gas mixture at a low temperature. The etching selectivity of photoresist films to silicon nitride (SiN) film increased when using the CHF3/O2 gas mixture plasma, as compared to that when using the carbon tetrafluoride/oxygen (CF4/O2) gas mixture plasma. At the CHF3 gas flow rate of 30 sccm, a high etching selectivity ratio of about 1080 for the photoresist films to the SiN films was achieved at room temperature. On the basis of surface analysis results for SiN films and plasma analysis results for the CHF3/O2 gas mixture, a mechanism for the high etching selectivity of the photoresist films was proposed. Reaction products that were formed on SiN films by the CHF3/O2 gas mixture plasma obstructed the etching of SiN films by fluorine (F) radicals, resulting in the high selectivity. It was found that the CHF3/O2 gas mixture plasma reacted with SiN, resulting in the formation of a protective reaction product that is considered to be an ammonium salt such as (NH4)2SiF6.

  18. Swine deep bedding ashes as a mineral additive for cement based mortar Cinzas de cama sobreposta de suínos como adição mineral em argamassas de cimento

    Directory of Open Access Journals (Sweden)

    Melissa Selaysim Di Campos

    2008-04-01

    Full Text Available The sustainability of intensive swine production demands alternative destinations for the generated residues. Ashes from swine rice husk-based deep bedding were tested as a mineral addition for cement mortars. The ashes were obtained at 400 to 600ºC, ground and sieved through a 325 mesh sieve (# 0.045 mm. The characterization of the ashes included the determination of the index of pozzolanic activity with lime. The ashes were also tested as partial substitutes of Portland cement. The mortars were prepared using a cement:sand proportion of 1:1.5, and with water/cement ratio of 0.4. Three percentages of mass substitution of the cement were tested: 10, 20 and 30%. Mortar performances were assessed at 7 and 28 days determining their compressive strength. The chosen condition for calcinations at the laboratory scale was related to the maximum temperature of 600ºC since the resulting ashes contained vitreous materials and presented satisfactory values for the pozzolanic index under analysis. The pozzolanic activity indicated promising results for ashes produced at 600ºC as a replacement of up to 30% in cement masses.A sustentabilidade das regiões de produção intensiva de suínos requer destinos alternativos para os resíduos gerados. Cinzas de cama sobreposta de suínos à base casca de arroz, foram testadas como adição mineral em substituição ao cimento. As cinzas foram obtidas nas temperaturas de 400 a 600ºC, moídas e passadas por peneira ABNT 325 (# 0,045 mm. A caracterização de cinzas incluiu a determinação do índice de atividade pozolânica com a cal. As cinzas também foram testadas como substitutos parciais de cimento Portland. As argamassas foram preparadas na proporção cimento:areia de 1:1,5 e com fator água-cimento de 0,4. Três porcentagens de substituição do cimento comercial foram usadas: 10, 20 e 30% em massa. O desempenho das argamassas foi avaliado aos 7 e aos 28 dias com a determinação da resistência

  19. Immobilization of heavy metals in polluted soils by the addition of zeolitic material synthesized from coal fly ash.

    Science.gov (United States)

    Querol, Xavier; Alastuey, Andrés; Moreno, Natàlia; Alvarez-Ayuso, Esther; García-Sánchez, Antonio; Cama, Jordi; Ayora, Carles; Simón, Mariano

    2006-01-01

    The use of zeolitic material synthesized from coal fly ash for the immobilization of pollutants in contaminated soils was investigated in experimental plots in the Guadiamar Valley (SW Spain). This area was affected by a pyrite slurry spill in April 1998. Although reclamation activities were completed in a few months, residual pyrite slurry mixed with soil accounted for relatively high leachable levels of trace elements such as Zn, Pb, As, Cu, Sb, Co, Tl and Cd. Phytoremediation strategies were adopted for the final recovery of the polluted soils. The immobilization of metals had previously been undertaken to avoid leaching processes and the consequent groundwater pollution. To this end, 1100 kg of high NaP1 (Na6[(AlO2)6(SiO2)10] .15H2O) zeolitic material was synthesized using fly ash from the Teruel power plant (NE Spain), in a 10 m3 reactor. This zeolitic material was manually applied using different doses (10000-25000 kg per hectare), into the 25 cm topsoil. Another plot (control) was maintained without zeolite. Sampling was carried out 1 and 2 years after the zeolite addition. The results show that the zeolitic material considerably decreases the leaching of Cd, Co, Cu, Ni, and Zn. The sorption of metals in soil clay minerals (illite) proved to be the main cause contributing to the immobilization of these pollutants. This sorption could be a consequence of the rise in pH from 3.3 to 7.6 owing to the alkalinity of the zeolitic material added (caused by traces of free lime in the fly ash, or residual NaOH from synthesis).

  20. Effects of waste glass and waste foundry sand additions on reclaimed tiles containing sewage sludge ash.

    Science.gov (United States)

    Lin, Deng-Fong; Luo, Huan-Lin; Lin, Kuo-Liang; Liu, Zhe-Kun

    2017-07-01

    Applying sewage sludge ash (SSA) to produce reclaimed tiles is a promising recycling technology in resolving the increasing sludge wastes from wastewater treatment. However, performance of such reclaimed tiles is inferior to that of original ceramic tiles. Many researchers have therefore tried adding various industrial by-products to improve reclaimed tile properties. In this study, multiple materials including waste glass and waste foundry sand (WFS) were added in an attempt to improve physical and mechanical properties of reclaimed tiles with SSA. Samples with various combinations of clay, WFS, waste glass and SSA were made with three kiln temperatures of 1000°C, 1050°C, and 1100°C. A series of tests on the samples were next conducted. Test results showed that waste glass had positive effects on bending strength, water absorption and weight loss on ignition, while WFS contributed the most in reducing shrinkage, but could decrease the tile bending strength when large amount was added at a high kiln temperature. This study suggested that a combination of WFS from 10% to 15%, waste glass from 15% to 20%, SSA at 10% at a kiln temperature between 1000°C and 1050°C could result in quality reclaimed tiles with a balanced performance.

  1. Evaluation of the Addition of Wood Ash to Control the pH of Substrates in Municipal Biowaste Composting

    Directory of Open Access Journals (Sweden)

    Oviedo-Ocaña Edgar Ricardo

    2014-07-01

    Full Text Available This study evaluates the addition of wood ashes (WA for controlling the pH of substrates in municipal biowaste (MBW composting. Three combinations in wet weight percent (w/w of MBW and WA were tested: i BC1: 2% WA and 98% MBW; ii BC2: 4% WA and 96% MBW; and iii BC3: 8% WA and 92% MBW. Each combination was compared with a control (100% MBW called B1, B2 and B3 respectively. The experiment was conducted to pilot scale, with piles of 510 kg. The results indicate that the addition of WA improved the pH level and nutrients for the composting process; however, it had not substantial benefit in the process (start of the thermophilic phase and the behavior of the substrate degradation rate. Furthermore, a higher presence of salts and phytotoxic compounds in the product was observed. This could limit the product use for agricultural activities.

  2. Compost maturity and nitrogen availability by co-composting of paddy husk and chicken manure amended with clinoptilolite zeolite.

    Science.gov (United States)

    Latifah, Omar; Ahmed, Osumanu Haruna; Susilawati, Kassim; Majid, Nik Muhamad

    2015-04-01

    The availability of paddy husk from rice processing plants remains high owing to increase in the worldwide rice consumption. Increasing demand for chicken products leads to poultry wastes production. Co-composting of the aforementioned wastes could solve the indiscriminate disposal of these wastes. Thus, co-composting of paddy husk and chicken slurry with clinoptilolite zeolite and urea as additive was carried out. Clinoptilolite zeolite was used to enhance ammonium and nitrate retention in the compost. Temperature of the compost was monitored three times daily for 55 days. Cation exchange capacity, organic matter, ash, humic acids, pH, total C, N, C/N ratio; total P, exchangeable Ca, Mg, K, NH4+, NO3-, and heavy metals contents were determined using standard procedures. pH, total N, humic acids, ash, NH4+, NO3-, P, Ca, Mg, and K contents increased but the salinity, heavy metals contents, and microbial population were low after the co-composting process. Zea mays L. (test crop) seed germination rate in distilled water and the compost were not significantly different. Growth of Spinach oleracea (test crop) on a peat-based growing medium and the compost was also not significantly different. These findings were possible because the clinoptilolite zeolite used in co-composting reduced accumulation of heavy metals that may have damage effects on the test crops. Mature compost with good agronomic properties can be produced by co-composting chicken slurry and paddy husk using clinoptilolite zeolite and urea as additives. © The Author(s) 2015.

  3. The influence of α-Al2O3 addition on microstructure, mechanical and formaldehyde adsorption properties of fly ash-based geopolymer products.

    Science.gov (United States)

    Huang, Yi; Han, Minfang

    2011-10-15

    Fly ash-based geopolymer with α-Al(2)O(3) addition were synthesized and used to remove formaldehyde from indoor air. The microstructure, mechanical and formaldehyde adsorption properties of the geopolymer products obtained were investigated. The results showed that α-Al(2)O(3) addition with appropriate amount (such as 5 wt%) increased the geopolymerization extent, resulting in the increase of surface area and compressive strength. In addition, the improvement of structural ordering level for geopolymer sample with 5 wt% α-Al(2)O(3) addition was found through FTIR analysis. By contrast, excessive addition (such as 10 wt%) had the opposite effect. The test of formaldehyde adsorption capacity confirmed that fly ash-based geopolymer product exhibited much better property of adsorbing indoor formaldehyde physically and chemically than fly ash itself. The surface area was an important but not unique factor influencing the adsorption capacity of geopolymers. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. A comparative study on different burning method of sewage sludge ash in mortar brick with eggshell powder as additive

    Science.gov (United States)

    Ing, Doh Shu; Azed, Muhammad Aizat; Chin, Siew Choo

    2017-11-01

    Population growth that increase every year has led to the increasing amount of waste generated annually. The content of heavy metal Cadmium (Cd), Lead (Pb) and Zinc (Zn) represent the biggest concentrations of heavy metals in sewage sludge waste which can be the source of pollution. Furthermore, the excessive disposal of eggshells waste to landfills may attract rats and worms due to the organic protein matrix that may pose health problem to the public. In the last decade, the demand on cement mortar brick has increased has resulted in higher cement production. However, cement plant is one of the major contributors of carbon dioxide emission. Hence, this research focuses on the production of environmental friendly cement with sewage sludge since there is occurrence of pozolonic material in Sewage Sludge Ash (SSA). From the initial finding, the major components of SSA are Silicon Dioxide (SiO2), Calcium oxide (CaO), Aluminium Oxide (Al2O3), Iron (III) Oxide (Fe2O3), Sodium Oxide (Na2O), Potassium oxide (K2O), Magnesium Oxide (MgO) and Iron (II) Oxide (FeO). Sewage sludge needed to be incinerated to remove the heavy metal before it can be used as cement replacement in mortar brick production. The sewage sludge were treated using two methods namely incineration and microwave. Both types of sewage sludge were then added with eggshell powder as additive. Eggshell powder act as additive in this research due to its high content of calcium carbonate and has nearly same composition of limestone used in the production of cement. Different percentages of Eggshell Powder (ESP) (0%, 5%, 10%, 15%) and 10% fixed of Microwaved Sewage Sludge Ash (MSSA) and Incinerated Sewage Sludge Ash (ISSA) as optimum dosage partially replacing the cement used to test the brick mortar properties in term of compressive strength, flexural strength and also water absorption. Result showed that ISSA with 5% of ESP is the most optimum brick with highest compressive strength and flexural strength

  5. Impact of Coal Fly Ash Addition on Combustion Aerosols (PM2.5) from Full-Scale Suspension-Firing of Pulverized Wood

    DEFF Research Database (Denmark)

    Damø, Anne Juul; Wu, Hao; Frandsen, Flemming

    2014-01-01

    The formation of combustion aerosols was studied in an 800 MWth suspension-fired power plant boiler, during combustion of pulverized wood pellets with and without addition of coal fly ash as alkali capture additive. The aerosol particles were sampled and characterized by a low-pressure cascade im...

  6. Studies on Thermal Degradation Behavior of Siliceous Agriculture Waste (Rice Husk, Wheat Husk and Bagasse)

    National Research Council Canada - National Science Library

    Syed H. Javed; Umair Aslam; Mohsin Kazmi; Masooma Rustam; Sheema Riaz; Zahid Munir

    2015-01-01

    Various siliceous agriculture waste (SAW) such as rice husk, wheat husk and bagasse have been investigated to study their thermal degradation behavior using Thermogravimetric Analyzer (TGA) technique...

  7. Effect of glass microfibre addition on the mechanical performances of fly ash-based geopolymer composites

    Directory of Open Access Journals (Sweden)

    Thamer Alomayri

    2017-09-01

    Full Text Available In the present study, various amounts of glass microfibres were introduced into a geopolymer for reinforcement purposes. The influence of these microfibres on the performance of the geopolymer composites was investigated. Results show that the appropriate addition of glass microfibres can improve the mechanical properties of geopolymer composites. In particular, the flexural strength, flexural modulus and impact strength increase at an optimum fibre content of 2 wt%. Further, adding glass microfibres to a plain geopolymer matrix has a significant effect on the pre-cracking behaviour. It substantially enhances the post-cracking response.

  8. Rice Husk Filled Polymer Composites

    National Research Council Canada - National Science Library

    Arjmandi, Reza; Hassan, Azman; Majeed, Khaliq; Zakaria, Zainoha

    2015-01-01

      Natural fibers from agricultural wastes are finding their importance in the polymer industry due to the many advantages such as their light weight, low cost and being environmentally friendly. Rice husk (RH...

  9. Effect of the addition of by-product ash of date palms on the mechanical characteristics of gypsum-calcareous materials used in road construction

    Science.gov (United States)

    Khellou, A.; Kriker, A.; Hafssi, A.; Belbarka, K.; Baali, K.

    2016-07-01

    The gypsum-calcareous materials, also known as the crusting tuff, are used in the pavement layers of low -traffic road and considered as the materials of first choice in the Saharan region of Algeria. The objective of this paper is to study the mechanical characteristics of tuff of Ouargla town that is situated in the Southeast of Algeria, by adding different percentage of ash resulted from the combustion of by-products of date palms, such as 4%, 8% and l2%, to the tuff. The results obtained have shown a remarkable improvement both in compressive strength at different ages and in the bearing index in the two cases immediate and after immersion in water. These characteristics of the mixture (tuff+ash) reach their maximum values at the 8% of ash addition.

  10. Study of the use of coal fly ash as an additive to minimise fluoride leaching from FGD gypsum for its disposal.

    Science.gov (United States)

    Alvarez-Ayuso, E; Querol, X

    2008-03-01

    The use of coal fly ash as a fluoride retention additive has been studied as a way of treating flue gas desulphurisation (FGD) gypsum for its disposal in landfills. With this end leaching studies following the standard EN-12457-4 [Characterization of waste- Leaching-Compliance test for leaching of granular waste materials and sludges - Part 4: One stage batch test at a liquid to solid ratio of 10l/kg for materials with particle size below 10mm (without or with size reduction)] have been performed on FGD gypsum samples treated with different proportions of fly ash (0.1-100%). It was found that the fluoride leachable content in FGD gypsum was reduced in the range 1-55%, depending on the fly ash proportion added to FGD gypsum. High levels of fluoride leaching reduction (close to 40%) were achieved even at relatively low fly ash additions (5%). So, low fly ash incorporations assure the characterization of this by-product as a waste acceptable at landfills for non-hazardous wastes according to the Council Decision 2003/33/EC [Council Decision 2003/33/EC of 19 December 2002 establishing criteria and procedures for the acceptance of waste at landfills pursuant to Article 16 of and Annex II to Directive 1999/31/EC] on waste disposal. Furthermore, the effectiveness of the proposed FGD gypsum stabilization method was also studied in column leaching systems, proving its good performance in simulated conditions of disposal. In such conditions a fluoride leaching reduction value slightly higher than 25% was displayed for a fly ash added amount of 5%.

  11. Proximate Composition, Extraction, and Purification of Theobromine from Cacao Pod Husk (Theobroma Cacao L.

    Directory of Open Access Journals (Sweden)

    Van Tang Nguyen

    2017-04-01

    Full Text Available The aims of this study were to determine the proximate composition of cacao pod husk as well as the optimal conditions for extraction and purification of theobromine from cacao pod husk. The results indicated that cacao pod husk had high contents of moisture and carbohydrate (87.06% and 11.03% by fresh weight, respectively, but low contents of crude protein, crude lipid, and ash (0.31%, 0.12%, and 1.48% by fresh weight, respectively. The optimal conditions for extraction of theobromine from cacao pod husk were of 70% ethanol, with an extraction time of 90 min, and 1 as the number of extractions. A concentration of 10% by volume of 10% lead acetate solution was the best selection for purification of the crude extracts containing theobromine from cacao pod husk. Under these optimal conditions, theobromine content obtained from cacao pod husk was 6.79 mg/100 g dry weight. The finding from this study is a valuable contribution for obtaining theobromine from an abundant, inexpensive, renewable, and sustainable source for potential application in the nutraceutical, medical, and pharmaceutical industries.

  12. Effect of air-cooled slag and granulated blast furnace slag addition as substitutor on fly ash based geopolymer

    Science.gov (United States)

    Harmaji, Andrie; Imran, Aishah Mahyarni; Sunendar, Bambang; Lazuardi, Muhammad Sofyan; Khairunnasari, Ikhsan; Sobandi, Ahmad

    2017-09-01

    Air Cooled Slag and Granulated Blast Furnace Slag is a waste material from steelmaking process that not utilized, even though it rich in silica and CaO that can increase mechanical properties of building materials. Therefore, this material is potential as substitutor for geopolymer. Geopolymer is an alkali activated material consists of aluminosilicate precursor activated by NaOH and waterglass as activator. One of the common aluminosilicate binder used is fly ash. Geopolymer was made by mixing fly ash and air cooled slag or granulated blast furnace slag in certain ratio with alkali activator solution. The aim for this study is to obtain the best ratio of slag to fly ash binder that produces the highest compressive strength. The best compressive strength was 29.80 MPa achieved in fly ash:air cooled slag 40:60 ratio and 31.33 MPa achieved in fly ash:granulated blast furnace slag 40:60 ratio. X-Ray Diffraction test showed the appearance of anorthite (Ca, Na (Al, Si)4 O8). FTIR characterization showed the appearance of siloxo and sialate bonding which commonly found in geopolymerization.

  13. Integrated management of ash from industrial and domestic combustion : a new sustainable approach for reducing greenhouse gas emissions from energy conversion

    OpenAIRE

    Benassi, L.; R. Dalipi; Consigli, V; Pasquali, M.; Borgese, L.; Depero, L.E.; Clegg, Francis; Bingham, Paul; Bontempi, E.

    2017-01-01

    This work supports, for the first time, the integrated management of waste materials arising from industrial processes (fly ash from municipal solid waste incineration and coal fly ash), agriculture (rice husk ash), and domestic activities (ash from wood biomass burning in domestic stoves). The main novelty of the paper is the reuse of wood pellet ash, an underestimated environmental problem, by the application of a new technology (COSMOS-RICE) that already involves the reuse of fly ashes fro...

  14. Experimental Investigation of Thermal Characteristics of Kiwira Coal Waste with Rice Husk Blends for Gasification

    Directory of Open Access Journals (Sweden)

    Deodatus Kazawadi

    2014-01-01

    Full Text Available Eminent depletion of fossil fuels and environmental pollution are the key forces driving the implementation cofiring of fossil fuels and biomass. Cogasification as a technology is known to have advantages of low cost, high energy recovery, and environmental friendliness. The performance/efficiency of this energy recovery process substantially depends on thermal properties of the fuel. This paper presents experimental study of thermal behavior of Kiwira coal waste/rice husks blends. Compositions of 0, 20, 40, 60, 80, and 100% weight percentage rice husk were studied using thermogravimetric analyzer at the heating rate of 10 K/min to 1273 K. Specifically, degradation rate, conversion rate, and kinetic parameters have been studied. Thermal stability of coal waste was found to be higher than that of rice husks. In addition, thermal stability of coal waste/rice husk blend was found to decrease with an increase of rice husks. In contrast, both the degradation and devolatilization rates increased with the amount of rice husk. On the other hand, the activation energy dramatically reduced from 131 kJ/mol at 0% rice husks to 75 kJ/mol at 100% rice husks. The reduction of activation energy is advantageous as it can be used to design efficient performance and cost effective cogasification process.

  15. Influence of Pyrolysis Temperature on Rice Husk Char Characteristics and Its Tar Adsorption Capability

    Directory of Open Access Journals (Sweden)

    Anchan Paethanom

    2012-11-01

    Full Text Available A biomass waste, rice husk, was inspected by thermoanalytical investigation to evaluate its capability as an adsorbent medium for tar removal. The pyrolysis process has been applied to the rice husk material at different temperatures 600, 800 and 1000 °C with 20 °C/min heating rate, to investigate two topics: (1 influence of temperature on characterization of rice husk char and; (2 adsorption capability of rice husk char for tar removal. The results showed that subsequent to high temperature pyrolysis, rice husk char became a highly porous material, which was suitable as tar removal adsorbent with the ability to remove tar effectively. In addition, char characteristics and tar removal ability were significantly influenced by the pyrolysis temperature.

  16. Reduction of indicator and pathogenic microorganisms in pig manure through fly ash and lime addition during alkaline stabilization.

    Science.gov (United States)

    Wong, Jonathan W C; Selvam, Ammaiyappan

    2009-09-30

    A pilot scale study was conducted to evaluate the effect of lime and alkaline coal fly ash (CFA) on the reduction of pathogens in pig manure during alkaline stabilization and suppression of re-growth during post-stabilization incubation. Pig manure was mixed with CFA at 25%, 33% and 50%, and a control without fly ash was maintained. To these manure-ash mixtures, lime was added at the rate of 2% or 4% and incubated for 8 days. During the incubation, the population of Salmonella, fecal coliforms, Escherichia coli, fecal Streptococcus and total bacteria were enumerated. After the alkaline stabilization process, the mixtures were incubated under green house condition to evaluate the re-growth of pathogens. During the 8-day alkaline stabilization, Salmonella, fecal coliforms, E. coli and fecal Streptococcus were completely devitalized in manure-ash-lime mixtures, whereas in the control, incubation reduced the pathogen and total bacterial population by 2-3 logs. Fecal streptococcus was destructed within 4 days of alkaline stabilization, whereas other pathogens needed 8 days for their destruction. During the incubation in green house, an increase in the population of the pathogens and total bacteria was observed. Results indicate that alkaline stabilization of pig manure with lime at 4% and CFA at 50% is effective in devitalizing the pathogens and reducing the post-stabilization re-growth.

  17. Use of rice husk for emission neutral energy generation and synthesis of solar-grade silicon feedstock

    Energy Technology Data Exchange (ETDEWEB)

    Larbi, K.K. [Starkey and Associates Inc., Oakville, ON (Canada); Roy, R. [University of Toronto, Toronto, ON (Canada); Barati, M.; McLean, A. [University of Toronto, Department of Materials Science and Engineering, Toronto, ON (Canada); Lakshmanan, V.I.; Sridhar, R. [Process Research Ortech Inc., Mississauga, ON (Canada)

    2012-06-15

    The potential use of rice husk as a source of energy and also for producing high-purity silicon has been investigated by a combination of pilot trials, theoretical calculations and laboratory experiments. Rice husk was combusted at 850 C. Mass balance together with the pilot results indicates an electricity generation potential of 1 MWh per tonne rice husk. The process also generates 180 kg rice husk ash (RHA) that is used for production of high-purity silicon through a hybrid pyrometallurgical-hydrometallurgical process. The process consists of three major steps: purification of RHA by leaching and roasting, reduction by magnesium and recovery of silicon through two steps of leaching. The silicon generation process steps were optimized, showing that about 85% of silicon in the RHA can be recovered. The silicon product has a total impurity of <0.7%, hence it may be used as a suitable feedstock for production of solar-grade silicon. (orig.)

  18. Characterization of silica distribution in rice husk using Synchrotron Radiation µCT and its implications for archaeological interpretation.

    Science.gov (United States)

    Wu, Yan; Yang, Yimin; Xiao, Tiqiao; Gu, Zhou; Hill, David V; Wang, Changsui

    2014-10-01

    This article reports the results of a pilot project using Synchrotron Radiation µCT (computer-aided tomography) to examine the distribution of silica within phytoliths from rice husks. Experiments indicate that computed tomography can be used to show how silica accumulates and is distributed in a distinctive zigzag pattern of long epidermal cells that are characteristic of phytoliths from rice husks. This method will help us to understand why the dry ashing method produced much more zigzag pattern of long cells phytoliths from rice husk than did the acid extraction method. Besides, the zigzag morphological pattern exhibited by long epidermal cells is characteristic of this species which makes it useful in the identification of rice husks from archaeological contexts and indicating heating process. © 2014 Wiley Periodicals, Inc.

  19. The content of chromium and copper in plants and soil fertilized with sewage sludge with addition of various amounts of CaO and lignite ash

    Directory of Open Access Journals (Sweden)

    Wysokiński Andrzej

    2016-09-01

    Full Text Available The influence of fertilization with fresh sewage sludge with the addition of calcium oxide and lignite ash in the proportions dry mass 6:1, 4:1, 3:1 and 2:1 on the content of chromium and copper in plants and soil and uptake of these elements was investigated in pot experiment. Sewage sludge were taken from Siedlce (sludge after methane fermentation and Łuków (sludge stabilized in oxygenic conditions, eastern Poland. The chromium content in the biomass of the test plants (maize, sunflower and oat was higher following the application of mixtures of sewage sludge with ash than of the mixtures with CaO. The copper content in plants most often did not significantly depend on the type of additives to the sludge. Various amounts of additives to the sewage sludge did not have a significant effect on the contents of either of the studied trace elements in plants. The contents of chromium and copper in soil after 3 years of cultivation of plants were higher than before the experiment, but these amounts were not significantly differentiated depending on the type and the amount of the used additive (i.e. CaO vs. ash to sewage sludge.

  20. Differential growth and yield by canola (Brassica napus L.) and wheat (Triticum aestivum L.) arising from alterations in chemical properties of sandy soils due to additions of fly ash.

    Science.gov (United States)

    Yunusa, Isa A M; Manoharan, Veeragathipillai; Harris, Rob; Lawrie, Roy; Pal, Yash; Quiton, Jonathan T; Bell, Richard; Eamus, Derek

    2013-03-30

    There is a need for field trials on testing agronomic potential of coal fly ash to engender routine use of this technology. Two field trials were undertaken with alkaline and acidic fly ashes supplied at between 3 and 6 Mg ha⁻¹ to acidic soils and sown to wheat and canola at Richmond (Eastern Australia) and to wheat only at Merredin (Western Australia). Ash addition marginally (Pwheat was observed; canola increased accumulation of Mo and Se in its shoot with acidic fly ash, but it was well below phyto toxic levels. Simulations of wheat using APSIM at Richmond over a 100-year period (1909-2008) predicted yield increases in 52% of years with addition of ash at 3.0 Mg ha⁻¹ compared with 24% of years with addition of ash at 6.0 Mg ha⁻¹. The simulated yield increases did not exceed 40% over the control with addition of 6 Mg ha⁻¹ ash, but was between 40% and 50% with an addition rate of 3 Mg ha⁻¹. We found no evidence of phytotoxicity in either crop in this unusually dry year and there is still a need for further field assessment in years with favourable rainfall to enable development of clear recommendations on fly ash rates for optimum yield benefits. © 2012 Society of Chemical Industry.

  1. ashing, non-ashing

    African Journals Online (AJOL)

    cistvr

    Three commonly used techniques, namely atomic absorption spectrophotometry (AAS-Ashing and. AAS-Non Ashing) and titrimetry (potassium permanganate titration) have been evaluated in this study to determine the calcium content in six food samples whose calcium levels ranged from 0 to more than. 250mg/100g ...

  2. Effect of demineralization on the physiochemical structure and thermal degradation of acid treated indigenous rice husk

    Directory of Open Access Journals (Sweden)

    Aslam Umair

    2016-09-01

    Full Text Available Energy generation from biomass presents some serious problems like slagging, fouling and corrosion of boilers. To address these problems, demineralization of biomass is performed using different leaching agents. This study is focused on determining the influence of leaching agents and leaching time on the physiochemical structure of rice husk during demineralization. Dilute (5% wt solutions of HCl and H2SO4 were used for the demineralization of rice husk separately with leaching time of 15, 60 and 120 minutes. It is shown that H2SO4 exhibited higher removal of alkali and alkaline earth metals (AAEM comparatively as depicted by the 34.2% decrease in ash content along with an increase of 7.10% in the heating value. The acid has been seen to induce more notable changes in physiochemical structure as depicted by the FTIR spectra and SEM micrographs. The thermal degradation behavior of the demineralized rice husk has also been reported.

  3. Elucidation of the effect of ionic liquid pretreatment on rice husk via structural analyses.

    Science.gov (United States)

    Ang, Teck Nam; Ngoh, Gek Cheng; Chua, Adeline Seak May; Lee, Min Gyu

    2012-09-07

    In the present study, three ionic liquids, namely 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc), and 1-ethyl-3-methylimidazolium diethyl phosphate ([EMIM]DEP), were used to partially dissolve rice husk, after which the cellulose were regenerated by the addition of water. The aim of the investigation is to examine the implications of the ionic liquid pretreatments on rice husk composition and structure. From the attenuated total reflectance Fourier transform-infrared (ATR FT-IR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) results, the regenerated cellulose were more amorphous, less crystalline, and possessed higher structural disruption compared with untreated rice husk. The major component of regenerated cellulose from [BMIM]Cl and [EMIM]DEP pretreatments was cellulose-rich material, while cellulose regenerated from [EMIM]OAc was a matrix of cellulose and lignin. Cellulose regenerated from ionic pretreatments could be saccharified via enzymatic hydrolysis, and resulted in relatively high reducing sugars yields, whereas enzymatic hydrolysis of untreated rice husk did not yield reducing sugars. Rice husk residues generated from the ionic liquid pretreatments had similar chemical composition and amorphousity to that of untreated rice husk, but with varying extent of surface disruption and swelling. The structural architecture of the regenerated cellulose and rice husk residues showed that they could be used for subsequent fermentation or derivation of cellulosic compounds. Therefore, ionic liquid pretreatment is an alternative in the pretreatment of lignocellulosic biomass in addition to the conventional chemical pretreatments.

  4. Characterisation of silica derived from rice husk (Muar, Johor, Malaysia) decomposition at different temperatures

    Science.gov (United States)

    Azmi, M. A.; Ismail, N. A. A.; Rizamarhaiza, M.; W. M. Hasif. A. A., K.; Taib, H.

    2016-07-01

    Rice husk was thermally decomposed to yield powder composed of silica (SiO2). Temperatures of 700°C and 1000°C were chosen as the decomposition temperatures. X-Ray Diffraction (XRD), X-Ray Florescence (XRF), Fourier Transform Infrared (FTIR), and Field Emission Scanning Electron Microscope (FESEM) analyses were conducted on a synthetic silica powder (SS-SiO2) and the rice husk ash as for the comparative characterisation study. XRD analyses clearly indicated that the decomposed rice husk yielded silica of different nature which are Crystalline Rice Husk Silica (C-RHSiO2) and Amorphous Rice Husk Silica (A-RHSiO2). Moreover, it was found that SS-SiO2 was of Quartz phase, C-RHSiO2 was of Trydimite and Cristobalite. Through XRF detection, the highest SiO2 purity was detected in SS-SiO2 followed by C-RHSiO2 and A-RHSiO2 with purity percentages of 99.60%, 82.30% and 86.30% respectively. FTIR results clearly indicated silica (SiO2) bonding 1056, 1064, 1047, 777, 790 and 798 cm-1) increased as the crystallinity silica increased. The Cristobalite phase was detected in C-RH SiO2 at the wavelength of 620 cm-1. Morphological features as observed by FESEM analyses confirmed that, SS-SiO2 and C-RH SiO2 showed prominent coarse granular morphology.

  5. Analysis of Energy Characteristics of Rice and Coffee Husks Blends

    National Research Council Canada - National Science Library

    Cuthbert F. Mhilu

    2014-01-01

    .... This paper reports work done to determine energy characteristics of rice and coffee husks. The results show that coffee husks have better energy quality than rice husks, while heating values of coffee are 18.34 MJ/kg...

  6. removal of heavy metal ions from aqueous solution using rice husks ...

    African Journals Online (AJOL)

    User

    R had average particle sizes of 336.8, 296.4 and 1054.1 nm and BET surface areas of 17.8, 20.2 and 5.7 m2/g, in the same order. ..... Husk Ash as Green Corrosion. Inhibitor. Int. J. Electrochem. Sci. 8: 1759-1769. Bhattacharya AK, Mandal SN and Das SK. 2006 Removal of Cr(VI) from. Aqueous Solution by Adsorption ...

  7. Effects of pyrolysis temperature, time and leaf litter and powder coal ash addition on sludge-derived adsorbents for nitrogen oxide.

    Science.gov (United States)

    Ren, Xiaoli; Liang, Baohong; Liu, Min; Xu, Xiaoyuan; Cui, Meihua

    2012-12-01

    The objective of this research was to seek a cost effective solution to prepare adsorbents for nitrogen oxide from surplus sludge. Leaf litter and powder coal ash were used as cheap and easily available additives. An adsorbent for nitrogen oxide was prepared by pyrolysis of dried sludge mixed with zinc chloride. Under optimum pyrolysis conditions of 375°C for 90 min and a zinc chloride content of 30%, the surface area of the adsorbent with leaf litter was 514.41 m(2)/g, the surface area of the adsorbent with powder coal ash was 432.34 m(2)/g, respectively, corresponding to an increase of 90.70% and 60.27% when compared to the adsorbent without the additives. The saturated adsorption quantity of the adsorbent with leaf litter reached 271 mg/g at 20°C. The results indicated that the sludge-derived adsorbent was quite promising for nitrogen oxide removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Prediction total specific pore volume of geopolymers produced from waste ashes by fuzzy logic

    Directory of Open Access Journals (Sweden)

    Ali Nazari

    2012-04-01

    Full Text Available In the present work, total specific pore volume of inorganic polymers (geopolymers made from seeded fly ash and rice husk bark ash has been predicted by fuzzy logic. Different specimens, made from a mixture of fly ash and rice husk bark ash in fine and coarse form together with alkali activator made of water glass and NaOH solution, were subjected to porosimetry tests at 7 and 28 days of curing. The curing regime was different: one set of the specimens were cured at room temperature until reaching to 7 and 28 days and the other sets were oven cured for 36 hours at the range of 40-90 °C and then cured at room temperature until 7 and 28 days. A model based on fuzzy logic for predicting the total specific pore volume of the specimens has been presented. To build the model, training and testing using experimental results from 120 specimens were conducted. The used data as the inputs of fuzzy logic models are arranged in a format of six parameters that cover the percentage of fine fly ash in the ashes mixture, the percentage of coarse fly ash in the ashes mixture, the percentage of fine rice husk bark ash in the ashes mixture, the percentage of coarse rice husk bark ash in the ashes mixture, the temperature of curing and the time of water curing. According to the input parameters, in the fuzzy logic model, the pore volume of each specimen was predicted. The training and testing results in the fuzzy logic model have shown a strong potential for predicting the total specific pore volume of the geopolymer specimens in the considered range.

  9. Formation of porous clay ceramic using sago waste ash as a prospective additive material with controllable milling

    Directory of Open Access Journals (Sweden)

    Aripin H.

    2014-01-01

    Full Text Available A novel type of ceramic material was produced by mixing sago waste ash from the sago processing industry in Indonesia with clay. The composition was prepared by adding 50 %wt amount of sago waste into the clay, then a series of samples was milled for 6 h, 12 h, 24 h and 48 h, respectively. The samples were dry pressed and sintered at temperatures ranging from 800°C to 1200°C. The influence of the sintering temperature and the milling time on bulk density, firing shrinkage, water adsorption, and hardness was studied in detail. The results demonstrate that the low water absorption of less than 0.5% and the highest hardness of 5.82 GPa were obtained for the sample sintered at 1100°C and milled for 48 h. The investigation of the absorptive properties of such ceramics indicates that they could be recommended as a promising material for manufacturing of unglazed floor tiles.

  10. Palm Kernel Husk Ash (PKHA) as an Admixture (Accelerator) in ...

    African Journals Online (AJOL)

    Almost all admixtures used in concrete production in Nigeria are imported. This study was carried out to determine the suitability of PKHA as an admixture, while still retaining the compressive strength characteristics. Results revealed that the setting time of the mixture of the PKHA and cement cube decreases as the ...

  11. EFFECT OF ALUMINUM DROSS AND RICE HUSK ASH ON ...

    African Journals Online (AJOL)

    Moulding properties of foundry sand should be controlled so as to minimize casting defects. Its thermal characteristics are vital in defining the solidification kinetics of a cast part, evolving microstructure and mechanical properties. Modification of the thermal properties of the moulding sand mix is important in achieving ...

  12. Energy potential from rice husk through direct combustion and fast pyrolysis: A review.

    Science.gov (United States)

    Quispe, Isabel; Navia, Rodrigo; Kahhat, Ramzy

    2017-01-01

    Rapid population growth and consumption of goods and services imply that demand for energy and resources increases continuously. Energy consumption linked to non-renewable resources contributes to greenhouse gas emissions and enhances resource depletion. In this context, the use of agricultural solid residues such as rice husk, coffee husk, wheat straw, sugar cane bagasse, among others, has been widely studied as an alternative energy source in order to decrease the use of fossil fuels. However, rice husk is among those agricultural residues that are least used to obtain energy in developing countries. Approximately 134 million tonnes of rice husk are produced annually in the world, of which over 90% are burned in open air or discharged into rivers and oceans in order to dispose of them. This review examines the energetic potential of agricultural residues, focused on rice husk. The review describes direct combustion and fast pyrolysis technologies to transform rice husk into energy considering its physical and chemical properties. In addition, a review of existing studies analyzing these technologies from an environmental life cycle thinking perspective, contributing to their sustainable use, is performed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Palm Ash as an Alternative Source for Silica Production

    Directory of Open Access Journals (Sweden)

    Pa Faizul Che

    2016-01-01

    Full Text Available Agricultural wastes such as palm ash and rice husk have a possibility to be used as a useful renewable source for the production of silica (SiO2. Extensive researches have been carried out to extract silica from agricultural wastes such as rice husk, due to silica as a useful raw material for industrial application. In this study, the environmentally benign and economically effective process to produce SiO2 materials from palm ash has been established by using citric acid leaching, not the conventional strong acids. Results showed that silica can be extracted from palm ash using the citric acid leaching method under the optimum extracting conditions with 700 °C of solution temperature, 60 minutes of reaction time and concentration of citric acid of more than 2 %. The purity of silica extracted is more than 90 %.

  14. Effects of wood-ash addition on nitrogen turnover in a highly nitrogen loaded spruce site. Final project report; Effekter av askaaterfoering paa kvaeveomsaettningen i ett kvaeverikt granbestaand i Halland. Slutrapport foer projektet

    Energy Technology Data Exchange (ETDEWEB)

    Nohrstedt, H.Oe.; Hoegbom, Lars; Nordlund, Sten [Forestry Research Inst. of Sweden, Uppsala (Sweden)

    2000-04-01

    During two consecutive years, it was studied how a fertilization with 4.2 tonnes pelleted bark ash per ha, made six-seven years earlier, affected soil chemistry, nitrogen turnover and soil-water chemistry on a Norway spruce site in SW Sweden. The actual site has a very acidic soil. At the same time, the supply of inorganic N is rich. Measures against soil acidification, e. g. addition of ash or lime, may significantly influence the turnover of N with a subsequent risk for increased leaching. Thus, there is a potential conflict between two urgent environmental goals, i. e. to decrease acidification and to decrease the N load on aquatic ecosystems. In the humus layer and the upper 5 cm of the mineral soil, pH(H{sub 2}O) had increased with at the most 0.2 units because of the ash addition. The easily extractable amounts of Mg, P and nitrate were slightly increased. The potential nitrification in the humus layer was generally higher in the ash treatment, but the difference. was not statistically significant. The soil water at 50 cm depth was 0.1-0.2 pH-units more acidic where ash had been applied. Simultaneously, there were tendencies for higher concentrations of nitrate, Al and K. This is the first time in Sweden that ash fertilization of a closed forest has given clear indications of an increased N leaching. As expected, the ash fertilization decreased the acidity of the top soil. On the contrary, the runoff became more acidic and more rich in Al. Thus, the ash fertilization has counteracted one of its primary goals, i. e. to produce a runoff less toxic to aquatic life. The acidification of the runoff may partially be because of acid production during nitrification.

  15. Briquettes of rice husk, polyethylene terephthalate (PET), and dried leaves as implementation of wastes recycling

    Science.gov (United States)

    Hariyanto, Sucipto; Usman, Mohammad Nurdianfajar; Citrasari, Nita

    2017-06-01

    This research aim is to determine the best briquettes as implementation of wastes recycle based on scoring method, main component composition, compressive strength, caloric value, water content, vollatile content, and ash content, also the suitability with SNI 01-6235-2000. Main component that used are rice husk, 2mm and 6 mm PET, and dried leaves. Composition variation in this research are marked as K1, K2, K3, K4, and K5 with 2 mm PET plastic and K1, K2, K3, K4, and K5 with 6 mm PET plastic. The total weight of the briquettes is 100 g and divided into 90% main components and 10% tapioca as binder. The compressive strength, caloric value, water content, vollatile content, and ash content were tested according to ASTM D 5865-04, ASTM D 3173-03, ASTM D 3175-02, ASTM D 3174-02. The tested results were used to determine the best briquette by scoring method, and the chosen briquettes is K2 with 6 mm PET plastic. The composition is 70% rice husk, 20% 6 mm PET plastic, and 10% dried leaves with the compressive strength, caloric value, water content, vollatile content, and ash content value is 51,55 kg/cm2; 5123 kal/g; 3,049%; 31,823%, dan 12,869%. The suitable value that meet the criteria according to SNI 01-6235-2000 is compressive strength, caloric value, water content, and ash content.

  16. Characterization of geopolymer fly-ash based foams obtained with the addition of Al powder or H{sub 2}O{sub 2} as foaming agents

    Energy Technology Data Exchange (ETDEWEB)

    Ducman, V., E-mail: vilma.ducman@zag.si; Korat, L.

    2016-03-15

    Recent innovations in geopolymer technology have led to the development of various different types of geopolymeric products, including highly porous geopolymer-based foams, which are formed by the addition of foaming agents to a geopolymer fly-ash based matrix. These agents decompose, or react with the liquid matrix or oxygen in the matrix, resulting in the release of gases which form pores prior to the hardening of the gel. The hardened structure has good mechanical and thermal properties, and can therefore be used for applications in acoustic panels and in lightweight pre-fabricated components for thermal insulation purposes. This study presents the results of the pore-forming process in the case when two different foaming agents, i.e. aluminium powder amounting to 0.07, 0.13 and 0.20 mass. % and H{sub 2}O{sub 2} amounting to 0.5, 1.0, 1.5 and 2.0 mass. %, were added to a fly-ash geopolymer matrix. The physical, mechanical, and microstructural properties of the thus obtained foams, and the effects of the type and amount of the added foaming agent, are presented and discussed. Highly porous structures were obtained in the case of both of the investigated foaming agents, with overall porosities up to 59% when aluminium powder was added, and of up 48% when H{sub 2}O{sub 2} was added. In the latter case, when 2% of the H{sub 2}O{sub 2} foaming agent was added, finer pores (with diameters up to 500 μm) occurred in the structure, whereas somewhat larger pores (some had diameters greater than 1 mm) occurred when the same amount of aluminium powder was added. The mechanical properties of the investigated foams depended on their porosity. In the case of highly porous structures a compressive strength of 3.3 MPa was nevertheless achieved for the samples containing 0.2% of aluminium powder, and 3.7 MPa for those containing 2.0% of H{sub 2}O{sub 2}. - Highlights: • Preparation of geopolymer foams based on fly ash with the addition of Al powder or H{sub 2}O{sub 2} as

  17. Long-term growth responses of ash addition and liming - Preliminary results from a pilot study; Laangtidseffekter paa skogsproduktion efter askaaterfoering och kalkning - Preliminaera resultat fraan en pilotstudie

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem, Ulf; Jacobson, Staffan (Skogsbrukets Forskningsinstitut (Skogforsk), Uppsala Science Park, SE-751 83 Uppsala (Sweden)); Johansson, Ulf (Swedish University of Agricultural Sciences, The Unit for field-based forest research, Box 17, SE-310 38 Simlaangsdalen (Sweden)); Kukkola, Mikko; Saarsalmi, Anna (Metla, P.O. Box 18, FIN-01301 Vantaa (Finland)); Holt-Hansen, Kjersti (Norsk Institutt for skog og landskap, P.B. 115, NO-1431 Aas (Norway))

    2009-04-15

    Under this pilot study with preliminary results revealed trends in the experimental material which indicated that the addition of ashes or lime in the coniferous forest on mineral soil can lead to reduced stem growth on land with low fertility, unchanged stem growth in medium productive land, while growth may increase land with high fertility. This applied to both periods of 5-15 years and in the longer term (17-23 years; lime). Hence, the hypothesis, regarding the growth being dependent on soil fertility expressed as fertility, could not be rejected. However, previously reported indications of a similar connection with the C/N ratio in the humus was not confirmed in this first evaluation of the material

  18. Functional analysis of corn husk photosynthesis.

    Science.gov (United States)

    Pengelly, Jasper J L; Kwasny, Scott; Bala, Soumi; Evans, John R; Voznesenskaya, Elena V; Koteyeva, Nuria K; Edwards, Gerald E; Furbank, Robert T; von Caemmerer, Susanne

    2011-06-01

    The husk surrounding the ear of corn/maize (Zea mays) has widely spaced veins with a number of interveinal mesophyll (M) cells and has been described as operating a partial C(3) photosynthetic pathway, in contrast to its leaves, which use the C(4) photosynthetic pathway. Here, we characterized photosynthesis in maize husk and leaf by measuring combined gas exchange and carbon isotope discrimination, the oxygen dependence of the CO(2) compensation point, and photosynthetic enzyme activity and localization together with anatomy. The CO(2) assimilation rate in the husk was less than that in the leaves and did not saturate at high CO(2), indicating CO(2) diffusion limitations. However, maximal photosynthetic rates were similar between the leaf and husk when expressed on a chlorophyll basis. The CO(2) compensation points of the husk were high compared with the leaf but did not vary with oxygen concentration. This and the low carbon isotope discrimination measured concurrently with gas exchange in the husk and leaf suggested C(4)-like photosynthesis in the husk. However, both Rubisco activity and the ratio of phosphoenolpyruvate carboxylase to Rubisco activity were reduced in the husk. Immunolocalization studies showed that phosphoenolpyruvate carboxylase is specifically localized in the layer of M cells surrounding the bundle sheath cells, while Rubisco and glycine decarboxylase were enriched in bundle sheath cells but also present in M cells. We conclude that maize husk operates C(4) photosynthesis dispersed around the widely spaced veins (analogous to leaves) in a diffusion-limited manner due to low M surface area exposed to intercellular air space, with the functional role of Rubisco and glycine decarboxylase in distant M yet to be explained.

  19. Chemical Looping Combustion of Rice Husk

    OpenAIRE

    Rashmeet Singh Monga; Ganesh R. Kale

    2015-01-01

    A thermodynamic investigation of direct chemical looping combustion (CLC) of rice husk is presented in this paper. Both steam and CO2 are used for gasification within the temperature range of 500–1200˚C and different amounts of oxygen carriers. Chemical equilibrium model was considered for the CLC fuel reactor. The trends in product compositions of the fuel reactor, were determined. Rice husk gasification using 3 moles H2O and 0 moles CO2 per mole carbon (in rice husk) at 1 bar pr...

  20. Fertilizer and energy from grape-husks. Duenger und Energie aus Traubentrestern. Orujos de uva para energia y fertilizacion

    Energy Technology Data Exchange (ETDEWEB)

    Graefe, G.

    1983-08-01

    The research project of the bioenergy converter for grape husk humification belongs to the sector of utilization of biogenous wastes. It shows very clearly that it is possible to obtain high quality end products from so far neglected and annoying wastes just by applying innovative ideas. About 10 million tons of grape husk are annually produced in all countries of the earth together. So far almost nobody noticed that this is a very precious share of the annually produced biomass that was so far dumped on deposits. A method was developed which allows to process husks and convert them under aerobic conditions to high quality humus and in addition to generate energy.

  1. Ajout de phosphogypse à des mortiers à base de cendres volantes et filler calcaire Addition of phosphogypsum to blended mortars based on fly ash and limestone filler

    Directory of Open Access Journals (Sweden)

    Alami Talbi M.

    2012-09-01

    -ray diffraction and Infrared spectroscopy. Crystalline phases grow from the third day, and we note that the most common phases are: Portlandite Ca(OH2, CaCO3 calcite, ettringite Ca6Al2(SO43 (OH12 26H2O, Ca5(SiO42(OH2 and gypsum CaSO4, 2H2O but their percentages vary depending on the mixtures. Measuring the setting time of mortars shows that the beginning and end of setting are usually delayed in proportion to the addition of fly ash and phosphogypsum. The microstructure of materials was also studied by measuring the apparent permeability; the results show that the addition of phosphogypsum has contributed to a decrease in the permeability of the samples against fly ash has the opposite effect. The compressive strength of mortars shows concordant results, the strengths increase with the decrease in permeability.

  2. Elucidation of the effect of ionic liquid pretreatment on rice husk via structural analyses

    Directory of Open Access Journals (Sweden)

    Ang Teck

    2012-09-01

    Full Text Available Abstract Background In the present study, three ionic liquids, namely 1-butyl-3-methylimidazolium chloride ([BMIM]Cl, 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc, and 1-ethyl-3-methylimidazolium diethyl phosphate ([EMIM]DEP, were used to partially dissolve rice husk, after which the cellulose were regenerated by the addition of water. The aim of the investigation is to examine the implications of the ionic liquid pretreatments on rice husk composition and structure. Results From the attenuated total reflectance Fourier transform-infrared (ATR FT-IR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM results, the regenerated cellulose were more amorphous, less crystalline, and possessed higher structural disruption compared with untreated rice husk. The major component of regenerated cellulose from [BMIM]Cl and [EMIM]DEP pretreatments was cellulose-rich material, while cellulose regenerated from [EMIM]OAc was a matrix of cellulose and lignin. Cellulose regenerated from ionic pretreatments could be saccharified via enzymatic hydrolysis, and resulted in relatively high reducing sugars yields, whereas enzymatic hydrolysis of untreated rice husk did not yield reducing sugars. Rice husk residues generated from the ionic liquid pretreatments had similar chemical composition and amorphousity to that of untreated rice husk, but with varying extent of surface disruption and swelling. Conclusions The structural architecture of the regenerated cellulose and rice husk residues showed that they could be used for subsequent fermentation or derivation of cellulosic compounds. Therefore, ionic liquid pretreatment is an alternative in the pretreatment of lignocellulosic biomass in addition to the conventional chemical pretreatments.

  3. Ash sintering problems in the convection area - tests with additives in full scale; Asksintringsproblem i konvektionspaketet - tester med additiv i stor skala

    Energy Technology Data Exchange (ETDEWEB)

    Engvall, Klas [TPS Termiska Processer AB, Nykoeping (Sweden)

    2003-10-01

    The objective of the present study was to develop methods to reduce problems with ash deposits, hard to remove, on hot convective surfaces in a boiler. Tests were carried out in two boilers; a bubbling fluidised (FB) boiler with an effect of 30 MW in Falun and an 80 MW grate-fired boiler in Linkoeping. The work comprised a pre-study of fuels and deposition from previous investigations, tests with additives in large-scale in Falun and Linkoeping and, finally, evaluation of results. To sum up, the results demonstrate that addition of kaolin has a reducing effect on the chlorine content in the collected deposition in the tests in the FB boiler in Falun. The properties of the deposits formed were also altered in such a way that they were more easily removed from the heat transfer surface. The results from the tests in Linkoeping is unfortunately more difficult to interpret but point in some cases in the same direction as for Falun, for instance, similar alterations in the properties of the collected deposition was observed. Furthermore, the results also point at the importance of how the addition of the additive is carried out. In the case Linkoeping, the reason for the lower visible effects probably is due to a poor contact between the additive and the flue gas since most of the additive stays in the fixed bed on the grate. One important conclusion is that the additive most likely should be added directly above the bed, e.g., jointly with the secondary air.

  4. Laboratory Investigation on Compressive Strength and Micro-structural Features of Foamed Concrete with Addition of Wood Ash and Silica Fume as a Cement Replacement

    Directory of Open Access Journals (Sweden)

    Othuman Mydin M.A.

    2014-01-01

    Full Text Available Wood Ash (WA and Silica Fume (SF exhibit good cementation properties and have great potential as supplementary binder materials for the concrete production industry. This study will focus on enhancing the micro-structural formation and compressive strength of foamed concrete with the addition of WA and SF. A total of 3 mixes were prepared with the addition of WA and SF at various cement replacement levels by total binder weight. For this particular study, the combination of WA (5%, 10%, and 15% by binder weight and SF (5%, 10%, and 15% by binder weight were utilized as supplementary binder materials to produce foamed concrete mixes. As was made evident from micrographs obtained in the study, the improvement observed in the compressive strength of the foamed concrete was due to a significant densification in the microstructure of the cement paste matrix in the presence of WA and SF hybrid supplementary binders. Experimental results indicated that the combination of 15% SF and 5% WA by binder weight had a more substantial influence on the compressive strength of foamed concrete compared to the control mix. Furthermore, the addition of WA and SF significantly prolonged the setting times of the blended cement paste of the foamed concrete.

  5. Evaluation of a zirconium additive for the mitigation of molten ash formation during combustion of residual fuel oil

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    Florida Power & Light Company (FP&L) currently fires a residual fuel oil (RFO) containing catalyst fines, which results in a troublesome black aluminosilicate liquid phase that forms on heat-transfer surfaces, remains molten, and flows to the bottom of the boiler. When the unit is shut down for a scheduled outage, this liquid phase freezes to a hard black glass that damages the contracting waterwalls of the boiler. Cleaning the boiler bottom and repairing damaged surfaces increase the boiler downtime, at a significant cost to FP&L. The Energy & Environmental Research Center (EERC) proposed to perform a series of tests for FP&L to evaluate the effectiveness of a zirconium additive to modify the mechanism that forms this liquid phase, resulting in the formation of a dry refractory phase that may be easily handled during cleanup of the boiler.

  6. Comparison of saccharification and fermentation of steam exploded rice straw and rice husk.

    Science.gov (United States)

    Wood, Ian P; Cao, Huong-Giang; Tran, Long; Cook, Nicola; Ryden, Peter; Wilson, David R; Moates, Graham K; Collins, Samuel R A; Elliston, Adam; Waldron, Keith W

    2016-01-01

    Rice cultivation produces two waste streams, straw and husk, which could be exploited more effectively. Chemical pretreatment studies using rice residues have largely focussed on straw exploitation alone, and often at low substrate concentrations. Moreover, it is currently not known how rice husk, the more recalcitrant residue, responds to steam explosion without the addition of chemicals. The aim of this study has been to systematically compare the effects of steam explosion severity on the enzymatic saccharification and simultaneous saccharification and fermentation of rice straw and husk produced from a variety widely grown in Vietnam (Oryza sativa, cv. KhangDan18). Rice straw and husk were steam exploded (180-230 °C for 10 min) into hot water and washed to remove fermentation inhibitors. In both cases, pretreatment at 210 °C and above removed most of the noncellulosic sugars. Prolonged saccharification at high cellulase doses showed that rice straw could be saccharified most effectively after steam explosion at 210 °C for 10 min. In contrast, rice husk required more severe pretreatment conditions (220 °C for 10 min), and achieved a much lower yield (75 %), even at optimal conditions. Rice husk also required a higher cellulase dose for optimal saccharification (10 instead of 6 FPU/g DM). Hemicellulase addition failed to improve saccharification. Small pilot scale saccharification at 20 % (w/v) substrate loading in a 10 L high torque bioreactor resulted in similarly high glucose yields for straw (reaching 9 % w/v), but much less for husk. Simultaneous saccharification and fermentation under optimal pretreatment and saccharification conditions showed similar trends, but the ethanol yield from the rice husk was less than 40 % of the theoretical yield. Despite having similar carbohydrate compositions, pretreated rice husk is much less amenable to saccharification than pretreated rice straw. This is likely to attenuate its use as a biorefinery

  7. A study on flexural and water absorption of surface modified rice husk flour/E-glass/polypropylene hybrid composite

    Science.gov (United States)

    Rassiah, K.; Sin, T. W.; Ismail, M. Z.

    2016-10-01

    This work is to study the effects of rice husk (RH)/E-Glass (EG)/polypropylene (PP) hybrid composites in terms of flexural and water absorption properties. The tests conducted are the flexural test and also the water absorption test using two types of water: distilled and sea water. The hybrid composites are prepared with various ratios of fibre weight fractions and the rice husk is treated using 2% Sodium Hydroxide (NaOH) to improve interaction and adhesion between the non-polar matrix and the polar lignocellulosic fibres. It was found that the content of rice husk/E-Glass fillers affected the structural integrity and flexural properties of hybrid composites. In addition, a higher ratio of rice husk contributes to higher water absorption in the hybrid composites.

  8. The Fabrication and Characterization of PCL/Rice Husk Derived Bioactive Glass-Ceramic Composite Scaffolds

    OpenAIRE

    Farnaz Naghizadeh; Naznin Sultana; Mohammed Rafiq Abdul Kadir; Tengku Muzaffar Tengku Md Shihabudin; Rafaqat Hussain; Tunku Kamarul

    2014-01-01

    The present study was conducted to fabricate a 3D scaffold using polycaprolactone (PCL) and silicate based bioactive glass-ceramic (R-SBgC). Different concentrations of R-SBgC prepared from rice husk ash (RHA) were combined with PCL to fabricate a composite scaffold using thermally induced phase separation (TIPS) method. The products were then characterized using SEM and EDX. The results demonstrated that R-SBgC in PCL matrix produced a bioactive material which has highly porous structure wit...

  9. Addition of ash on drained forested peatlands in southern Sweden. Effects on forest production, fluxes of greenhouse gases and water chemistry; Tillfoersel av aska i tallskog paa dikad torvmark i soedra Sverige. Effekter paa skogsproduktion, avgaang av vaexthusgaser och vattenkemi

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem, Ulf; Jacobson, Staffan; Ring, Eva [Skogforsk, Uppsala (Sweden); Ernfors, Maria; Klemedtsson, Leif [Goeteborg Univ. (Sweden). Dept. of Plant and Environmental Sciences; Nilsson, Mats [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden)

    2006-04-15

    In Sweden, about one million tones of wood ashes are produced annually, of which about 250,000-300,000 tones originate from biofuels, e.g. forest residues. Some of the ashes produced are deposited today. One alternative use is bringing back the ashes to the forest, recycling the mineral nutrients and base compounds. In bioashes, most essential mineral nutrients for plants are included, except for N, which is gasified at combustion. On most mineral soils in Sweden, plant available nitrogen is the nutrient limiting tree growth. On organic soils, tree growth is usually increased after addition of phosphorous and potassium. Thus, there is a potential for increased forest production on peatlands after ash fertilization. This can be a profitable measure. Nutrient compensation after harvesting involve ash addition with quite low doses. This is especially important in peatlands after whole-tree harvesting in order to prevent nutrient deficiency and reduced tree growth. However, there is a need for better knowledge concerning other environmental effects before ash addition can be put into large-scale practice. The general objective of this project is to study the effects of wood-ash addition on forest production and some other environmental variables on drained, forested peatlands. The studies concern tree growth, emissions of greenhouse gases and water chemistry (ground water and run off). An important issue addressed was if an expected increased accumulation of carbon (CO{sub 2}) due to increased tree growth can compensate for an expected increased emission of greenhouse gases (e.g. CO{sub 2} and CH{sub 4}) from the peat. In addition, the very effective greenhouse gas laughing gas (N{sub 2}O), must be taken into consideration. In 2003, two field experiments were established in the county of Smaaland in southeast Sweden, where wood ashes from biofuels were applied. One experiment was designed as a randomized block experiment (273 Anderstorp) where effects on forest

  10. Addition of ash on drained forested peatlands in southern Sweden. Effects on forest production, fluxes of greenhouse gases and water chemistry; Tillfoersel av aska i tallskog paa dikad torvmark i soedra Sverige. Effekter paa skogsproduktion, avgaang av vaexthusgaser och vattenkemi

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem, Ulf; Ernfors, Maria; Jacobson, Staffan; Klemedtsson, Leif; Nilsson, Mats; Ring, Eva

    2006-04-15

    In Sweden, about one million tones of wood ashes are produced annually, of which about 250,000 - 300,000 tones originate from forest residues. Some of the ashes produced are deposited today. One alternative use is bringing back the ashes to the forest, recycling the mineral nutrients and base compounds. In bioashes, most essential mineral nutrients for plants are included, except for N, which is gasified at combustion. On most mineral soils in Sweden, plant available nitrogen is the nutrient limiting tree growth. On organic soils, tree growth is usually increased after addition of phosphorous and potassium. Thus, there is a potential for increased forest production on peatlands after ash fertilization. This can be a profitable measure. Nutrient compensation after harvesting involve ash addition with quite low doses. This is especially important in peatlands after whole-tree harvesting in order to prevent nutrient deficiency and reduced tree growth. However, there is a need for better knowledge concerning other environmental effects before ash addition can be put into large-scale practice. The general objective of this project is to study the effects of wood-ash addition on forest production and some other environmental variables on drained, forested peatlands. The studies concern tree growth, emissions of greenhouse gases and water chemistry (ground water and run off). An important issue addressed was if an expected increased accumulation of carbon (CO{sub 2}) due to increased tree growth can compensate for an expected increased emission of greenhouse gases (e.g. CO{sub 2} and CH{sub 4}) from the peat. In addition, the very effective greenhouse gas laughing gas (N2O), must be taken into consideration. In 2003, two field experiments were established in the county of Smaaland in south Sweden, where wood ashes from biofuels were applied. One experiment was designed as a randomized block experiment where effects on forest production and greenhouse gases (CO{sub 2}, CH

  11. The effect of chickpea (Cicer arietinim) husk on the properties of cracker biscuits

    OpenAIRE

    Bose, D; Shams-Ud-Din, M.

    2010-01-01

    Chickpea (Cicer arietinim) husk was extracted by non-alkaline aqueous extraction process. The residual extracted husk was dried in a cabinet drier and finally ground. Both fresh husk and processed husk were analyzed for their composition. The processed husk (extracted ground husk) was incorporated into formulations of cracker biscuits at 0- 20% replacement levels of wheat flour and baking functionalities were evaluated. The studies on the effects of processed husk on biscuit’s qualities showe...

  12. Use of palm bunch ash-based mineral water in a geriatric patient ...

    African Journals Online (AJOL)

    Optimal water, electrolyte and acid-base balance are of great importance in the management of human disease generally. Palm bunch ash (PBA) is obtained by complete combustion of the husk of Elaeis guineensis (oil palm tree). PBA-based mineral water is innocuous, safe and cost-effective for the treatment of systemic ...

  13. Rice Husk Filled Polymer Composites

    Directory of Open Access Journals (Sweden)

    Reza Arjmandi

    2015-01-01

    Full Text Available Natural fibers from agricultural wastes are finding their importance in the polymer industry due to the many advantages such as their light weight, low cost and being environmentally friendly. Rice husk (RH is a natural sheath that forms around rice grains during their growth. As a type of natural fiber obtained from agroindustrial waste, RH can be used as filler in composites materials in various polymer matrices. This review paper is aimed at highlighting previous works of RH filled polymer composites to provide information for applications and further research in this area. Based on the information gathered, application of RH filled composites as alternative materials in building and construction is highly plausible with both light weight and low cost being their main driving forces. However, further investigations on physical and chemical treatment to further improve the interfacial adhesion with polymeric matrix are needed as fiber-polymer interaction is crucial in determining the final composite properties. Better understanding on how the used polymer blends as the matrix and secondary fillers may affect the properties would provide interesting areas to be explored.

  14. Anti-inflammatory effects of Zea mays L. husk extracts.

    Science.gov (United States)

    Roh, Kyung-Baeg; Kim, Hyoyoung; Shin, Seungwoo; Kim, Young-Soo; Lee, Jung-A; Kim, Mi Ok; Jung, Eunsun; Lee, Jongsung; Park, Deokhoon

    2016-08-19

    Zea mays L. (Z. mays) has been used for human consumption in the various forms of meal, cooking oil, thickener in sauces and puddings, sweetener in processed food and beverage products, bio-disel. However, especially, in case of husk extract of Z. mays, little is known about its anti-inflammatory effects. Therefore, in this study, the anti-inflammatory effects of Z. mays husk extract (ZMHE) and its mechanisms of action were investigated. The husks of Z. Mays were harvested in kangwondo, Korea. To assess the anti-inflammatory activities of ZMHE, we examined effects of ZMHE on nitric oxide (NO) production, and release of soluble intercellular adhesion molecule-1 (sICAM-1) and eotaxin-1. The expression level of inducible nitric oxide synthase (iNOS) gene was also determined by Western blot and luciferase reporter assays. To determine its mechanisms of action, a luciferase reporter assay for nuclear factor kappa B (NF-kB) and activator protein-1 (AP-1) was introduced. ZMHE inhibited lipopolysaccharide (LPS)-induced production of NO in RAW264.7 cells. In addition, expression of iNOS gene was reduced, as confirmed by Western blot and luciferase reporter assays. Effects of ZMHE on the AP-1 and NF-kB promoters were examined to elucidate the mechanism of its anti-inflammatory activity. Activation of AP-1 and NF-kB promoters induced by LPS was significantly reduced by ZMHE treatment. In addition, LPS-induced production of sICAM-1 and IL-4-induced production of eotaxin-1 were all reduced by ZMHE. Our results indicate that ZMHE has anti-inflammatory effects by downregulating the expression of iNOS gene and its downregulation is mediated by inhibiting NF-kB and AP-1 signaling.

  15. Covalent immobilization of oxylipin biosynthetic enzymes on nanoporous rice husk silica for production of cis(+)-12-oxophytodienoic acid.

    Science.gov (United States)

    Le, Thu Bao; Han, Chong Soo; Cho, Kyoungwon; Han, Oksoo

    2017-09-11

    Soybean lipoxygenase, recombinant rice allene oxide synthase-1 and rice allene oxide cyclase were covalently immobilized on nanoporous rice husk silica using two types of linkers: glutardialdehyde and polyethylene glycol. The immobilization efficiency achieved using glutardialdehyde-linked rice husk silica was higher than that achieved using polyethylene glycol-linked rice husk silica (50-92% and 25-50%, respectively). Immobilization on both types of matrices significantly decreased the specific activities of the immobilized enzymes. Solid-phase reaction yields of the enzymes were determined relative to the yields observed for the solution-phase reactions. Yields of the solid-phase reactions catalyzed by immobilized soybean lipoxygenase, rice allene oxide synthase-1, and rice allene oxide cyclase ranged from 50% to 230% and were dependent on both the enzymes and linkers used. Production of cis(+)-12-oxophytodienoic acid from α-linolenic acid by consecutive reactions using all three enzymes in a co-immobilization system resulted in 83.6% and 65.1% yields on glutardialdehyde-linked and epichlorohydrin-polyethylene glycol-linked rice husk silica, respectively. Our results suggest that immobilization of biosynthetic enzymes of the octadecanoid pathway on rice husk silica may be an efficient method for the in vitro production of oxylipins. Additionally, enzyme immobilizations on rice husk silica matrices may be more broadly applicable for producing physiologically important compounds in other biosynthetic pathways.

  16. Major gaseous and PAH emissions from a fluidized-bed combustor firing rice husk with high combustion efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Janvijitsakul, Kasama; Kuprianov, Vladimir I. [School of Manufacturing Systems and Mechanical Engineering, Sirindhorn International Institute of Technology, Thammasat University, P.O. Box 22, Thammasat Rangsit Post Office, Pathum Thani 12121 (Thailand)

    2008-08-15

    This experimental work investigated major gaseous (CO and NO{sub x}) and PAH emissions from a 400 kW{sub th} fluidized-bed combustor with a cone-shaped bed (referred to as 'conical FBC') firing rice husk with high, over 99%, combustion efficiency. Experimental tests were carried out at the fuel feed rate of 80 kg/h for different values of excess air (EA). As revealed by the experimental results, EA had substantial effects on the axial CO and NO{sub x} concentration profiles and corresponding emissions from the combustor. The concentration (mg/kg-ash) and specific emission ({mu}g/kW h) of twelve polycyclic aromatic hydrocarbons (PAHs), acenaphthylene, fluorene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene and indeno[1,2,3-cd]pyrene, were quantified in this work for different size fractions of ash emitted from the conical FBC firing rice husk at EA = 20.9%. The total PAHs emission was found to be predominant for the coarsest ash particles, due to the effects of a highly developed internal surface in a particle volume. The highest emission was shown by acenaphthylene, 4.1 {mu}g/kW h, when the total yield of PAHs via fly ash was about 10 {mu}g/kW h. (author)

  17. Simultaneous SO{sub 2} and NO removal using sorbents derived from rice husks: An optimisation study

    Energy Technology Data Exchange (ETDEWEB)

    L.C. Lau; K.T. Lee; A.R. Mohamed [Universiti Sains Malaysia, Pulau Pinang (Malaysia). School of Chemical Engineering

    2011-05-15

    In this study, rice husk-derived ash (RHA) was hydrated with CaO and then impregnated with copper to synthesize a sorbent that was subsequently tested for its capacity in simultaneous removal of SO{sub 2} and NO from a simulated flue gas. The effect of various sorbent preparation parameters, including copper loading, RHA/CaO ratio, hydration period and NaOH concentration, on the desulphurisation/denitrification capacity of the sorbents was studied using Design-Expert Version 6.0.6 software. Specifically, central composite design (CCD) coupled with response surface method (RSM) was used. The individual parameters that were found to significantly affect the sorbent capacity were RHA/CaO ratio and NaOH concentration. In addition, the interactive effect between RHA/CaO ratio, hydration period and NaOH concentration was also found to have a significant effect on the sorbent activity. The preparation condition for optimal sorbent activity was found to be CuO loading of 3.0%, RHA/CaO ratio of 1.4, hydration period of 20.0 h and NaOH concentration of 0.2 M. Characterisation of the sorbent was performed using scanning electron microscopy (SEM), X-ray diffraction (XRD) and nitrogen adsorption-desorption method to describe the effect of the sorbent preparation parameters on its desulphurisation/denitrification activity. 23 refs., 3 figs., 5 tabs.

  18. Characterization of fly ash from bio and municipal waste

    DEFF Research Database (Denmark)

    Lima, Ana T.; Ottosen, Lisbeth M.; Pedersen, Anne Juul

    2008-01-01

    Four different fly ashes are characterized in the present paper. The ashes differ in the original fuel type and were sampled at distinct plants. The investigation includes two different ashes from municipal solid waste incineration (with and without sorbents addition), a straw ash and an ash from...... potentiality to be valorized. The main conclusion of this paper regards fly ash’s profound dissimilarity, where each ash should be studied separately....

  19. Cementing Material From Rice Husk-Broken Bricks-Spent Bleaching Earth-Dried Calcium Carbide Residue

    Directory of Open Access Journals (Sweden)

    Muthengia Jackson Washira

    2012-10-01

    Full Text Available A cementious material, coded CSBR (Carbide residue Spent bleaching earth Broken bricks and Rice husks, was made from dried calcium carbide residue (DCCR and an incinerated mix of rice husks (RH, broken bricks (BB and spent bleaching earth (SBE. Another material, coded SBR (Spent bleaching earth Broken bricks and Rice husk ash, was made from mixing separately incinerated RH, SBE and ground BB in the same ash ratio as in CSBR. When CSBR was inter-ground with Ordinary Portland Cement (OPC, it showed a continued decrease in Ca(OH2 in the hydrating cement as a function of curing time and replacement levels of the cement. Up to 45 % replacement of the OPC by CSBR produced a Portland pozzolana cement (PPC material that passed the relevant Kenyan Standard. Incorporation of the CSBR in OPC reduces the resultant calcium hydroxide from hydrating Portland cement. The use of the waste materials in production of cementitious material would rid the environment of wastes and lead to production of low cost cementitious material.

  20. Rice Husk Silica-Derived Nanomaterials for Battery Applications: A Literature Review.

    Science.gov (United States)

    Shen, Yafei

    2017-02-08

    Silica-rich rice husk (RH) is an abundant and sustainable agricultural waste. The recovery of value-added products from RH or its ash to explore an economic way for the valorization of agricultural wastes has attracted wide attention. For instance, RH can be converted to biofuels and biochars simultaneously via thermochemical processes. In general, the applications of RH biochars include soil remediation, pollutant removal, silicon battery materials, and so forth. This review concludes recent progress in the synthesis of RH-derived silicon materials for lithium-ion battery (LIB) applications. Silica nanomaterials produced from RH are initially discussed. RH amorphous silica can also be fabricated to crystal silicon used for battery materials via widely used magnesiothermic reduction. However, the RH-derived Si nanoparticles suffer from a low Coulombic efficiency in the initial charge/discharge and limited cycle life as anode materials due to high surface reactions and low thermodynamic stability. The synthesis of Si materials with nano/microhierarchical structure would be an ideal way to improve their electrochemical performances. Embedding nano-Si into 3D conductive matrix is an effective way to improve the structural stability. Among the Si/carbon composite materials, carbon nanotubdes (CNTs) are a promising matrix due to the wired morphology, high electronic conductivity, and robust structure. Additionally, CNTs can easily form 3D cross-linked conducting networks, ensuring effective electron transportation among active particles. Si nanomaterials with microhierarchical structures in which CNTs are tightly intertwined between the RH-derived Si nanoparticles have been proven to be ideal LIB anode materials.

  1. Energetic characterization of the husk of the castor bean fruits of the variety Guarani

    Energy Technology Data Exchange (ETDEWEB)

    Teramoto, Erico Tadao; Sousa, Frederico Faula; Castro Neto, Pedro [Universidade Federal de Lavras (DEG/UFLA), MG (Brazil). Dept. de Engenharia; Trugilho, Paulo Fernando [Universidade Federal de Lavras (DCF/UFLA), MG (Brazil). Dept. de Ciencias Florestais; Fraga, Antonio Carlos [Universidade Federal de Lavras (DAG/UFLA), MG (Brazil). Dept. de Agricultura; Nunes, Ramon Rachide [Universidade Federal de Lavras (DAG/UFLA), MG (Brazil). Dept. de Quimica

    2008-07-01

    The knowledge of the physical properties and of the calorific power and of the immediate chemical analysis certain products are interesting for the development of new technologies and equipment for your processing or use as fuel. This way, due to the scarce readiness of referring works for the husk of the castor bean fruits, the present study seeks complemental the available data in the literature. For such were certain the following properties of the husk of the castor bean fruits of variety Guarani: angle of repose, hectolitre weigh, moisture, ash content, volatile material content, fixed carbon content and superior calorific power and inferior calorific power. The following values were found: 42 deg for the angle of repose, 13.92 kg for the hectolitre weight, 4223.19 kcal/kg for the superior calorific power, 3829.92 kcal/kg for the inferior calorific power, 8.21% for the moisture, 9.86% for the ash content, 73.67% for the volatile material content and 8.26% for the fixed carbon content. (author)

  2. Effect of addition of sugar cane biomass ash in properties of fresh state in cement slurries for oil wells; Efeito da adicao de cinza de biomassa de cana-de-acucar nas propriedades no estado fresco de pastas de cimento para pocos de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Galvao, Lornna L.A.; Santos, Herculana T.; Souza, Pablo Diego Pinheiro; Freitas, Julio Cezar Oliveira [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil); Nascimento, Julio Cesar S. [Universidade Federal da Bahia (UFBA), BA (Brazil); Amorim, Natalia M.M. [Universidade Potiguar (UNP), RN (Brazil); Martinell, Antonio E. [Mcgill University (MCGILL) (Canada); Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil)

    2012-07-01

    Recent studies have shown that ashes from biomass, in particular those generated by the alcohol industry have pozzolanic activity and can replace cement in many applications, reducing the consumption of cement and, consequently, the environmental impact caused by the production of this material. The present work evaluated the behavior of ash sugarcane biomass partially replacing Portland cement in concentrations of 10, 20 and 40% BWOC in oil well slurries. The results of rheology, thickening time and stability showed that the addition of 40% of biomass ash in oil well slurries significantly improves their properties, enabling the replacement of cement by ash. (author)

  3. Treatment of fly ash for use in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Boxley, Chett [Park City, UT

    2012-05-15

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with a quantity of spray dryer ash (SDA) and water to initiate a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 40%, and in some cases less than 20%, of the foam index of the untreated fly ash. An optional alkaline activator may be mixed with the fly ash and SDA to facilitate the geopolymerization reaction. The alkaline activator may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  4. Review: Potential Strength of Fly Ash-Based Geopolymer Paste with Substitution of Local Waste Materials with High-Temperature Effect

    Science.gov (United States)

    Subekti, S.; Bayuaji, R.; Darmawan, M. S.; Husin, N. A.; Wibowo, B.; Anugraha, B.; Irawan, S.; Dibiantara, D.

    2017-11-01

    This research provided an overview of the potential fly ash based geopolymer paste for application in building construction. Geopolymer paste with various variations of fly ash substitution with local waste material and high-temperature influence exploited with the fresh and hardened condition. The local waste material which utilized for this study were sandblasting waste, carbide waste, shell powder, bagasse ash, rice husk and bottom ash. The findings of this study indicated that fly-based geopolymer paste with local waste material substitution which had high-temperature influence ash showed a similar nature of OPC binders potentially used in civil engineering applications.

  5. Electrostatic separation of mineral and vegetal powders with a custom built corona separator: application to biorefinery of rice husk

    Science.gov (United States)

    Rajaonarivony, Rova Karine; Rouau, Xavier; Dascalescu, Lucien; Mayer-Laigle, Claire

    2017-06-01

    In a dry biorefinery scheme, the separation of plant materials into powders rich in the constituents of interest is a crucial step. In recent years, electrostatic separation of agri-resources has sparked a growing interest for its potentialities, but optimization efforts remain to be done especially in case of fine powders. In this study a custom-designed corona-electrostatic separator has been built and its usage for the separation of mineral (ash from rice husk) and vegetal powders (cellulose fibers) with different particle size distributions has been studied. First, the powders have been characterized by their electric charge decay curves and their behaviour on the separator was studied. At a second time, separation tests have been carried out with blends of these two powders, and with native, finely ground, rice husk powder (constituted of both mineral and vegetal particles). In each case, the efficiency of the process was evaluated.

  6. Characterization of materials formed by rice husk for construction

    Science.gov (United States)

    Portillo-Rodríguez, A. M.

    2013-11-01

    This review article delves into the use of agro-industrial wastes, which in construction field provides alternatives for environmental problems with the use of them. This fact enables development and lower costs for new options in the brick, cluster, mortar and concrete industry, what represents benefits for environment, housing and generally everything related to construction, looking for sustainability. For that reason a literature review is made to support the theme focusing on the use of rice husk in its natural, ground or ash state for manufacturing elements with clay masonry, precast and optimization of concrete and mortars. The technique used is based on scientific articles and researches found in reliable databases that were analyzed and integrated into a synthesized structure, which summarized the objectives, analysis processes, the physical and mechanical properties and finally the results. The conclusions are focused on potentiality of elements production in the construction development based on the high effectiveness like thermal insulation, low density and various benefits offered by high silica content pozzolanic properties, etc.

  7. Assessment of hazelnut husk as a lignocellulosic feedstock for the production of fermentable sugars and lignocellulolytic enzymes.

    Science.gov (United States)

    Pinar, Orkun; Karaosmanoğlu, Kübra; Sayar, Nihat Alpagu; Kula, Ceyda; Kazan, Dilek; Sayar, Ahmet Alp

    2017-12-01

    The present work focuses firstly on the evaluation of the effect of laccase on enzymatic hydrolysis of hazelnut husk which is one of the most abundant lignocellulosic agricultural residues generated in Turkey. In this respect, the co-enzymatic treatment of hazelnut husk by cellulase and laccase, without a conventional pretreatment step is evaluated. Using 2.75 FPU/g substrate (40 g/L substrate) and a ratio of 131 laccase U/FPU achieved the highest reducing sugars concentration. Gas chromatography mass spectrometry confirmed that the hydrolysate was composed of glucose, xylose, mannose, arabinose and galactose. The inclusion of laccase in the enzyme mixture [carboxymethyl cellulase (CMCase) and β-glucosidase] increased the final glucose content of the reducing sugars from 20 to 50%. Therefore, a very significant increase in glucose content of the final reducing sugars concentration was obtained by laccase addition. Furthermore, the production of cellulases and laccase by Pycnoporus sanguineus DSM 3024 using hazelnut husk as substrate was also investigated. Among the hazelnut husk concentrations tested (1.5, 6, 12, 18 g/L), the highest CMCase concentration was obtained using 12 g/L husk concentration on the 10th day of fermentation. Besides CMCase, P. sanguineus DSM 3024 produced β-glucosidase and laccase using hazelnut husk as carbon source. In addition to CMCase and β-glucosidase, the highest laccase activity measured was 2240 ± 98 U/L (8.89 ± 0.39 U/mg). To the best of our knowledge, this is the first study to report hazelnut husk hydrolysis in the absence of pretreatment procedures.

  8. Effect of sintering temperature variations on fabrication of 45S5 bioactive glass-ceramics using rice husk as a source for silica.

    Science.gov (United States)

    Leenakul, Wilaiwan; Tunkasiri, Tawee; Tongsiri, Natee; Pengpat, Kamonpan; Ruangsuriya, Jetsada

    2016-04-01

    45S5 bioactive glass is a highly bioactive substance that has the ability to promote stem cell differentiation into osteoblasts--the cells that create bone matrix. The aim of this work is to analyze physical and mechanical properties of 45S5 bioactive glass fabricated by using rice husk ash as its silica source. The 45S5 bioactive glass was prepared by melting the batch at 1300 °C for 3h. The samples were sintered at different temperatures ranging from 900 to 1050 °C with a fixed dwell-time of 2h. The phase transitions, density, porosity and microhardness values were investigated and reported. DTA analysis was used to examine the crystallization temperatures of the glasses prepared. We found that the sintering temperature had a significant effect on the mechanical and physical properties of the bioactive glass. The XRD showed that when the sintering temperature was above 650 °C, crystallization occurred and bioactive glass-ceramics with Na2Ca2Si3O9, Na2Ca4(PO4)2SiO4 and Ca3Si2O7 were formed. The optimum sintering temperature resulting in maximum mechanical values was around 1050 °C, with a high density of 2.27 g/cm(3), 16.96% porosity and the vicker microhardness value of 364HV. Additionally, in vitro assay was used to examine biological activities in stimulated body fluid (SBF). After incubation in SBF for 7 days, all of the samples showed formations of apatite layers indicating that the 45S5 bioactive glasses using rice husk as a raw material were also bioactive. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Ash addition after whole-tree harvesting on fertile sites in southern Sweden Establishment of two field trials; Askaaterfoering efter skogsbraensleuttag paa boerdig skogsmark i soedra Sverige Anlaeggning av tvaa faeltfoersoek

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem, Ulf; Hoegbom, Lars; Jacobson, Staffan; Lundstroem, Hagos; Ring, Eva

    2012-02-15

    In Sweden, the Swedish Forest Agency recommend ash recycling after whole-tree harvest (WTH), i.e. the whole tree above the stump is harvested. If this recommendation is complied, ash recycling will become a quite extensive forestry practice. To gain more knowledge regarding effects of ash on tree growth, storage of carbon (C) and nitrogen (N) in the upper soil, and soil-water chemistry, two field experiments were established. The experimental design was a randomized block design. Both experiments were installed on quite fertile sites in southern Sweden. On fertile sites (C/N less than 30), ash addition is hypothesized to increase tree growth, reduce the storage of C and N in the upper soil, and increase the concentrations of nitrate in soil water. One experiment (291 Guvarp) was established on a recently harvested clear cut. The sample plots were soil scarified by disc trenching and planted with Norway spruce (Picea abies L. Karst.) seedlings. Seedling height was measured at planting, and, two months later, seedling survival and height growth in 2011 was recorded. The other experiment (290 Bala) was located to a Norway spruce stand that was thinned by WTH. The initial registration and sampling comprised stand data and sampling of the upper soil (FH-layer). In addition, suction cups were installed at 50 cm depth for sampling of soil water. The experiments were designed for long-term monitoring, comprising several decades. For most of the variables registered, data did not show any significant differences among means for the plots representing different treatments. Pre-treatment data for individual plots showed acceptable comparability among plots within the blocks, which is a good starting point for detecting future changes caused by the treatments

  10. Recycling rice husks for high-capacity lithium battery anodes.

    Science.gov (United States)

    Jung, Dae Soo; Ryou, Myung-Hyun; Sung, Yong Joo; Park, Seung Bin; Choi, Jang Wook

    2013-07-23

    The rice husk is the outer covering of a rice kernel and protects the inner ingredients from external attack by insects and bacteria. To perform this function while ventilating air and moisture, rice plants have developed unique nanoporous silica layers in their husks through years of natural evolution. Despite the massive amount of annual production near 10(8) tons worldwide, so far rice husks have been recycled only for low-value agricultural items. In an effort to recycle rice husks for high-value applications, we convert the silica to silicon and use it for high-capacity lithium battery anodes. Taking advantage of the interconnected nanoporous structure naturally existing in rice husks, the converted silicon exhibits excellent electrochemical performance as a lithium battery anode, suggesting that rice husks can be a massive resource for use in high-capacity lithium battery negative electrodes.

  11. Evaluation of the occluded carbon within husk phytoliths of 35 rice cultivars

    Science.gov (United States)

    Sun, Xing; Liu, Qin; Gu, Jie; Chen, Xiang; Zhu, Keya

    2016-12-01

    Rice is a well-known silicon accumulator. During its periods of growth, a great number of phytoliths are formed by taking up silica via the plant roots. Concurrently, carbon in those phytoliths is sequestrated by a mechanism of long-term biogeochemical processes within the plant. Phytolith occluded C (PhytOC) is very stable and can be retained in soil for longer than a millennium. In this study, we evaluated the carbon biosequestration within the phytoliths produced in rice seed husks of 35 rice cultivars, with the goal of finding rice cultivars with relatively higher phytolith carbon sequestration efficiencies. The results showed that the phytolith contents ranged from 71.6 mg•g‒1 to 150.1 mg•g‒1, and the PhytOC contents ranged from 6.4 mg•g‒1 to 38.4 mg•g‒1, suggesting that there was no direct correlation between the PhytOC content and the content of rice seed husk phytoliths ( R = 0.092, p>0.05). Of all rice cultivars, six showed a higher carbon sequestration efficiency in phytolith seed husks. Additionally, the carbon biosequestration within the rice seed husk phytoliths was approximately 0.45‒3.46 kg-e-CO2•ha‒1•yr‒1. These rates indicate that rice cultivars are a potential source of carbon biosequestration which could contribute to the global carbon cycle and climate change.

  12. Physico chemical evaluation of coffee husk, wastes of enset (Enset ...

    African Journals Online (AJOL)

    Physico chemical evaluation of coffee husk, wastes of enset (Enset ventricosum), vegetable and khat (Catha edulis) through vermicomposting employing an epigeic earthworm Dendrobaena veneta (Rosa, 1886)

  13. Synthesis of geopolymer from biomass-coal ash blends

    Science.gov (United States)

    Samadhi, Tjokorde Walmiki; Wulandari, Winny; Prasetyo, Muhammad Iqbal; Fernando, Muhammad Rizki; Purbasari, Aprilina

    2017-09-01

    Geopolymer is an environmentally attractive Portland cement substitute, owing to its lower carbon footprint and its ability to consume various aluminosilicate waste materials as its precursors. This work describes the development of geopolymer formulation based on biomass-coal ash blends, which is predicted to be the prevalent type of waste when biomass-based thermal energy production becomes mainstream in Indonesia. The ash blends contain an ASTM Class F coal fly ash (FA), rice husk ash (RHA), and coconut shell ash (CSA). A mixture of Na2SiO3 and concentrated KOH is used as the activator solution. A preliminary experiment identified the appropriate activator/ash mass ratio to be 2.0, while the activator Na2SiO3/KOH ratio varies from 0.8 to 2.0 with increasing ash blend Si/Al ratio. Both non-blended FA and CSA are able to produce geopolymer mortars with 7-day compressive strength exceeding the Indonesian national SNI 15-2049-2004 standard minimum value of 2.0 MPa stipulated for Portland cement mortars. Ash blends have to be formulated with a maximum RHA content of approximately 50 %-mass to yield satisfactory 7-day strength. No optimum ash blend composition is identified within the simplex ternary ash blend compositional region. The strength decreases with Si/Al ratio of the ash blends due to increasing amount of unreacted silicate raw materials at the end of the geopolymer hardening period. Overall, it is confirmed that CSA and blended RHA are feasible raw materials for geopolymer production..

  14. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    2013-01-08

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  15. Treatment of fly ash for use in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Boxley, Chett [Park City, UT; Akash, Akash [Salt lake City, UT; Zhao, Qiang [Natick, MA

    2012-05-08

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  16. Fabrication and characterization of rice husk and coconut shell charcoal based bio-briquettes as alternative energy source

    Science.gov (United States)

    Yuliah, Y.; Kartawidjaja, M.; Suryaningsih, S.; Ulfi, K.

    2017-05-01

    Rice husk and coconut shell have been disposed or burned as waste. As biomass, both of materials are the potential sources of carbon which can be utilized as alternative energy sources. The energy content can be exploited more intensively when packaged in a brief and convenient. In this work, the mixtures of rice husks and coconut shells charcoal were prepared as briquettes. After going through the carbonization process, several measurements have been taken to find out the factors that determine the value of heat energy contains by each component of the charcoals. The basic ingredients briquettes prepared from rice husk and coconut shell charcoal with varying composition and addition of tapioca starch gradually as adhesive material to obtain briquettes in solid with the maximum heat energy content. After going through pressing and drying process, the briquettes with 50:50 percent of composition and the 6% addition of adhesive was found has the highest heat energy content, equal to 4966 cal/g.

  17. Catalytic hydrothermal upgradation of wheat husk.

    Science.gov (United States)

    Singh, Rawel; Bhaskar, Thallada; Dora, Sambha; Balagurumurthy, Bhavya

    2013-12-01

    Catalytic hydrothermal upgradation of wheat husk was performed at 280°C for 15 min in the presence of alkaline catalysts (KOH and K2CO3). The effect of alkaline catalysts on the yield of bio-oil products and composition of bio-oils obtained were discussed. Total bio-oil yield (31%) comprising of bio-oil1 (ether fraction) and bio-oil2 (acetone fraction) was maximum with K2CO3 solution. Powder XRD (X-ray diffraction) analysis of wheat husk as well as bio-residue samples show that the peaks due to cellulose, hemicellulose and lignin become weak in bio-residue samples which suggest that these components have undergone hydrolytic cleavage/decomposition. The FTIR spectra of bio-oils indicate that the lignin in the wheat husk samples was decomposed to low molecular weight phenolic compounds. (1)H Nuclear Magnetic Resonance (NMR) spectrum of bio-oil1 shows more than 50% of the protons resonate in the up field region from 0.5 ppm to 3.0 ppm. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Bioethanol produced from Moringa oleifera seeds husk

    Science.gov (United States)

    Ali, E. N.; Kemat, S. Z.

    2017-06-01

    This paper presents the potential of bioethanol production from Moringa oleifera seeds husk which contains lignocellulosic through Simultaneous Saccharification and Fermentation (SSF) process by using Saccharomyces cerevisiae. This paper investigates the parameters which produce optimum bioethanol yield. The husk was hydrolyzed using NaOH and fermented using Saccharomyces cerevisiae yeast. Batch fermentation was performed with different yeast dosage of 1, 3, and 5 g/L, pH value was 4.5, 5.0 and 5.5, and fermentation time of 3, 6, 9 and 12 hours. The temperature of fermentation process in incubator shaker is kept constant at 32ºC. The samples are then filtered using a 0.20 μm nylon filter syringe. The yield of bioethanol produced was analysed using High Performance Liquid Chromatography (HPLC). The results showed that the highest yield of 29.69 g/L was obtained at 3 hours of fermentation time at pH of 4.5 and using 1g/L yeast. This research work showed that Moringa oleifera seeds husk can be considered to produce bioethanol.

  19. Production of Nanocellulose from Rice Husk

    Directory of Open Access Journals (Sweden)

    Shaghayegh Rezanezhad

    2013-11-01

    Full Text Available In this work, nanocellulose was produced from rice husk, as a lignocellulosic waste of rice. Initially, purified cellulose was produced with chemo-mechanical and soda-anthraquinone (soda/AQ pulping and bleaching. The purified cellulose was then sonicated for 15 min using an ultrasonic processor, resulted in nanocellulose. The nanocellulose obtained by sonification has been characterized by atomic force microscopy (AFM, X-ray diffraction (XRD and thermogravimetric analysis (TGA. Diameter of nanocellulose from rice husk by chemical method was 30-40 nm and that of produced by soda-AQ pulping method were 10-20 nm. The nanocellulose crystallinity for chemical method obtained 60% and for that of produced with soda-AQ pulping method was 66%. The degradation onset temperature for nanocellulose from rice husk by chemical method was 165°C and that of produced with soda-AQ pulping method were 188°c. The thermal behaviors of nanocellulose and purified cellulose were almost the same, suggesting the ultrasonic treatment had minor effect on the thermal decomposition of the nanocellulose.

  20. Asymmetric Ashes

    Science.gov (United States)

    2006-11-01

    that oscillate in certain directions. Reflection or scattering of light favours certain orientations of the electric and magnetic fields over others. This is why polarising sunglasses can filter out the glint of sunlight reflected off a pond. When light scatters through the expanding debris of a supernova, it retains information about the orientation of the scattering layers. If the supernova is spherically symmetric, all orientations will be present equally and will average out, so there will be no net polarisation. If, however, the gas shell is not round, a slight net polarisation will be imprinted on the light. This is what broad-band polarimetry can accomplish. If additional spectral information is available ('spectro-polarimetry'), one can determine whether the asymmetry is in the continuum light or in some spectral lines. In the case of the Type Ia supernovae, the astronomers found that the continuum polarisation is very small so that the overall shape of the explosion is crudely spherical. But the much larger polarization in strongly blue-shifted spectral lines evidences the presence, in the outer regions, of fast moving clumps with peculiar chemical composition. "Our study reveals that explosions of Type Ia supernovae are really three-dimensional phenomena," says Dietrich Baade. "The outer regions of the blast cloud is asymmetric, with different materials found in 'clumps', while the inner regions are smooth." "This study was possible because polarimetry could unfold its full strength thanks to the light-collecting power of the Very Large Telescope and the very precise calibration of the FORS instrument," he adds. The research team first spotted this asymmetry in 2003, as part of the same observational campaign (ESO PR 23/03 and ESO PR Photo 26/05). The new, more extensive results show that the degree of polarisation and, hence, the asphericity, correlates with the intrinsic brightness of the explosion. The brighter the supernova, the smoother, or less clumpy

  1. Coffee husks: - A possible wood substitute in the particleboard industry

    African Journals Online (AJOL)

    Coffee husks, a waste by-product from coffee processing has been used as particles with hydrolysed tannin and urea formaldehyde as binders to make homogenous coffee husks particleboards. The resulting particleboards were subjected to physical and mechanical tests and a comparison made with the existing ...

  2. Equine poisoning by coffee husk (Coffea arabica L.

    Directory of Open Access Journals (Sweden)

    Delfiol Diego Jose Z

    2012-01-01

    Full Text Available Abstract Background In Brazil, coffee (Coffea arabica husks are reused in several ways due to their abundance, including as stall bedding. However, field veterinarians have reported that horses become intoxicated after ingesting the coffee husks that are used as bedding. The objective of this study was to evaluate whether coffee husk consumption causes intoxication in horses. Results Six horses fed coast cross hay ad libitum were given access to coffee husks and excitability, restlessness, involuntary muscle tremors, chewing movements and constant tremors of the lips and tongue, excessive sweating and increased respiration and heart rates were the most evident clinical signs. Caffeine levels were measured in the plasma and urine of these horses on two occasions: immediately before the coffee husks were made available to the animals (T0 and at the time of the clinical presentation of intoxication, 56 h after the animals started to consume the husks (T56. The concentrations of caffeine in the plasma (p Conclusions It was concluded that consumption of coffee husks was toxic to horses due to the high levels of caffeine present in their composition. Therefore, coffee husks pose a risk when used as bedding or as feed for horses.

  3. Comparative Study Of Asbestos And Rice Husk As Roofing Materials

    African Journals Online (AJOL)

    The need to get a replacement for asbestos as a roofing material cannot be overemphasized. Therefore, the researcher in this study critically analyses the characteristics of rice husk as compared to the characteristics of asbestos. Series of tests were carried out on rice husk roofing sheet while the results of tests carried out ...

  4. EFFECT OF SOIL AMENDMENT WITH RICE HUSKS AND COW ...

    African Journals Online (AJOL)

    Pythium damping-off was less severe in the seedlings raised under rice husk and cow dung amendments. Increase in days of decomposition before planting also influenced significantly the effect of rice husk and cow compost on the incidence and severity of the the disease. The number of developed leaves of melon ...

  5. Preparation of High Grade Silica from Rice Husk for Zeolite ...

    African Journals Online (AJOL)

    ABSTRACT: Silica powder with approximately 96% purity was extracted from rice husk (RH) and used as a silica source for the synthesis of zeolite Y ... produced commercially, the ones produced from plant origins such as rice husks have ... About 1.7g sodium hydroxide pellets were dissolved in. 7.5ml deionized water and ...

  6. Assessment of Fibre Characteristics and Suitability of Maize Husk ...

    African Journals Online (AJOL)

    Maize husk and stalk were assessed for their fibre characteristics and suitability for pulp and paper production. Fifteen (15) fibres were randomly selected and measured from each representative sample. It was observed that fibre length of maize husk was 1.37mm and that of maize stalk was 1.52mm. The fibre diameter (D) ...

  7. Ispaghula Husk-Based Extended Release Tablets of Diclofenac ...

    African Journals Online (AJOL)

    Purpose: To formulate extended-release tablets of diclofenac sodium based on ispaghula husk. Methods: Tablets with varying proportions of diclofenac sodium and ispaghula husk were formulated by wet granulation technique at a fixed compression force of 10 kN. The formulated tablets were evaluated for ...

  8. Strength Properties of Processed Fly Ash Concrete

    Directory of Open Access Journals (Sweden)

    Sivakumar Anandan

    2015-07-01

    Full Text Available The present paper reports on the mechanical treatment of fly ash for improving the delayed reactivity of fly ash with the hydration product of cement. Grinding of fly ash was carried out in a ball mill for different time durations and processing time was optimized for maximum fineness. Concrete mixes were prepared using various proportions of processed and unprocessed fly ash replacement in cement (25% and 50%. The influence of steel fiber addition on the mechanical properties of the concrete was studied for different curing periods. The test results on pozzolanic activity and lime reactivity indicate that the processed fly ash exhibited a higher strength gain than the unprocessed fly ash, with a maximum increase in compressive strength of up to 12%. Improved pozzolanic properties were noticed due to the increase in fineness of the fly ash particles.

  9. A Preliminary Study of Pelletized Ecuadorian Cocoa Pod Husk for its Use as a Source of Renewable Energy

    Directory of Open Access Journals (Sweden)

    Luis Velázquez-Araque

    2016-06-01

    Full Text Available In Ecuador, there is a constant need to pursuit energy independence, have created a new industry focused on energy generation by harnessing renewable sources. Biomass is established as the third leading source for producing electricity as the main source for the generation of thermal energy. However, the problems related to the low density of the different types of biomass and the difficulty in carrying and storing have caused the need to generate solids with higher density and stronger hardness known as pellets and briquettes. This paper develops an analysis of the possibilities of pelletizing the Ecuadorian cocoa pod husk and its use as biofuel. Several pellets configurations were proposed based on the diameter and length ratio. An experimental setup was established to crush and screen the cocoa pod husk in order to obtain less than 1.5 mm particle size. Then the pellets were made using a small scale pellet machine and finally burned in a combustion chamber for the evaluation of the energy potential by means of the high heat value and ash content. Finally, the selection of the most energy efficient pellet configuration is made taking into consideration international pellet quality standards as well. This largescale project would represent a cost savings in the Ecuadorian industrial sector leading further to lowering smog emissions into the environment from burning fossil fuels and also it would prevent the cocoa pod husk as a focus for the spread of Phytophthora species which is a main cause of economic losses in the cocoa industry.

  10. rice husk as filler rice husk as filler in the production of bricks using ...

    African Journals Online (AJOL)

    eobe

    on lateritic soils for the manufacturing of fired bricks. Laterite clays were also used to produce rope fiber- reinforced earth blocks and plain fired bricks; the compressive strength of fiber .... machine, and the rice husk was mixed with the clay by weight at 0, 2, 4, 6, 8 and 10%, see Table2. The samples were now taken to a flat ...

  11. Geotechnical engineering properties of incinerator ash mixes.

    Science.gov (United States)

    Muhunthan, B; Taha, R; Said, J

    2004-08-01

    The incineration of solid waste produces large quantities of bottom and fly ash. Landfilling has been the primary mode of disposal of these waste materials. Shortage in landfill space and the high cost of treatment have, however, prompted the search for alternative uses of these waste materials. This study presents an experimental program that was conducted to determine the engineering properties of incinerator ash mixes for use as construction materials. Incinerator ash mixes were tested as received and around optimum compacted conditions. Compaction curves, shear strength, and permeability values of fly ash, bottom ash, and their various blends were investigated. Bottom ash tends to achieve maximum dry density at much lower water content than does fly ash. The mixes displayed a change in their cohesion and friction angle values when one of the two mix components was altered or as a result of the addition of water. The permeability of bottom ash is quite comparable to that of sand. The permeability of fly ash lies in the range of those values obtained for silts and clays. A 100% bottom ash compacted at the optimum water content has a lower density value and yields a higher friction angle and cohesion values than most construction fills. This would encourage the use of bottom ash as a fill or embankment material because free drainage of water will prevent the buildup of pore water pressures.

  12. Influence of functional silanes on hydrophobicity of MCM-41 synthesized from rice husk

    Directory of Open Access Journals (Sweden)

    S. Chiarakorn et al

    2007-01-01

    Full Text Available Mesoporous molecular sieve MCM-41 was synthesized from rice husk and rice husk ash, called RH-MCM-41 and RHA-MCM-41. The sol–gel mixtures were prepared with molar composition of 1.0 SiO2: 1.1 NaOH: 0.13 CTAB: 0.12 H2O. After calcination, the polarity of MCM-41 still remained on its surface due to the existence of some silanol groups. In this study, both RH-MCM-41 and RHA-MCM-41 were silylated with two different functional silanes trimethylchlorosilane (TMCS and phenyldimethylchlorosilane (PDMS in order to reduce the surface polarity. The efficiency of silylation was determined based on the amount of moisture adsorbed using thermogravimetric analysis (TGA. The structure of silylating agents and silica templates were found to be important parameters affecting the hydrophobic property of the MCM-41 surface. The post-grafting silylation with aliphatic silane can decrease the surface polarity better than that with aromatic silane, probably due to less sterric hindrance effect. Thus, the surface hydrophobicity of MCM-41 can be improved by the silylation of small molecular silane on RH-MCM-41.

  13. The Fabrication and Characterization of PCL/Rice Husk Derived Bioactive Glass-Ceramic Composite Scaffolds

    Directory of Open Access Journals (Sweden)

    Farnaz Naghizadeh

    2014-01-01

    Full Text Available The present study was conducted to fabricate a 3D scaffold using polycaprolactone (PCL and silicate based bioactive glass-ceramic (R-SBgC. Different concentrations of R-SBgC prepared from rice husk ash (RHA were combined with PCL to fabricate a composite scaffold using thermally induced phase separation (TIPS method. The products were then characterized using SEM and EDX. The results demonstrated that R-SBgC in PCL matrix produced a bioactive material which has highly porous structure with interconnected porosities. There appears to be a relationship between the increase in R-SBgC concentration and increased material density and compressive modulus; however, increasing R-SBgC concentration result in reduced scaffold porosity. In conclusion, it is possible to fabricate a PCL/bioactive glass-ceramic composite from processed rice husk. Varying the R-SBgC concentrations can control the properties of this material, which is useful in the development of the ideal scaffold intended for use as a bone substitute in nonload bearing sites.

  14. Effect of dietary garlic bulb and husk on the physicochemical properties of chicken meat.

    Science.gov (United States)

    Kim, Y J; Jin, S K; Yang, H S

    2009-02-01

    This study was carried out to compare the physicochemical and sensory properties of chicken thigh muscles from broilers fed different levels of garlic bulb (GB) and garlic husk (GH). Two hundred male Arbor Acre broiler chickens were fed either a control diet (based on corn and soybean meal) or the control diet supplemented with 2 and 4% of GB and GH powder for 5 wk. There were no differences among diets in moisture and ash contents. However, dietary supplementation with GB and GH resulted in significantly greater protein content and lower fat content in chicken thigh muscle compared with muscle from birds fed nonsupplemented diets (Pgarlic supplementation resulted in lower shear force and thiobarbituric acid reactive substances values (Pgarlic led to decreased total and low-density lipoprotein cholesterol levels in broiler blood, and the greatest level of garlic supplementation decreased saturated fatty acid and increased unsaturated fatty acid levels (%) in broiler thigh muscle (Pgarlic dietary supplementation (Pgarlic can produce chicken meat with favorable lipid profiles and can enhance eating quality because sensory panels found that thigh meat from chickens fed a garlic-supplemented diet had better texture and flavor. Therefore, the treatment with the most significant effects in this study was that with the high level of garlic husk.

  15. Characterization of Sodium Carbonate (Na2CO3) Treated Rice Husk Activated Carbon and Adsorption of Lead from Car Battery Wastewater

    Science.gov (United States)

    Hanum, F.; Bani, O.; Izdiharo, A. M.

    2017-03-01

    The use of rice husk as adsorbent would not only reduce its disposal problems, but would also produce value-added products, such as activated carbon derived from rice husk. This study aimed to determine the optimum carbonization temperature for activated carbon production from rice husk and its adsorption performance on Pb in car battery wastewater. In this study, activated carbon was produced by carbonizing rice husk 400-600 °C for 90-150 minutes followed by chemical activation using 5% Na2CO3 and sieving to 100 meshes. Lead adsorption was measured using atomic absorption spectroscopy (AAS). Results suggested that highest carbon yield of 47.75% was obtained for carbonization at 500 °C for 150 minutes. At that condition, produced activated carbon contained 3.35% moisture, 30.86% ash, 18.04% volatile matter. The adsorption capacity was found to be 0.6007 mg lead/g adsorbent with % adsorpsi 58.08%

  16. [Adsorption mechanism of furfural onto modified rice husk charcoals].

    Science.gov (United States)

    Deng, Yong; Wang, Xianhua; Li, Yunchao; Shao, Jing'ai; Yang, Haiping; Chen, Hanping

    2015-10-01

    To evaluate the absorptive characteristics of furfural onto biomass charcoals derived from rice husk pyrolysis, we studied the information of the structure and surface chemistry properties of the rice husk charcoals modified by thermal treatment under nitrogen and carbon dioxide flow and adsorption mechanism of furfural. The modified samples are labeled as RH-N2 and RH-CO2. Fresh rice husk charcoal sample (RH-450) and modified samples were characterized by elemental analysis, nitrogen adsorption-desorption isotherms, Fourier-transform infrared spectroscopy and Boehm titration. The results show that fresh rice husk charcoal obtained at 450 degrees C had a large number of organic groups on its surface and poor pore structure. After the modification under nitrogen and carbon dioxide flow, oxygenic organics in rice husk charcoals decompose further, leading to the reduction of acidic functional groups on charcoals surface, and the increase of the pyrone structures of the basic groups. Meanwhile, pore structure was improved significantly and the surface area was increased, especially for the micropores. This resulted in the increase of π-π dispersion between the surfaces of rice husk charcoals and furfural molecular. With making comprehensive consideration of π-π dispersion and pore structure, the best removal efficiency of furfural was obtained by rice husk charcoal modified under carbon dioxide flow.

  17. Development of asbestos free brake pads using corn husks

    Directory of Open Access Journals (Sweden)

    Wisdom ASOTAH

    2017-12-01

    Full Text Available The development of asbestos free brake pads using corn husks as alternative filler was studied with a view to replacing asbestos, which has been known to be carcinogenic. Corn husks was sourced and milled, before been sieved into sieve grades of 100 and 200 μm. The varying proportions of the as-screened corn husk fibres and silicon carbide were mixed with fixed proportions of graphite, steel dust and resin to produce brake pads by using compressional moulding. The hardness, compressive strength, density, flame resistance, wear rate and porosity of the products were then determined. The result obtained showed that the brake pad produced with the corn husk passing the finer 100 μm screen gave better compressive strength, higher hardness, lower porosity and lower rate of wear, consequent on the finer distribution of the corn husks particles in the matrix. The results obtained for the brake pads were then compared with that of commercial brake pad (asbestos based and optimum formulation laboratory brake pad, corn husk based. The results were found to be in close agreement suggesting that corn husk can be used in the production of asbestos-free brake pads.

  18. Feasibility analysis of the use of sugar cane bagasse ash as mineral addition to cementitious mortars; Analise da viabilidade de utilizacao da cinza do bagaco de cana-de-acucar como adicao mineral em argamassas cimenticias

    Energy Technology Data Exchange (ETDEWEB)

    Fazzan, J.V.; Pereira, A.M.; Moraes, M.J.B. de; Akasaki, J.L.; Sanches, A.O.; Malmonge, J. A., E-mail: jvfazzan@hotmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Ilha Solteira, SP (Brazil). Faculdade de Engenharia. Departamento de Fisica e Quimica

    2014-07-01

    Currently, Brazil is experiencing an expansion of sugarcane plantations, which makes the country the world's largest producer of sugarcane. With the bagasse generated during the process, is generated the bagasse ash cane sugar (CBC) which consists mainly of silicon dioxide (SiO{sub 2}) and presents as potential alternative raw material for the production of cement composites. In this context, the objective of this study is to evaluate the reactivity of the CBC through physical and chemical analysis, for the production of mortars. The study of the CBC was performed by means of XRF testing, XRD, SEM and ADL. Mortar specimens with different percentages of CBC in partial replacement of Portland cement, for analysis of compressive strength were also produced. Despite the mixtures with additions have lower resistance to conventional mortars, the results showed the potential of the CBC as reactive mineral addition. (author)

  19. Functional Analysis of Corn Husk Photosynthesis[W][OA

    Science.gov (United States)

    Pengelly, Jasper J.L.; Kwasny, Scott; Bala, Soumi; Evans, John R.; Voznesenskaya, Elena V.; Koteyeva, Nuria K.; Edwards, Gerald E.; Furbank, Robert T.; von Caemmerer, Susanne

    2011-01-01

    The husk surrounding the ear of corn/maize (Zea mays) has widely spaced veins with a number of interveinal mesophyll (M) cells and has been described as operating a partial C3 photosynthetic pathway, in contrast to its leaves, which use the C4 photosynthetic pathway. Here, we characterized photosynthesis in maize husk and leaf by measuring combined gas exchange and carbon isotope discrimination, the oxygen dependence of the CO2 compensation point, and photosynthetic enzyme activity and localization together with anatomy. The CO2 assimilation rate in the husk was less than that in the leaves and did not saturate at high CO2, indicating CO2 diffusion limitations. However, maximal photosynthetic rates were similar between the leaf and husk when expressed on a chlorophyll basis. The CO2 compensation points of the husk were high compared with the leaf but did not vary with oxygen concentration. This and the low carbon isotope discrimination measured concurrently with gas exchange in the husk and leaf suggested C4-like photosynthesis in the husk. However, both Rubisco activity and the ratio of phosphoenolpyruvate carboxylase to Rubisco activity were reduced in the husk. Immunolocalization studies showed that phosphoenolpyruvate carboxylase is specifically localized in the layer of M cells surrounding the bundle sheath cells, while Rubisco and glycine decarboxylase were enriched in bundle sheath cells but also present in M cells. We conclude that maize husk operates C4 photosynthesis dispersed around the widely spaced veins (analogous to leaves) in a diffusion-limited manner due to low M surface area exposed to intercellular air space, with the functional role of Rubisco and glycine decarboxylase in distant M yet to be explained. PMID:21511990

  20. Process for production of high density/high performance binderless boards from whole coconut husk: Part 2: Coconut husk morphology, composition and properties

    NARCIS (Netherlands)

    Dam, van J.E.G.; Oever, van den M.J.A.; Keijsers, E.R.P.; Putten, van der J.C.; Anayron, C.; Josol, F.; Peralta, A.

    2006-01-01

    For production of compression moulded boards from whole coconut husk the auto-adhesive properties are derived from the intrinsic high lignin content. Since the properties of manufactured boards for a large part will depend on the input husk material these properties are studied here. Husks of

  1. Development of briquette fuel from cashew shells and rice husk mixture

    Science.gov (United States)

    Yohana, Eflita; Arijanto, Kalyana, Ivan Edgar; Lazuardi, Andy

    2017-01-01

    In Indonesia, a large amount of biomasses are available from cashew plantations and rice fields and constitute one of the raw material sources for thermal energy. Annually, 130.052 tons of whole cashews can produce cashew shells with a total energy content of 4,933x109 kcal. In addition, 49 million tons of rice is produced annually in Indonesia. From this sum, 7.5-10 million tons of rice husks are obtained with a total energy content of 2.64x1013 kcal. The purpose of this research is to review the briquette of biomass made from a mixture of cashew shells and rice husks with polyvinyl acetate (PVA) as the adhesive. The mixture ratio of cashew shells and rice husks is varied with a range of 75:25, 50:50, and 25:75 % weight. Briquettes are made in a cylinder mold and pressed using a hydraulic press machine. The pressing pressure varies from 2.500, 5.000, and 7.500 kg/m2. Results show that a briquette with a mixture ratio of 75:25 % shows good pressure tenacity. A model is used to relate density with briquetting pressure. This model shows that the briquette has low compressibility at 0.13. Enhancement of the heating value for the briquettes is also carried out using the torrefaction treatment. The torrefaction process produces biomass briquettes made from a mixture of cashew shells and rice husks with a heating value on par to sub-bituminous coal according to the ASTM D 388 standard classification with a heating value of 6.712 kcal/kg.

  2. Production, Refining, Structural Characterization and Fermentability of Rice Husk Xylooligosaccharides

    NARCIS (Netherlands)

    Gullon, P.; Gonzales-Munoz, M.J.; Gool, van M.P.; Schols, H.A.; Hirsch, J.; Ebringerova, A.; Rarajo, J.C.

    2010-01-01

    Oligosaccharides produced by hydrothermal processing of rice husks (xylooligosaccharides and glucooligosaccharides) were refined by membrane processing (operating in diafiltration and concentration modes), subjected to xylanase treatment to reduce the average molar mass, and subjected to further

  3. Possibilities of utilizing power plant fly ashes

    Directory of Open Access Journals (Sweden)

    Mezencevová Andrea

    2003-09-01

    Full Text Available The burning of fossil fuels in industrial power stations plays a significant role in the production of thermal and electrical energy. Modern thermal power plants are producing large amounts of solid waste, mainly fly ashes. The disposal of power plant waste is a large environmental problem at the present time. In this paper, possibilities of utilization of power plant fly ashes in industry, especially in civil engineering, are presented. The fly ash is a heterogeneous material with various physical, chemical and mineralogical properties, depending on the mineralogical composition of burned coal and on the used combustion technology. The utilization of fly ashes is determined of their properties. The fineness, specific surface area, particle shape, density, hardness, freeze-thaw resistance, etc. are decisive. The building trade is a branch of industry, which employs fly ash in large quantities for several decades.The best utilization of fluid fly ashes is mainly in the production of cement and concrete, due to the excellent pozzolanic and cementitious properties of this waste. In the concrete processing, the fly ash is utilized as a replacement of the fine aggregate (fine filler or a partial replacement for cement (active admixture. In addition to economic and ecological benefits, the use of fly ash in concrete improves its workability and durability, increases compressive and flexural strength, reduces segregation, bleeding, shrinkage, heat evolution and permeability and enhances sulfate resistance of concrete.The aim of current research is to search for new technologies for the fly ash utilization. The very interesting are biotechnological methods to recovery useful components of fly ashes and unconventional methods of modification of fly ash properties such as hydrothermal zeolitization and mechanochemical modification of its properties. Mechanochemistry deals with physico - chemical transformations and chemical reactions of solids induced by

  4. Structural and Mechanical Characterization of Sustainable Composites Based on Recycled and Stabilized Fly Ash

    Directory of Open Access Journals (Sweden)

    Stefano Besco

    2014-08-01

    Full Text Available This paper reports the results on the use of an innovative inert, based on stabilized fly ash from municipal solid waste incineration as a filler for polypropylene. The starting material, which contains large quantities of leachable Pb and Zn, was stabilized by means of an innovative process using rice husk ash as a waste silica source, together with other fly ashes, such as coal fly ash and flue gas desulfurization residues. The use of all waste materials to obtain a new filler makes the proposed technology extremely sustainable and competitive. The new composites, obtained by using the stabilized material as a filler for polypropylene, were characterized and their mechanical properties were also investigated. A comparison with a traditional polypropylene and calcium carbonate based compound was also done. This research activity was realized in the frame of the COSMOS-RICE project, financed by the EU Commission.

  5. Wood-ash addition on a drained forest peatland in Southern Sweden - Effects on water chemistry; Tillfoersel av biobra ensleaska i tallskog paa en dikad torvmark i soedra Sverige - Effekter paa vattenkemin

    Energy Technology Data Exchange (ETDEWEB)

    Ring, Eva; Broemssen, Claudia von; Losjoe, Katarina; Sikstroem Ulf

    2012-02-15

    Wood ash can be used for forest fertilization on peatlands or for nutrient compensation following intensive harvesting. This project was performed in order to investigate effects on water chemistry of applying wood ash to a Scots pine stand on a drained peatland. Ditch-water chemistry was monitored before and after the application of wood ash. Furthermore, groundwater was collected and chemically analyzed both from the ash-treated peatland and from an adjacent untreated reference peatland. Both short term (a few months) and more long term effects (up to three years after application) were detected on water chemistry

  6. MECHANICAL, ELECTRICAL, AND THERMAL PROPERTIES OF MALEIC ANHYDRIDE MODIFIED RICE HUSK FILLED PVC COMPOSITES

    OpenAIRE

    Navin Chand; Bhajan Das Jhod

    2008-01-01

    Unmodified and modified rice husk powder filled PVC composites were prepared having different amounts of rice husk powder. Mechanical, thermal, and electrical properties of these composites were determined. The tensile strength of rice husk powder PVC composites having 0, 10, 20, 30, and 40 weight percent of rice husk powder was found to be 33.9, 19.4, 18.1, 14.6, and 9.5 MPa, respectively. Adding of maleic anhydride- modified rice husk powder improved the tensile strength of rice husk powder...

  7. Sorghum husk biomass as a potential substrate for production of cellulolytic and xylanolytic enzymes by Nocardiopsis sp. KNU.

    Science.gov (United States)

    Kshirsagar, Siddheshwar D; Bhalkar, Bhumika N; Waghmare, Pankajkumar R; Saratale, Ganesh D; Saratale, Rijuta G; Govindwar, Sanjay P

    2017-07-01

    Nocardiopsis sp. KNU was found to degrade various lignocellulosic waste materials, namely, sorghum husk, sugarcane tops and leaves, wheat straw, and rice husk very efficiently. The strain was found to produce high amounts of cellulase and hemicellulase. Augmentation of cotton seed cake as an organic nitrogen source revealed inductions in activities of endoglucanase, glucoamylase, and xylanase up to 70.03, 447.89, and 275.10 U/ml, respectively. Nonionic surfactant Tween-80 addition was found to enhance the activity of endoglucanase enzyme. Cellulase produced by Nocardiopsis sp. KNU utilizing sorghum husk as a substrate was found to retain its stability in various surfactants up to 90%. The produced enzyme was further tested for saccharification of mild alkali pretreated rice husk. The changes in morphology and functional group were analyzed using scanning electron microscopy and Fourier transform infrared spectroscopy. Enzymatic saccharification confirmed the hydrolytic potential of crude cellulase. The hydrolysate products were analyzed by high-performance thin layer chromatography.

  8. Effects of soluble fiber (Plantago ovata husk) on plasma lipids, lipoproteins, and apolipoproteins in men with ischemic heart disease.

    Science.gov (United States)

    Solà, Rosa; Godàs, Gemma; Ribalta, Josep; Vallvé, Joan-Carles; Girona, Josefa; Anguera, Anna; Ostos, Maadoracion; Recalde, Delia; Salazar, Juliana; Caslake, Muriel; Martín-Luján, Francisco; Salas-Salvadó, Jordi; Masana, Lluís

    2007-04-01

    New dietary strategies to reduce cardiovascular disease (CVD) risk include the addition of fiber to the diet. The effect of soluble-fiber consumption derived from Plantago ovata husk on lipid risk factors in patients with CVD is unknown. We compared the effects of soluble fiber (P. ovata husk) with those of insoluble fiber (P. ovata seeds) on plasma lipid, lipoprotein, and apolipoprotein (apo) concentrations within a CVD secondary prevention program. In a randomized, crossover, controlled, single-blind design, 28 men with CVD (myocardial infarction or stable angina) and an LDL-cholesterol concentration fiber, the intake of P. ovata husk increased HDL-cholesterol concentrations by 6.7% (P = 0.006) and decreased the ratio of total to HDL cholesterol and of LDL to HDL cholesterol by 10.6% (P = 0.002) and 14.2% (P = 0.003), respectively. In the secondary prevention of CVD, P. ovata husk intake induces a more beneficial effect on the cardiovascular lipid risk-factor profile than does an equivalent intake of insoluble fiber.

  9. Can vegetative ash be water repellent?

    Science.gov (United States)

    Bodí, M. B.; Cerdà, A.; Mataix-Solera, J.; Doerr, S. H.

    2012-04-01

    In most of the literature, ash is referred to as a highly wettable material (e.g. Cerdà and Doerr, 2008; Etiegni and Campbell, 1991; Woods and Balfour 2010). However, the contrary was suggested in few articles, albeit with no further quantification (Gabet and Sternberg, 2008; Khanna et al., 1996; Stark, 1977). To clarify this question, water repellency measurements on ash using the Water Drop Penetration Times (WDPT) method were performed on ash from Mediterranean ecosystems and it was found to be water repellent (Bodí et al. 2011). Water repellency on ash from different wildfires ranged from 40 to 10 % occurrence with samples being extreme repellent (lasting more than 3600 s to penetrate). Part of the ash produced in the laboratory was also water repellent. After that, other ash samples had been found water repellent in wildfires in Colorado (unpublished results), Portugal (Gonzalez-Pelayo, 2009), or in prescribed fires in Australia (Bodí et al. 2011b; Petter Nyman, personnal communication). All the samples exhibiting water repellent properties had in common that were combusted at low temperatures, yielding in general ash with dark colour and contents of organic carbon of more than 18 % (Bodí et al. 2011a), although these properties were not exactly proportional to its water repellency occurrence or persistence. In addition, the species studied in Bodí et al. (2011) had been found to produce different levels of WR repellency, being ash from Pinus halepensis more repellent than that from Quercus coccifera and Rosmarins officinalis. Ash from Eucaliptus radiata had been found also very water repellent, as Pinus halepensis (unpublished data). The reasons of the existance of water repellent ash are that the charred residue produced by fire (an also contained in the ash) can contain aromatic compounds that have a lower free energy than water and therefore behave as hydrophobic materials with reduced solubility (Almendros et al., 1992 and Knicker, 2007

  10. CZECH FLUID SULFOCALCIC ASH AND FLY ASH

    Directory of Open Access Journals (Sweden)

    Frantisek Skvara

    2016-10-01

    Full Text Available Sulfocalcic ash is formed during the fluidized bed combustion of coal in the presence of limestone. It differs from classical fly ash by its composition and properties. Sulfocalcic ash contains free CaO, CaSO₄ and partially sintered aluminosilicates. In contact with water, it produces Ca(OH₂, expansive ettringite and a small amount of the CSH phase. There is little information about these ashes in the literature. At present, the possibility of using fluid sulfocalcic ashes is quite limited because of the formation of expansive ettringite. More research in the field of sulfocalcic ashes is a necessity because increasing quantities of this product are rejected by the energy-generation industry.

  11. STABILIZATION OF EXPANSIVE SOIL USING BAGASSE ASH & LIME

    African Journals Online (AJOL)

    tekimerry

    (MDD) and plasticity of the soil for all additives. But there was also a tremendous improvement in the CBR value when the soil is stabilized with a combination of lime and bagasse ash. This shows a potential of using bagasse ash as admixture in lime stabilized expansive soil. Keywords: Expansive soil, bagasse ash, lime,.

  12. Ashes from fluidized bed combustion of residual forest biomass

    NARCIS (Netherlands)

    Cruz, Nuno C.; Rodrigues, Sónia M.; Carvalho, Lina; Duarte, Armando C.; Pereira, Eduarda; Romkens, Paul; Tarelho, Luís A.C.

    2017-01-01

    Although bottom ash (BA) [or mixtures of bottom and fly ash (FA)] from clean biomass fuels is currently used as liming agent, additive for compost, and fertilizer on agricultural and forest soils in certain European countries, in several other countries most of the ashes are currently disposed in

  13. [Ash Meadows Purchase Proposal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A proposal sent to the Richard King Mellon Foundation for a loan to fund the purchase of Ash Meadows by the Nature Conservancy. Ash Meadows, set outside of Las Vegas...

  14. A cost–effective and eco-friendly treatment technology to remove realistic levels of mercury by means of the unmodified rice husk

    Directory of Open Access Journals (Sweden)

    Rocha L. S.

    2013-04-01

    Full Text Available In the present work the removal of mercury from aqueous solutions media and for realistic concentrations of this metal was evaluated, by using an inexpensive and highly available agricultural waste, rice husk. An economical method was developed based on the use of the natural/unmodified form of rice husk and on the amount of material required, which was minimized to produce the lowest amount of biological slurry. In order to study the kinetics of the process, batch stirred experiments were performed for initial concentrations of Hg2+ of: 50 μg L–1, representing the actual maximum value for Hg discharges from industrial sectors, and 500 μg L–1, to simulate a situation of an accidental spill. The kinetic curves were described by a rapid removal of Hg2+ by rice husk, in the first hours of contact, followed by a slower removal of Hg2+, until it reaches equilibrium. The removal of Hg2+ using a rice husk dose of 0.50 g L–1 was ca. 83% for an initial concentration of 50 μg L–1 and 92% for 500 μg L–1. Furthermore, the results show that is possible the reuse the rice husk in additional cleaning treatments, maintaining the efficiency of the removal process.

  15. Market assessment and technical feasibility study of PFBC ash use

    Energy Technology Data Exchange (ETDEWEB)

    Smith, V.E.; Bland, A.E.; Brown, T.H. [Western Research Inst., Laramie, WY (United States); Georgiou, D.N. [Jacques, Whitford and Associates Ltd., Dartmouth, NS (Canada); Wheeldon, J. [Electric Power Research Inst., Palo Alto, CA (United States)

    1994-10-01

    The overall objectives of this study are to determine the market potential and the technical feasibility of using PFBC ash in high volume ash use applications. The information will be of direct use to the utility industry in assessing the economics of PFBC power generation in light of ash disposal avoidance through ash marketing. In addition, the research is expected to result in the generation of generic data on the use of PFBC ash that could lead to novel processing options and procedures. The specific objectives of the proposed research and demonstration effort are: Define resent and future market potential of PFBC ash for a range of applications (Phase I); assess the technical feasibility of PFBC ash use in construction, civil engineering and agricultural applications (Phase II); and demonstrate the most promising of the market and ash use options in full-scale field demonstrations (Phase III).

  16. Utilization of blended fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash in geopolymer.

    Science.gov (United States)

    Chindaprasirt, Prinya; Rattanasak, Ubolluk

    2010-04-01

    In this paper, synthesis of geopolymer from fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash was studied in order to effectively utilize both ashes. FBC-fly ash and bottom ash were inter-ground to three different finenesses. The ashes were mixed with as-received PCC-fly ash in various proportions and used as source material for synthesis of geopolymer. Sodium silicate (Na(2)SiO(3)) and 10M sodium hydroxide (NaOH) solutions at mass ratio of Na(2)SiO(3)/NaOH of 1.5 and curing temperature of 65 degrees C for 48h were used for making geopolymer. X-ray diffraction (XRD), scanning electron microscopy (SEM), degree of reaction, and thermal gravimetric analysis (TGA) were performed on the geopolymer pastes. Compressive strength was also tested on geopolymer mortars. The results show that high strength geopolymer mortars of 35.0-44.0MPa can be produced using mixture of ground FBC ash and as-received PCC-fly ash. Fine FBC ash is more reactive and results in higher degree of reaction and higher strength geopolymer as compared to the use of coarser FBC ash. Grinding increases reactivity of ash by means of increasing surface area and the amount of reactive phase of the ash. In addition, the packing effect due to fine particles also contributed to increase in strength of geopolymers. Copyright 2009 Elsevier Ltd. All rights reserved.

  17. Computational fluid dynamics modeling of rice husk combustion

    Science.gov (United States)

    Le, Kien Anh

    2017-09-01

    The combustion of rice husk fuel in a fixed bed reactor can be assumed very complicated. Researchers have studied this problem for many years. Such studies have been performed by both empirical and computational methods. However, due to the sharp increase in the development of computer science based packages, the Computational Fluid Dynamics (CFD) technique can be applied to simulate and analyse the performance of the combustion reaction. Consequently, this has saved on empirical expenditures and has additionally provided more understanding about the research objective. This paper models the computation of bed fuel combustion in a fixed bed reactor using Fluent version 12.0.16. The User Defined Functions (UDFs) were created to define the system as well as boundary conditions, and initial conditions. Furthermore, the source terms, heat exchanges and homogeneous reactions were also defined in UDFs. The species transport and volume reaction were used to model the gas phase, where the Eulerian model was employed to solve the problem using two phase modelling. The k-ɛsub-model was employed for turbulence, together with an unsteady model, as the problem was regarded as being unstable. The results obtained from the modelling work would give more understanding about the bed fuel combustion in fixed bed reactor.

  18. Removal of Zn(II) and Pb (II) ions Using Rice Husk in Food Industrial ...

    African Journals Online (AJOL)

    The adsorption behavior of Zn2+ and Pb2+ ions on rice husk was investigated using Rice Husk to remove the metals ions in dairy wastewater. The removal of mentioned heavy metal ions from aqueous solutions was studied by batch method. The main parameters that influencing Zn 2+ and Pb2+ sorption on rice husk were: ...

  19. Application of chitosan padded rice and wheat husk for the removal ...

    African Journals Online (AJOL)

    Chitosan itself act as a good adsorbent and its derivative with rice and wheat husk (mainly cellulose) show high removal tendency and may be used as low cost biosorbents for the removal of pollutants from the industrial effluent. Keywords: Adsorption, reactive red 195 dye, chitosan, rice husk, wheat husk ...

  20. Geotechnical characterization of some Indian fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Das, S.K.; Yudhbir [Indian Institute for Technology, Kanpur (India). Dept. of Civil Engineering

    2005-10-01

    This paper reports the findings of experimental studies with regard to some common engineering properties (e.g., grain size, specific gravity, compaction characteristics, and unconfined compression strength) of both low and high calcium fly ashes, to evaluate their suitability as embankment materials and reclamation fills. In addition, morphology, chemistry, and mineralogy of fly ashes are studied using scanning electron microscope, electron dispersive x-ray analyzer, x-ray diffractometer, and infrared absorption spectroscopy. In high calcium fly ash, mineralogical and chemical differences are observed for particles, {gt}75 {mu} m and the particles of {lt} 45 {mu} m size. The mode and duration of curing significantly affect the strength and stress-strain behavior of fly ashes. The geotechnical properties of fly ash are governed by factors like lime content (CaO), iron content (Fe{sub 2}O{sub 3}) and loss on ignition. The distinct difference between self-hardening and pozzolanic reactivity has been emphasized.

  1. Potential of rice husks for antimony removal.

    Science.gov (United States)

    Khalid, N; Ahmad, S; Toheed, A; Ahmed, J

    2000-01-01

    The adsorption behavior of rice husks for antimony ions from aqueous solutions has been investigated as a function of appropriate electrolyte, equilibration time, hydrogen ions, amount of adsorbent, concentration of adsorbate, effect of diverse ions and temperature. The best conditions in which this material can be used as adsorbent have been explored. The radiotracer technique was employed to determine the distribution of antimony (122Sb) using a batch method. Maximum adsorption was observed at 0.01 mol L(-1) acid solutions (HNO3, HCl, H2SO4 and HClO4) using 1.0 g of adsorbent for 1.92 x 10(-5) mol L(-1) antimony concentration in 10 min equilibration time. Studies show that the adsorption decreases with the increase in the concentrations of all the acids. The adsorption data follow the Freundlich isotherm over the range of 1.92 x 10(-5) to 2.05 x 10(-4) mol L(-1) antimony concentration. The characteristic Freundlich constants i.e., 1/n = 0.82 +/- 0.05 and K = 4.61 +/- 0.07 m mol g(-1) have been computed for the sorption system. The uptake of antimony increases with the rise in temperature (299-323 K). Thermodynamic quantities i.e., deltaG0, deltaS0 and deltaH0 have also been calculated for the system. The sorption process was found to be endothermic.

  2. Effect of cocoa pod husk filler loading on tensile properties of cocoa pod husk/polylactic acid green biocomposite films

    Science.gov (United States)

    Sanyang, M. L.; Sapuan, S. M.; Haron, M.

    2017-10-01

    Over the years, cocoa-pod husk (CPH) generation significantly increased due to the growing global demand of chocolate products, since cocoa bean is the main ingredient for chocolate production. Proper utilization of CPH as natural filler for reinforcement of polymer composites provides economic advantages as well as environmental solutions for CPH waste disposal problems. In this study, CPH filled PLA composite films were developed using solution casting method. The effect of CPH loading on the tensile properties of CPH/PLA composite films were investigated. The obtained results manifested that increasing CPH loading from 0% to 10 % significantly increased tensile strength of CPH/PLA composite. However, further addition of CPH loading up to 15 % decreased the tensile strength of film samples. As CPH loading increased from 0% to 15%, tensile modulus of CPH/PLA composite films also increased from 1.5MPa to 10.4MPa, whereas their elongation at break reduced from 190% to 90%. These findings points out CPH as a potential natural filler for reinforcing thermoplastic polymer composites.

  3. Removal of iron from groundwater by ash: a systematic study of a traditional method.

    Science.gov (United States)

    Das, B; Hazarika, P; Saikia, G; Kalita, H; Goswami, D C; Das, H B; Dube, S N; Dutta, R K

    2007-03-22

    A traditional method for removal of iron from ground water by using ash has been systematically investigated. Ashes from five different sources, viz., banana rind, banana pseudostem, banana leaf, rice husk and bamboo has been studied. The principle applied is enhanced precipitation of iron at high pH caused by ash. The study included laboratory analysis of some relevant chemical parameters of the ashes and the efficiency of the ashes in removing iron from prefabricated water with respect to quantity of ash and corresponding increase in pH of water. The ash of banana pseudostem has been found to be most suitable for removal of iron. A low-cost and easily made iron removal system for household use has been designed and tested in the laboratory. The ash of banana pseudostem has been found to remove iron to below 0.3ppm without increasing the pH above the acceptable limit. The optimum values of the different parameters for removal of iron are 200-300mgl(-1) ash, 1.0lh(-1) flow rate and 1h of contact time with ash for groundwater having [Fe] of about 2.20ppm. The amount of ash can be increased for groundwater having higher [Fe] and can be decreased gradually during continuous use of the system. Acceptability of the method has been examined based on chemical analysis of the treated water. Increase in the essential minerals such as Ca, K has been observed in the water after treatment. The designed iron removing system is expected to be suitable for household use.

  4. Characteristics of a β-1,4-D endoglucanase from Trichoderma virens wholly applied in a palm-fruit husk-based diet for poultry layers.

    Science.gov (United States)

    Odeniyi, Olubusola A; Onilude, Anthony A; Ayodele, Maria A

    2012-10-01

    The characteristics of an endoglucanase produced by a Trichoderma virens strain T9 newly isolated from a palm-fruit husk dump site, its physiological characteristics and enzyme production were studied. Whole cells of the depolymerizing-enzyme producing T. virens were applied to palm-fruit husk and bird performance characteristics when employed as poultry diet additive were considered. Endoglucanase activity in submerged fermentation was 1.6 nkat. Optimum activity was recorded at pH 6.0 and 55°C. The enzyme retained 50% residual glucanase activity at 70°C for 10 minutes. 1.0% Tween-80 and SDS yielded endoglucanase activity 2.15 times higher than the control. Activity was boosted by 20mM Ca(2+) (115.0%); 10mM K(+) (106.5%); and was totally inhibited by 1mM Hg(2+). The addition of T. virens-fermented palm-fruit husk with other layer feed components on the bird characteristics showed that change in bird weight between the control and test birds were not significantly different (p>0.05) but differed in terms of daily feed ingested (phusk based diet (8.59). There was no significant difference in the egg weights from modified palm-fruit husk based diet and control (p>0.05). The shell thickness (0.64mm) and yolk content (23.61%) were highest in the microbially-modified husk diet. The alternative to maize based diets proffered by the application of T. virens-modified palm-fruit husk in poultry nutrition in terms of bird weight and feed to weight-gain ratio affords the poultry farmer an economic advantage and allows for a greater utilization of the maize in human diets.

  5. Decomposition of wheat bran and ispaghula husk in the stomach and the small intestine of healthy men

    DEFF Research Database (Denmark)

    Andersen, J R; Bukhave, K; Højgaard, L

    1988-01-01

    Decomposition of dietary fibers in the stomach and small bowel was studied in 13 healthy male volunteers. Liquid control meals were compared with test meals, which in addition contained a source of fiber (wheat bran or ispaghula husk) in random order. Aspirations were collected from the stomach...... for monosaccharides, either free or fiber-bound, by gas-liquid chromatography. Both types of fiber were hydrolyzed in the stomach, but not in the small bowel. Of ispaghula husk, 1-6% was hydrolyzed, as was 5-8% of wheat bran. Intestinal absorption of free arabinose was 85-93%, but excretion of arabinose in the urine...... was not greater than after control meals. For further evaluation of gastric hydrolysis six additional healthy male volunteers were studied by serial aspirations from the antral part of the stomach. Hydrolysis was instantaneous for both fibers, and was significantly more pronounced for wheat bran than...

  6. Comparative study of various pretreatment reagents on rice husk and structural changes assessment of the optimized pretreated rice husk.

    Science.gov (United States)

    Ang, Teck Nam; Ngoh, Gek Cheng; Chua, Adeline Seak May

    2013-05-01

    The performance of alkalis (NaOH and Ca(OH)2) and acids (H2SO4, HCl, H3PO4, CH3COOH, and HNO3) in the pretreatment of rice husk was screened, and a suitable reagent was assessed for subsequent optimization using response surface methodology. From the assessment, HCl that hydrolysed rice husk well was optimized with three parameters (HCl loading, pretreatment duration, and temperature) using Box-Behnken Design. The optimized condition (0.5% (w/v) HCl loading, 125 °C, 1.5 h) is relatively mild, and resulted in ~22.3mg TRS/ml hydrolysate. The reduced model developed has good predictability, where the predicted and experimental results differ by only 2%. The comprehensive structural characterization studies that involved FT-IR, XRD, SEM, and BET surface area determination showed that the pretreated rice husk consisted mainly of cellulose and lignin. Compared to untreated rice husk, pretreated rice husk possessed increased pore size and pore volume, which are expected to be beneficial for fungal growth during fermentation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Electrical properties of Al-, Cu-, Zn- rice husk charcoal junctions

    Science.gov (United States)

    Dahonog, L. A.; Tapia, A. K. G.

    2017-04-01

    Rice husk in the Philippines is considered as an agricultural waste. In order to utilize the material, one common technique is to carbonize these rice husks to produce charcoal briquettes. These materials are porous in nature exhibiting electrical properties from carbon structures. In this study, rice husk charcoals (RHC) were deposited on different metal substrates (Al, Cu, Zn) via a simple solution casting method. The deposited RHC on metal substrates was observed using Scanning Electron Microscopy (SEM). The films were characterized using two-point probe technique and the I-V curves were plotted. Al-RHC films appear to deviate from an ohmic behaviour while Zn-RHC and Cu-RHC showed diode-like behaviours.

  8. RICE HUSK SILICA-COATED MAGNETIC PARTICLES AS A LOW COST SUPPORT MATERIAL FOR CRUDE Pseudomonas aeruginosa LIPASE IMMOBILIZATION

    Directory of Open Access Journals (Sweden)

    Noor Hindryawati

    2016-11-01

    Full Text Available In this research, lipase produced from the bacteria Pseudomonas aeruginosa was immobilized on rice husk silica-coated Fe3O4 nanoparticles. The process included the following steps: preparation of magnetic ferosoferic oxide nanoparticles (NP, coating NP with silica from rice husk ash, activation with glutaraldehyde and covalent immobilization of lipase on the support. The synthesis of the nanoparticle was followed by characterization through FT-IR, XRD, and FE-SEM. The hydrolysis kinetics (using 4-Nitrophenyl palmitate as a substrate of the immobilized lipase followed Michaelis-Menten model with a Vmax and a Km value of 4.0 mM.s-1 and 0.63 mM, respectively. The immobilized lipase showed better tolerance to extreme temperature and pH compared to free lipase. About 60% of enzyme remained immobilized after ten cycles of reuse and 68.13% of it were stable until 49 days. Thus the silica-coated Fe3O4 nanoparticles appeared to be a potential support material for lipase immobilization applications.

  9. Effect of ash circulation in gasification melting system on concentration and leachability of lead in melting furnace fly ash.

    Science.gov (United States)

    Okada, Takashi; Suzuki, Masaru

    2013-11-30

    In some gasification-melting plants, generated melting furnace fly ash is returned back to the melting furnace for converting the ash to slag. This study investigated the effect of such ash circulation in the gasification-melting system on the concentration and leachability of lead in the melting furnace fly ash. The ash circulation in the melting process was simulated by a thermodynamic calculation, and an elemental analysis and leaching tests were performed on a melting furnace fly ash sample collected from the gasification-melting plant with the ash circulation. It was found that by the ash circulation in the gasification-melting, lead was highly concentrated in the melting furnace fly ash to the level equal to the fly ash from the ash-melting process. The thermodynamic calculation predicted that the lead volatilization by the chlorination is promoted by the ash circulation resulting in the high lead concentration. In addition, the lead extraction from the melting furnace fly ash into a NaOH solution was also enhanced by the ash circulation, and over 90% of lead in the fly ash was extracted in 5 min when using 0.5 mol l(-1) NaOH solution with L/S ratio of 10 at 100 °C. Based on the results, a combination of the gasification-melting with the ash circulation and the NaOH leaching method is proposed for the high efficient lead recovery. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Addition of ash in drained peatland forests in southern Sweden - Forest yield and fluxes of greenhouse gases; Tillfoersel av aska i skog paa dikad torvmark i soedra Sverige - Skogsproduktion och emission av vaexthusgaser

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem Ulf (Skogforsk, Uppsala (Sweden)); Bjoerk, Robert G; Klemedtsson, Leif (Goeteborgs universitet (Sweden))

    2012-02-15

    The objective of the present study was to evaluate effects of wood-ash application (3.3 and 6.6 tonnes d.w. self-harden crushed wood ash ha-1) in forests on drained peatlands in southern Sweden. Tree growth (three sites) and fluxes of greenhouse gases (one site) were measured in field experiments. In the two experiments (Anderstorp and Bredaryd) in Scots pine stands (Pinus sylvestris L.) on oligotrophic mires, tree growth increased significantly during the seven-eight year long effect periods after ash application. In an earlier study in Anderstorp, the annual emissions of CO{sub 2}, CH{sub 4} and N{sub 2}O from the peat were shown to be unaffected by the ash application. In Skogaryd, a Norway spruce stand (Picea abies L. Karst.) on a minerotrophic mire, the growth was indicated to increase during the five-year effect period. In the same experiment, the previously found reduction in emissions of both CO{sub 2} and N{sub 2}O during the first two years after ash application were no longer significant, although the emissions where lower, for N{sub 2}O only in the high dose ash treatment. CH{sub 4} was unaffected during the whole observed period. During the first five years, application of 3-6 tonnes d.w. crushed wood ash ha-1 in the two studied forests on drained peatlands did not render in an increased Global Warming Potential (GWP), but rather a reduction

  11. A Comprehensive Review on the Properties of Coal Bottom Ash in Concrete as Sound Absorption Material

    OpenAIRE

    Ramzi Hannan Nurul Izzati Raihan; Shahidan Shahiron; Ali Noorwirdawati; Maarof Mohamad Zulkhairi

    2017-01-01

    The government is currently implementing policies to increase the usage of coal as fuel for electricity generation. At the same time, the dependency on gas will be reduced. In addition, coal power plants in Malaysia produce large amounts of industrial waste such as bottom ash which is collected in impoundment ponds (ash pond). However, millions of tons of coal ash (bottom ash) waste are collected in ponds near power plant stations. Since bottom ash has been classified as hazardous material th...

  12. Shedding of ash deposits

    DEFF Research Database (Denmark)

    Zbogar, Ana; Frandsen, Flemming; Jensen, Peter Arendt

    2009-01-01

    Ash deposits formed during fuel thermal conversion and located on furnace walls and on convective pass tubes, may seriously inhibit the transfer of heat to the working fluid and hence reduce the overall process efficiency. Combustion of biomass causes formation of large quantities of troublesome...... ash deposits which contain significant concentrations of alkali, and earth-alkali metals. The specific composition of biomass deposits give different characteristics as compared to coal ash deposits, i.e. different physical significance of the deposition mechanisms, lower melting temperatures, etc....... Low melting temperatures make straw ashes especially troublesome, since their stickiness is higher at lower temperatures, compared to coal ashes. Increased stickiness will eventually lead to a higher collection efficiency of incoming ash particles, meaning that the deposit may grow even faster...

  13. Addition of ash and PK with or without N on a peatland in southern Sweden. Effects on tree growth and needle element concentrate; Tillfoersel av aska och PK med eller utan N paa en torvmark i soedra Sverige. Effekter paa traedtillvaext och aemneshalter i barr

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem, Ulf (Forestry Research Inst. of Sweden, Uppsala (Sweden))

    2008-04-15

    In Sweden, about 1.3 million tonnes of ash are produced annually. Out of that amount, 150 000 - 300 000 tonnes have been estimated to originate from forest fuels, i.e. ashes that potentially can be brought back to the forest. Apart from being a compensatory measure after intensive forest harvest (e.g. including tops and branches), the ash may be used to increase the tree growth on peat soils (ash fertilization). On peat soils, tree growth is generally increased after addition of ash or phosphorous (P) and potassium (K) fertilizers. However, in some cases also nitrogen (N) addition is required. On sparsely stocked mires, fertilization may promote the regeneration as well as increase the growth of the trees. Sufficient drainage and supply of plant-available N are some prerequisites for increasing tree growth by PK-addition. In 1982, Skogforsk established a field experiment (168 Perstorp) located in the province of Scania in a sparsely stocked Pinus Sylvestris (L.) sapling stand on a ditched mire where different nutrient regimes were tested. The experiment had a randomized block design including four blocks and seven treatments. Ash and different dozes of P (raw phosphate) and K (potassium chloride), with or without simultaneous N addition, were included as well as un untreated control. The aim of the present study was to evaluate the effects on tree growth and needle elemental concentrations 26 years after treatment. The addition of similar dozes of P (approx. 40 kg P/ha), as ash (2.5 tonnes/ha) or as PK-fertilizer rendered similar growth responses. The increase in stem-wood growth was in the order of 1,6 - 1,9 m3/ha/yr during the 26-year period. The N-addition had no additional effect. On the control plots, the growth was more or less negligible (approx. 0,04 m3sk/ha/yr). On average, the high dozes of raw-phosphate and potassium chloride (40 kg P/ha and 80 kg K/ha) gave a higher growth increase than the low dozes (20 kg P/ha and 40 kg K/ha), although this effect was

  14. Possibilities of municipal solid waste incinerator fly ash utilisation.

    Science.gov (United States)

    Hartmann, Silvie; Koval, Lukáš; Škrobánková, Hana; Matýsek, Dalibor; Winter, Franz; Purgar, Amon

    2015-08-01

    Properties of the waste treatment residual fly ash generated from municipal solid waste incinerator fly ash were investigated in this study. Six different mortar blends with the addition of the municipal solid waste incinerator fly ash were evaluated. The Portland cement replacement levels of the municipal solid waste incinerator fly ash used were 25%, 30% and 50%. Both, raw and washed municipal solid waste incinerator fly ash samples were examined. According to the mineralogical composition measurements, a 22.6% increase in the pozzolanic/hydraulic properties was observed for the washed municipal solid waste incinerator fly ash sample. The maximum replacement level of 25% for the washed municipal solid waste incinerator fly ash in mortar blends was established in order to preserve the compressive strength properties. Moreover, the leaching characteristics of the crushed mortar blend was analysed in order to examine the immobilisation of its hazardous contents. © The Author(s) 2015.

  15. Anti-obesity effects of chitosan and psyllium husk with L-ascorbic acid in guinea pigs.

    Science.gov (United States)

    Jun, Sung Chul; Jung, Eun Young; Hong, Yang Hee; Park, Yooheon; Kang, Duk ho; Chang, Un Jae; Suh, Hyung Joo

    2012-04-01

    The aim of this study was to investigate whether L-Ascorbic acid would facilitate the anti-obesity effects of chitosan and psyllium husk in vivo. The study was carried out with male Hartley guinea pigs for 5 weeks. The results show that chitosan itself did not influence body weight gain and food efficiency ratio (FER). However, the addition of L-Ascorbic acid to chitosan decreased these parameters; the body weight gain and FER in the chitosan-2 group (high-fat diet group with 5 % chitosan containing 0.5 % L-Ascorbic acid) was significantly (p psyllium husk did not differ from psyllium husk alone in terms of changes in weight gain, plasma lipid levels, and fat pad weight. We found that the addition of L-Ascorbic acid to chitosan influenced the reduction in body weight gain and FER, and the increase in total fecal weight and fecal fat excretion in guinea pigs fed a high-fat diet.

  16. Ash tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Hald, P.

    1995-12-01

    This report describes the ash tracer technique which has been developed, used and evaluated for description of the extent of burnout for Cerrejon coal and wheat straw converted in a pressurized entrained-flow reactor. The uncertainty in the calculated extent of burnout depends on the uncertainty in the ash percentages determined for fuel and fuel sample. The uncertainty increases with decreasing amounts of material used for the ash percent determinations, as the natural variation within the fuel and fuel sample becomes obvious. Ash percentages for the original fuels have an absolute deviation within 0.2% with a remaining ash amount of minimum 100 mg and of 2% when using thermogravimetric analysis equipment where 0.4 - 4 mg was remaining. Repeated ash percent determinations by thermogravimetric analysis equipment of 40 samples showed an average absolute deviation of 3%. A temperature of 1000 deg. C is shown to be the best choice for the ash percent determinations in order to reduce the uncertainties. collection of representative straw samples is shown to make higher demands to the sampling procedure than collection of those for coal. A representative sample collection is shown to be easier from combustion experiments that form gasification and pyrolysis experiments. The ash tracer technique is verified by elemental ash analyses. (au) 14 tabs., 6 refs.

  17. Cellulase activity of filamentous fungi induced by rice husk | Oliveros ...

    African Journals Online (AJOL)

    The objective of this study was to determine the potential of different filamentous fungi to degrade cellulose in rice husk pre-treated with steam explosion or alkaline hydrolysis. A preliminary test performed with carboxymethyl cellulose and nine fungi (Trichoderma 1, 2, 3, 4, 5; Trichoderma reesei; Aspergillus niger; Rhizopus ...

  18. Comparative utilization of biodegraded and undegraded rice husk in ...

    African Journals Online (AJOL)

    Possible improvement in the nutritional composition of rice husk (RH) was attempted through Solid State Fermentation with the use of the fungus, Trichoderma viridii. A comparative utilization of the fermented RH (FRH), raw RH and a control diet was studied using parameters like performance and nutrient utilization ...

  19. Feeding Rice Husk-Poultry Manure with and without Enzyme ...

    African Journals Online (AJOL)

    A total of thirty-six (36) rabbits of mixed sexes were used in a ten (10) week feeding trials to investigate the relative effect of dietary levels of rice husk poultry manure (RHPM) supplemented with or without β-xylanase. The rabbits were randomly allotted into six (6) dietary treatment groups of 0, 10 and 20% of RHPM with or ...

  20. Effects of Feeding High Level of Cowpea Husk on the ...

    African Journals Online (AJOL)

    This study was conducted at Usmanu Danfodiyo University, Sokoto, to find out the effect of feeding high levels of cowpea husk on the haematological parameters and Blood urea nitrogen of Uda lambs. Fifteen (15) weeks feeding trial (including three (3) weeks digestibility trial) was conducted using sixteen (16) growing Uda ...

  1. Novel herbal adsorbent based on wheat husk for reactive dye ...

    African Journals Online (AJOL)

    In the present study, wheat husk was applied as a natural adsorbent for the dye C. I. Reactive Yellow 15 removal from aqueous solutions. Different effective parameters of the decolorisation process such as contact time, stirring speed, temperature and pH of solutions were studied and the best condition for achieving the ...

  2. Pyrolysis kinetics of hazelnut husk using thermogravimetric analysis.

    Science.gov (United States)

    Ceylan, Selim; Topçu, Yıldıray

    2014-03-01

    This study aims at investigating physicochemical properties and pyrolysis kinetics of hazelnut husk, an abundant agricultural waste in Turkey. The physicochemical properties were determined by bomb calorimeter, elemental analysis and FT-IR spectroscopy. Physicochemical analysis results showed that hazelnut husk has a high calorimetric value and high volatile matter content. Pyrolysis experiments were carried out in a thermogravimetric analyzer under inert conditions and operated at different heating rates (5, 10, 20°C/min). Three different kinetic models, the iso-conversional Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) models and Coats-Redfern method were applied on TGA data of hazelnut husk to calculate the kinetic parameters including activation energy, pre-exponential factor and reaction order. Simulation of hazelnut husk pyrolysis using data obtained from TGA analysis showed good agreement with experimental data. Combining with physicochemical properties, it was concluded that this biomass can become useful source of energy or chemicals. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Proximate composition and amino acid profile of rice husk ...

    African Journals Online (AJOL)

    Native rice husk (NRH) was fermented with Pleurotus ostreatus for 7, 14 and 21 days to improve the nutritional values. The proximate composition and amino acid profiles were determined. The results showed that crude fibre (CF), nitrogen free extract (NFE), acid detergent fibre (ADF), and neutral detergent fibre (NDF) were ...

  4. Effect of Pleurotus ostreatus fermentation on cocoa pod husk ...

    African Journals Online (AJOL)

    Cocoa pod husk (CPH) is a major agro-industrial residue in Ghana with a potential value as a low-cost unconventional feedstuff for livestock. However, its effective use is limited by poor nutrient composition, mainly due to its high lignocellulose or fibre and also low protein levels. White–rot fungi such as Pleurotus species ...

  5. Development of a method for the mineralization of coffee husk ...

    African Journals Online (AJOL)

    Every year, large quantities of husk resulting from the dry method of treatment of robusta coffee are dumped into nature. This generates multiple harmful ecological effects. The downward trend of coffee prices and the rise in the cost of manure has urged coffee farmers to better exploit the by-products of coffee transformation.

  6. ANALYSIS OF THE HUSK AND KERNEL OF THE SEEDS OF ...

    African Journals Online (AJOL)

    results showed the presence of diverse fatty acids namely palmitic (11%), palmitoleic (1.2%), stearic (11%), oleic. (63%), linoleic (1.2%), arachidic (6%) and the rare behenic acids (6%). The white glossy seed husk ... It is also used to heal stomach-ache and expel retaining placenta in women. [4]. Pharmacological reports ...

  7. Removal of arsenic from drinking water using rice husk

    Science.gov (United States)

    Asif, Zunaira; Chen, Zhi

    2017-06-01

    Rice husk adsorption column method has proved to be a promising solution for arsenic (As) removal over the other conventional methods. The present work investigates the potential of raw rice husk as an adsorbent for the removal of arsenic [As(V)] from drinking water. Effects of various operating parameters such as diameter of column, bed height, flow rate, initial arsenic feed concentration and particle size were investigated using continuous fixed bed column to check the removal efficiency of arsenic. This method shows maximum removal of As, i.e., 90.7 % under the following conditions: rice husk amount 42.5 g; 7 mL/min flow rate in 5 cm diameter column at the bed height of 28 cm for 15 ppb inlet feed concentration. Removal efficiency was increased from 83.4 to 90.7 % by reducing the particle size from 1.18 mm to 710 µm for 15 ppb concentration. Langmuir and Freundlich isotherm models were employed to discuss the adsorption behavior. The effect of different operating parameters on the column adsorption was determined using breakthrough curves. In the present study, three kinetic models Adam-Bohart, Thomas and Yoon-Nelson were applied to find out the saturated concentration, fixed bed adsorption capacity and time required for 50 % adsorbate breakthrough, respectively. At the end, solidification was done for disposal of rice husk.

  8. The economic implication of substituting cocoa pod husk for maize ...

    African Journals Online (AJOL)

    A study was conducted to estimate the amount of maize that could be conserved by substituting cocoa pod husk (CPH) for maize in livestock feeds. For this purpose a conversion coefficient between dry cocoa beans and dry CPH was estimated by using data collected from a survey of 50 cocoa farms. Some livestock feed ...

  9. Chemical and antimicrobial analysis of husk fiber aqueous extract ...

    African Journals Online (AJOL)

    Chemical and antimicrobial analysis of husk fiber aqueous extract from Cocos nucifera L. Davi Oliveira e Silva, Gabriel Rocha Martins, Antônio Jorge Ribeiro da Silva, Daniela Sales Alviano, Rodrigo Pires Nascimento, Maria Auxiliadora Coelho Kaplan, Celuta Sales Alviano ...

  10. Effects of locust bean pulp with melon husk supplementation on ...

    African Journals Online (AJOL)

    The effect of locust bean pulp with melon husk supplementation on nitrogen utilization and blood chemistry of West African Dwarf goats were assessed in a 3 months feeding trial. Eighteen West African Dwarf goats with an average weight of 6.00 ± 0.15kg were randomly allotted to three dietary treatments with two replicates ...

  11. Antimicrobial properties of coconut husk aqueous extract on cariogenic bacteria

    Directory of Open Access Journals (Sweden)

    Maria B Cyriac

    2013-01-01

    Full Text Available Background and Objectives: The husk fibers of coconut (Cocos nucifera are reported to be used by people of rural areas of South India for daily cleaning their teeth. As the beneficial effects of this plant material, with respect to antimicrobial properties against common cariogenic bacteria, are not scientifically proven, the present study was conducted. Materials and Methods: The husk of coconut was collected and aqueous extract was prepared and antimicrobial properties against common oral pathogens like Streptococcus mutans, Streptococcus salivarius, Streptococcus mitis, and Lactobacillus acidophilus were performed by agar well diffusion method. The values obtained were then subjected to statistical analysis using one way ANOVA and Tukey HSD. Results: Aqueous extract of coconut husk showed a concentration-dependent antimicrobial activity against different tested organisms with zone of inhibition ranging from 4.44 to 15.33 mms. However, the efficacy was less in comparison to chlorhexidine. Conclusion: Inhibitory action against cariogenic bacteria exhibited by aqueous extract of coconut husk indicate presence of highly effective active compounds in these extracts, which can be identified and incorporated into modern oral care systems for controlling dental caries.

  12. Evaluation of gamma-irradiation in cocoa husk.

    Science.gov (United States)

    Bonvehí, J S; Isal, D G

    2000-06-01

    gamma-Irradiation was investigated as a technique to improve the hygienic quality of cocoa husk. Cocoa husk is a byproduct of cocoa bean processing industry. It contains approximately 57.5% (w/w) dietary fiber (nonstarch polysaccharides plus lignin), 15% (w/w) crude protein, 10.7% (w/w) mineral elements, 2.32% (w/w) cocoa butter, and 2.8% (w/w) carbohydrates (free sugars plus starch). The effect of irradiation on the growth rates of microorganisms are reported. Total counts, enterobacteriaceae, coliforms, Staphylococcus aureus, Streptococcus "D" of Lancefield, and yeast and mold counts before and after irradiation at 5, 8, and 10 kGy were determined. Cocoa husk was irradiated in open containers. An irradiation dose of 5 kGy was already sufficient to decrease the microbial counts to a very low level. No alteration in dietary fiber was measured in the irradiated product and no significant differences were detected between irradiated and nonirradiated cocoa husk.

  13. Storage period, husking and seed treatment effects on germination ...

    African Journals Online (AJOL)

    Seed dormancy is among the major problems associated with pasture establishment from Rhodes grass. Two experiments were conducted with the aim to assess the effects of storage period (years), husking and seed treatment on germination rate of Rhodes grass seeds of two cultivars, Callide and Masaba, at Kulumsa ...

  14. Addition of ash on drained forested peatlands in southern Sweden. Effects on forest production, fluxes of greenhouse gases, peat properties, understorey vegetation and groundwater chemistry; Tillfoersel av aska i skog paa dikad torvmark i soedra Sverige. Effekter paa skogsproduktion, floeden av vaexthusgaser, torvegenskaper, markvegetation och grundvattenkemi

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem, Ulf; Bjoerk, Robert G.; Ring, Eva; Ernfors, Maria; Jacobson, Staffan; Nilsson, Mats; Klemedtsson, Leif

    2009-02-15

    The objective of the present study was to evaluate effects of wood-ash addition on drained peatlands in southern Sweden. Tree growth, greenhouse gases, peat properties, microbial biomass and processes, understory vegetation and groundwater chemistry were measured in three field experiments (some variables were not measured in all experiments): (i) 168 Perstorp, an oligotrophic mire with Scotch pine (Pinus sylvestris L.), where 2.5 tonnes d.w. of wood ash/ha (2.5WA) was added in 1982; (ii) 273 Anderstorp, also an oligotrophic mire with Scots pine, where 3.3 tonnes d.w. crushed ash/ha (3.3KA) and 6.6 tonnes d.w. crushed/ha (6.6KA) was added in 2003; (iii) 278 Skogaryd, a minerotrophic mire with Norway spruce (Picea abies L. Karst.), where the same doses of crushed ash as in Anderstorp were added in 2006. Untreated controls were included in all experiments. At Anderstorp, increased tree growth was indicated, at least in the treatment with the highest ash dose during the first five years after treatment. The annual emissions of CO{sub 2}, CH4 and N{sub 2}O from the peat were unaffected. At Skogaryd, the growth was unaffected and the emissions of both CO{sub 2} and N{sub 2}O were reduced during the first two years after treatment. In general, the significant ash effects (2.5WA and 3.3KA evaluated) on peat characteristics, microbial biomass and processes were found in the upper soil (0-5 cm) at the recently treated sites (Anderstorp and Skogaryd), and at greater depths (5-30 cm) at Perstorp, where the ash was added 25 years ago. In the ash treatment at Perstorp, there was a shift in the plant community structure and a decrease in species diversity of the understory vegetation. However, at this point of time, the forest stand had become substantially denser than on the control plots. Hence, these effects on the understory vegetation may have been an indirect effect of the ash-induced altered tree stand properties. In Skogaryd, no shift in the plant community was found

  15. Melting and Sintering of Ashes

    DEFF Research Database (Denmark)

    Hansen, Lone Aslaug

    1997-01-01

    The thesis contains an experimental study of the fusion and sintering of ashes collected during straw and coal/straw co-firing.A laboratory technique for quantitative determination of ash fusion has been developed based on Simultaneous Thermal Analysis (STA). By means of this method the fraction...... of melt in the investigated ashes has been determined as a function of temperature. Ash fusion results have been correlated to the chemical and mineralogical composition of the ashes, to results from a standard ash fusion test and to results from sintering experiments. Furthermore, the ash fusion results...... have been employed in a simple model for prediction of ash deposit formation, the results of which have been compared to ash deposition formation rates measured at the respective boilers.The ash fusion results were found to directly reflect the ash compositional data:a) Fly ashes and deposits from...

  16. Influence of Using Rice Husk Ash in Soil Stabilization Method with Lime

    DEFF Research Database (Denmark)

    Choobbasti, A. J.; Ghodrat, H.; Vahdatirad, Mohammadjavad

    2010-01-01

    Situated at the junction of land and sea, coastal salt marshes are very sensitive to global environmental changes. Existing numerical models simulating the vertical growth of coastal salt marshes are under the conditions of low suspended sediment concentration (SSC), but under high SSC, such as i...

  17. Efficacy of rice husk ash against rice weevil and lesser grain borer ...

    African Journals Online (AJOL)

    The objective of this study was to determine efficacy of RHA from “Mr. Harry” rice variety against Rhyzopertha dominica and Sitophilus oryzae. Low (RHAL) and high (RHAH) application rates of RHA, corresponding to 0.5 and 1 g kg-1, respectively, were evaluated against both weevils on wheat. Insecto®, a commercial DE, ...

  18. effect of aluminum dross and rice husk ash on thermal and moulding

    African Journals Online (AJOL)

    HOD

    Moulding properties of foundry sand should be controlled so as to minimize casting defects. Its thermal characteristics are vital in defining the solidification kinetics of a cast part, evolving microstructure and mechanical properties. Modification of the thermal properties of the moulding sand mix is important in achieving ...

  19. Synthesis of ternary geopolymers based on metakaolin, boiler slag and rice husk ash

    Directory of Open Access Journals (Sweden)

    Mónica Alejandra Villaquirán-Caicedo

    2015-01-01

    Full Text Available Mezclas ternarias de geopolímeros fueron obtenidas a partir de la activación alcalina de metacaolín (MK, ceniza de parrilla (BS usando como activador alcalino una mezcla de hidróxido de potasio con ceniza de cascarilla de arroz (RHA. Los materiales producidos fueron caracterizados mecánica, térmica y microestructuralmente. Las propiedades de los geopolímeros y microestructura final indica que la adición de la escoria de parrilla (con grandes cantidades de material sin quemar, 16.36%, permite un mayor grado densificación y una mayor homogeneidad del geopolímero, resultando en una mayor estabilidad de la resistencia para largas edades. La sustitución del 30% del MK por BS genera un incremento de la resistencia a compresión hasta del 21% y 122% después de 28 y 180 días de curado respectivamente. Los resultados aquí obtenidos demuestran la posibilidad de usar geopolímeros basados en MK son adición de BS y RHA en el sector de la construcción para obtener materiales cementicios con bajo impacto ambiental.

  20. the potential use of fonio husk ash as a pozzolana in concrete

    African Journals Online (AJOL)

    eobe

    2016-01-01

    Jan 1, 2016 ... combined percent of SiO2, Al2O3 and Fe2O3 of 71.14% is above the 70% benchmark for a pozzolana material. The. Initial and Final Setting Times ... cheap and available pozzolanic materials from agro wastes. Results of a report [1] on the ..... Mechanics & Materials, Vol. 679, 2014, p. 228. [11] Hashem, F.

  1. Ultra high performance concrete made with rice husk ash for reduced autogenous shrinkage

    NARCIS (Netherlands)

    Van Breugel, K.; Van Tuan, N.

    2014-01-01

    Ultra High Strength Concrete (UHPC) is generally made with low w/c mixtures and by adding silica fume. Low w/c mixtures, however, exhibit high autogenous shrinkage, while a high amount of silica fume increases the price of these mixtures. For designing ultra high strength mixtures with low

  2. efficacy of rice husk ash against rice weevil and lesser grain borer

    African Journals Online (AJOL)

    ACSS

    @ a causé une mortalité de 63,4% and 100% chez R. dominica et S. oryzae, .... their chemical composition (Acme Analytical. Laboratories Ltd, Vancouver, Canada). This involved analysis of 0.1-g samples using. Inductively Coupled Plasma ...

  3. utilisation of rice husk ash for improvement of deficient soils in ...

    African Journals Online (AJOL)

    user

    provision of stable and durable geotechnical structures, reduce cost of soil improvement and the environmental nuisance caused by the unused waste. This will .... tests at British Standard Light (BSL) compaction energy. Results obtained, indicate a ..... Structural, Construction and Architectural. Engineering, vol. 9(11): pp.

  4. Effects of Rice Husk Ash on Some Geotechnical Properties of Lateritic Soil

    Directory of Open Access Journals (Sweden)

    Fidelis O. OKAFOR

    2009-12-01

    Full Text Available The study is an investigation into the effect of RHA on some geotechnical properties of a lateritic soil classified as A-2-6 (0 or SW for sub-grade purposes. The investigation includes evaluation of properties such as compaction, consistency limits and strength of the soil with RHA content of 5%, 7.5%, 10% and 12.5% by weight of the dry soil. The results obtained show that the increase in RHA content increased the OMC but decreased the MDD. It was also discovered that increase in RHA content, reduced plasticity and increased volume stability as well as the strength of the soil. 10% RHA content was also observed to be the optimum content.

  5. 23 Effects of Groundnut Husk Ash-blended Cement on Chemical ...

    African Journals Online (AJOL)

    Arc. Usman A. Jalam

    mortar cubes of 50mm, exposed to sodium sulphate solution of varying concentrations of. 1.0%, 1.5% ... performance of mortar and concrete containing trass and ultra fine filler was better than the control ..... International Centre for Sustainable Development of. Cement and Concrete (ICON), CANMET, Natural Resources ...

  6. Arsenate adsorption onto iron oxide amended rice husk char.

    Science.gov (United States)

    Cope, Christopher O; Webster, Damon S; Sabatini, David A

    2014-08-01

    In this study, rice husks were charred at 550 °C in a partially sealed ceramic vessel for 30minutes to create a high specific surface area (SSA) rice husk char (RHC). The RHC was then amended with iron oxides using dissolved ferric nitrate, Fe(NO3)3⋅9H2O, to provide a surface chemistry conducive to arsenic adsorption. The 550 °C iron oxide amended rice husk char's (550 IOA-RHC's) SSA was nearly 2.5 orders of magnitude higher and the arsenate adsorptive level was nearly 2 orders of magnitude higher than those reported for iron oxide amended sand, thus indicating a positive relationship between post-amendment SSA and arsenate adsorptive levels. Rice husks were then charred at temperatures ranging from 450 °C to 1050 °C to create an even higher SSA material, which might further increase arsenate adsorptive levels. The 950 °C RHC was chosen for amendment due to its high SSA and feasibility of being produced in the field. Once amended, the 950 °C iron oxide amended rice husk char (950 IOA-RHC) improved the arsenate adsorption capacity by thus confirming a positive relationship, though not a linear relationship, between post-amendment SSA and arsenic adsorptive capacity. Further study demonstrated that post-amendment mesoporous volume and mesoporous surface area appear to be better indicators of arsenic adsorptive capacity than SSA or iron content. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Slowing ash mortality: a potential strategy to slam emerald ash borer in outlier sites

    Science.gov (United States)

    Deborah G. McCullough; Nathan W. Siegert; John Bedford

    2009-01-01

    Several isolated outlier populations of emerald ash borer (Agrilus planipennis Fairmaire) were discovered in 2008 and additional outliers will likely be found as detection surveys and public outreach activities...

  8. Trace elements in coal ash

    Science.gov (United States)

    Deonarine, Amrika; Kolker, Allan; Doughten, Michael W.

    2015-01-01

    Coal ash is a residual waste product primarily produced by coal combustion for electric power generation. Coal ash includes fly ash, bottom ash, and flue-gas desulfurization products (at powerplants equipped with flue-gas desulfurization systems). Fly ash, the most common form of coal ash, is used in a range of products, especially construction materials. A new Environmental Protection Agency ruling upholds designation of coal ash as a non-hazardous waste under Subtitle D of the Resource Conservation and Recovery Act, allowing for the continued beneficial use of coal ash and also designating procedures and requirements for its storage.

  9. Effects of nano-SiO(2) and different ash particle sizes on sludge ash-cement mortar.

    Science.gov (United States)

    Lin, K L; Chang, W C; Lin, D F; Luo, H L; Tsai, M C

    2008-09-01

    The effects of nano-SiO(2) on three ash particle sizes in mortar were studied by replacing a portion of the cement with incinerated sewage sludge ash. Results indicate that the amount of water needed at standard consistency increased as more nano-SiO(2) was added. Moreover, a reduction in setting time became noticeable for smaller ash particle sizes. The compressive strength of the ash-cement mortar increased as more nano-SiO(2) was added. Additionally, with 2% nano-SiO(2) added and a cure length of 7 days, the compressive strength of the ash-cement mortar with 1 microm ash particle size was about 1.5 times better that of 75microm particle size. Further, nano-SiO(2) functioned to fill pores for ash-cement mortar with different ash particle sizes. However, the effects of this pore-filling varied with ash particle size. Higher amounts of nano-SiO(2) better influenced the ash-cement mortar with larger ash particle sizes.

  10. Nano-silicate inhibitor derived from rice husk for corrosion mitigation of steel in distilled water

    Science.gov (United States)

    Asra, Denni; Othman, Norinsan Kamil; Dasuki, Zulhusni

    2017-05-01

    Nanosilicate extracts from rice husk (Oryza sativa L.) ash (RHA) as a corrosion inhibitor for carbon steel in distilled water has been investigated. The nanosilicates extracted from RHA was obtained through wet chemical extraction and the extracted nanosilicates powder were analyzed using Fourier Transform Infrared Spectroscopy (FTIR) in order to identify the presence of functional groups (SiO2) that contributed to the inhibition process. The particle size of extracted nanosilica is in the range of 5-10 nm and it was confirmed through Transmission electron microscopy (TEM) and Zeta Sizer analysis. The corrosion measurement study on the effect of nanosilicate from RHA on carbon steel samples in distilled water as corrosive media had been conducted by employing weight loss method, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), surface analysis, and adsorption isotherm study. It was proven that the maximum inhibition efficiency (IE %) obtained through corrosion measurement were up to 98 % of inhibition. On the other hand, the adsorption of inhibitor on the carbon steel surface was found to follow Temkin isotherm. Based on the result of potentiodynamic polarization, it showed that inhibitors are mixed type. The results of EIS showed that value of charge transfer resistance and the percentage of inhibition efficiency increased with the increasing of nanosilicate concentration. Surface analysis on specimen that was treated with nanosilicate were smoother with fewer corrosion products compared to untreated specimen.

  11. Beyond waste: new sustainable fillers from fly ashes stabilization, obtained by low cost raw materials

    Directory of Open Access Journals (Sweden)

    N. Rodella

    2016-09-01

    Full Text Available A sustainable economy can be achieved only by assessing processes finalized to optimize the use of resources. Waste can be a relevant source of energy thanks to energy-from-waste processes. Concerns regarding the toxic fly ashes can be solved by transforming them into resource as recycled materials. The commitment to recycle is driven by the need to conserve natural resources, reduce imports of raw materials, save landfill space and reduce pollution. A new method to stabilize fly ash from Municipal Solid Waste Incinerator (MSWI at room temperature has been developed thanks to COSMOS-RICE LIFE+ project (www.cosmos-rice.csmt.eu. This process is based on a chemical reaction that occurs properly mixing three waste fly ashes with rice husk ash, an agricultural by-product. COSMOS inert can replace critical raw materials (i.e. silica, fluorspar, clays, bentonite, antimony and alumina as filler. Moreover the materials employed in the stabilization procedure may be not available in all areas. This paper investigates the possibility of substituting silica fume with corresponding condensed silica fume and to substitute flue-gas desulfurization (FGD residues with low-cost calcium hydroxide powder. The removal of coal fly ash was also considered. The results will be presented and a possible substitution of the materials to stabilize fly ash will be discussed.

  12. Reduction of metal leaching in brown coal fly ash using geopolymers.

    Science.gov (United States)

    Bankowski, P; Zou, L; Hodges, R

    2004-10-18

    Current regulations classify fly ash as a prescribed waste and prohibit its disposal in regular landfill. Treatment of the fly ash can reduce the leach rate of metals, and allow it to be disposed in less prescribed landfill. A geopolymer matrix was investigated as a potential stabilisation method for brown coal fly ash. Precipitator fly ash was obtained from electrostatic precipitators and leached fly ash was collected from ash disposal ponds, and leaching tests were conducted on both types of geopolymer stabilised fly ashes. The ratio of fly ash to geopolymer was varied to determine the effects of different compositions on leaching rates. Fourteen metals and heavy metals were targeted during the leaching tests and the results indicate that a geopolymer is effective at reducing the leach rates of many metals from the fly ash, such as calcium, arsenic, selenium, strontium and barium. The major element leachate concentrations obtained from leached fly ash were in general lower than that of precipitator fly ash. Conversely, heavy metal leachate concentrations were lower in precipitator fly ash than leached pond fly ash. The maximum addition of fly ash to this geopolymer was found to be 60wt% for fly ash obtained from the electrostatic precipitators and 70wt% for fly ash obtained from ash disposal ponds. The formation of geopolymer in the presence of fly ash was studied using 29Si MAS-NMR and showed that a geopolymer matrix was formed. X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) imaging showed the interaction of the fly ash with the geopolymer, which was related to the leachate data and also the maximum percentage fly ash addition.

  13. Oxidative stability of soybean oil added to coffee husk extract (Coffea arabica L. under accelerated storage conditions

    Directory of Open Access Journals (Sweden)

    Elisa Franco RIBEIRO

    Full Text Available Abstract Several plants have been studied as potential sources of natural antioxidants for use in the food industry, especially polyphenols. The aim of this study was to evaluate the effects of hydroalcoholic extract from coffee husk on the oxidative stability of soybean oil when stored in an oven. Samples were maintained at a temperature of 60 °C and their oxidative stability was evaluated once every 5 days for a period of 20 days through the Rancimat equipament and analysis of peroxide value, conjugated dienes and tocopherols retention. The oxidation rate in terms of mass gain was evaluated once every 24 hours for a period of 24 days. Although the antioxidant TBHQ showed a better efficiency in the inhibition of oxidation, coffee husk extract showed a synergistic effect when used with the synthetic, delaying the appearance of degradation products. In addition, the freeze-dried extract showed the ability to reduce the mass-gain rate when used alone as well as when used in combination with the synthetic antioxidant butyl hydroxyanisole (BHA, noting a synergistic effect on oxidative stability between the extract and the BHA. Therefore, coffee husk extract could be considered a source of natural antioxidants for synthetic antioxidants substitution.

  14. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    Science.gov (United States)

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-07-01

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO 2 and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 °C for 2-6 h by changing the SiO 2/Al 2O 3, H 2O/Na 2O and Na 2O/SiO 2 molar ratios of precursors in the two-step process. The surface area and NH 4+-cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m 2/g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m 2/g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of ˜3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously.

  15. Application studies of activated carbon derived from rice husks produced by chemical-thermal process--a review.

    Science.gov (United States)

    Chen, Yue; Zhu, Yanchao; Wang, Zichen; Li, Ying; Wang, Lili; Ding, Lili; Gao, Xiaoyan; Ma, Yuejia; Guo, Yupeng

    2011-03-15

    The production of functional activated carbon materials starting from cheap natural precursors using environmentally friendly processes is a highly attractive subject in material chemistry today. Recently, much attention has been focused on the use of plant biomass to produce functional carbonaceous materials, encompassing economic, environmental and social issues. Besides the classical route to produce activated carbons from fossil materials, rice husk shows clear advantages in that it can generate a variety of cheap and sustainable carbonaceous materials with attractive nanostructure and functional patterns for a wide range of applications. From a comprehensive literature review, it was found that porous carbon that derived from rice husks, in addition to having wide availability, has fast kinetics and appreciable adsorption capacities too. Porous carbon materials also play a significant role in new applications such as catalytic supports, battery electrodes, capacitors, and gas storage. In this review, an extensive list of rice husks literature has been compiled. Conclusions have been drawn from the literature reviewed, and suggestions for future research are proposed. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. [Adsorption-desorption Characteristics of Fermented Rice Husk for Ferrous and Sulfur Ions].

    Science.gov (United States)

    Xie, Xiao-mei; Liao, Min; Hua, Jia-yuan; Chen, Na; Zhang, Nan; Xu, Pei-zhi; Xie Kai-zhi; XU, Chang-xu; Liu, Guang-rong

    2015-10-01

    To understand the potential of rice husk to fix Fe2+ and S2- ions, the sorption of Fe2+ and S2- by fermented rice husk was studied by using batch incubation experiments in the present study. The effects of adsorption time, Fe2+ and S2- concentration, pH, the temperature and ionic strength in adsorption reaction solution on the sorption were investigated. Therefore, the stability of Fe2+ and S2- adsorbed by fermented rice husk was further validated by desorption experiments performed under similar conditions as adsorption. The results showed that, the adsorption kinetics of Fe2+ (r = 0.912 1) and S2- (r = 0.901 1) by fermented rice husk fits the Elovich kinetics equation, and Freundlich isotherm model could simulate the isotherm adsorption processes of Fe2+ (R2 = 0.965 1) and S2- (R2 = 0.936 6) on fermented rice husk was better than other models. The adsorption processes on fermented rice husk were non- preferential adsorption for Fe2+ and S2, while the adsorption process of Fe2+ on fermented rice husk was spontaneous reaction and the adsorption process of S2- was non-spontaneous reaction. The adsorption processes of Fe2+ and S2- on fermented rice husk were endothermic process since high temperature could benefit to the adsorption. The adsorption mechanism of Fe2+ on fermented rice husk was mainly controlled by coordination adsorption, the adsorption mechanism of S2- on fermented rice husk was mainly controlled by ligand exchange adsorption. The adsorption processes of Fe2+ and S2- on fermented rice husk showed greater pH adaptability which ranged from 1.50 to 11.50. With the increasing of ionic strength, the amount of adsorbed Fe2+ on fermented rice husk wasincreased in some extent, the amount of adsorbed S2- on fermented rice husk was slightly decreased, which further proved the adsorption of Fe2+ was major in inner sphere complexation and the adsorption of S2- was major in outer complexation. The desorption rates of Fe2+ and S2- which was adsorbed by fermented

  17. A gastroretentive drug delivery system of lisinopril imbibed on isabgol-husk.

    Science.gov (United States)

    Semwal, Ravindra; Semwal, Ruchi Badoni; Semwal, Deepak Kumar

    2014-01-01

    The gastroretentive drug delivery system is site-specific and allows the drug to remain in the stomach for a prolonged period of time so that it can be released in a controlled manner in gastrointestinal tract. The present study was carried out to develop a gastroretentive drug delivery system using isabgol as an excipient to prolong the residence time of the model drug lisinopril in the stomach. The gastroretentive ability of isabgol was increased by addition of NaHCO3 as a gas-generating agent while its mucoadhesive property was enhanced by incorporation of HPMC-K4M. The drug, NaHCO3 and HPMC-K3M were imbibed on isabgol-husk as per entrapment efficiency of the isabgol-husk. After drying, the product was filled in a hard gelatin capsule and evaluated for its buoyancy, mucoadhesive properties, swelling index and in vitro drug release. The lisinopril released through isabgol was delayed by 12 hours when compared to a preparation available on the market which released the complete drug in 0.5 hours. The drug release study of lisinopril from the formulation follows first order kinetics using a diffusion controlled mechanism. The results from the present study revealed that isabgol can be used as a potential excipient for the formulation of gastroretentive drug delivery systems in the near future.

  18. Reforming social services: the institutional and organizational context of the HUSK program.

    Science.gov (United States)

    Andreassen, Tone Alm

    2015-01-01

    In this article the author provides an analysis of: (a) the institutional context that gave rise to the HUSK program, (b) the character of the HUSK program, and (c) the consequences of the reform of the organizational context in which the HUSK program was implemented-the fundamental reorganization of the labor and welfare services which occurred as a result of the "NAV reform." Local social insurance services, employment services, and social welfare services were merged into one joint NAV office. While the NAV reform was focused on organizational restructuring and integration of three formerly separate services, the HUSK program was focused on development of the professional competence of social workers only and on extensive service user involvement. While HUSK, based on the logic of professionalism, could bypass organization, the NAV reform placed the logic of organization at the forefront. The NAV reform and the HUSK program became parallel developmental processes with weak ties.

  19. assessment of assessment of bagasse ash bagasse ash bagasse ...

    African Journals Online (AJOL)

    eobe

    This study was carried out to evaluate the effect of bagasse ash s carried out to evaluate the effect of bagasse ash s carried out to evaluate the effect of bagasse ash on the California bearing ratio of lateritic soil. on the California bearing ratio of lateritic soil. Laboratory tests were performed on the natural and bagasse ash ...

  20. A Comprehensive Review on the Properties of Coal Bottom Ash in Concrete as Sound Absorption Material

    National Research Council Canada - National Science Library

    Nurul Izzati Raihan Ramzi Hannan; Shahiron Shahidan; Noorwirdawati Ali; Mohamad Zulkhairi Maarof

    2017-01-01

    .... At the same time, the dependency on gas will be reduced. In addition, coal power plants in Malaysia produce large amounts of industrial waste such as bottom ash which is collected in impoundment ponds (ash pond...

  1. Characteristics of a β-1,4-D endoglucanase from Trichoderma virens wholly applied in a palm-fruit husk-based diet for poultry layers

    Directory of Open Access Journals (Sweden)

    Olubusola A. Odeniyi

    2012-12-01

    Full Text Available The characteristics of an endoglucanase produced by a Trichoderma virens strain T9 newly isolated from a palm-fruit husk dump site, its physiological characteristics and enzyme production were studied. Whole cells of the depolymerizing-enzyme producing T. virens were applied to palm-fruit husk and bird performance characteristics when employed as poultry diet additive were considered. Endoglucanase activity in submerged fermentation was 1.6 nkat. Optimum activity was recorded at pH 6.0 and 55ºC. The enzyme retained 50% residual glucanase activity at 70ºC for 10 minutes. 1.0% Tween-80 and SDS yielded endoglucanase activity 2.15 times higher than the control. Activity wasboosted by 20mM Ca2+ (115.0%; 10mM K+ (106.5%; and was totally inhibited by 1mM Hg2+. The addition of T. virens -fermented palm-fruit husk with other layer feed components on the bird characteristics showed that change in bird weight between the control and test birds were not significantly different (p>0.05 but differed in terms of daily feed ingested (p0.05. The shell thickness (0.64mm and yolk content (23.61% were highest in the microbially-modified husk diet. The alternative to maize based diets proffered by the application of T. virens -modified palm-fruit husk in poultry nutrition in terms of bird weight and feed to weight-gain ratio affords the poultry farmer an economic advantage and allows for a greater utilization of the maize in human diets.

  2. SLAM: A multi-agency pilot project to SL.ow A.sh M.ortality caused by emerald ash borer in outlier sites

    Science.gov (United States)

    Therese M. Poland; Deborah G. McCullough

    2010-01-01

    Since its discovery in southeast Michigan in 2002, the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), has continued to spread and kill ash (Fraxinus) trees at an alarming rate. As of February 2010, EAB has killed tens of millions of ash trees in Michigan, at least 12 additional U.S. states, and the...

  3. Fundamental Study of Low NOx Combustion Fly Ash Utilization

    Energy Technology Data Exchange (ETDEWEB)

    E. M. Suubert; I. Kuloats; K. Smith; N. Sabanegh; R.H. Hurt; W. D. Lilly; Y. M. Gao

    1997-05-01

    This study is principally concerned with characterizing the organic part of coal combustion fly ashes. High carbon fly ashes are becoming more common as by-products of low-NOx combustion technology, and there is need to learn more about this fraction of the fly ash. The project team consists of two universities, Brown and Princeton, and an electrical utility, New England Power. A sample suite of over forty fly ashes has been gathered from utilities across the United States, and includes ashes from a coals ranging in rank from bituminous to lignite. The characterizations of these ashes include standard tests (LOI, Foam Index), as well as more detailed characterizations of their surface areas, porosity, extractability and adsorption behavior. The ultimate goal is, by better characterizing the material, to enable broadening the range of applications for coal fly ash re-use beyond the current main market as a pozzolanic agent for concretes. The potential for high carbon-content fly ashes to substitute for activated carbons is receiving particular attention. The work performed to date has already revealed how very different the surfaces of different ashes produced by the same utility can be, with respect to polarity of the residual carbon. This can help explain the large variations in acceptability of these ashes as concrete additives.

  4. Fundamental Study of Low-Nox Combustion Fly Ash Utilization

    Energy Technology Data Exchange (ETDEWEB)

    E. M. Suuberg; I. Kuloats; K. Smith; N. Sabanegh; R. H. Hurt; W. D. Lilly; Y. M. Gao

    1997-11-01

    This study is principally concerned with characterizing the organic part of coal combustion fly ashes. High carbon fly ashes are becoming more common as by-products of low-NOx combustion technology, and there is need to learn more about this fraction of the fly ash. The project team consists of two universities, Brown and Princeton, and an electrical utility, New England Power. A sample suite of over forty fly ashes has been gathered from utilities across the United States, and includes ashes from a coals ranging in rank from bituminous to lignite. The characterizations of these ashes include standard tests (LOI, Foam Index), as well as more detailed characterizations of their surface areas, porosity, extractability and adsorption behavior. The ultimate goal is, by better characterizing the material, to enable broadening the range of applications for coal fly ash re-use beyond the current main market as a pozzolanic agent for concretes. The potential for high carbon-content fly ashes to substitute for activated carbons is receiving particular attention. The work performed to date has already revealed how very different the surfaces of different ashes produced by the same utility can be, with respect to polarity of the residual carbon. This can help explain the large variations in acceptability of these ashes as concrete additives.

  5. Fusion characterization of biomass ash

    DEFF Research Database (Denmark)

    Ma, Teng; Fan, Chuigang; Hao, Lifang

    2016-01-01

    characteristics of six types of biomass ash have been measured by TMA. Compared with standard ash fusibility temperatures (AFT) test, TMA is more suitable for measuring the fusion characteristics of biomass ash. The glassy molten areas of the ash samples are sticky and mainly consist of K-Ca-silicates....

  6. Coffee husk waste for fermentation production of mosquitocidal bacteria.

    Science.gov (United States)

    Poopathi, Subbiah; Abidha, S

    2011-12-01

    Coffee husk waste (CHW) discarded as bio-organic waste, from coffee industries, is rich in carbohydrates. The current study emphasizes the management of solid waste from agro-industrial residues for the production of biopesticides (Bacillus sphaericus, and B. thuringiensis subsp. israelensis), to control disease transmitting mosquito vectors. An experimental culture medium was prepared by extracting the filtrates from coffee husk. A conventional culture medium (NYSM) also was prepared. The studies revealed that the quantity of mosquitocidal toxins produced from CHW is at par with NYSM. The bacteria produced in these media, were bioassayed against mosquito vectors (Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti) and it was found that the toxic effect was statistically comparable. Cost-effective analysis have revealed that, production of biopesticides from CHW is highly economical. Therefore, the utilization of CHW provides dual benefits of effective utilization of environmental waste and efficient production of mosquitocidal toxins.

  7. Energy Efficient Dryer with Rice Husk Fuel for Agriculture Drying

    Directory of Open Access Journals (Sweden)

    M. Djaeni

    2015-02-01

    Full Text Available Energy usage is crucial aspect on agriculture drying process. This step spends about 70% of total energy in post harvest treatment. The design of efficient dryer with renewable energy source is urgently required due to the limitation of fossil fuel energy. This work discusses the performance of air dehumidification using rice husk fuel as heat source for onion, and paddy drying. Unlike conventional dryer, the humidity of air during the drying was dehumidified by adsorbent. Hence, the driving force of drying can be  kept high.  As consequences, the drying time and energy usage can be reduced. Here, the research was conducted in two step: laboratory and pilot scale tests. Results showed that the lowering air humidity with rice husk fuel has improved the energy efficiency. At operational temperature 60oC, the heat efficiency of 75%  was achieved. 

  8. Peanut Husk Filled Polyethylene Composites: Effects of Filler Content and Compatibilizer on Properties

    Directory of Open Access Journals (Sweden)

    Henry C. Obasi

    2015-01-01

    Full Text Available Agrowaste biocomposites were obtained using peanut husk filler and LDPE. The effects of agrofiller content and compatibilizer on the mechanical and biodegradable properties of the composites have been discussed. Mechanical and biodegradable behaviour of LDPE became noticeably worse when it was blended with agrofiller, due to poor compatibility between the two phases. The presence of MAPE in the composites and its compatibility with the agrofiller, led to much better dispersion and homogeneity of agrofiller in the matrix and consequently to improved properties. Water absorption and thickness swelling indices increased with increasing filler content and were reduced on addition of MAPE. Furthermore, weight loss of composites via enzymatic degradation showed that both composites were biodegradable even at high levels of filler addition. However, composites with MAPE exhibited lower weight loss.

  9. Mucoadhesivity Characterization of Isabgol Husk Mucilage Microspheres Crosslinked by Glutaraldehyde.

    Science.gov (United States)

    Sharma, Vipin Kumar; Sharma, Prince Prashant; Mazumder, Bhasker; Bhatnagar, Aseem; Singh, Thakuri

    2015-01-01

    The microspheres of Isabgol husk were prepared by emulsification-crosslinking technique and the gastrointestinal transition behavior of the formulation was studied by gamma scintigraphy. The impact of different process variables such as amount of glutaraldehyde, concentration of Isabgol husk and temperature was studied on surface morphology and mucoadhesion. In vitro mucoadhesive testing of formulations was performed by determination of zeta potential, mucus glycoprotein assay and mucus adsorption isotherms. The effect of feeding on retention of microspheres in the gastrointestinal track (GIT) was studied in albino rabbits by gamma scintigraphy study. The results indicated the formation of microspheres as observed by scanning electron microscopy. The smooth and round surfaces of microspheres were obtained on increasing Isabgol husk and glutaraldehyde amount. The positive zeta potential of all formulations indicated the electrostatic interaction as a mechanism of mucoadhesion between the mucus of GIT membranes and the microspheres surfaces. The influence of electrostatic interaction on mucoadhesion of microspheres was again ascertained when the mucin equilibrium adsorption on preparations indicated well fitness in Langmuir and Freundlich adsorption isotherms. During gamma scintigraphy, the stability of (99m)Tc-sodium pertechnetate was found 98.82% at pH 6.8 and 96.78% at pH 7.2, respectively. It indicated the minimal leaching of bound radionuclide from microspheres during gastrointestinal transition as observed in gamma scintigraphic images of the rabbits. The microspheres retained in GIT even after 24 hrs of oral administration. The results indicated the applicability of Isabgol husk mucilage in the development of mucoadhesive microspheres.

  10. Importance of husk covering on field infestation of maize by ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... An experiment was conducted to determine the importance of husk covering on field infestation of maize by the maize weevil, Sitophilus zeamais, at Bako, western Ethiopia. Five maize genotypes, G1. (SZSYNA99- F2 -33-4-2 X SC22), G2 (CML-197 X SZSYNA99- F2 -33-4-1), G3 (SZSYNA99-F2 -79-4-3 X ...

  11. Silica from Ash

    Indian Academy of Sciences (India)

    Chemical. Tech.) ... waste disposal but also recovers a valuable silica product, together with certain useful associate recoveries. ... (consisting of residue digested ash, sodium-silicate, water and free sodium hydroxide). In the second step of the ...

  12. Use of rice husk in waste cooking oil pretreatment.

    Science.gov (United States)

    Schneider, Lara Talita; Bonassa, Gabriela; José Alves, Helton; Weiser Meier, Thompson Ricardo; Frigo, Elisandro Pires; Teleken, Joel Gustavo

    2017-11-10

    Since industrial wastes are increasing, the development of studies to find ways for their use is urgent. Waste cooking oil is an important source for the production of biodiesel, one of the main biofuels in Brazil. However, during cooking, the oil undergoes conditions that change its properties and decrease its quality, such as its acidity value. Current research treats waste cooking oil by the adsorption process using rice husk, an agro-industrial waste, and activated carbon to compare results. The potential of the adsorbents to remove free fatty acids in waste cooking oil has been investigated by the batch technique, evaluating different operating conditions of temperature, adsorbent mass and agitation. Adsorbents were characterized by nitrogen physisorption, scanning electron microscope, energy-dispersive spectroscopy and X-ray diffraction. The maximum result obtained for activated carbon at acidity reduction was 63%, using 22.4°C, 169.64 rpm and 3.39 g of adsorbent mass. Already, using the rice husk the percentage of removal was the same, 63% using 22.4°C, 80.36 rpm and 1.61 g of adsorbent, however in shorter times. The results prove that the application of the rice husk for this purpose is advantageous, for being a low-cost material, available on a large scale and that provide results similar to activated carbon.

  13. Sorption of Lead (II Ions on Activated Coconut Husk

    Directory of Open Access Journals (Sweden)

    Amin Jahangard

    2016-10-01

    Full Text Available Background: In recent years, various toxic chemicals/compounds have been widely detected at dangerous levels in drinking water in many parts of the world posing a variety of serious health risks to human beings. One of these toxic chemicals is lead, so this paper aimed to evaluate of efficiency coconut husk as cheap adsorbent for removal lead under different conditions. Methods: In the spring of 2015, batch studies were performed in laboratory (Branch of Hamadan, Islamic Azad University, to evaluate the influences of various experimental parameters like pH, initial concentration, adsorbent dosage, contact time and the effect of temperature on the adsorption capacity of coconut husk for removal lead from aqueous solution. Results: Optimum conditions for Pb (II removal were pH 6, adsorbent dosage 1g/100ml of solution and equilibrium time 120 min. The adsorption isotherm was also affected by temperature since the adsorption capacity was increased by raising the temperature from 25 to 45 °C. The equilibrium adsorption isotherm was better described by Freuindlich adsorption isotherm model. Conclusion: It is evident from the literature survey that coconut-based biosorbents have shown good potential for the removal of various aquatic pollutants. Coconut husk-based activated carbon can be a promising adsorbent for removal of Pb from aqueous solutions.

  14. Thermal treatment of ashes[Fly Ash from Municipal Waste Incineration]; Termisk rening av askor

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, Karin; Berg, Magnus; Bjurstroem, Henrik [AaF-Energi och Miljoe AB, Stockholm (Sweden); Nordin, Anders [Umeaa Univ. (Sweden). Dept. of Applied Physics and Electronics

    2003-04-01

    In this project descriptions of different processes for thermal treatment of ashes have been compiled. A technical and economic evaluation of the processes has been done to identify possibilities and problems. The focus in the project lays on treatment of fly ash from municipal waste incineration but the processes can also be used to treat other ashes. When the ash is heated in the thermal treatment reactor, with or without additives, the material is sintered or vitrified and at the same time volatile substances (Zn, Pb, Cd, Hg etc.) are separated. In general the separation is more effective in processes with reducing conditions compared to oxidizing conditions. Oxidizing processes have both worse separation capacity and require more energy. The oxidizing processes are mainly used to stabilize the ash through vitrification and they are in some cases developed for management of municipal sewage sludge and bottom ash. However, these processes are often not as complex as for example an electric arc melting furnace with reducing conditions. The research today aim to develop more effective electrical melting systems with reducing conditions such as plasma melting furnaces, electric resistance melting furnaces and low frequency induction furnaces. A central question in the evaluation of different thermal treatment processes for ash is how the residues from the treatment can be used. It is not certain that the vitrified material is stable enough to get a high economic value, but it can probably be used as construction material. How the remaining metals in the ash are bound is very important in a long-time perspective. Further studies with leaching tests are necessary to clarify this issue. The heavy metal concentrate from the processes contains impurities, such as chlorine, which makes it unprofitable to obtain the metals. Instead the heavy metal concentrate has to be land filled. However, the amount of material for land filling will be much smaller if only the heavy

  15. Stabilization of expansive soil using bagasse ash & lime | Wubshet ...

    African Journals Online (AJOL)

    7-5 soil on the AASHTO classification was stabilized using 3% lime, 15% bagasse ash and 15% bagasse ash in combination with 3% lime by dry weight of the soil. The effect of the additives on the soil was investigated with respect to plastcity, ...

  16. 76 FR 78231 - Notice of Decision To Authorize the Importation of Fresh Cape Gooseberry Fruit With Husks From Chile

    Science.gov (United States)

    2011-12-16

    ... Gooseberry Fruit With Husks From Chile AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION... continental United States of fresh Cape gooseberry fruit (Physalis peruviana L.) with husks from Chile. Based... fresh Cape gooseberry fruit (Physalis peruviana L.) with husks from Chile. We solicited comments on the...

  17. Alternative treatments to improve the potential of rice husk as adsorbent for methylene blue.

    Science.gov (United States)

    Franco, Dison S P; Tanabe, Eduardo H; Bertuol, Daniel A; Dos Reis, Glaydson S; Lima, Éder C; Dotto, Guilherme L

    2017-01-01

    Alternative treatments, such as, NaOH, ultrasound assisted (UA) and supercritical CO2 (SCO2), were performed to improve the potential of rice husk as adsorbent to remove methylene blue (MB) from aqueous media. All the treatments improved the surface characteristics of rice husk, exposing its organic fraction and/or providing more adsorption sites. The Langmuir and Hill models were able to explain the MB adsorption for all adsorbents in all studied temperatures. The experimental and modeled parameters demonstrated that the MB adsorption was favored by the temperature increase and by the use of NaOH-rice husk. The maximum adsorption capacities for the MB solutions (ranging from 10 to 100 mg L-1), estimated from the Langmuir model at 328 K, were in the following order: NaOH rice-husk (65.0 mg g-1) > UA-rice husk (58.7 mg g-1) > SCO2-rice husk (56.4 mg g-1) > raw rice husk (52.2 mg g-1). The adsorption was a spontaneous, favorable and endothermic process. In general, this work demonstrated that NaOH, UA and SCO2 treatments are alternatives to improve the potential of rice husk as adsorbent.

  18. Alkaline peroxide assisted wet air oxidation pretreatment approach to enhance enzymatic convertibility of rice husk.

    Science.gov (United States)

    Banerjee, Saumita; Sen, Ramkrishna; Mudliar, Sandeep; Pandey, R A; Chakrabarti, Tapan; Satpute, Dewanand

    2011-01-01

    Pretreatment of rice husk by alkaline peroxide assisted wet air oxidation (APAWAO) approach was investigated with the aim to enhance the enzymatic convertibility of cellulose in pretreated rice husk. Rice husk was presoaked overnight in 1% (w/v) H(2)O(2) solution (pH adjusted to 11.5 using NaOH) (equivalent to 16.67 g H(2)O(2) and 3.63 g NaOH per 100 g dry, untreated rice husk) at room temperature, followed by wet air oxidation (WAO). APAWAO pretreatment resulted in solubilization of 67 wt % of hemicellulose and 88 wt % of lignin initially present in raw rice husk. Some amount of oligomeric glucose (˜8.3 g/L) was also observed in the APAWAO liquid fraction. APAWAO pretreatment resulted in 13-fold increase in the amount of glucose that could be obtained from otherwise untreated rice husk. Up to 86 wt % of cellulose in the pretreated rice husk (solid fraction) could be converted into glucose within 24 hours, yielding over 21 g glucose per 100 g original rice husk. Scanning electron microscopy was performed to visualize changes in biomass structure following the APAWAO pretreatment. Enzymatic cellulose convertibility of the pretreated slurry at high dry matter loadings was also investigated. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  19. Evaluation of Kola-Pod Husk Meal in Broiler Finisher Diets ...

    African Journals Online (AJOL)

    Nigeria is the world's largest producer of kola nut. The pod husk, which constitutes over 50% of the kola fruit, has been a farm waste to date. Its crude protein content which is similar to that of maize suggests that it is possible to partially replace maize with pod husk meal (KPHM) in broiler finisher diets. In this study, KPHM ...

  20. Genome-wide association study (GWAS) reveals the genetic architecture of four husk traits in maize.

    Science.gov (United States)

    Cui, Zhenhai; Luo, Jinhong; Qi, Chuangye; Ruan, Yanye; Li, Jing; Zhang, Ao; Yang, Xiaohong; He, Yan

    2016-11-21

    Maize (Zea mays) husk referring to the leafy outer enclosing the ear, plays an important role in grain production by directly contributing photosynthate and protecting ear from pathogen infection. Although the physiological functions related to husk have been extensively studied, little is known about its morphological variation and genetic basis in natural population. Here we utilized a maize association panel including 508 inbred lines with tropical, subtropical and temperate backgrounds to decipher the genetic architecture attributed to four husk traits, i.e. number of layers, length, width and thickness. Evaluating the phenotypic diversity at two different environments showed that four traits exhibit broadly natural variations and moderate levels of heritability with 0.64, 0.74, 0.49 and 0.75 for number, length, width and thickness, respectively. Diversity analysis indicated that different traits have dissimilar responses to subpopulation effects. A series of significantly positive or negative correlations between husk phenotypes and other agronomic traits were identified, indicating that husk growth is coordinated with other developmental processes. Combining husk traits with about half of a million of single nucleotide polymorphisms (SNPs) via genome-wide association study revealed a total of 9 variants significantly associated with traits at P husk development, and further studies on identified candidate genes facilitate to illuminate molecular pathways regulating maize husk growth.

  1. Design and modeling of a novel continuous open core downdraft rice husk gasifier

    NARCIS (Netherlands)

    Manurung, Robert

    1994-01-01

    Rice husk is one of the most widely available agricultural wastes in many rice producing countries around the world. Conversion of the abundant supply of rice husk into clean energy is an opportunity to expand the energy resource base while reducing the environmental burden now associated with the

  2. Effect of Rice-Husk Filler on Some Mechanical and End-Use ...

    African Journals Online (AJOL)

    The effect of adding varying amount of rice-husk powder on the mechanical properties of low density polyethylene in the absence coupling agent was investigated using ASTM D5323 test method. Composites of low density polyethylene and rice-husk powder (viz 1 to 7 % wt) were prepared using single extruder fitted with a ...

  3. Frictional and heat resistance characteristics of coconut husk particle filled automotive brake pad

    Science.gov (United States)

    Bahari, Shahril Anuar; Chik, Mohd Syahrizul; Kassim, Masitah Abu; Som Said, Che Mohamad; Misnon, Mohd Iqbal; Mohamed, Zulkifli; Othman, Eliasidi Abu

    2012-06-01

    The objective of this study was to determine the friction and heat resistance characteristics of automotive brake pad composed with different sizes and percentages of coconut husk particle. The materials used were phenolic resin (phenol formaldehyde) as binder, copper, graphite and brass as friction producer/modifiers, magnesium oxide as abrasive material, steel and barium sulfate as reinforcement while coconut husk particle as filler. To obtain particle, the coconut husk was ground and dried to 3% moisture content. Then the coconut husk particle was screened using 80 mesh (to obtain coarse dust) and 100 mesh (to obtain fine dust). Different percentages of particle, such as 10 and 30% were used in the mixture of brake pad materials. Then the mixture was hot-pressed to produce brake pad. Chase machine was used to determine the friction coefficient in friction resistance testing, while thermogravimetric analyzer (TGA) machine was used to determine the heat decomposition values in heat resistance testing. Results showed that brake pad with 100 mesh and 10% composition of coconut husk particle showed the highest friction coefficient. For heat resistance, brake pad with 100 mesh and 30% composition of coconut husk dust showed the highest decomposition temperature, due to the high percentage of coconut husk particle in the composition, thus increased the thermal stability. As a comparison, brake pad composed with coconut husk particle showed better heat resistance results than commercial brake pad.

  4. Rice Husk as Filler in the Production of Bricks Using Gboko Clay ...

    African Journals Online (AJOL)

    Farmers and rice millers normally burn the rice husk (RH)as fuel in milling which leads to air pollution. This study looked at ways of converting the husk into materials for the construction industry. Chemical composition of RH and Gboko clay soil were investigated using X-ray diffraction test. Four grades (75, 150, 300, 425 ...

  5. Partial Placement of Maize with Cocoa Husks Meals in Layers Mash ...

    African Journals Online (AJOL)

    The partial replacement value of cocoa husk meals for maize in laying hen diets were assessed under an on-farm condition, Urea-treated and untreated cocoa husk meals were each incorporated into the farmer's layer mash (FLM) to replace 25% of the maize portion. FLM contained 40% maize. Six groups of 15 laying hens ...

  6. effect of replacing cocoa husk for wheat bran on internal organs ...

    African Journals Online (AJOL)

    EFFECT OF REPLACING COCOA HUSK FOR WHEAT BRAN ON INTERNAL ORGANS, CARCASS YIELD, SERUM METABOLITE AND ECONOMICS OF PRODUCTION OF GROWING COCKERELS. ... Creatinine concentrations were lower on all the cocoa husk diets compared with the control. Wheat bran can be replaced ...

  7. Biodiesel production from waste cooking oil using a heterogeneous catalyst from pyrolyzed rice husk.

    Science.gov (United States)

    Li, Ming; Zheng, Yan; Chen, Yixin; Zhu, Xifeng

    2014-02-01

    A solid acid catalyst was prepared by sulfonating pyrolyzed rice husk with concentrated sulfuric acid, and the physical and chemical properties of the catalyst were characterized in detail. The catalyst was then used to simultaneously catalyze esterification and transesterification to produce biodiesel from waste cooking oil (WCO). In the presence of the as-prepared catalyst, the free fatty acid (FFA) conversion reached 98.17% after 3h, and the fatty acid methyl ester (FAME) yield reached 87.57% after 15 h. By contrast, the typical solid acid catalyst Amberlyst-15 obtained only 95.25% and 45.17% FFA conversion and FAME yield, respectively. Thus, the prepared catalyst had a high catalytic activity for simultaneous esterification and transesterification. In addition, the catalyst had excellent stability, thereby having potential use as a heterogeneous catalyst for biodiesel production from WCO with a high FFA content. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Application of Fly Ash from Solid Fuel Combustion in Concrete

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard

    2008-01-01

    Application of Fly Ash from Solid Fuel Combustion in Concrete Kim H. Pedersen Abstract Industrial utilization of fly ash from pulverized coal combustion plays an important role in environmentally clean and cost effective power generation. Today, the primary market for fly ash utilization is as po......Application of Fly Ash from Solid Fuel Combustion in Concrete Kim H. Pedersen Abstract Industrial utilization of fly ash from pulverized coal combustion plays an important role in environmentally clean and cost effective power generation. Today, the primary market for fly ash utilization...... is as pozzolanic additive in the production of concrete. However, the residual carbon in fly ash can adsorb the air entraining admixtures (AEAs) added to enhance air entrainment in concrete in order to increase its workability and resistance toward freezing and thawing conditions. The problem has increased...... Nordjyllandsværket, unit 3; 3) post treatment of fly ash to lower its AEA adsorptivity. The foam index test is the method usually employed to determine the degree of fly ash interference with AEAs in concrete. The test involves the use of commercial AEAs and visual observation of foam stability. These facts reduce...

  9. Rice husk-originating silicon-graphite composites for advanced lithium ion battery anodes

    Science.gov (United States)

    Kim, Hye Jin; Choi, Jin Hyeok; Choi, Jang Wook

    2017-09-01

    Rice husk is produced in a massive amount worldwide as a byproduct of rice cultivation. Rice husk contains approximately 20 wt% of mesoporous SiO2. We produce mesoporous silicon (Si) by reducing the rice husk-originating SiO2 using a magnesio-milling process. Taking advantage of meso-porosity and large available quantity, we apply rice husk-originating Si to lithium ion battery anodes in a composite form with commercial graphite. By varying the mass ratio between these two components, trade-off relation between specific capacity and cycle life was observed. A controllable pre-lithiation scheme was adopted to increase the initial Coulombic efficiency and energy density. The series of electrochemical results suggest that rice husk-originating Si-graphite composites are promising candidates for high capacity lithium ion battery anodes, with the prominent advantages in battery performance and scalability.

  10. Integrated management of ash from industrial and domestic combustion: a new sustainable approach for reducing greenhouse gas emissions from energy conversion.

    Science.gov (United States)

    Benassi, Laura; Dalipi, Rogerta; Consigli, Veronica; Pasquali, Michela; Borgese, Laura; Depero, Laura E; Clegg, Francis; Bingham, Paul A; Bontempi, Elza

    2017-06-01

    This work supports, for the first time, the integrated management of waste materials arising from industrial processes (fly ash from municipal solid waste incineration and coal fly ash), agriculture (rice husk ash), and domestic activities (ash from wood biomass burning in domestic stoves). The main novelty of the paper is the reuse of wood pellet ash, an underestimated environmental problem, by the application of a new technology (COSMOS-RICE) that already involves the reuse of fly ashes from industrial and agricultural origins. The reaction mechanism involves carbonation: this occurs at room temperature and promotes permanent carbon dioxide sequestration. The obtained samples were characterized using XRD and TGA (coupled with mass spectroscopy). This allowed quantification of the mass loss attributed to different calcium carbonate phases. In particular, samples stabilized using wood pellet ash show a weight loss, attributed to the decomposition of carbonates greater than 20%. In view of these results, it is possible to conclude that there are several environmental benefits from wood pellet ash reuse in this way. In particular, using this technology, it is shown that for wood pellet biomass the carbon dioxide conversion can be considered negative.

  11. Effect of addition of arc furnace dust in the microstructural properties of fly ash alkali-activated; Estudo do efeito da adicao do po de aciaria nas propriedades microestruturais de matrizes a base de cinzas volantes alcali-ativadas

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, Alexandre Silva de [Centro de Estudos Superiores Feevale, Novo Hamburgo, RS (Brazil); Pavao, Bruno Barreto; Masuero, Angela Boreges; Dal Molin, Denise Carpena Coitinho; Vilela, Antonio Cezar Faria [Universidade Federal do Rio Grande do Sul (UFRS), RS (Brazil)

    2010-07-01

    The search for alternative materials for construction, with less environmental impact, has been the subject of several studies. The alkali-activated cements have shown potential for the reuse of waste, and can be used in the technology of solidification/stabilization. Thus, this study aims to evaluate the main effect of adding arc furnace dust (AFD) in the microstructural properties of matrices based on fly ash alkali-activated. Three levels of AFD were studied: 0, 5, 15 and 25%. The curing was set at 70°C/24 h, and after, kept at room temperature until the age of analysis - 1, 28 and 180 days, with XRD and FTIR analysis. In the XRD spectres it was found that compounds of albite and natron decrease the intensity of their peaks in that there is an increase in the levels of AFD. Concerning to the FTIR, we observed that the band characteristic of the fly ash (FA) 1084 cm{sup -1} was shifted to bands near 1000 cm{sup -1}, which shows that the residue does not interfere in the polymerization and aluminosilicate gel formation. Therefore, under the microstructural aspect, there were no major changes that would impair the use of this residue in alkali-activated matrices. (author)

  12. Biosorption of zinc from aqueous solution using chemically treated rice husk.

    Science.gov (United States)

    Zhang, Ying; Zheng, Ru; Zhao, Jiaying; Zhang, Yingchao; Wong, Po-Keung; Ma, Fang

    2013-01-01

    In this study, adsorption of zinc onto the adsorbent (untreated rice husk and NaOH-treated rice husk) was examined. During the removal process, batch technique was used, and the effects of pH and contact time were investigated. Langmuir isotherm was applied in order to determine the efficiency of NaOH-treated rice husk used as an adsorbent. The zinc adsorption was fast, and equilibrium was attained within 30 min. The maximum removal ratios of zinc for untreated rice husk and NaOH-treated rice husk after 1.5 h were 52.3% and 95.2%, respectively, with initial zinc concentration of 25 mg/L and optimum pH of 4.0. Data obtained from batch adsorption experiments fitted well with the Langmuir isotherm model. Maximum adsorption capacity of zinc onto untreated rice husk and NaOH-treated rice husk was 12.41 mg/g, and 20.08 mg/g respectively, at adsorbent dosage of 1 g/L at 25°C. The nature of functional groups (i.e., amino, carboxyl, and hydroxyl) and metal ion interactions was examined by the FT-IR technique. It was concluded that the NaOH-treated rice husk had stronger adsorption capacity for Zn(2+) compared with the untreated rice husk. The NaOH-treated rice husk is an inexpensive and environmentally friendly adsorbent for Zn(2+) removal from aqueous solutions.

  13. Identification and Fine Mapping of a White Husk Gene in Barley (Hordeum vulgare L.).

    Science.gov (United States)

    Hua, Wei; Zhang, Xiao-Qi; Zhu, Jinghuan; Shang, Yi; Wang, Junmei; Jia, Qiaojun; Zhang, Qisen; Yang, Jianming; Li, Chengdao

    2016-01-01

    Barley is the only crop in the Poaceae family with adhering husks at maturity. The color of husk at barely development stage could influence the agronomic traits and malting qualities of grains. A barley mutant with a white husk was discovered from the malting barley cultivar Supi 3 and designated wh (white husk). Morphological changes and the genetics of white husk barley were investigated. Husks of the mutant were white at the heading and flowering stages but yellowed at maturity. The diastatic power and α-amino nitrogen contents also significantly increased in wh mutant. Transmission electron microscopy examination showed abnormal chloroplast development in the mutant. Genetic analysis of F2 and BC1F1 populations developed from a cross of wh and Yangnongpi 5 (green husk) showed that the white husk was controlled by a single recessive gene (wh). The wh gene was initially mapped between 49.64 and 51.77 cM on chromosome 3H, which is syntenic with rice chromosome 1 where a white husk gene wlp1 has been isolated. The barley orthologous gene of wlp1 was sequenced from both parents and a 688 bp deletion identified in the wh mutant. We further fine-mapped the wh gene between SSR markers Bmac0067 and Bmag0508a with distances of 0.36 cM and 0.27 cM in an F2 population with 1115 individuals of white husk. However, the wlp1 orthologous gene was mapped outside the interval. New candidate genes were identified based on the barley genome sequence.

  14. Emerald ash borer aftermath forests: the future of ash ecosystems

    Science.gov (United States)

    Kathleen S. Knight; Daniel A. Herms; John Cardina; Robert Long; Kamal J.K. Gandhi; Catharine P. Herms

    2011-01-01

    The effects of emerald ash borer (EAB) (Agrilus planipennis) on forest ecosystems are being studied through a collaborative research program between the U.S. Forest Service and The Ohio State University. We are monitoring ash demographics, understory light availability, EAB population dynamics, native and non-native plants, and effects of ash...

  15. Photoreduction of mercury metal (Hg) using catalyst of oxalic acid from cellulose of rice husks (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Sumiardi, Ade, E-mail: zulfasalmasaodah@gmail.com [Departement of Biology, Faculty of Sciences and Pharmacy, Math’laul Anwar University, Banten (Indonesia); Novi, Cory; Sukaesih, Esih [Departement of Chemistry, Faculty of Sciences and Pharmacy, Math’laul Anwar University, Banten (Indonesia); Humaedi, Aji [Departement of Pharmacy, Faculty of Sciences and Pharmacy, Math’laul Anwar University, Banten (Indonesia)

    2016-04-19

    Photoreduction of mercury metal using catalyst of oxalic acid from cellulose of rice husks (Oryza sativa L.) is one of methods to reduce toxicity properties of the mercury metal in the society. The purpose of this research is to enhance photoreduction of mercury metal using catalyst of oxalic acid from cellulose of rice husks (Oryza sativa L.) at various concentrations. Photoreduction process is carried out in a closed reactor equipped with UV light and magnetic stirrer. Analysis of the influence of oxalic acid is determined by adding 25 mL of Hg (II) 5 ppm without oxalic acid, 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 3 ppm, 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 6 ppm, 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 9 ppm, 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 12 ppm and 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 15 ppm. All treatments are followed by centrifugation for 15 minutes, then the concentration of Hg residual in the solution is measured by mercury analyzer. The research results showed that addition of oxalic acid concentration from the cellulose of rice husks (Oryza sativa L.) can enhance photoreduction of mercury metal. Optimum concentration reduction of mercury metal with addition of oxalic acid is obtained as many as 9-12 ppm. It can reduce the concentration of mercury metal (II) by 68.8% to 88.6%.

  16. Hygroscopic properties of volcanic ash

    National Research Council Canada - National Science Library

    T. L. Lathem; P. Kumar; A. Nenes; J. Dufek; I. N. Sokolik; M. Trail; A. Russell

    2011-01-01

      Volcanic ash is hygroscopic Water vapor adsorption is the main proceess controlling ash hygroscopicity The results can be parameterized in a simple correlation for use in models Limited observational...

  17. Rising from the ashes

    Energy Technology Data Exchange (ETDEWEB)

    Short, G. [RockTron Advanced Products (United States)

    2010-05-15

    The paper describes a new process for recovering useful minerals from the world's stockpile of waste fly ash. The technology from RockTron allows separation and recycling of minerals from fly ash so they can be used again in the rubber, plastics and coatings industries. Cenospheres, carbon, magnetite and finally alumino-silicates can be recovered. The first recycling plant in the UK has been built at Fiddler's Ferry power station in Widnes and another plant is being built at Gale Common. 2 photos.

  18. Nanostructured silicon nitride from wheat and rice husks

    Energy Technology Data Exchange (ETDEWEB)

    Qadri, S. B.; Rath, B. B.; Gorzkowski, E. P.; Wollmershauser, J. A.; Feng, C. R. [Materials Science and Component Technology Directorate, Naval Research Laboratory, Washington, D.C. 20375 (United States)

    2016-04-07

    Nanoparticles, submicron-diameter tubes, and rods of Si{sub 3}N{sub 4} were synthesized from the thermal treatment of wheat and rice husks at temperatures at and above 1300 °C in a nitrogen atmosphere. The whole pattern Rietveld analysis of the observed diffraction data from treatments at 1300 °C showed the formation of only hexagonal α-phase of Si{sub 3}N{sub 4} with an R-factor of 1%, whereas samples treated at 1400 °C and above showed both α- and β-phases with an R-factor of 2%. Transmission electron microscopy showed the presence of tubes, rods, and nanoparticles of Si{sub 3}N{sub 4}. In a two-step process, where pure SiC was produced first from rice or wheat husk in an argon atmosphere and subsequently treated in a nitrogen atmosphere at 1450 °C, a nanostructured composite material having α- and β-phases of Si{sub 3}N{sub 4} combined with cubic phase of SiC was formed. The thermodynamics of the formation of silicon nitride is discussed in terms of the solid state reaction between organic matter (silica content), which is inherently present in the wheat and rice husks, with the nitrogen from the furnace atmosphere. Nanostructures of silicon nitride formed by a single direct reaction or their composites with SiC formed in a two-step process of agricultural byproducts provide an uncomplicated sustainable synthesis route for silicon nitride used in mechanical, biotechnology, and electro-optic nanotechnology applications.

  19. Glass-ceramic from mixtures of bottom ash and fly ash.

    Science.gov (United States)

    Vu, Dinh Hieu; Wang, Kuen-Sheng; Chen, Jung-Hsing; Nam, Bui Xuan; Bac, Bui Hoang

    2012-12-01

    Along with the gradually increasing yield of the residues, appropriate management and treatment of the residues have become an urgent environmental protection problem. This work investigated the preparation of a glass-ceramic from a mixture of bottom ash and fly ash by petrurgic method. The nucleation and crystallization kinetics of the new glass-ceramic can be obtained by melting the mixture of 80% bottom ash and 20% fly ash at 950 °C, which was then cooled in the furnace for 1h. Major minerals forming in the glass-ceramics mainly are gehlenite (Ca(2)Al(2)SiO(7)) & akermanite (Ca(2)MgSiO(7)) and wollastonite (CaSiO(3)). In addition, regarding chemical/mechanical properties, the chemical resistance showing durability, and the leaching concentration of heavy metals confirmed the possibility of engineering and construction applications of the most superior glass-ceramic product. Finally, petrurgic method of a mixture of bottom ash and fly ash at 950 °C represents a simple, inexpensive, and energy saving method compared with the conventional heat treatment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Water permeabilities of pulverized fuel ash; Bifuntan sekitanbai no tosui tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, T. [Center for Coal Utilization, Japan, Tokyo (Japan); Nagataki, S. [Niigata University, Niigata (Japan); Hosoda, N. [Kumagai Gumi Co. Ltd., Tokyo (Japan); Utsuki, T. [The Coal Mining Research Center, Japan, Tokyo (Japan); Kubo, H. [Obayashi Corp., Tokyo (Japan)

    1996-09-01

    It is intended to establish a technology to utilize coal ash in bulk to deal with its increasing production. In order to expand its use into earth engineering materials, two kinds of combustion ashes produced from dust coal burning power plants were used for studies using different kinds of tests. The tests were carried out on strength properties, water permeability, and characteristics of dissolving trace amounts of chemical constituents, with regard to addition effects of cement into compacted and slurry-state dust coal burned ashes. The derived findings may be summarized as follows: as the strength properties, the strength for both of the compacted and slurry-state ashes increases as the cement addition ratio is increased; growth of the strength due to the cement addition ratio and material age varies depending on the kinds of dust coal burned ash; comparison of strengths of the compacted and the slurry-state ashes indicates the strength of the latter ash is about one-third to quarter of that of the former ash; water permeability of the ashes decreases both in the compacted and slurry- state ashes as the cement addition ratio is increased; and the cement addition ratio gives greater impact to the water permeability than the density of the ashes. 28 figs., 5 tabs.

  1. Sodium ion interaction with psyllium husk (Plantago sp.)

    OpenAIRE

    Jimoh, M.A.; MacNaughtan, W.; Williams, H.E.L.; Greetham, D.; Linforth, R.L.; Fisk, Ian D.

    2016-01-01

    The nature of and factors effecting sodium interactions with psyllium were investigated in vitro. In a batch extraction system, psyllium mucilage gel retained at least 50% of sodium across a range of concentrations (5–300 mg sodium per g psyllium) and pH (2–10) environments. FTIR and Na NMR analyses of psyllium gels indicated that binding was complex with non-specific multi-site interactions. The potential use of psyllium husk as a binding agent for the reduction of bioavailable sodium was th...

  2. Use of municipal solid waste incineration bottom ash and crop by-product for producing lightweight aggregate

    Science.gov (United States)

    Giro-Paloma, J.; Ribas-Manero, V.; Maldonado-Alameda, A.; Formosa, J.; Chimenos, J. M.

    2017-10-01

    Due to the growing amount of residues in Europe, it is mandatory to provide a viable alternative for managing wastes contributing to the efficient use of resources. Besides, it is also essential to move towards a low carbon economy, priority EU by 2050. Among these, it is important to highlight the development of sustainable alternatives capable of incorporating different kind of wastes in their formulations.Municipal Solid Waste Incineration (MSWI) is estimated to increase in Europe, where the accessibility of landfill is restricted. Bottom ash (BA) is the most significant by-product from MSWI as it accounts for 85 - 95 % of the solid product resulting from combustion. BA is a mixture of calcium-rich compounds and others silicates enriched in iron and sodium. In addition, it is categorized as non-hazardous waste which can be revalorized as secondary material in construction or civil engineering fields, previous weathering stabilization during 2 - 3 months. Taking into account the relative proportion of each size fraction and the corresponding material characterization, the content of glass (primary and secondary) is estimated to be around 60 wt%. Furthermore, as a renewable resource and according to waste management European policies, residual agricultural biomass has attracted attention in preparation of advanced materials for various applications, due to their low cost, abundance, and environment friendliness. Among this residual biomass, rice husk is a by-product of rice milling industry which has high content of silica and has been widely used in buildings as natural thermal insulation material.Weathered BA (WBA) with a particle size less than 30 mm was milled under 100 μm, mixed with 2.0 - 5.0 mm rice husk, formed into ball-shaped pellets and sintered by different thermal treatments, which remove the organic matter content generating a large porosity. Physico-chemical analysis and mechanical behavior of the manufactured lightweight aggregates were tested

  3. Ash transformation and deposition behavior during co-firing biomass with sewage sludge

    DEFF Research Database (Denmark)

    Wang, Liang; Wu, Hao; Jensen, Peter Arendt

    In the present work, the ash transformation and deposition behavior during wheat straw and wood waste combustion were investigated by combustion experiments in an entrained flow reactor. The influence of sewage sludge addition on ash chemistry and deposition tendency was also studied. During...... combustion wheat straw, fine fly ash particles smaller than 2.5 μm are mainly formed due to vaporization, nucleation and condensation of K, Cl, S and P species. Large fly ash particles consist of condensed potassium chloride crystals and molten/partial molten spherical particles rich in Ksilicates and K......-Ca-silicates. The deposits formed on a well-controlled sampling probe are dominated by molten particles rich in K silicates. Over 70% of K in the fly ash is water soluble. The fine fly ash from wood waste combustion consists of mainly KCl and NaCl. Both ash clusters and molten spherical particles are found from the ash...

  4. Cocos nucifera Linn. (Palmae) husk fiber ethanolic extract: antioxidant capacity and electrochemical investigation.

    Science.gov (United States)

    Oliveira, Monika Bezerra dos Santos; Valentim, Iara Barros; de Vasconcelos, Camila Calado; Omena, Cristhiane Maria Bazílio; Bechara, Etelvino José Henriques; da Costa, João Gomes; Freitas, Mikael de Lima; Sant'Ana, Antônio Euzébio Goulart; Goulart, Marília Oliveira Fonseca

    2013-02-01

    The present study aims to determine the antioxidant capacity of the ethanolic extracts of husk fiber of four coconut (Cocos nucifera L.) varieties (yellow dwarf, green dwarf, giant and hybrid) and to evaluate the electrochemical behavior of these extracts on a glassy carbon electrode and on a modified glassy carbon electrode. The highest values of total phenolic content were obtained for the hybrid (531 ± 24 mg GAE g(-1) dry extract) and yellow dwarf (501 ± 29 mg GAE g(-1) dry extract) varieties and the lowest was for the green dwarf variety with 58 ± 9 mg GAE g(-1) dry extract. The ability of the extracts to scavenge DPPH˙ radicals was in the order of giant > yellow dwarf > hybrid > green dwarf and the IC50 values varied from 8.6 to 55.9 μg mL(-1). All varieties showed reducing potential by the use of FRAP and CUPRAC methods, with the lowest performance obtained for the green dwarf variety. Additionally, through the use of mimetic biomembranes, ethanolic extracts of coconut husk were shown to protect lipids against oxidative damage independent of the variety. The main antioxidants identified in the extract of yellow dwarf variety by UPLC-MS were quercetin and catechin. Cyclic voltammetric studies of the ethanolic extracts on glassy carbon electrode confirmed the presence of easily oxidized compounds, and the high antioxidant capacity of the varieties. This capacity was expressed as mg quercetin equivalents g(-1) dry extract and ranged from 25.9 up to 53.5 mg QE g(-1). A poly-xanthurenic acid (poly-Xa)/multi-walled carbon nanotube (MWCNT) / glassy carbon modified electrode (poly-Xa/MWCNT/GCE) was used for this purpose. Our findings suggest that these extracts are potentially important antioxidant supplements for the everyday human diet, pharmaceutical and cosmetic industries, thereby aggregating value to the enormous amount of waste from the coconut industry, mostly used for burning purposes.

  5. Fusion characterization of biomass ash

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Teng [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Sino-Danish Center for Education and Research, Beijing, 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Fan, Chuigang; Hao, Lifang [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Li, Songgeng, E-mail: sgli@ipe.ac.cn [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Song, Wenli [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Lin, Weigang [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

    2016-08-20

    Highlights: • A novel method is proposed to analyze fusion characteristics of biomass ash. • T{sub m} can represent the severe melting temperature of biomass ash. • Compared with AFT, TMA is the better choice to analyze the fusion characteristics of biomass ash. - Abstract: The ash fusion characteristics are important parameters for thermochemical utilization of biomass. In this research, a method for measuring the fusion characteristics of biomass ash by Thermo-mechanical Analyzer, TMA, is described. The typical TMA shrinking ratio curve can be divided into two stages, which are closely related to ash melting behaviors. Several characteristics temperatures based on the TMA curves are used to assess the ash fusion characteristics. A new characteristics temperature, T{sub m}, is proposed to represent the severe melting temperature of biomass ash. The fusion characteristics of six types of biomass ash have been measured by TMA. Compared with standard ash fusibility temperatures (AFT) test, TMA is more suitable for measuring the fusion characteristics of biomass ash. The glassy molten areas of the ash samples are sticky and mainly consist of K-Ca-silicates.

  6. Electrodialytic treatment of fly ash

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Pedersen, Anne Juul; Kirkelund, Gunvor Marie

    Heavy metals are removed from the fly ashes by an electrodialytic treatment with the aim of up-grading the ashes for reuse in stead of disposal in landfill.A great potential for upgrading of bio- and waste incineration ashes by electrodialytic treatment exists. In the future, the applicability...

  7. Study on Strength Behavior of Organic Soil Stabilized with Fly Ash

    Directory of Open Access Journals (Sweden)

    Bayshakhi Deb Nath

    2017-01-01

    Full Text Available The aim of this study is to investigate the effect of fly ash on the consistency, compactness, acidic properties, and strength of organic soil. The presence of organic content in the soil has detrimental impacts on the physical and strength behavior of soil. To investigate the effectiveness of fly ash in the stabilization of organic soil, two types of fly ashes (Type I and Type II at different percentages were used. It is found that fly ash significantly reduces the plasticity index of the organic soil, whereas the liquid and plastic limits increase. The dry density of the fly ash-soil mixture increases significantly, while the water requirement reduces due to the addition of fly ash. The increase of dry density compromises higher strength. The increase of qu with the increase of fly ash content is mainly due to the pozzolanic reaction of fly ash, although the reduction in water content results from the addition of dry fly ash solid. Moreover, Type I fly ash contributes a higher value of qu compared to Type II fly ash. This is attributed to the characteristics of fly ash including CaO and CaO/SiO2 ratio.

  8. Emerald Ash Borer

    Science.gov (United States)

    Deborah G. McCullough; Steven A. Katovich

    2004-01-01

    An exotic beetle from Asia was discovered in July 2002 feeding on ash (Fraxinus spp.) trees in southeastern Michigan. It was identified as Agrilus planipennis Fairmaire (Coleoptera: Buprestidae). Larvae feed in the cambium between the bark and wood, producing galleries that eventually girdle and kill branches and entire trees. Evidence suggests that A. planipennis has...

  9. Fly ash for defluoridation

    Energy Technology Data Exchange (ETDEWEB)

    Tzimou-Tsitouridou, R.

    1985-05-01

    The authors report a study of the use of a lignite fly ash to retain fluoride ions and remove them from their solutions, with a view to the use of this process for the defluoridation of water. Results are presented and the chemistry of the process is examined.

  10. Thaumasite formation in concrete and mortars containing fly ash

    Energy Technology Data Exchange (ETDEWEB)

    D.M. Mulenga; J. Stark; P. Nobst [Bauhaus-University, Weimar (Germany). F.A. Finger-Institute of Material Sciences

    2003-12-01

    Due to recent reports on deterioration of concrete structures, the thaumasite form of sulfate attack has become a subject of study and close investigation. This paper investigates the formation of thaumasite in concrete and mortars containing fly ash. The results show that thaumasite formation can occur within 84 days of exposure to sulfate solutions. High volumes of fly ash can limit or promote thaumasite formation depending on the type of cement used. Thaumasite and ettringite were found among the deterioration products. However, the thaumasite formation in the specimen prepared from sulfate resisting Portland cement was not accompanied by deterioration, except by 50% fly ash addition. The mixtures of Portland limestone cement with 40% fly ash exhibited a very limited thaumasite formation while the mixtures with 50% had no thaumasite at all. It is concluded that thaumasite can also be formed in mixtures incorporating fly ash.

  11. High quality syngas production from microwave pyrolysis of rice husk with char-supported metallic catalysts.

    Science.gov (United States)

    Zhang, Shuping; Dong, Qing; Zhang, Li; Xiong, Yuanquan

    2015-09-01

    This study aimed to obtain the maximum possible gas yield and the high quality syngas production from microwave pyrolysis of rice husk with rice husk char and rice husk char-supported metallic (Ni, Fe and Cu) catalysts. The rice husk char-supported metallic catalysts had developed pore structure and catalytic activity for gas productions and tar conversion. The temperature-rising characteristic, product yields, properties of gas products and tar conversion mechanisms were investigated. It was found that three rice husk char-supported metallic catalysts improved the microwave absorption capability and increased heating rate and final temperature. Rice husk char-supported Ni catalyst presented most effective effects on gas production, e.g. the gas yield is 53.9%, and the volume concentration of desired syngas is 69.96%. Rice husk char-supported Ni and Fe catalysts played pivotal roles in tar conversion that less heavy compounds can be detected along with the reduction of organic compound number. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Stability studies of immobilized lipase on rice husk and eggshell membrane

    Science.gov (United States)

    Abdulla, R.; Sanny, S. A.; Derman, E.

    2017-06-01

    Lipase immobilization for biodiesel production is gaining importance day by day. In this study, lipase from Burkholderia cepacia was immobilized on activated support materials namely rice husk and egg shell membrane. Both rice husk and eggshell membrane are natural wastes that holds a lot of potential as immobilization matrix. Rice husk and eggshell membrane were activated with glutaraldehyde. Lipase was immobilized on the glutaraldehyde-activated support material through adsorption. Immobilization efficiency together with enzyme activity was observed to choose the highest enzyme loading for further stability studies. Immobilization efficiency of lipase on rice husk was 81 as compared to an immobilization efficiency of 87 on eggshell membrane. Immobilized lipase on eggshell membrane exhibited higher enzyme activity as compared to immobilized lipase on rice husk. Eggshell membrane also reported higher stability than rice husk as immobilization matrix. Both types of immobilized lipase retatined its activity after ten cycles of reuse. In short, eggshell membrane showed to be a better immobilization platform for lipase as compared to rice husk. However, with further improvement in technique of immobilization, the stability of both types of immobilized lipase can be improved to a greater extent.

  13. Digestibility, Milk Production, and Udder Health of Etawah Goats Fed with Fermented Coffee Husk

    Directory of Open Access Journals (Sweden)

    I. Badarina

    2015-04-01

    Full Text Available This study was carried out to assess the utilization of coffee husk fermented by Pleurotus ostreatus as feed supplement by measuring the digestibility, milk production and udder health of Etawah goats suffered from subclinical mastitis (+1. There were three experimental diets consisted of T0 (control diet/basal diet without fermented coffee husk, T1 (basal diet with 6% fermented coffee husk and T2 (basal diet with 6% fermented coffee husk soaked in crude palm oil for an hour before using. Basal diet consisted of napier grass (60% and concentrate (40%. The results showed that supplementation of lactating Etawah does with fermented coffee husk did not affect the palatability of the diets, but increased the protein and crude fiber consumption (P<0.05. There was no significant effect on nutrient digestibility and milk production while milk composition (protein, fat, total solid increased in supplemented groups (P<0.05. The persistency of milk production and the somatic cells count were not different. There was an improvement of somatic cells count on supplemented groups. In conclusion, fermented coffee husk could be used as feed supplement without any negative effects on digestibility and milk production. The positive effects to udder health could be expected from including fermented coffee husk in diets.

  14. Increased water resistance of CTMP fibers by oat (Avena sativa L.) husk lignin.

    Science.gov (United States)

    Sipponen, Mika H; Pastinen, Ossi A; Strengell, Reetta; Hyötyläinen, Juha M I; Heiskanen, Isto T; Laakso, Simo

    2010-12-13

    The insertion of oat husk lignin onto chemithermomechanical pulp (CTMP) fibers was studied to increase fiber hydrophobicity. The pretreated pulp samples were subsequently used for preparation of handsheets for characterization. Treatment of CTMP with laccase in the presence of oat husk lignin resulted in a significant increase in hydrophobicity of the handsheet surface, as indicated by dynamic contact angle analysis. Water absorption time of 8 s was obtained with initial contact angle of 118°. Although the handsheet's brightness was reduced by 33%, tensile index was only subtly decreased. Neither laccase nor oat husk lignin alone gave much improved water absorption times. Therefore, handsheets made of laccase-treated pulp with and without oat husk lignin were further examined by XPS, which suggested that both laccase and oat husk lignin were inserted onto CTMP fibers. The oat husk lignin was distributed as heterogeneous aggregates on the handsheet surface whereas laccase was uniformly distributed. Evidence was obtained that the adsorbed laccase layer formed a noncovalent base for the insertion of oat husk lignin onto fiber surfaces.

  15. Gas generation in incinerator ash; Gasbildning i aska

    Energy Technology Data Exchange (ETDEWEB)

    Arm, Maria; Lindeberg, Johanna; Rodin, Aasa; Oehrstroem, Anna; Backman, Rainer; Oehman, Marcus; Bostroem, Dan

    2006-02-15

    other reactive metals in addition to aluminium (iron, copper and led were tested), the combination of high total aluminium content of an ash material and low volume of gas generation is possible, since the total aluminium content comprises both the elemental and the non-elemental aluminium and it is only the elemental aluminium that generates gas, aluminium particles can survive incineration without melting and without substantial oxidation of the particle surface, solid aluminium oxide (Al{sub 2}O{sub 3}) is the stable form of aluminium in a boiler. Based on the results in this project the following recommendations for handling the ash can be given to decrease the gas generation and to prevent the risk for explosion: The content of elemental aluminium or the potential of gas generation should be analysed regularly for ash materials from municipal waste incineration plants; Metal separation - including non-magnetic metals - of the fuel for waste incineration plants is necessary; Good ventilation of the ash after wetting, together with storage in oxygen rich environment is desirable.

  16. Influence of Psyllium husk (Plantago ovata on Bread Quality

    Directory of Open Access Journals (Sweden)

    Simona Maria MAN

    2017-05-01

    Full Text Available It is well supported that a significant intake of dietary fibre reduces the risk of several chronic diseases. The development of staple foods enriched with fibre is an important contribution to a broader supply of food products with health beneficial effect. In this sense, the objective of this work is the development of bread enriched with psyllium fibre. Four experimental variants obtained by substituting wheat flour with different proportions (0%, 5%, 10%, and 15% of psyllium husk were used. Bread samples were subjected to physico-chemical examination: humidity, weight, volume and specific volume of bread, crumb porosity and elasticity (according to STAS 91 -2007. The results showed an increment for the hydration capacity of the dough. The volume of the breads decreased as the level of psyllium husk increased, due the dilution of gluten content in the blend and due to the interactions among fiber components, water and gluten. Nevertheless, substitution at 5%, 10% and 15%,  gave quality parameters at least as good as for the control sample and produced acceptable bread, in terms of weight, volume and rheological properties.

  17. Antimicrobial activity of fermented Theobroma cacao pod husk extract.

    Science.gov (United States)

    Santos, R X; Oliveira, D A; Sodré, G A; Gosmann, G; Brendel, M; Pungartnik, C

    2014-09-26

    Theobroma cacao L. contains more than 500 different chemical compounds some of which have been traditionally used for their antioxidant, anti-carcinogenic, immunomodulatory, vasodilatory, analgesic, and antimicrobial activities. Spontaneous aerobic fermentation of cacao husks yields a crude husk extract (CHE) with antimicrobial activity. CHE was fractioned by solvent partition with polar solvent extraction or by silica gel chromatography and a total of 12 sub-fractions were analyzed for chemical composition and bioactivity. CHE was effective against the yeast Saccharomyces cerevisiae and the basidiomycete Moniliophthora perniciosa. Antibacterial activity was determined using 6 strains: Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis (Gram-positive) and Pseudomonas aeruginosa, Klebsiella pneumoniae, and Salmonella choleraesuis (Gram-negative). At doses up to 10 mg/mL, CHE was not effective against the Gram-positive bacteria tested but against medically important P. aeruginosa and S. choleraesuis with a minimum inhibitory concentration (MIC) of 5.0 mg/mL. Sub-fractions varied widely in activity and strongest antibacterial activity was seen with CHE8 against S. choleraesuis (MIC of 1.0 mg/mL) and CHE9 against S. epidermidis (MIC of 2.5 mg/mL). All bioactive CHE fractions contained phenols, steroids, or terpenes, but no saponins. Fraction CHE9 contained flavonoids, phenolics, steroids, and terpenes, amino acids, and alkaloids, while CHE12 had the same compounds but lacked flavonoids.

  18. Rice husk derived waste materials as partial cement replacement in lightweight concrete Utilização de resíduos derivados da casca de arroz como substitutos parciais do cimento no concreto leve

    Directory of Open Access Journals (Sweden)

    Celso Yoji Kawabata

    2012-10-01

    Full Text Available In this study rice husk ash (RHA and broiler bed ash from rice husk (BBA, two agricultural waste materials, have been assessed for use as partial cement replacement materials for application in lightweight concrete. Physical and chemical characteristics of RHA and BBA were first analyzed. Three similar types of lightweight concrete were produced, a control type in which the binder was just CEMI cement (CTL and two other types with 10% cement replacement with, respectively, RHA and BBA. All types of similar lightweight concrete were prepared to present the same workability by adjusting the amount of superplasticizer. Properties of concrete investigated were compressive and flexural strength at different ages, absorption by capillarity, resistivity and resistance to chloride ion penetration (CTH method and accelerated carbonation. Test results obtained for 10% cement replacement level in lightweight concrete indicate that although the addition of BBA conducted to lower performance in terms of the degradation indicative tests, RHA led to the enhancement of mechanical properties, especially early strength and also fast ageing related results, further contributing to sustainable construction with energy saver lightweight concrete.Neste trabalho, cinzas de casca de arroz (RHA e cinzas de cama de frango (BBA, dois resíduos agrícolas, foram avaliadas para uso como substitutos parciais do cimento para produção de concreto leve. Características físicas e químicas de RHA e BBA foram analisadas. Três tipos semelhantes de concreto leve foram produzidos, um controle em que o ligante era totalmente cimento CEM I (CTL e dois outros tipos de concreto, com substituição de 10% com RHA e BBA, respectivamente. Todos os tipos de concreto leve foram feitos através do ajuste da quantidade de superplastificante para apresentarem a mesma trabalhabilidade. Propriedades de concreto investigados foram resistência à compressão e à flexão em diferentes idades

  19. Wood ash induced pH changes strongly affect soil bacterial numbers and community composition

    DEFF Research Database (Denmark)

    Bang-Andreasen, Toke; Nielsen, Jeppe T.; Voriskova, Jana

    2017-01-01

    Recirculation of wood ash from energy production to forest soil improves the sustainability of this energy production form as recycled wood ash contains nutrients that otherwise would be lost at harvest. In addition, wood-ash is beneficial to many soils due to its inherent acid......-neutralizing capabilities. However, wood ash has several ecosystem-perturbing effects like increased soil pH and pore water electrical conductivity both known to strongly impact soil bacterial numbers and community composition. Studies investigating soil bacterial community responses to wood ash application remain sparse...... and the available results are ambiguous and remain at a general taxonomic level. Here we investigate the response of bacterial communities in a spruce forest soil to wood ash addition corresponding to 0, 5, 22, and 167 t wood ash ha(-1). We used culture-based enumerations of general bacteria, Pseudomonas...

  20. Physicochemical and Antimicrobial Properties of Cocoa Pod Husk Pectin Intended as a Versatile Pharmaceutical Excipient and Nutraceutical

    Directory of Open Access Journals (Sweden)

    Ofosua Adi-Dako

    2016-01-01

    Full Text Available The physicochemical and antimicrobial properties of cocoa pod husk (CPH pectin intended as a versatile pharmaceutical excipient and nutraceutical were studied. Properties investigated include pH, moisture content, ash values, swelling index, viscosity, degree of esterification (DE, flow properties, SEM, FTIR, NMR, and elemental content. Antimicrobial screening and determination of MICs against test microorganisms were undertaken using agar diffusion and broth dilution methods, respectively. CPH pectin had a DE of 26.8% and exhibited good physicochemical properties. Pectin had good microbiological quality and exhibited pseudoplastic, shear thinning behaviour, and high swelling capacity in aqueous media. The DE, FTIR, and NMR results were similar to those of previous studies and supported highly acetylated low methoxy pectin. CPH pectin was found to be a rich source of minerals and has potential as a nutraceutical. Pectin showed dose-dependent moderate activity against gram positive and gram negative microorganisms but weak activity against Listeria spp. and A. niger. The MICs of pectin ranged from 0.5 to 4.0 mg/mL, with the highest activity against E. coli and S. aureus (MIC: 0.5–1.0 mg/mL and the lowest activity against A. niger (MIC: 2.0–4.0 mg/mL. The study has demonstrated that CPH pectin possesses the requisite properties for use as a nutraceutical and functional pharmaceutical excipient.

  1. Physicochemical and Antimicrobial Properties of Cocoa Pod Husk Pectin Intended as a Versatile Pharmaceutical Excipient and Nutraceutical

    Science.gov (United States)

    Adi-Dako, Ofosua; Frimpong Manso, Samuel; Boakye-Gyasi, Mariam EL; Sasu, Clement; Pobee, Mike

    2016-01-01

    The physicochemical and antimicrobial properties of cocoa pod husk (CPH) pectin intended as a versatile pharmaceutical excipient and nutraceutical were studied. Properties investigated include pH, moisture content, ash values, swelling index, viscosity, degree of esterification (DE), flow properties, SEM, FTIR, NMR, and elemental content. Antimicrobial screening and determination of MICs against test microorganisms were undertaken using agar diffusion and broth dilution methods, respectively. CPH pectin had a DE of 26.8% and exhibited good physicochemical properties. Pectin had good microbiological quality and exhibited pseudoplastic, shear thinning behaviour, and high swelling capacity in aqueous media. The DE, FTIR, and NMR results were similar to those of previous studies and supported highly acetylated low methoxy pectin. CPH pectin was found to be a rich source of minerals and has potential as a nutraceutical. Pectin showed dose-dependent moderate activity against gram positive and gram negative microorganisms but weak activity against Listeria spp. and A. niger. The MICs of pectin ranged from 0.5 to 4.0 mg/mL, with the highest activity against E. coli and S. aureus (MIC: 0.5–1.0 mg/mL) and the lowest activity against A. niger (MIC: 2.0–4.0 mg/mL). The study has demonstrated that CPH pectin possesses the requisite properties for use as a nutraceutical and functional pharmaceutical excipient. PMID:27066294

  2. Physicochemical and Antimicrobial Properties of Cocoa Pod Husk Pectin Intended as a Versatile Pharmaceutical Excipient and Nutraceutical.

    Science.gov (United States)

    Adi-Dako, Ofosua; Ofori-Kwakye, Kwabena; Frimpong Manso, Samuel; Boakye-Gyasi, Mariam El; Sasu, Clement; Pobee, Mike

    2016-01-01

    The physicochemical and antimicrobial properties of cocoa pod husk (CPH) pectin intended as a versatile pharmaceutical excipient and nutraceutical were studied. Properties investigated include pH, moisture content, ash values, swelling index, viscosity, degree of esterification (DE), flow properties, SEM, FTIR, NMR, and elemental content. Antimicrobial screening and determination of MICs against test microorganisms were undertaken using agar diffusion and broth dilution methods, respectively. CPH pectin had a DE of 26.8% and exhibited good physicochemical properties. Pectin had good microbiological quality and exhibited pseudoplastic, shear thinning behaviour, and high swelling capacity in aqueous media. The DE, FTIR, and NMR results were similar to those of previous studies and supported highly acetylated low methoxy pectin. CPH pectin was found to be a rich source of minerals and has potential as a nutraceutical. Pectin showed dose-dependent moderate activity against gram positive and gram negative microorganisms but weak activity against Listeria spp. and A. niger. The MICs of pectin ranged from 0.5 to 4.0 mg/mL, with the highest activity against E. coli and S. aureus (MIC: 0.5-1.0 mg/mL) and the lowest activity against A. niger (MIC: 2.0-4.0 mg/mL). The study has demonstrated that CPH pectin possesses the requisite properties for use as a nutraceutical and functional pharmaceutical excipient.

  3. Fugitive particulate emission factors for dry fly ash disposal.

    Science.gov (United States)

    Mueller, Stephen F; Mallard, Jonathan W; Mao, Qi; Shaw, Stephanie L

    2013-07-01

    fly ash emission factors (EFs) derived by this study contribute to the small existing knowledge base for a type of pollutant that will become increasingly important as ambient particulate standards become tighter. In areas that are not in attainment with standards, realistic EFs can be used for compliance modeling and can help identify which classes of sources are best targeted to achieve desired air quality levels. In addition, understanding the natural variability in fugitive fly ash emissions can suggest methods that are most likely to be successful in controlling fugitive emissions related to dry fly ash storage.

  4. Volcanic ash melting under conditions relevant to ash turbine interactions.

    Science.gov (United States)

    Song, Wenjia; Lavallée, Yan; Hess, Kai-Uwe; Kueppers, Ulrich; Cimarelli, Corrado; Dingwell, Donald B

    2016-03-02

    The ingestion of volcanic ash by jet engines is widely recognized as a potentially fatal hazard for aircraft operation. The high temperatures (1,200-2,000 °C) typical of jet engines exacerbate the impact of ash by provoking its melting and sticking to turbine parts. Estimation of this potential hazard is complicated by the fact that chemical composition, which affects the temperature at which volcanic ash becomes liquid, can vary widely amongst volcanoes. Here, based on experiments, we parameterize ash behaviour and develop a model to predict melting and sticking conditions for its global compositional range. The results of our experiments confirm that the common use of sand or dust proxy is wholly inadequate for the prediction of the behaviour of volcanic ash, leading to overestimates of sticking temperature and thus severe underestimates of the thermal hazard. Our model can be used to assess the deposition probability of volcanic ash in jet engines.

  5. Volcanic ash melting under conditions relevant to ash turbine interactions

    Science.gov (United States)

    Song, Wenjia; Lavallée, Yan; Hess, Kai-Uwe; Kueppers, Ulrich; Cimarelli, Corrado; Dingwell, Donald B.

    2016-03-01

    The ingestion of volcanic ash by jet engines is widely recognized as a potentially fatal hazard for aircraft operation. The high temperatures (1,200-2,000 °C) typical of jet engines exacerbate the impact of ash by provoking its melting and sticking to turbine parts. Estimation of this potential hazard is complicated by the fact that chemical composition, which affects the temperature at which volcanic ash becomes liquid, can vary widely amongst volcanoes. Here, based on experiments, we parameterize ash behaviour and develop a model to predict melting and sticking conditions for its global compositional range. The results of our experiments confirm that the common use of sand or dust proxy is wholly inadequate for the prediction of the behaviour of volcanic ash, leading to overestimates of sticking temperature and thus severe underestimates of the thermal hazard. Our model can be used to assess the deposition probability of volcanic ash in jet engines.

  6. Identification and quantification of phenolic and flavonoid components in straw and seed husk of some rice varieties (Oryza sativa L.) and their antioxidant properties.

    Science.gov (United States)

    Karimi, Ehsan; Mehrabanjoubani, Pooyan; Keshavarzian, Maryam; Oskoueian, Ehsan; Jaafar, Hawa Z E; Abdolzadeh, Ahmad

    2014-08-01

    Plant foods are rich sources of bioactive compounds that can act as antioxidants to prevent heart disease, reduce inflammation, reduce the incidence of cancers and diabetes. This study aimed to determine the phenolics and flavonoids profiling in three varieties of rice straw and five varieties of the seed husk of Iranian rice using high-performance liquid chromatography (HPLC). Furthermore, the antioxidant activities of the extracts were evaluated by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and nitric oxide assays. HPLC analyses showed that the gallic acid, pyrogallol, apigenin and rutin were the main phenolic and flavonoid compounds in all varieties of rice. In addition, the methanolic extracts of Hashemi and Ali Kazemi varieties showed the highest amounts of phenolic and flavonoid contents, respectively. Rice straw and husk of Iranian varieties showed considerable antioxidant activity and Hashemi indicated significantly (P rice straw and seed husk of Iranian varieties shows high antioxidant activities and they contain various types of phenolic and flavonoid compounds that could be use in food and medical industries. © 2014 Society of Chemical Industry.

  7. Ashes for organic farming

    OpenAIRE

    Kousa, T.; Heinonen, M; Suoniitty, T.; Peltonen, K

    2013-01-01

    Nowadays only eight percent of the cultivated field area is used for organic farming. The Ministry of Agriculture and Forestry has published the guidelines for the program of organic farming to diversify the supply and the consumption of organic food. The aim is to increase organically arable land to 20% by the year 2020.The demand of organic fertilizer products is strongly increasing. Interest in forestry by-products (ash, bark, zero fiber, etc.) for use in organic production has recently be...

  8. Circle of Ashes

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] Circle of Ashes This plot tells astronomers that a pulsar, the remnant of a stellar explosion, is surrounded by a disk of its own ashes. The disk, revealed by the two data points at the far right from NASA's Spitzer Space Telescope, is the first ever found around a pulsar. Astronomers believe planets might rise up out of these stellar ashes. The data in this plot, or spectrum, were taken by ground-based telescopes and Spitzer. They show that light from around the pulsar can be divided into two categories: direct light from the pulsar, and light from the dusty disk swirling around the pulsar. This excess light was detected by Spitzer's infrared array camera. Dust gives off more infrared light than the pulsar because it's cooler. The pulsar, called 4U 0142+61, was once a massive star, until about 100,000 years ago, when it blew up in a supernova explosion and scattered dusty debris into space. Some of that debris was captured into what astronomers refer to as a 'fallback disk,' now circling the leftover stellar core, or pulsar. The disk resembles protoplanetary disks around young stars, out of which planets are thought to be born. The data have been corrected to remove the effects of light scattering from dust that lies between Earth and the pulsar. The ground-based data is from the Keck I telescope atop Mauna Kea, Hawaii.

  9. Cellulose nanowhiskers from coconut husk fibers: effect of preparation conditions on their thermal and morphological behavior

    Science.gov (United States)

    Cellulose nanowhiskers were prepared by sulfuric acid hydrolysis from coconut husk fibers which had previously been submitted to a delignification process. The effects of preparation conditions on the thermal and morphological behavior of the nanocrystals were investigated. Cellulose nanowhisker sus...

  10. Soil Incorporation of Silica-Rich Rice Husk Decreases Inorganic Arsenic in Rice Grain.

    Science.gov (United States)

    Seyfferth, Angelia L; Morris, Andrew H; Gill, Rattandeep; Kearns, Kelli A; Mann, Jessica N; Paukett, Michelle; Leskanic, Corey

    2016-05-18

    Arsenic decreases rice yield, and inorganic grain As threatens human health; thus, strategies to decrease rice As are critically needed. Increased plant-available silica (Si) can decrease rice As, yet the source of Si matters. Rice husk, an underutilized and Si-rich byproduct of rice production that contains less labile C and an order of magnitude less As than rice straw, may be an economically viable Si resource to decrease rice As, yet the impact of rice husk incorporation on As in the rice-soil nexus has not been reported. This proof-of-concept study shows that rice husk incorporation to soil (1% w/w) decreases inorganic grain As by 25-50% without negatively affecting grain Cd, yield, or dissolved CH4 levels. Rice husk is a critical yet perhaps overlooked resource to improve soil quality through enhanced nutrient availability and attenuate human health risks through consumption of As-laden grain.

  11. Production of micro- and nanosilica from soil inhabiting Folsomia candida fed with treated rice husk.

    Science.gov (United States)

    Moreno-Murguía, Barbara; Soto-Mercado, Jorge R; Morales-Malacara, Juan B; Castaño, Victor M

    2015-08-01

    Rice husk was employed as a source for producing silica micro- and nanoparticles through its digestion by soil fauna. Although many physicochemical methods for producing nanostructures have been studied, the biological processes remain mostly unexplored. Alkaline hydrogen peroxide with continuous control of reaction pH allowed removal of lignin bonds while preserving most of the cell wall and the silica present in the rice husk. The accessibility of lignocellulose was achieved without removing appreciable amounts of lignin, so this agricultural byproduct can be employed as feeding material for microarthropods Folsomia candida (Collembola). When these microarthropods are placed on a substrate of treated rice husk, more than 85% of degraded material is obtained, as compared to the untreated rice husk substrate, while the silica particles obtained show a slight decrease in average size.

  12. Concentrations of Imidacloprid and Olefin-Imidacloprid Metabolite in the Walnut Husk Maggot (Diptera:Tephritidae)

    National Research Council Canada - National Science Library

    Katheryne Nix; Carla Coots; Paris Lambdin; Jerome Grant; David Paulsen; Greg Wiggins; Paul Merten

    2014-01-01

    .... Because imidacloprid has been used successfully against pests of other host plants, we investigated how it would impact larvae of the walnut husk maggot, Rhagoletis suavis (Loew), on black walnuts...

  13. Nutraceutical potential of tinctures from fruits, green husks, and leaves of Juglans regia L

    National Research Council Canada - National Science Library

    Gawlik-Dziki, Urszula; Durak, Agata; Pecio, Łukasz; Kowalska, Iwona

    2014-01-01

    The aim of this study was to assess the phenolic composition and nutraceutical potential of tinctures from fruits in two stages of maturity (F3, younger; F25, older), green husks (GH), and leaves (L) of Juglans regia L...

  14. Hydrothermal processing of rice husks: effects of severity on product distribution

    NARCIS (Netherlands)

    Vegas, R.; Kabel, M.A.; Schols, H.A.; Alonso, J.L.; Parajo, J.C.

    2008-01-01

    BACKGROUND: Treatment in aqueous media (hydrothermal or autohydrolysis reactions) is an environmentally friendly technology for fractionating lignocellulosic materials. Rice husks were subjected to hydrothermal processing under a variety of operational conditions to cause the selective breakdown of

  15. Electricity-Independent Generation of Silicon Based on the Use of Rice Husk: A Concept Process

    Science.gov (United States)

    Barati, Mansoor

    The present paper is based on a term project for final year undergraduate students, requiring them to evaluate a process for producing silicon from rice husk. The traditional method for production of silicon involves carbothermal reduction of quartz in electric arc furnaces at temperatures exceeding 2000 °C. The technology consumes a considerable amount of electrical energy as well as fossil fuels, resulting in significant CO2 emissions. A flowsheet for production of silicon metal from rice husk is laid out in this paper. The technology will consist of combustors, which will generate steam using the rice husk biomass, power generator, and electric furnace for reduction of the rice husk. Materials and energy balance calculations presented here indicate that such process can be operated independent of external electricity.

  16. Assessment of hardened characteristics of raw fly ash blended self-compacting concrete

    Directory of Open Access Journals (Sweden)

    B. Mahalingam

    2016-09-01

    Full Text Available Fly ash is widely used as a supplementary cementitious material in concrete. Due to the implementation of new thermal power plants as a consequence of electricity demand, generation of fly ash is noticeably increased. In addition to pozzolana blended cement production, it is very imperative to use raw fly ash in concrete. Earlier research studies investigated the performance of processed fly ash in blended cement production as well as in concrete. In general, ground fly ash is used in blended cement production. A comprehensive study on the performance evaluation of raw fly ash in self-compacting concrete is not available in the existing literature. Moreover, utilization of raw fly ash in special concrete such as self-compacting concrete is essential to comprehend the performance of raw fly ash blended concrete compared to ordinary Portland concrete. Additionally, it will help to achieve maximum utilization of raw fly ash as a supplementary cementitious material rather than disposal as a waste, which eventually leads to several environmental issues. In the study, raw fly ash was collected and is directly used in development of self-compacting concrete. Two mixes were cast and hardened characteristics of blended concrete were investigated. Results from the study showed comparable performance with control concrete. Furthermore, significant reduction in chloride permeability was observed for raw fly ash blended concrete.

  17. Melting Behavior of Volcanic Ash relevant to Aviation Ash Hazard

    Science.gov (United States)

    Song, W.; Hess, K.; Lavallee, Y.; Cimarelli, C.; Dingwell, D. B.

    2013-12-01

    Volcanic ash is one of the major hazards caused by volcanic eruptions. In particular, the threat to aviation from airborne volcanic ash has been widely recognized and documented. In the past 12 years, more than 60 modern jet airplanes, mostly jumbo jets, have been damaged by drifting clouds of volcanic ash that have contaminated air routes and airport facilities. Seven of these encounters are known to have caused in-flight loss of engine power to jumbo jets carrying a total of more than 2000 passengers. The primary cause of engine thrust loss is that the glass in volcanic ash particles is generated at temperatures far lower than the temperatures in the combustion chamber of a jet engine ( i.e. > 1600 oC) and when the molten volcanic ash particles leave this hottest section of the engine, the resolidified molten volcanic ash particles will be accumulated on the turbine nozzle guide vanes, which reduced the effective flow of air through the engine ultimately causing failure. Thus, it is essential to investigate the melting process and subsequent deposition behavior of volcanic ash under gas turbine conditions. Although few research studies that investigated the deposition behavior of volcanic ash at the high temperature are to be found in public domain, to the best our knowledge, no work addresses the formation of molten volcanic ash. In this work, volcanic ash produced by Santiaguito volcano in Guatemala in November 8, 2012 was selected for study because of their recent activity and potential hazard to aircraft safety. We used the method of accessing the behavior of deposit-forming impurities in high temperature boiler plants on the basis of observations of the change in shape and size of a cylindrical coal ash to study the sintering and fusion phenomena as well as determine the volcanic ash melting behavior by using characteristic temperatures by means of hot stage microscope (HSM), different thermal analysis (DTA) and Thermal Gravimetric Analysis (TGA) to

  18. Treatment of Wastewater from a Dairy Industry Using Rice Husk as Adsorbent: Treatment Efficiency, Isotherm, Thermodynamics, and Kinetics Modelling

    Directory of Open Access Journals (Sweden)

    Uttarini Pathak

    2016-01-01

    Full Text Available Effluent from milk processing unit contains soluble organics, suspended solids, and trace organics releasing gases, causing taste and odor, and imparting colour and turbidity produced as a result of high consumption of water from the manufacturing process, utilities and service section, chemicals, and residues of technological additives used in individual operations which makes it crucial matter to be treated for preserving the aesthetics of the environment. In this experimental study after determination of the initial parameters of the raw wastewater it was subjected to batch adsorption study using rice husk. The effects of contact time, initial wastewater concentration, pH, adsorbent dosage, solution temperature and the adsorption kinetics, isotherm, and thermodynamic parameters were investigated. The phenomenon of adsorption was favoured at a lower temperature and lower pH in this case. Maximum removal as high as 92.5% could be achieved using an adsorbent dosage of 5 g/L, pH of 2, and temperature of 30°C. The adsorption kinetics and the isotherm studies showed that the pseudo-second-order model and the Langmuir isotherm were the best choices to describe the adsorption behavior. The thermodynamic parameters suggested that not only was the adsorption by rice husk spontaneous and exothermic in nature but also the negative entropy change indicated enthalpy driven process.

  19. Development of edible films based on Brazilian pine seed (Araucaria angustifolia) flour reinforced with husk powder

    Science.gov (United States)

    The aim of this study was to develop edible films based on pinhão flour reinforced with pinhão husk powder. For this, six formulations were developed using 5.0% pinhão flour with 1.5% glycerol base and adding 0.5, 1.0, 1.5, 2.0 and 2.5% of pinhão husk where the pure base served as the control. The ...

  20. The potential reuse of soybean husk as feedstock of Eudrilus eugeniae in vermicomposting.

    Science.gov (United States)

    Lim, Pei Nie; Wu, Ta Yeong; Sim, Edwin Yih Shyang; Lim, Su Lin

    2011-11-01

    Soybean (Glycine max L.) is one the most commonly consumed legumes worldwide, with 200 million metric tons produced per year. However, the inedible soy husk would usually be removed during the process and the continuous generation of soybean husk may represent a major disposal problem for soybean processing industries. Thus, the main aim of the present study was to investigate the possibility to convert soybean husk (S) amended with market-rejected papaya (P) into vermicompost using Eudrilus eugeniae. Soybean husk was mixed with market-rejected papaya in different ratios to produce five different treatments (1P:1S, 2P:1S, 1P:2S, S only and P only) for laboratory screening of solid wastes. Generally, the application of E. eugeniae permitted a significant increase in Ca (42.3-91.6%), K (93.8-235%), Mg (25.4-84.6%) and P (37.1-129%) but a decrease in the C:N ratio (21.4-52.8%) after 9 weeks of vermicomposting. Among all the treatments investigated, soybean husk which was mixed with an equal amount of market-rejected papaya (1P:1S) showed superior quality vermicompost. Waste mixtures also encouraged the growth of E. eugeniae except the treatments with soybean husk alone as well as soybean husk which was mixed with market-rejected papaya in 1P:2S ratio. Vermicomposting could be used as an efficient technology to convert soybean husk into nutrient-rich organic fertiliser if it was mixed with market-rejected papaya in appropriate ratio. Copyright © 2011 Society of Chemical Industry.

  1. Investigation on Thermal Properties of Composite of Rice Husk, Corncob and Baggasse for Building Thermal Insulation

    OpenAIRE

    Kyauta E.E. Dauda D.M; Justin E

    2014-01-01

    The thermal properties of some Agricultural waste ( Rice Husk, Bagasse and Corncob) was investigated with the purpose of determining their use as insulators. Using varied composite percentages of each sample wastes at increasing and decreasing quantities to determine best mixtures has assisted in accurate recommendation. The work has explored the potentials for using composite samples of Rice Husk, Bagasse and Corncob as materials for thermal insulation, a solution which offers a reduction...

  2. Nutritive value of red vine husks and pips for sheep | Ferreira | South ...

    African Journals Online (AJOL)

    The potential of red vine husks and pips as a component of animal feed was investigated. Twenty-five Dohne Merino ram lambs (mean live weight + s.d. = 41.4 + 2.3 kg) were used. A completely randomised design was used and the animals were assigned to five diets including 0, 12.5, 25.0, 37.5 and 50% vine husks and ...

  3. Utilization of agricutural wastes (Cocoa Pod Husk) in the diet of ...

    African Journals Online (AJOL)

    The inclusion of agricultural waste (cocoa pod husk) in the diet of Clarias gariepinus was investigated in a feeding trial. Clarias gariepinus with a mean weight of 3.53±0.23g was placed on 5 test diets at inclusion levels of 0, 5, 10, 15 and 20% cocoa pod husk (CPH) for 56 days. At the end of the feeding trial, the result ...

  4. Sodium ion interaction with psyllium husk (Plantago sp.).

    Science.gov (United States)

    Jimoh, M A; MacNaughtan, W; Williams, H E L; Greetham, D; Linforth, R L; Fisk, I D

    2016-09-14

    The nature of and factors effecting sodium interactions with psyllium were investigated in vitro. In a batch extraction system, psyllium mucilage gel retained at least 50% of sodium across a range of concentrations (5-300 mg sodium per g psyllium) and pH (2-10) environments. FTIR and Na NMR analyses of psyllium gels indicated that binding was complex with non-specific multi-site interactions. The potential use of psyllium husk as a binding agent for the reduction of bioavailable sodium was therefore evaluated. The binding of sodium at physiologically relevant conditions (pH 1.2 (stomach) and 6.8 (intestine)) was studied in a gastrointestinal tract (GIT) pH simulated model. Results show consistently high sodium retention (∼50%) across the GIT model and less than 20% loss of bound sodium under the simulated intestinal pH conditions after repeated washings.

  5. Bioactive compounds in Mexican genotypes of cocoa cotyledon and husk.

    Science.gov (United States)

    Hernández-Hernández, Carolina; Viera-Alcaide, Isabel; Morales-Sillero, Ana María; Fernández-Bolaños, Juan; Rodríguez-Gutiérrez, Guillermo

    2018-02-01

    A characterization of the phenolic profile of 25 cocoa genotypes established in a Mexican gene bank was carried out. From five different extraction methods commonly used for phenols, extraction with acidified methanol-water was chosen as the best to quantify the concentrations of theobromine and individual phenols in cocoa beans. High concentrations of individual and total phenols were found for genotypes native to Mexico (like RIM105, M031, and M033) or from Peru and Ecuador (INI10), but not the commercial mix (CAF), and were directly associated with their antioxidant activities. Despite the loss of some theobromine and phenols during fermentation, epicatechin remained in the fermented cotyledon in high concentrations. This study could help promote the commercialization of Mexican genotypes of cocoa and reports the possibility of upcycling fermented cocoa husks, which are rich in bioactive compounds and fiber, as novel functional extracts for use in food formulation or for nutraceutical purposes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Combustion of Biosolids in a Bubbling Fluidized Bed, Part 1: Main Ash-Forming Elements and Ash Distribution with a Focus on Phosphorus.

    Science.gov (United States)

    Skoglund, Nils; Grimm, Alejandro; Ohman, Marcus; Boström, Dan

    2014-02-20

    This is the first in a series of three papers describing combustion of biosolids in a 5-kW bubbling fluidized bed, the ash chemistry, and possible application of the ash produced as a fertilizing agent. This part of the study aims to clarify whether the distribution of main ash forming elements from biosolids can be changed by modifying the fuel matrix, the crystalline compounds of which can be identified in the raw materials and what role the total composition may play for which compounds are formed during combustion. The biosolids were subjected to low-temperature ashing to investigate which crystalline compounds that were present in the raw materials. Combustion experiments of two different types of biosolids were conducted in a 5-kW benchscale bubbling fluidized bed at two different bed temperatures and with two different additives. The additives were chosen to investigate whether the addition of alkali (K 2 CO 3 ) and alkaline-earth metal (CaCO 3 ) would affect the speciation of phosphorus, so the molar ratios targeted in modified fuels were P:K = 1:1 and P:K:Ca = 1:1:1, respectively. After combustion the ash fractions were collected, the ash distribution was determined and the ash fractions were analyzed with regards to elemental composition (ICP-AES and SEM-EDS) and part of the bed ash was also analyzed qualitatively using XRD. There was no evidence of zeolites in the unmodified fuels, based on low-temperature ashing. During combustion, the biosolid pellets formed large bed ash particles, ash pellets, which contained most of the total ash content (54%-95% (w/w)). This ash fraction contained most of the phosphorus found in the ash and the only phosphate that was identified was a whitlockite, Ca 9 (K,Mg,Fe)(PO 4 ) 7 , for all fuels and fuel mixtures. With the addition of potassium, cristobalite (SiO 2 ) could no longer be identified via X-ray diffraction (XRD) in the bed ash particles and leucite (KAlSi 2 O 6 ) was formed. Most of the alkaline-earth metals

  7. Seeding effect on cocomposting wastewater biosolids with coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Fang, M.; Wong, J.W.C. [Hong Kong Baptist University, Hong Kong (China). Dept. of Biology

    2001-10-01

    The seeding effect on fly ash-amended biosolids composting was evaluated by inoculating a mixture of ash and biosolids with seeding materials before composting. These inocula included thermophilic bacteria (Bacillus. brevis, B. coagulans, and B. licheniformis) isolated from the ash-biosolids compost, a commercial decomposter, and recycled biosolids compost. Although the addition of these microbial additives to the ash-biosolids compost improved the population of thermophilic bacteria at the early stage of composting, the improvement was negligible after 4 days of composting. Inoculation with isolated bacterial culture, milk powder, or the decomposter, only, did not effectively improve the decomposition of organic matter compared with those receiving inoculation of both microbial additives and milk powder together. The isolated Bacillus species was as efficient as the commercial decomposter in accelerating the decomposition rate during ash-amended biosolids composting as indicated by the high amounts of carbon dioxide evolved and cumulative weight loss. Taking into consideration the lower operating cost and acceptable decomposition efficiency, recycled biosolids compost seemed to be a promising additive to ash-amended biosolids compost to improve composting efficiency.

  8. Physical, chemical and mechanical properties of pehuen cellulosic husk and its pehuen-starch based composites.

    Science.gov (United States)

    Castaño, J; Rodríguez-Llamazares, S; Carrasco, C; Bouza, R

    2012-11-06

    Pehuen cellulosic husk was characterized and employed as reinforcement for composite materials. In this research, thermoplastic pehuen starch (TPS) and TPS/poly(lactic acid) (PLA)/polyvinyl alcohol (PVA) composites, reinforced with 5 and 10% of pehuen husk, were prepared by melt-blending. Comparative samples of pehuen TPS and TPS/PLA/PVA blend were also studied. Physical, thermal, structural and mechanical properties of composites were evaluated. Pehuen husk mainly consists of cellulose (50 wt%), hemicellulose (30 wt%) and lignin (14 wt%). In respect to lipids, this husk has only a 0.6 wt%. Its surface is smooth and damage-free and it is decomposed above 325 °C. The incorporation of pehuen husk improved considerably the thermal stability and mechanical properties of the studied composites, mainly in TPS composites. Their thermal stability enhances since biofiber hinders the "out-diffusion" of volatile molecules from the polymer matrix, while mechanical properties could raise due to the natural affinity between husk and starch in the pehuen seed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Husk Tomato (Physalis ixocarpa Brot.) Waste as a Promising Source of Pectin: Extraction and Physicochemical Characterization.

    Science.gov (United States)

    Morales-Contreras, Blanca Elizabeth; Contreras-Esquivel, Juan Carlos; Wicker, Louise; Ochoa-Martínez, Luz Araceli; Morales-Castro, Juliana

    2017-07-01

    Husk tomato (Physalis ixocarpa Brot. var. Rendidora) waste was evaluated as a source of specialized pectin, and pectin extracted from this waste was characterized physicochemically. Fruit was blanched for 10 or 15 min and extracted in 0.1 N HCl for 15 to 25 min. Extracted pectin was subjected to physicochemical analysis. For all extraction conditions, the percentage of anhydrogalacturonic acid exceeded 60%, indicating that husk tomato was a good source of pectin. The degree of esterification of pectin molecules was 63% to 91%. The amount of extracted pectin decreased with increasing extraction time. The apparent viscosity of husk tomato pectin showed the characteristic behavior of pseudoplastic fluids. Neutral sugars were identified, and the amounts of 6 sugars (fucose, rhamnose, arabinose, galactose, glucose, and xylose) were quantified. Sugars identified in husk tomato pectin and present in the Rhamnogalacturonan I region, arabinose, galactose, and rhamnose suggest a highly branched structure, which will influence its future applications. Molecular weight values were 542 to 699 kDa, exceeding molecular weight values reported for commercial citrus pectins from 134 to 480 kDa. The extraction process significantly (P < 0.05) influenced the physicochemical properties of pectin. Up to 19.8% from the total amount of pectin in the husk tomato was extracted by 10 min of blanching and 20 min of a more heat treatment. Our findings indicate that husk tomato can be a good alternative source of pectin having highly distinctive physicochemical characteristics. © 2017 Institute of Food Technologists®.

  10. Bioethanol production from steam-exploded rice husk by recombinant Escherichia coli KO11.

    Science.gov (United States)

    Tabata, Takamitsu; Yoshiba, Yusuke; Takashina, Tomonori; Hieda, Kazuo; Shimizu, Norio

    2017-03-01

    Rice husk is one of the most abundant types of lignocellulosic biomass. Because of its significant amount of sugars, such as cellulose and hemicellulose, it can be used for the production of biofuels such as bioethanol. However, the complex structure of lignocellulosic biomass, consisting of cellulose, hemicellulose and lignin, is resistant to degradation, which limits biomass utilization for ethanol production. The protection of cellulose by lignin contributes to the recalcitrance of lignocelluloses to hydrolysis. Therefore, we conducted steam-explosion treatment as pretreatment of rice husk. However, recombinant Escherichia coli KO11 did not ferment the reducing sugar solution obtained by enzymatic saccharification of steam-exploded rice husk. When the steam-exploded rice husk was washed with hot water to remove inhibitory substances and M9 medium (without glucose) was used as a fermentation medium, E. coli KO11 completely fermented the reducing sugar solution obtained by enzymatic saccharification of hot water washing-treated steam-exploded rice husk to ethanol. We report here the efficient production of bioethanol using steam-exploded rice husk.

  11. Effects of Cocoa Husk Feeding on the Composition of Swine Intestinal Microbiota.

    Science.gov (United States)

    Magistrelli, Damiano; Zanchi, Raffaella; Malagutti, Luca; Galassi, Gianluca; Canzi, Enrica; Rosi, Fabia

    2016-03-16

    A two-diet/two-period change over experiment was performed to investigate the effects of cocoa husks, as a source of dietary fiber and polyphenols, on pig intestinal microbial composition. Six pigs were fed a conventional cereal-based diet or a diet obtained by substitution of 7.5% of the conventional diet with cocoa husks for 3 weeks. Experimental diets were isoproteic and isoenergetic. At the end of each 3 week testing period, samples of fresh feces were collected and analyzed for microbial composition by fluorescence in situ hybridization. Cocoa husks did not affect feed intake, weight gain, and feed efficiency. Analysis of fecal microbial populations, grouped by phyla, showed a decrease of Firmicutes and an increase of Bacteroidetes in cocoa husk-fed pigs. Particularly, cocoa husks reduced fecal populations of the Lactobacillus-Enterococcus group and Clostridium histolyticum and increased the Bacteroides-Prevotella group and Faecalibacterium prausnitzii, suggesting a potential for cocoa husks in the improvement of intestinal microbial balance.

  12. Stimulation of mycelia growth in several mushroom species by rice husks.

    Science.gov (United States)

    Hanai, Hidetoshi; Ishida, Sayuri; Saito, Chiaki; Maita, Tetsuya; Kusano, Miyako; Tamogami, Shigeru; Noma, Masana

    2005-01-01

    When supplemented to the culture medium of mushroom Coprinus cinereus, rice husks soaked beforehand in methanol stimulated mycelia growth up to a concentration of 80 mg/ml dose-dependently, whereas the non-treated stimulated mycelia growth up to 20 mg/ml. This result suggests the existence of both stimulatory and inhibitory substances in rice husks. Since momilactone A (MLA) is recognized as one of the phytoalexins in rice husks, its biological activity against mycelia growth was tested. Momilactone A inhibited mycelia growth at 5 microg/disc, whereas the methanol extract of husks did so at 1 mg/disc, wherein 0.2 microg of MLA was estimated by LC/MS/MS. Thus the phytoalexins including MLA should inhibit mycelia growth. Rice husks stimulated mycelia growth in some edible mushroom species such as Grifola frondosa (maitake), Lentinus edodes (shiitake), Pleurotus eryngii (eringi), and P. ostreatus (hiratake). Our findings might lead to the development of new profitable cultivation methods for mushrooms using rice husks.

  13. Biosorption of Am-241 and Cs-137 by radioactive liquid waste by coffee husk

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Rafael Vicente de Padua; Sakata, Solange Kazumi; Bellini, Maria Helena; Marumo, Julio Takehiro, E-mail: jtmarumo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Radioactive Waste Management Laboratory of Nuclear and Energy Research Institute, IPEN-CNEN/SP, has stored many types of radioactive liquid wastes, including liquid scintillators, mixed wastes from chemical analysis and spent decontamination solutions. These wastes need special attention, because the available treatment processes are often expensive and difficult to manage. Biosorption using biomass of vegetable using agricultural waste has become a very attractive technique because it involves the removal of heavy metals ions by low cost biossorbents. The aim of this study is to evaluate the potential of the coffee husk to remove Am-241 and Cs-137 from radioactive liquid waste. The coffee husk was tested in two forms, treated and untreated. The chemical treatment of the coffee husk was performed with HNO{sub 3} and NaOH diluted solutions. The results showed that the coffee husk did not showed significant differences in behavior and capacity for biosorption for Am-241 and Cs-137 over time. Coffee husk showed low biosorption capacity for Cs-137, removing only 7.2 {+-} 1.0% in 4 hours of contact time. For Am-241, the maximum biosorption was 57,5 {+-} 0.6% in 1 hours. These results suggest that coffee husk in untreated form can be used in the treatment of radioactive waste liquid containing Am-241. (author)

  14. A review of the interference of carbon containing fly ash with air entrainment in concrete

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard; Jensen, Anker Degn; Skjøth-Rasmussen, Martin Skov

    2008-01-01

    Industrial utilization of fly ash from pulverized coal combustion plays an important role in environmentally clean and cost effective power generation. Today, the primary market for fly ash utilization is as pozzolanic additive in the production of concrete. However, the residual carbon in fly ash...... on the adsorption capacity of AEAs. The type of fuel used in the combustion process influences the amount and properties of the residual carbon. Fly ash derived from bituminous coal has generally higher carbon content compared with fly ash produced from subbituminous coal or lignite, but shows a lower AEA......-treatment methods applied to improve fly ash quality are described in the review. Ozonation, thermal treatment and physical cleaning of carbon have been found to improve the fly ash performance for concrete utilization. Ultimately, recommendations for further work are outlined in the discussion....

  15. Influence of wheat ash on the MCPA immobilization in agricultural soils.

    Science.gov (United States)

    Hiller, E; Fargasová, A; Zemanová, L; Bartal, M

    2008-09-01

    Burning of crop residues in the fields is a routine post-harvest practice and results in accumulation of ashes in soils. Recent studies have shown that the ashes may significantly contribute to the herbicide sorption in soils. This study was conducted to evaluate the potential role of wheat ash in immobilization of anionic herbicide MCPA in soils. The results showed that wheat ash is highly effective sorbent for herbicide MCPA. Amendment of Fluvi-Gleyic Phaeozem and Eutric Regosol with 1% wheat ash caused a 8-fold and 16-fold increase in MCPA sorption, respectively. Desorption of MCPA was also influenced by wheat ash in soils. The addition of wheat ash to both soils increased the resistant fraction to desorption up to 80%. Generally, the field burning of crop residues appears to increase the sorption of pesticides in agricultural soils and decrease their leaching.

  16. Effects of Kenaf and Rice Husk on Water Absorption and Flexural Properties of Kenaf/CaCO3/HDPE and Rice Husk/CaCO3/HDPE Hybrid Composites

    OpenAIRE

    Noor Zuhaira Abd Aziz; Rahmah Mohamed; Mohd Muizz Fahimi M.

    2015-01-01

    Rice husk and kenaf filled with calcium carbonate (CaCO3) and high density polyethylene (HDPE) composite were prepared separately using twin-screw extruder at 50rpm. Different filler loading up to 30 parts of rice husk particulate and kenaf fiber were mixed with the fixed 30% amount of CaCO3 mineral filler to produce rice husk/CaCO3/HDPE and kenaf/CaCO3/HDPE hybrid composites. In this study, the effects of natural fiber for both rice husk and kenaf in CaCO3/HDPE composite...

  17. Leaching from biomass combustion ash

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard

    2014-01-01

    The use of biomass combustion ashes for fertilizing and liming purposes has been widely addressed in scientific literature. Nevertheless, the content of potentially toxic compounds raises concerns for a possible contamination of the soil. During this study five ash samples generated at four...... in water. The content of the selected heavy metals (i.e. Cr, Ni, Pb and Cd) complied with the Danish Statutory Order on the use of bio-ash for agricultural purposes; however, critical releases of Cr were detected in the leachate extracts, especially in the fly ash. High alkaline pHs were measured in all...

  18. Utilization of coal fly ash in solidification of liquid radioactive waste from research reactor.

    Science.gov (United States)

    Osmanlioglu, Ahmet Erdal

    2014-05-01

    In this study, the potential utilization of fly ash was investigated as an additive in solidification process of radioactive waste sludge from research reactor. Coal formations include various percentages of natural radioactive elements; therefore, coal fly ash includes various levels of radioactivity. For this reason, fly ashes have to be evaluated for potential environmental implications in case of further usage in any construction material. But for use in solidification of radioactive sludge, the radiological effects of fly ash are in the range of radioactive waste management limits. The results show that fly ash has a strong fixing capacity for radioactive isotopes. Specimens with addition of 5-15% fly ash to concrete was observed to be sufficient to achieve the target compressive strength of 20 MPa required for near-surface disposal. An optimum mixture comprising 15% fly ash, 35% cement, and 50% radioactive waste sludge could provide the solidification required for long-term storage and disposal. The codisposal of radioactive fly ash with radioactive sludge by solidification decreases the usage of cement in solidification process. By this method, radioactive fly ash can become a valuable additive instead of industrial waste. This study supports the utilization of fly ash in industry and the solidification of radioactive waste in the nuclear industry.

  19. The influence of Rice Husk Fiber on The Properties of Epoxidized Natural Rubber/Rice Husk Compounds

    Directory of Open Access Journals (Sweden)

    Dahham Omar S.

    2016-01-01

    Full Text Available In this work, curing characteristics, tensile and physical properties of epoxidized natural rubber/rice husk (ENR-50/RH compounds were investigated. Different RH loading (10, 20, 30, 40 and 50 Phr and size (fine size at 100-300 μm and coarse size at 5-10 mm were prepared and used. Results indicated that the scorch time (t2 and cure time (t90 became shorter with increasing RH content. In contrast, minimum torque (ML and maximum torque (MH increased with increasing RH content in the rubber compounds. Hardness and crosslink density showed improvement with increasing RH content. Tensile strength (Ts and elongation at break (Eb decreased slightly as RH content increased. However, the fine size of RH recorded better overall properties compared to the RH coarse size at same loading the rubber compound.

  20. Fly ash quality and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Barta, L.E.; Lachner, L.; Wenzel, G.B. [Inst. for Energy, Budapest (Hungary); Beer, M.J. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

    1995-12-01

    The quality of fly ash is of considerable importance to fly ash utilizers. The fly ash puzzolanic activity is one of the most important properties that determines the role of fly ash as a binding agent in the cementing process. The puzzolanic activity, however is a function of fly ash particle size and chemical composition. These parameters are closely related to the process of fly ash formation in pulverized coal fired furnaces. In turn, it is essential to understand the transformation of mineral matter during coal combustion. Due to the particle-to-particle variation of coal properties and the random coalescence of mineral particles, the properties of fly ash particles e.g. size, SiO{sub 2} content, viscosity can change considerably from particle to particle. These variations can be described by the use of the probability theory. Since the mean values of these randomly changing parameters are not sufficient to describe the behavior of individual fly ash particles during the formation of concrete, therefore it is necessary to investigate the distribution of these variables. Examples of these variations were examined by the Computer Controlled Scanning Electron Microscopy (CCSEM) for particle size and chemical composition for Texas lignite and Eagel Butte mineral matter and fly ash. The effect of combustion on the variations of these properties for both the fly ash and mineral matter were studied by using a laminar flow reactor. It is shown in our paper, that there are significant variations (about 40-50% around the mean values) of the above-listed properties for both coal samples. By comparing the particle size and chemical composition distributions of the mineral matter and fly ash, it was possible to conclude that for the Texas lignite mineral matter, the combustion did not effect significantly the distribution of these properties, however, for the Eagel Butte coal the combustion had a major impact on these mineral matter parameters.

  1. A novel vortex-fluidized bed combustor with two combustion chambers for rice-husk fuel

    Directory of Open Access Journals (Sweden)

    Madhiyanon, T.

    2004-11-01

    Full Text Available A novel vortexing-fluidized bed combustor (VFBC using rice-husk as fuel was developed and presented. The combined characteristics of vortex combustion and fluidized bed combustion are the main features of the VFBC, which was designed to achieve high thermal capacity (MWth m-3, high thermal efficiency and low diameter to height ratio. The VFBC comprises a vertical cylinder chamber and a conical base, which provides a bed for incompletely combusted fuel. The overall dimensions are 1.10 m in height and 0.40 m in diameter. To evaluate combustor performance, the specific feed rate of fuel and mass flow rates of the primary, secondary, and tertiary air were varied independently of one another. The combustion appeared into two zones characterized by different combustion behaviors, i.e. 1 vortext combustion above the vortex ring and 2 fluidized bed combustion below the vortex ring. The fluidized bed zone has uniform temperature distributions across the cross-section of the combustor. The swirling of air above the vortex ringand the vortex ring itself played important roles in preventing the escape of combustion particulates. Bottomash appeared as fine black and grey particles of ash, which ranged in size from 200 to 600 µm. Fluidizationcould be initiated without the assistance of any inert material mixed into the bed. The experimental resultsindicated that thermal efficiency did not depend on the secondary or tertiary airflows, but was significantlyinfluenced by the excess air resulting from the combined total of the three airflows. The introduction of thetertiary airflow helped maintaining the temperature inside the combustor within acceptable levels. According to experimental conditions, i.e. a specific feed rate of 240 kg h-1m-3 and excess air (157%, it was found that the VFBC could achieve an exit gas temperature of 1060ºC, thermal efficiency of 95%, and thermal capacity of 0.91 MWth m-3. The amounts of CO2, CO, and O2 gases emitted were directly

  2. Ash Properties of Alternative Biomass

    DEFF Research Database (Denmark)

    Capablo, Joaquin; Jensen, Peter Arendt; Pedersen, Kim Hougaard

    2009-01-01

    The ash behavior during suspension firing of 12 alternative solid biofuels, such as pectin waste, mash from a beer brewery, or waste from cigarette production have been studied and compared to wood and straw ash behavior. Laboratory suspension firing tests were performed on an entrained flow...

  3. Dielectric properties of fly ash

    Indian Academy of Sciences (India)

    Unknown

    Abstract. This paper reports the dielectric properties of fly ash. The dielectric measurements were performed as a function of frequency and temperature. The sample of fly ash shows almost similar behaviour in the frequency and temperature range studied. The large value of dielectric constant in the typical frequency range.

  4. Common Ash (Fraxinus excelsior L.)

    NARCIS (Netherlands)

    Douglas, G.C.; Pliura, A.; Dufour, J.; Mertens, P.; Jacques, D.; Buiteveld, J.

    2013-01-01

    Common ash (Fraxinus excelsior L.) has an extensive natural distribution across Europe and extends as far east as the Volga river and south into northern Iran. Country statistics and national programmes show that common ash has major economic and ecological importance in many countries. Genetic

  5. Emerald ash borer life cycle

    Science.gov (United States)

    Leah S. Bauer; Robert A. Haack; Deborah L. Miller; Toby R. Petrice; Houping Liu

    2004-01-01

    The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), native to several Asian countries, was discovered in southeastern Michigan and nearby Ontario in June of 2002. EAB was identified as the cause of extensive ash (Fraxinus spp.) mortality in approximately 2,500 mi2, and...

  6. Organic pollutants profiling of wood ashes from biomass power plants linked to the ash characteristics.

    Science.gov (United States)

    Rey-Salgueiro, Ledicia; Omil, Beatriz; Merino, Agustín; Martínez-Carballo, Elena; Simal-Gándara, Jesús

    2016-02-15

    Wood ash, characterized by high content of certain nutrients and charcoal, can be applied to soils as a means of managing this waste product improving the soil quality. The associated environmental risk must be assessed. The objective of this study was to characterize the bottom and fly ash collected from 15 biomass power plants in Spain by determining the benzene, toluene, ethylbenzene, xylene and styrene (BTEX+S), PAHs and aliphatic hydrocarbon contents of both types of ash. Biochar was also used for comparison purposes. Gas chromatography-mass spectrometric methods were used for the identification and determination of both BTEX+S and aliphatic hydrocarbon contents in bottom and fly ashes, as well as biochar. High performance liquid chromatography with fluorescence detection was used for PAHs measurements. Multivariate correlation analysis was used to determine the relationship between sample characteristics and pollutants identified by partial least squares regression analysis. In general, the degree to which organic matter in the sample is burned increases with T50 or the "50% burn off" temperature (possibly due to the addition of fuel), and the BTEX+S also tended to increase. However, as the Q/MO (the heat of combustion divided by organic matter mass) increased, the combustion decreased or proceeded with less oxygen, which appears to be related to an increased presence of PAHs. The results confirm that the amounts of organic pollutants (PAHs and BTEX+S, together with total aliphatic hydrocarbons) in the wood ash do not exceed limits established for different soil or industrial uses. Both types of ash, together with biochar, may therefore be suitable for application to soil as a fertilizer and an organic amendment, taking into account the target organic pollutants. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Recoverable immobilization of transuranic elements in sulfate ash

    Science.gov (United States)

    Greenhalgh, Wilbur O.

    1985-01-01

    Disclosed is a method of reversibly immobilizing sulfate ash at least about 20% of which is sulfates of transuranic elements. The ash is mixed with a metal which can be aluminum, cerium, samarium, europium, or a mixture thereof, in amounts sufficient to form an alloy with the transuranic elements, plus an additional amount to reduce the transuranic element sulfates to elemental form. Also added to the ash is a fluxing agent in an amount sufficient to lower the percentage of the transuranic element sulfates to about 1% to about 10%. The mixture of the ash, metal, and fluxing agent is heated to a temperature sufficient to melt the fluxing agent and the metal. The mixture is then cooled and the alloy is separated from the remainder of the mixture.

  8. Ash properties of some dominant Greek forest species

    Energy Technology Data Exchange (ETDEWEB)

    Liodakis, S. [Laboratory of Inorganic and Analytical Chemistry, Department of Chemical Engineering, National Technical University of Athens (NTUA), 9 Iroon Polytechniou Street, Athens 157 73 (Greece)]. E-mail: liodakis@central.ntua.gr; Katsigiannis, G. [Laboratory of Inorganic and Analytical Chemistry, Department of Chemical Engineering, National Technical University of Athens (NTUA), 9 Iroon Polytechniou Street, Athens 157 73 (Greece); Kakali, G. [Laboratory of Inorganic and Analytical Chemistry, Department of Chemical Engineering, National Technical University of Athens (NTUA), 9 Iroon Polytechniou Street, Athens 157 73 (Greece)

    2005-10-15

    The elemental and chemical wood ash compositions of six dominant Greek fuels was investigated using a variety of techniques, including thermal gravimetric analysis (TG), differential thermal analysis (DTA), atomic absorption spectroscopy (AAS) and X-ray diffraction (XRD). In addition, the alkalinity of wood ash was determined by titration. The ash was prepared by combustion at low (600 deg. C), middle (800 deg. C) and high temperatures (1000 deg. C). The ash composition is very important because thousands of hectares of wildlands are burned annually in Greece. The resulting deposits affect soil properties (i.e., pH) and provide a source of inorganic constituents (i.e., Ca, K, Na, Mg, etc.), while the most soluble compounds (i.e., sodium and potassium hydroxides and carbonates) do not persist through the wet season. The samples selected were: Pinus halepensis (Aleppo pine), Pinus brutia (Calabrian pine), Olea europaea (Olive), Cupressus sempervirens (Italian cypress), Pistacia lentiscus (Mastic tree), Quercus coccifera (Holly oak)

  9. Pretreatment and utilization of waste incineration bottom ashes

    DEFF Research Database (Denmark)

    Astrup, Thomas

    2007-01-01

    , however, have had a strong emphasis on lab experiments with little focus on full scale bottom ash upgrading methods. The introduction of regulatory limit values restricting leaching from utilized bottom ashes, has created a need for a better understanding of how lab scale experiences can be utilized....../aging, washing with and without additives, organic matter, sampling techniques, utilization options, and assessment tools. This paper provides an overview of these projects. The main results and experiences are discussed and evaluated with respect to bottom ash upgrading and utilization. Based on this discussion......Within recent years, researchers and authorities have had increasing focus on leaching properties from waste incineration bottom ashes. Researchers have investigated processes such as those related to carbonation, weathering, metal complexation, and leaching control. Most of these investigations...

  10. Qualitative Analysis of Polyphenols in Macroporous Resin Pretreated Pomegranate Husk Extract by HPLC-QTOF-MS.

    Science.gov (United States)

    Abdulla, Rahima; Mansur, Sanawar; Lai, Haizhong; Ubul, Ablikim; Sun, Guangying; Huang, Guozheng; Aisa, Haji Akber

    2017-09-01

    Pomegranate (Punica granatum L.) husk is a traditional herbal medicine abundant in phenolic compounds and plays some roles in the treatment of oxidative stress, bacterial and viral infection, diabetes mellitus, and acute and chronic inflammation. Identification and determination of polyphenols in macroporous resin pretreated pomegranate husk extract by high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS). The total polyphenols of pomegranate husk were prepared by ethanol extraction followed by pretreatment with HPD-300 macroporous resin. The polyphenolic compounds were qualitatively analysed by HPLC-QTOF-MS in negative electrospray ionisation (ESI) mode at different collision energy (CE) values. A total of 50 polyphenols were detected in the extract of pomegranate husk, including 35 hydrolysable tannins and 15 flavonoids with distinct retention time, fragmentation behaviours and characteristics, and the accurate mass-to-charge ratios at low, moderate and high CE values. Of these, we identified nine compounds for the first time in the pomegranate husk, including hexahydroxydiphenoyl-valoneoyl-glucoside (HHDP-valoneyl-glucoside), galloyl-O-punicalin, rutin, hyperoside, quercimeritrin, kaempferol-7-O-rhahmano-glucoside, luteolin-3'-O-arabinoside, luteolin-3'-O-glucoside, and luteolin-4'-O-glucoside. To validate the specificity and accuracy of mass spectrometry in the detection of polyphenols, as compared to the fragmentation pathways of granatin B in detail, including the HHDP-valoneyl- glucoside was first identified from pomegranate husk. The study provides evidence for the quality control and development of novel drugs based on polyphenols from the pomegranate husk. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  11. Effect of soybean husk supplementation on the fecal fermentation metabolites and microbiota of dogs.

    Science.gov (United States)

    Myint, Htun; Iwahashi, Yu; Koike, Satoshi; Kobayashi, Yasuo

    2017-11-01

    In vitro fermentation and in vivo feeding experiments were conducted to characterize the effects of soybean (Glycine max) husk on the fecal fermentation metabolites and microbiota of dogs. An in vitro fermentation study using feces from three Toy Poodle dogs (6.5 ± 3.5 months in age and 2.9 ± 0.4 kg in body weight) revealed that the fecal inoculum was able to ferment soybean husk (supplemented at 0.01 g/mL culture) and increased levels of short chain fatty acids (SCFA) and Bifidobacterium, irrespective of pre-digestion of the husk by pepsin and pancreatin. In a feeding experiment, four Shiba dogs (7-48 months in age and 7.5 ± 1.7 kg in body weight) fed a commercial diet supplemented with 5.6% soybean husk showed an increase in SCFA, such as acetate and butyrate, and lactate, and a decrease in indole and skatole in the feces compared to those fed a 5.6% cellulose diet. Real-time PCR assay showed that soybean husk supplementation stimulated the growth of lactobacilli, Clostridium cluster IV including Faecalibacterium prausnitzii, Clostridium cluster XIVa, Bacteroides-Prevotella-Porphyromonas group but inhibited the growth of Clostridium cluster XI. Both in vitro and in vivo experiments indicated that soybean husk supplementation improves gastrointestinal health through optimization of beneficial organic acid production and increase of beneficial bacteria. Therefore, soybean husk is suggested to be applicable as a functional fiber in the formulation of canine diets. © 2017 Japanese Society of Animal Science.

  12. Characterisation of Pomegranate-Husk Polyphenols and Semi-Preparative Fractionation of Punicalagin.

    Science.gov (United States)

    Aguilar-Zárate, Pedro; Wong-Paz, Jorge E; Michel, Mariela; Buenrostro-Figueroa, Juan; Díaz, Hugo R; Ascacio, Juan A; Contreras-Esquivel, Juan C; Gutiérrez-Sánchez, Gerardo; Aguilar, Cristóbal N

    2017-09-01

    Pomegranate-husk is the main by-product generated from the pomegranate industry. It is a potential source of compounds highly appreciated by different costumers. Punicalagin is the main compound present in pomegranate-husk. To characterise the pomegranate-husk total polyphenols by HPLC-ESI-MS and to establish a method for the recovery of punicalagin using a medium pressure liquid chromatography (MPLC) system. The characterisation of total pomegranate-husk polyphenols was carried out using liquid chromatography coupled to mass spectrometry. Thus, 200 mg of pomegranate-husk polyphenols were fractionated by MPLC. The isolated punicalagin was characterised by HPLC-MS and was tested as standard reagent for the measurement of its scavenging capacity reducing DPPH and ABTS radicals. Twenty peaks were identified by analytical HPLC-MS analysis from the pomegranate-husk polyphenols. The main compounds were the punicalagin anomers, punicalin and ellagic acid. The MPLC method allowed three fractions to be obtained. In fraction three 39.40 ± 8.06 mg of punicalagin anomers (purity > 97.9%) were recovered. The scavenging capacity of punicalagin showed an IC 50 of 109.53 and 151.50 μg/mL for DPPH and ABTS radicals, respectively. The MPLC system was an excellent tool for the separation of the main ellagitannins from pomegranate husk and for the isolation of punicalagin anomers. Fraction three was rich in high purity punicalagin anomers. The IC 50 was obtained for DPPH and ABTS radicals. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  13. Ash Reduction of Corn Stover by Mild Hydrothermal Preprocessing

    Energy Technology Data Exchange (ETDEWEB)

    M. Toufiq Reza; Rachel Emerson; M. Helal Uddin; Garold Gresham; Charles J. Coronella

    2014-04-22

    Lignocellulosic biomass such as corn stover can contain high ash content, which may act as an inhibitor in downstream conversion processes. Most of the structural ash in biomass is located in the cross-linked structure of lignin, which is mildly reactive in basic solutions. Four organic acids (formic, oxalic, tartaric, and citric) were evaluated for effectiveness in ash reduction, with limited success. Because of sodium citrate’s chelating and basic characteristics, it is effective in ash removal. More than 75 % of structural and 85 % of whole ash was removed from the biomass by treatment with 0.1 g of sodium citrate per gram of biomass at 130 °C and 2.7 bar. FTIR, fiber analysis, and chemical analyses show that cellulose and hemicellulose were unaffected by the treatment. ICP–AES showed that all inorganics measured were reduced within the biomass feedstock, except sodium due to the addition of Na through the treatment. Sodium citrate addition to the preconversion process of corn stover is an effective way to reduced physiological ash content of the feedstock without negatively impacting carbohydrate and lignin content.

  14. Utilization of power plant bottom ash as aggregates in fiber-reinforced cellular concrete.

    Science.gov (United States)

    Lee, H K; Kim, H K; Hwang, E A

    2010-02-01

    Recently, millions tons of bottom ash wastes from thermoelectric power plants have been disposed of in landfills and coastal areas, regardless of its recycling possibility in construction fields. Fiber-reinforced cellular concrete (FRCC) of low density and of high strength may be attainable through the addition of bottom ash due to its relatively high strength. This paper focuses on evaluating the feasibility of utilizing bottom ash of thermoelectric power plant wastes as aggregates in FRCC. The flow characteristics of cement mortar with bottom ash aggregates and the effect of aggregate type and size on concrete density and compressive strength were investigated. In addition, the effects of adding steel and polypropylene fibers for improving the strength of concrete were also investigated. The results from this study suggest that bottom ash can be applied as a construction material which may not only improve the compressive strength of FRCC significantly but also reduce problems related to bottom ash waste.

  15. Magmatic and fragmentation controls on volcanic ash surface chemistry

    Science.gov (United States)

    Ayris, Paul M.; Diplas, Spyros; Damby, David E.; Hornby, Adrian J.; Cimarelli, Corrado; Delmelle, Pierre; Scheu, Bettina; Dingwell, Donald B.

    2016-04-01

    partitioning effect, but crucially, disparities between surface and bulk chemistry remain evident. Simple glass-plagioclase mixing calculations suggest that this feature may indicate differences in bulk and surface mineral distributions; future QEMSCAN analysis will investigate this possibility further. Additionally, surface iron enrichments observed in our high temperature experiments suggest that hot oxidation effects can have a near-instantaneous, measurable effect on ash surface chemistry at the nanometre scale. Our preliminary results suggest that the chemical and mineral properties of the source magma, coupled with high temperature fragmentation processes, may have a significant influence on ash surface chemistry and mineralogy, and subsequently, on the post-eruptive alteration of ash particles and their reactivity within biotic and abiotic systems.

  16. Identification of walnut husk (Juglans regia L.) volatiles and the behavioural response of the invasive Walnut Husk Fly, Rhagoletis completa Cresson.

    Science.gov (United States)

    Sarles, Landry; Boullis, Antoine; Fassotte, Bérénice; Lognay, Georges; Verhaeghe, Agnès; Francis, Frédéric; Verheggen, François J

    2017-10-01

    Several European countries are important walnut (Juglans regia L.) producers. However, these countries must contend with the recent introduction of the Walnut Husk Fly, Rhagoletis completa Cresson (Diptera, Tephritidae), which is causing severe economic losses, especially in organic production. Because most Tephritid fruit flies use kairomones in their search for host plants, we hypothesise that this highly specialist species orients toward the volatile blend released by walnut husks. We collected, identified, and quantified the volatile organic chemicals (VOCs) released by walnut husks from the most commonly cultivated variety in France (Franquette). Then, the behavioural response of R. completa toward synthetic odour blends was recorded in dual choice assays conducted in net cages. A total of 26 VOCs were identified, with α-pinene, β-pinene, trans-linalool, eugenol, and tetradecane representing the major constituents. In the dual choice assay, male and female R. completa were strongly attracted to synthetic blend that included most of the identified husk VOCs. When searching for a host plant, R. completa use host fruit kairomones. The potential of these semiochemicals in monitoring and management of this quarantine pest is discussed. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  17. Assessing the effects of FBC ash treatments of metal-contaminated soils using life history traits and metal bioaccumulation analysis of the earthworm Eisenia andrei

    Energy Technology Data Exchange (ETDEWEB)

    Grumiaux, F.; Demuynck, S.; Schikorski, D.; Lemiere, S.; Lepretre, A. [Universite Lille Nord de France, Villeneuve Dascq (France)

    2010-03-15

    Earthworms (Eisenia andrei) were exposed, in controlled conditions, to metal-contaminated soils previously treated in situ with two types of fluidized bed combustion ashes. Effects on this species were determined by life history traits analysis. Metal immobilizing efficiency of ashes was indicated by metal bioaccumulation. Ashes-treated soils reduced worm mortality compared to the untreated soil. However, these ashes reduced both cocoon hatching success and hatchlings numbers compared to the untreated soil. In addition, sulfo-calcical ashes reduced or delayed worm maturity and lowered cocoon production compared to silico-alumineous ones. Metal immobilizing efficiency of ashes was demonstrated for Zn, Cu and to a lesser extent Pb. Only silico-alumineous ashes reduced Cd bioaccumulation, although Cd was still bioconcentrated. Thus, although ash additions to metal-contaminated soils may help in immobilizing metals, their use might result, depending on the chemical nature of ashes, to severe detrimental effects on earthworm reproduction with possible long term consequences to populations.

  18. On the visibility of airborne volcanic ash and mineral dust

    Science.gov (United States)

    Weinzierl, B.; Sauer, D. N.; Minikin, A.; Reitebuch, O.; Dahlkötter, F.; Mayer, B. C.; Emde, C.; Tegen, I.; Gasteiger, J.; Petzold, A.; Veira, A.; Kueppers, U.; Schumann, U.

    2012-12-01

    After the eruption of the Eyjafjalla volcano (Iceland) in April 2010 which caused the most extensive restrictions of the airspace over Europe since the end of World War II, the aviation safety concept of avoiding "visible ash", i.e. volcanic ash that can be seen by the human eye, was recommended. However so far, no clear definition of "visible ash" and no relation between the visibility of an aerosol layer and related aerosol mass concentrations are available. The goal of our study is to assess whether it is possible from the pilot's perspective in flight to detect the presence of volcanic ash and to distinguish between volcanic ash and other aerosol layers just by sight. In our presentation, we focus the comparison with other aerosols on aerosol types impacting aviation: Besides volcanic ash, dust storms are known to be avoided by aircraft. We use in-situ and lidar data as well photographs taken onboard the DLR research aircraft Falcon during the Saharan Mineral Dust Experiments (SAMUM) in 2006 and 2008 and during the Eyjafjalla volcanic eruption in April/May 2010. We complement this analysis with numerical modelling, using idealized radiative transfer simulations with the 3D Monte Carlo radiative transfer code MYSTIC for a variety of selected viewing geometries. Both aerosol types, Saharan mineral dust and volcanic ash, show an enhanced coarse mode (> 1 μm) aerosol concentration, but volcanic ash aerosol additionally contains a significant number of Aitken mode particles (Volcanic ash is slightly more absorbing than mineral dust, and the spectral behaviour of the refractive index is slightly different. According to our simulations, these differences are not detectable just by human eye. Furthermore, our data show, that it is difficult to define a lower threshold for the visibility of an aerosol layer because the visual detectability depends on many parameters, including the thickness of the aerosol layer, the brightness and color contrast between the airborne

  19. Composites Prepared From Rice Husk and Recycled/Virgin HDPE with Addition of CouplingAgent

    OpenAIRE

    Mulana, Farid

    2012-01-01

    Compositesweremade from recycled HDPE and virgin HDPE as matrix and ricehusk as filler and also added with polyethylene-graft-maleic anhydride (MAPE) as a coupling agent to improve the physical and mechanical properties of composites. Theaim of study is to find the optimum condition of the type of used matrixs and the percentage of added coupling agent on the quality of the producedcomposites. Compositeswere prepared byhot press method. Hot press process was performed at a temperature of 150 ...

  20. Investigation into the morphology, composition, structure and dry tribological behavior of rice husk ceramic particles

    Science.gov (United States)

    Hu, Enzhu; Hu, Kunhong; Xu, Zeyin; Hu, Xianguo; Dearn, Karl David; Xu, Yong; Xu, Yufu; Xu, Le

    2016-03-01

    To expand the application of rice husk (RH) resource, this study developed carbon-based RH ceramic (RHC) particles using a common high-temperature carbonization method. The morphology, composition, and structure of the RHC particles were characterized with a series of modern analysis technologies and were then compared with those of the initial RH powder and carbonized RH (CRH) particles. The dry tribological behavior of RHC particle adobes (RHAs) was also investigated. Results showed the sheet-shaped morphology of the RHC particles. The graphitization degree of the RHC particles was lower than that of the CRH particles possibly because the phenolic resin (PR) filled the micro-pores of the RH particles, thereby prompting the formation of amorphous carbon in the RHC particles as a result of high-temperature carbonization. The appearance of a hydroxy function group (sbnd OH) on the surface of the RHC particles was ascribed to the decomposition of PR at 900 °C. The friction coefficients and mass loss rates of the RHAs almost increased with the rise in load and velocity. In addition, the friction coefficients of the RHAs decreased at high load (5 N) and velocity (0.261 m/s) conditions. Such outcome indicated that the variation of contact area between steel ball and RHA at high load and velocity conditions resulted in the abrasive wear or catastrophic wear.