WorldWideScience

Sample records for husk ash produced

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Utilization Of Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    S. D. Nagrale

    2012-07-01

    Full Text Available India is a major rice producing country, and the husk generated during milling is mostly used as a fuel in the boilers for processing paddy, producing energy through direct combustion and / or by gasification. About 20 million tones of Rice Husk Ash (RHA is produced annually. This RHA is a great environment threat causing damage to the land and the surrounding area in which it is dumped. Lots of ways are being thought of for disposing them by making commercial use of this RHA. RHA can be used as a replacement for concrete (15 to 25%.This paper evaluates how different contents of Rice Husk Ash added to concrete may influence its physical and mechanical properties. Sample Cubes were tested with different percentage of RHA and different w/c ratio, replacing in mass the cement. Properties like Compressive strength, Water absorption and Slump retention were evaluated.

  3. 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.

  4. Synthesis and surface characteristics of nanosilica produced from alkali-extracted rice husk ash

    Energy Technology Data Exchange (ETDEWEB)

    Liou, Tzong-Horng, E-mail: thliou@mail.mcut.edu.tw [Department of Chemical Engineering, Ming Chi University of Technology, 84 Gungjuan Rd., Taipei 24301, Taiwan (China); Yang, Chun-Chen [Department of Chemical Engineering, Ming Chi University of Technology, 84 Gungjuan Rd., Taipei 24301, Taiwan (China)

    2011-04-25

    Rice husk is a form of agricultural biomass that provides an abundant silicon source. This study used rice husk as a raw material to prepare nanosilica without adding an extra surfactant. This work investigated a dissolution-precipitation technique as a function of acid treatment, sodium silicate concentration, gelation pH, aging temperature, and aging time to establish optimum conditions for preparing silica nanoparticles. Experimental results showed that silica produced by hydrochloric acid possesses higher surface area than that of sulfuric, oxalic, and citric acids. Surface characteristics of the sample depend mainly upon gelation pH. The highest surface area and pore volume of silica samples were 634 m{sup 2}/g and 0.811 cm{sup 3}/g. Pore diameters were controllable from 3 to 9 nm by adjusting the solution pH value. Particles had a uniform size of 5-30 nm. The objective of this study was to develop a method of nanosilica preparation that enhances the economic benefits of re-using rice husk waste.

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

    African Journals Online (AJOL)

    Porcelain powder was grounded separately in a ball mill. The powder was sieved using ... The mixed powder .... combustion at 7000C produces a very good reactive material. The .... rice husk-berk ash on mechanical properties of of concrete.

  6. Mesoporous Silica from Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    V.R. Shelke

    2011-01-01

    Full Text Available Mesoporous silica is used as a raw material in several areas: in preparation of catalysts, in inks, as a concrete hardening accelerator, as a component of detergents and soaps, as a refractory constituent etc. Sodium silicate is produced by reacting rice hull ash (RHA with aqueous NaOH and silica is precipitated from the sodium silicate by acidification. In the present work, conversion of about 90% of silica contained in RHA into sodium silicate was achieved in an open system at temperatures of about 100 °C. The results showed that silica obtained from RHA is mesoporous, has a large surface area and small particle size. Rice Husk is usually mixed with coal and this mixture is used for firing boilers. The RHA therefore, usually contains carbon particles. Activated carbon embedded on silica has been prepared using the carbon already present in RHA. This carbon shows good adsorption capacity. ©2010 BCREC UNDIP. All rights reserved(Received: 25th April 2010, Revised: 17th June 2010, Accepted: 24th June 2010[How to Cite: V.R. Shelke, S.S. Bhagade, S.A. Mandavgane. (2010. Mesoporous Silica from Rice Husk Ash. Bulletin of Chemical Reaction Engineering and Catalysis, 5 (2: 63-67. doi:10.9767/bcrec.5.2.793.63-67][DOI: http://dx.doi.org/10.9767/bcrec.5.2.793.63-67

  7. 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

  8. Concrete with Highly Active Rice Husk Ash

    Institute of Scientific and Technical Information of China (English)

    FENG Qing-ge; LIN Qing-yu; YU Qi-jun; ZHAO San-ying; YANG Lu-feng; Shuichi Sugita

    2004-01-01

    The overall aim was to investigate the effect of highly active rice husk ash (RHA) produced by an industrial furnace on some properties of concrete. The strength, pore volume and pore distribution of concrete and the Ca(OH)2 content in concrete were investigated by JIS A 1108 (Method of test for compressive strength of concrete), a mercury instrument porosimeter, and the thermogravimetric analysis, respectively. The results show that,with RHA replacement of cement,the compressive strength of concrete is increased evidently;the average pore radius of concrete is greatly decreased, especially the portion of the pores greater than 20nm in radius is decreased while the amount of smaller pores is increased, and the more the RHA replacement, the less the amount of Ca(OH)2 in concrete. The latter two results are the main reasons for the strength enhancement of concrete.

  9. Rice Husk Ash Sandcrete Block as Low Cost Building Material

    Directory of Open Access Journals (Sweden)

    S.P.Sangeetha,

    2016-06-01

    Full Text Available Concrete is a widely used construction material for various types of structures due to its structural stability and strength. The construction industry is today consuming more than 400 million tonnes of concrete every year .Most of the increase in cement demand will be met by the use of supplementary cementing materials, as each ton of Portland cement clinker production is associated with similar amount of CO2 emission, which is a major source of global warming. Partial replacement of ordinary Portland cement with mineral admixtures like fly ash, ground granulated blast furnace slag, silica fume, metakaolin, Rice husk Ash (RHA,etc with plasticizers eliminates these drawbacks. The use of rice husk modifies the physical qualities of fresh cement paste as well as microstructure of paste after hardening. By burning the rice husk under a uncontrolled temperature in the atmosphere, a highly reactive RHA was obtained and the ash was utilized as a supplementary cementing material. This paper presents the effects of using Rice Husk Ash (RHA as a partial cement replacement material in mortar mixes. This work is based on an experimental study of mortar made with replacement of Ordinary Portland Cement (OPC with 10%, 20% 30% & 40% RHA. The properties investigated were the compressive strength, setting time, consistency, workability and specific gravity. Finally, a cost analysis was also done to compare the efficiency of rice husk ash sandcrete blocks. From the test results it can be concluded that rice husk ash can be utilized in day today life of manufacturing building blocks which are more economical and more eco-friendly than the cement concrete blocks which are produced now-a-days.

  10. Effect of grinding on chemical and physical properties of rice husk ash

    Institute of Scientific and Technical Information of China (English)

    Sumrerng Rukzon; Prinya Chindaprasirt; Rattana Mahachai

    2009-01-01

    The effect of grinding on the chemical and physical properties of rice husk ash was studied.Four rice husk ashes with dif-ferent finenesses, i.e.coarse original rice husk ash (RHA0), RHAI, RHA2, and RHA3 were used for the study.Ordinary Portland cement (OPC) was partially replaced with rice husk ash at 20% by weight of binder.The water to binder ratio (W/B) of the mortar was maintained at 110%±5% with flow table test.Specific gravity, fineness, chemical properties, compressive strength, and porosity test of mortars were determined.The differences in chemical composition of the rice husk ashes with different finenesses from the same batch are small.The use of RHA3 produces the mortars with good strength and low porosity.The strength of the mortar im-proves with partial replacement of RHA3 in comparison with normal coarse rice husk ash.The use of RHA3 results in a strong anddense mortar, which is due to the better dispersion and filling effect, as well as an increase in the pozzolanic reaction.

  11. Radon resistant potential of concrete manufactured using Ordinary Portland Cement blended with rice husk ash

    Science.gov (United States)

    Chauhan, R. P.; Kumar, Amit

    2013-12-01

    The emission of radon from building materials and soil depends upon the radium content, porosity, moisture content and radon diffusion length of materials. Several techniques have been used to reduce the radon emission from the soil using different flooring materials. But the effectiveness of radon shielding depends upon the diffusion of radon through these materials. The present study proposes a method for producing a radon resistant material for decreasing radon diffusion through it. The method involves rice husk ash (RHA) in addition to cement for the preparation of concrete used for flooring and walls. The radon diffusion, exhalation and mechanical property of concrete prepared by rice husk ash blended cement were studied. The addition of RHA caused the reduction in radon diffusion coefficient, exhalation rates, porosity and enhanced the compressive strength of concrete. The bulk radon diffusion coefficient of cementitious concrete was reduced upto 69% by addition of rice husk ash as compare to that of control concrete.

  12. Properties of Rice Husk Ash Stabilized Laterite Roof Tiles

    Directory of Open Access Journals (Sweden)

    Momoh Omuya RAHEEM

    2013-11-01

    Full Text Available This paper presents the results of work on the possibility of using of Rice Husk Ash (RHA in the production of clay roof tiles. The pozzolana content of the ash was determined using X-Ray Fluorescence (XRF to confirm the key elements of RHA as a good pozzolanic material. The tiles were produced by moulding clay-RHA blends of various proportions of RHA used in wooden moulds. The percentages by weight of RHA added to various mixes were 0, 5, 10, 15, 20, 25 and 30% RHA and the tiles were fired at 900°C, 1000°C and 1100°C in an electric furnace. The water absorption, density, permeability and Transverse Breaking Stress (TBS of the roof tile produced were tested using manual TBS testing apparatus and weighing balances. The relative trends of the properties tested were dependent on pozzolanic property of RHA and since the sum of the active pozzolanas - SiO2, Al2O3 and Fe2O3 present in the ash is 86.01% and meets 70% minimum recommend by ASTM C618-92a for Class F pozzolana. Most optimal results were obtained at 15% RHA and 900°C temperature for water absorption, density, permeability and Transverse Breaking Stress (TBS.

  13. Developing high-performance concrete incorporating highly-reactive rice husk ash

    Directory of Open Access Journals (Sweden)

    Andrés Salas

    2012-10-01

    Full Text Available The aim of this study is to present results of an investigation about the developing of a highperformance concrete (HPC using a highly reactive pozzolan made from chemically treated rice husk ash (ChRHA prepared by a chemical-thermal attack to the rice husk. This particular rice husk ash (RHA consists of 99% of silica, highly amorphous, white in color and of greater pozzolanic activity than the silica fume and another rice husk ash prepared with only by a thermal treatment. The results of the physical, chemical and mineralogical characteristics of ChRHA are analyzed. In this study, the compressive strength, flexural strength, water absorption, resistance to carbonation, total charge-passed derived from rapid chloride permeability test (RCPT and modulus of elasticity of hardened concrete were determined in the laboratory. Test results indicate that it is possible to produce HPC with the incorporation the chemically treated RHA. The incorporation of the chemically treated rice husk ash into the concrete enhances the compressive strengthand the durability properties being comparable to the properties of high performance concretes with silica fume (SF made with the same replacement levels.

  14. Synthesis and characterization of geopolymer from bottom ash and rice husk ash

    Science.gov (United States)

    Anggarini, Ufafa; Sukmana, Ndaru C.

    2016-02-01

    All Geopolymer (GP) has been synthesized from bottom ash and rice husk ash. This research aims to determine the effect of Si/Al ratio on geopolymer synthesis. Geopolymer was synthesized with various Si/Al ratio of 2, 3 and 4. The characterization result using XRD and SEM indicated that by using a different ratio of Si/A, it will produce geopolymer with varied structure and morphology. Diffractogram result shows that polymerization has been done for all samples (GP2, GP3, Gp4) with the presence of hump peak at 2θ = 27-35°. In GP4, no peak at 2θ = 18° indicating sodalite phase forming. Besides that, the morphology of geopolymer with a varied ratio of Si/Al shows that higher ratio will produce geopolymer with higher particle size. The highest compressive strength of geopolymer was obtained at a ratio of Si/Al = 4, with a maximum load of 12866 kgf.

  15. 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.

  16. 具有高比表面积的稻壳灰的制备及其化学活性的研究%Study on Preparation of Rice Husk Ash with High Specific Surface Area and Its Chemical Reactivity

    Institute of Scientific and Technical Information of China (English)

    冯庆革; 林清宇; 童张法; S.Sugita

    2004-01-01

    Preparation of rice husk ash with high specific surface area and chemical reactivity of the product are reported in this paper. The amorphous rice husk ash with high specific surface area of 311 m2·g-1 was produced by heating acid treated rice husk at 700℃ for 4 h. The isotherms of rice husk ash are similar in shape to type Ⅱof Brunaner's classification with mesopores being predominant. The rice husk ash has a high chemical reactivity,especially that pretreated with acid. This chemical reactivity depends on ashing temperature and pretreatment conditions. There is an exponential relation between the specific surface area of rice husk ash and the change in the conductivity of saturated Ca(OH)2 solution with rice husk ash, from which the specific surface area can be known according to the conductivity change.

  17. 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.

  18. 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.

  19. Use of Rice Husk Ash as Partial Replacement with Cement In Concrete- A Review

    Directory of Open Access Journals (Sweden)

    Sourav Ghosal,

    2015-09-01

    Full Text Available Rapid increase in construction activities has resulted in shortage of conventional construction materials.In the present scenario, the high cost of conventional building materials is a major factor affecting housing delivery in the world.This has necessitated research into alternative materials of construction.The effective housing techniques deal with reduction in cost of construction as well as providing strength to buildings.Mainly gravel,sand and cement are used in the preparation of conventional concrete.While the use of agricultural by-product i.e. rice husk as a partial replacement with the conventional fine aggregates is expected to serve the purpose of encouraging housing developers in building construction.Rice husk is produced in about 100 million tons per annum in India. Twenty kg of rice husk are obtained from 100 kg of rice.It contains organic substances and 20% inorganic material.Ash from rice is obtained as a result of combustion of rice husk at suitable temperature. Proper utilization of it aims to save the environment,encourages the Government to find solutions regarding disposal to land fills of waste materials,and provides new knowledge to the contractors and developers on how to improve the construction industry by using rice husk, to sustain good product performance and to meet recycling goals.The rice husk ash concrete aims to prepare light weight structural concrete which may reduce considerably the self load of structures and permits large precast units to be handled.The main objective is therefore to encourage the use of these ‘seemingly’ waste products as construction materials in low cost housing.The various basic properties of rice husk concrete are reviewed in this paper.

  20. 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...

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

    OpenAIRE

    SUYITNO; SANURYA PUTRI PURBANINGRUM; DOMINICUS DANARDONO; ALFAITORY EMHEMED SALEM; FATHI A. MANSUR

    2015-01-01

    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 ...

  2. 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.

  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. 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. 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.

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

    Directory of Open Access Journals (Sweden)

    Pinar Terzioglu

    2012-11-01

    Full Text Available 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 MgCl2 • 6H2O, temperature (25 °C or 50 °C, and the washing agent (water and acetone on the chemical composition and surface characteristics of magnesium silicate. The results demonstrated that all of the variables affected the surface characteristics of magnesium silicate, such as surface area, particle size, and pore volume. However, it was also observed that the studied parameters did not affect the chemical composition of magnesium silicate. The wheat husk ash-based magnesium silicates obtained in the experimental study had a BET surface area ranging from 79 to 91 m2/g and a particle size varying from 42 to 63 µm.

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

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shu-Ting; Yan, Kang-kang; Zhang, Yuan hu; Jin, Shi-di; Ye, Ying; Chen, Xue-Gang, E-mail: chenxg83@zju.edu.cn

    2015-11-15

    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. - Highlights: • RN400–800 samples are potential light-weight electromagnetic absorbers. • Carbon and SiC are considered as dominating contributions for the dielectric loss. • Magnesiumothermic reduction extends the EM wave absorption potential of RHN.

  8. Properties of Rice Husk Ash (RHA and MIRHA Mortars

    Directory of Open Access Journals (Sweden)

    Narayanan Sambu Potty

    2014-05-01

    Full Text Available Rice husk Ash (produced by traditional burning called RHA and by using microwave incinerator called MIRHA has shown promise as a cement replacement material. This study investigated the properties of RHA and MIRHA mortar used for brick manufacture at binder sand proportions of 1:3 and 1:4. RHA and MIRHA were intermediate in particle size to cement and sand particles. Percentages of replacement were 5, 10, 15, 20, 25 and 30%, respectively. Strength at w/c ratios (0.5, 0.55, 0.6 and 0.65, respectively was investigated to identify optimum w/c ratios as well as optimum percent replacement of RHA and MIRHA. Variations of IRS, density and water absorption were investigated. Generally 1:3 RHA and 1:3 MIRHA mortars strength showed decreasing trend with increasing percentage replacement with RHA and MIRHA. Whereas 1:4 RHA and 1:4 MIRHA mortars showed increase in strength at 5% replacement and decrease thereafter. IRS values for RHA mortars are generally within limits (0.25-1.5 kg/m2.min recommended. Water absorption values of RHA mortars are generally higher than control mortar. IRS values for MIRHA mortars with w/c 0.5 and 0.55 ranged between 1.4-2.0 kg/m2 .min; indicating the need for wetting the bricks before use. IRS values for 1:3 MIRHA mortars with w/c 0.6 and 0.65 were below 1.0 kg/m2.min indicating low suction values. For 1:4 MIRHA mortars, IRS values were very low in all cases. Water absorption values of MIRHA mortars are generally higher than the control mortar. MIRHA mortars with w/c 0.6 and 0.65 showed low percentages of water absorption.

  9. 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.

  10. Strength of Ternary Blended Cement Sandcrete Containing Afikpo Rice Husk Ash and Saw Dust Ash

    Directory of Open Access Journals (Sweden)

    L. O. Ettu

    2013-01-01

    Full Text Available This work investigated the compressive strength of ternary blended cement sandcrete containing Afikpo rice husk ash (RHA and sawdust ash (SDA. 105 sandcrete cubes of 150mm x 150mm x 150mm were produced with OPC-RHA binary blended cement, 105 with OPC-SDA binary blended cement, and 105 with OPC-RHA-SDA ternary blended cement, each at percentage OPC replacement with pozzolan of 5%, 10%, 15%, 20%, and 25%. Three cubes for each percentage replacement of OPC with pozzolan and the control were tested for saturated surface dry bulk density and crushed to obtain their compressive strengths at 3, 7, 14, 21, 28, 50, and 90 days of curing. The 90-day strengths obtained from ternary blending of OPC with equal proportions of RHA and SDA were 11.80N/mm2for 5% replacement, 11.20N/mm2for 10% replacement, 10.60N/mm2for 15% replacement, 10.00N/mm2for 20% replacement, and 9.10N/mm2for 25% replacement, while that of the control was 10.90N/mm2. This suggests that very high sandcrete strength values could be obtained with OPCRHA-SDA ternary blended cement with richer mixes, high quality control, and longer days of hydration. Thus, OPC-RHA-SDA ternary blended cement sandcrete could be used for various civil engineering and building works, especially where early strength is not a major requirement.

  11. Studies on Concrete Characteristic Strength Using Fly Ash And Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    Khusbu Rajhans

    2014-02-01

    Full Text Available Through out the world, the most widely used construction material is concrete, commonly made by mixing Portland cement with sand, crushed rock, and water. As concrete is being widely used for the construction of most of the buildings, bridges etc, it has been labelled as the backbone to the infrastructure development of a nation. Currently our country is doing major work to improve and develop its infrastructure by constructing industrial and commercial projects and National Highways which creats major economic problem. At present about 120 million ton of cement is being produced in India every year. That much amount of cement is expected to reach close to 470 million ton by 2017[3].Though the production of cement is at comfortable level to meet, the rapidly increasing cost of production of cement is a matter of concern. Hence, currently the entire construction industry is in search of suitable and effective the waste product that would considerably minimize the use of cement and ultimately reduce the construction cost. Few of such products have already been identified like Rice Husk Ash (RHA, Fly Ash(FA, Silica Fume etc. Amongst them RHA is known to have good prospects in minimizing the usage of cement.

  12. 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.

  13. 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.

  14. Rice husk ash as corrective of soil acidity

    Directory of Open Access Journals (Sweden)

    Gláucia Oliveira Islabão

    2014-06-01

    Full Text Available Rice husk ash (RHA is a by-product from the burning of rice husk that can have favorable effects on the soil in terms of acidity correction. The objectives of this study were to determine the effective calcium carbonate equivalent (ECC of RHA under field conditions, and establish technical criteria as a basis for estimating the overall ECC of RHA. The 12 treatments of the experiment consisted of 10 RHA dosages (0, 10, 20, 30, 40, 60, 80, 100, 120, and 140 Mg ha-1 and two references, one of which was an absolute control (AC and the other a plot limed and fertilized according to official recommendations (recommended fertilization - RF. The soil was sampled twice (15 and 210 days after incorporating RHA, in the layers 0.00-0.10 and 0.10-0.20 m, to determine the pH(H2O and base saturation (V%. The ECC and neutralizing value (NV of RHA were also determined. The results showed that RHA neutralizes soil acidity, in a faster reaction than conventional limestone, despite a low ECC (around 3 %.

  15. Effect of Rice Husk Ash on Cement Stabilized Laterite

    Directory of Open Access Journals (Sweden)

    Musa ALHASSAN

    2007-09-01

    Full Text Available Laterite soil collected from Maikunkele area of Minna, classified as an A-7-6 on AASHTO classification, was stabilized with 2-8% cement by weight of the dry soil. Using British Standard Light (BSL compaction energy, the effect of Rice Husk Ash (RHA on the soil was investigated with respect to compaction characteristics, California Bearing Ratio (CBR and Unconfined Compressive Strength (UCS tests. Results obtained, indicate a general decrease in Maximum Dry Density (MDD and increase in Optimum Moisture Content (OMC, all with increase in RHA Content (2-8% at specified cement contents. There was also a tremendous improvement in the CBR and UCS with increase in the RHA content at specified cement contents to their peak values at between 4-6% RHA. The UCS values also improved with curing age. This indicates the potentials of using 4-6% RHA admixed with less cement contents for laterite soil stabilization.

  16. effects of variability in the pozzolanic properties of rice husk ash on ...

    African Journals Online (AJOL)

    user

    Keywords: Compressive Strength, Concrete, Rice Husk Ash (RHA), ... When the material is mixed with lime in powdered .... that it was free from deleterious materials as required .... Properties and Drying Shrinkage”, Australian Journal of.

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

    African Journals Online (AJOL)

    hp

    The study is an investigation into the effect of rice husk ash (RHA) on some geotechnical properties of a ... Optimum Moisture Content (OMC), California Bearing Ratio (CBR) and Consistency indices. ... RHA used as overall binder system for.

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

    OpenAIRE

    Jan-Jezreel F. Saceda; Leon,Rizalinda L. de; Kamolwan Rintramee; Sanchai Prayoonpokarach; Jatuporn Wittayakun

    2011-01-01

    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 prod...

  19. 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.

  20. 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.

  1. Utilization of Rice Husk Ash for Sustainable Construction: A Review

    Directory of Open Access Journals (Sweden)

    M.N.N. Khan

    2015-04-01

    Full Text Available Applications of Supplementary Cementitious Materials (SCM in construction industry are getting priority due to environmental friendly behavior as well as enhanced mechanical and durability properties. Considering the characteristics of SCM, properly burnt and ground Rice Husk Ash (RHA has significant potential on account of rich reactive silica (SiO2 compound. When RHA is applied in cementitious system it improves the systems properties by two fold of effects; chemical or pozzlanic effect and physical or filler effect. The reactive silica compound present in RHA reacts with cement hydration products calcium hydroxide (Ca (OH2 and formed secondary C-S-H gel, which is counted as chemical or pozzolanic activity of RHA. The physical or filler effect of RHA is denoted as the proper distribution of finer RHA particles into the cementitious system. This study reviews the advantageous use of RHA for sustainable construction. The aim of this study is to promote the idea of using RHA by elaborating upon their various production processes, different properties, pozzolanic activity and its contribution to the cementitious system.

  2. Durability of Concrete Using Rice Husk Ash as Cement Substitution Exposed To Acid Rain

    Directory of Open Access Journals (Sweden)

    I. A. Ahmad

    2014-05-01

    Full Text Available The acidity of rainfall in major areas of Indonesia is under neutral pH. Average pH of rainfall is between 3 and 5. Free lime within concrete will react with acid and cause a decrease in the strength of concrete. A means to anticipate the damage is to reduce the content of free lime within concrete. Silicon oxide contained in rice husk ash can react with free lime to form a new compound that is harder and denser. It became the basis for the use of rice husk ash in concrete mixtures. The mixtures were prepared by replacing 5% and 10% of cement with rice husk ash and the results were compared with a reference mix with 100% cement. This paper presents the results of an experimental investigation on the mechanical characteristics of concrete specimens as durability parameters. Then to evaluate the mechanical characteristics, microstructure test was conducted. The lower the mechanical properties of the concrete, the higher the level of gypsum contained within concrete. The percentage of 5% rice husk ash of the cement weight has a lower compressive strength decrease than the 10% rice husk ash. In addition, the proposed durability model is a model of polynomial equation with two variables.

  3. Synergic Effect of Wheat Straw Ash and Rice-Husk Ash on Strength Properties of Mortar

    Science.gov (United States)

    Goyal, Ajay; Kunio, Hattori; Ogata, Hidehiko; Garg, Monika; Anwar, A. M.; Ashraf, M.; Mandula

    Pozzolan materials obtained from various sources; when used as partial replacement for Portland cement in cement based applications play an important role not only towards sustainable development but in reducing the construction costs as well. Present study was conducted to investigate the synergic effect of Rice-Husk Ash (RHA) and Wheat Straw Ash (WSA) on the strength properties of ash substituted mortar. Ash materials were obtained after burning the wastes at 600°C for 5 h at a control rate of 2°C min. Two binary blends of mortar substituting 15% cement with WSA and RHA and three combinations of ternary blend with (10+5)%, (5+10)% and (7.5+7.5)% mix ratios of WSA and RHA, together with a control specimen were subjected to destructive (compressive and flexural strength) as well as non-destructive (ultrasonic pulse velocity) tests till 180 days of curing. Ternary blend with (7.5 + 7.5)% combination of WSA and RHA showed better strength results than control and other blends and proved to be the optimum combination for achieving maximum synergic effect.

  4. Synthesis of ZSM-5 zeolite from lignite fly ash and rice husk ash

    Energy Technology Data Exchange (ETDEWEB)

    Chareonpanich, Metta; Namto, Teerapong; Kongkachuichay, Paisan [Department of Chemical Engineering, Kasetsart University, 50 Paholyothin Rd., Chatuchak, Bangkok 10900 (Thailand); Limtrakul, Jumras [Department of Chemistry, Kasetsart University, Chatuchak, Bangkok 10900 (Thailand)

    2004-10-15

    The lignite fly ash from the Mae-Moh power plant, Thailand, and rice husk ash were used as raw materials for ZSM-5 zeolite synthesis. Factors affecting the yield of ZSM-5 zeolite synthesized from fly ash, i.e., the SiO{sub 2}/Al{sub 2}O{sub 3} mole ratio, the presence of tetrapropyl ammonium bromide (TPABr, the structure-directing material for ZSM-5 zeolite synthesis), the holding temperature and time, and the initial pressure were investigated. It was found that without TPABr only zeolite P could be synthesized at SiO{sub 2}/Al{sub 2}O{sub 3} mole ratios of 2.8-200. In order to synthesize ZSM-5 zeolite, sodium silicate solution was added to adjust the SiO{sub 2}/Al{sub 2}O{sub 3} mole ratio in raw ash. The yield of ZSM-5 zeolite was as high as 59 wt.% when following conditions were used: SiO{sub 2}/Al{sub 2}O{sub 3} mole ratio, 40; the holding temperature, 210 C; the holding time, 4 h and the initial pressure, 4 bar. The catalytic performance for CO{sub 2} hydrogenation reaction of the ZSM-5 zeolite was preliminary tested and compared with that of commercial one. It was observed that there was no significant difference in the catalytic performance between these two catalysts.

  5. Performance Evaluation of Steel Fibres in Rice Husk Ash Substituted Concretes

    Directory of Open Access Journals (Sweden)

    A. Sivakumar

    2013-12-01

    Full Text Available The potential use of supplementary cementitious materials in plain cement concrete for improving concrete properties has been a growing concern in recent years. In addition, the effective strengthening of the matrix by fibre reinforcements to avoid brittle failure is another requirement for plain concrete. This provided the motivation for exploring the benefits of rice husk ash (RHA as a cement replacement material and the addition of steel fibres for reducing brittleness in concrete. The rice husk ash used in this study was the residue of burnt raw rice husk sintered in a muffle furnace at 800 °C. The fine particle size of the rice husk ash provided an early pozzolanic reaction upon cement hydration and thus resulted in high cementing efficiency. This paper reports a systematic evaluation of the mechanical properties of rice husk ash substituted concrete mixtures containing RHA as a partial cement substitute at replacement levels of 10% and 20% by weight of cement, with different dosages of steel fibres. Our experimental results demonstrated that 10% RHA substitution led to improved compressive properties compared to plain concrete. The highest increase of split tensile and flexural strength was reported in the case of RHA substituted concrete with steel fibre added.

  6. 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.

  7. Pozzolanic Characterization Of Waste Rice Husk Ash (RHA) From Muar, Malaysia

    Science.gov (United States)

    Hadipramana, J.; Riza, F. V.; Rahman, I. A.; Loon, L. Y.; Adnan, S. H.; Zaidi, A. M. A.

    2016-11-01

    Investigation of Rice Husk Ash (RHA) thoroughly under controlled burning is regular issue to obtain result to produce the amorphous silica that has high pozzolanic reactivity characteristic. This paper offered an observation about characteristic of ground and un-ground of un-controlled burning temperature RHA that were taken from rice millings in Muar, Johor Malaysia. Such tests as X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), Particle Size Analysis and Specific Area Surface, Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron microscope (SEM) were conducted in this investigation to carry out the characteristic of RHA samples. The results show that the RHA was consist approximately 89.90% of silica and the RHA possessed the amorphous particle were dominant than its crystalline part. This proves that the RHA has a big potential as a pozzolanic material considering the silica content and porous structure. In addition, particle size analysis decides whether the pozzolanic reactivity can be increased by grinding process.

  8. 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.

  9. Removal of elemental mercury by iodine-modified rice husk ash sorbents

    Institute of Scientific and Technical Information of China (English)

    Pengfei Zhao; Xin Guo; Chuguang Zheng

    2010-01-01

    Iodine-modified calcium-based rice husk ash sorbents (I2/CaO/RHA) were synthesized and characterized by X-ray diffraction,X-ray fluorescence,and N2 isotherm adsorpdon/desorption.Adsorption experiments of vapor-phase elemental mercury (Hg0) were performed in a laboratory-scale fixed-bed reactor.I2/CaO/RHA performances on Hg0 adsorption were compared with those of modified Cabased fly ash sorbents (I2/CaO/FA) and modified fly ash sorbents (I2/FA).Effects of oxidant loading,supports,pore size distribution,iodine impregnation modes,and temperature were investigated as well to understand the mechanism in capturing Hg0.The modified sorbents exhibited reasonable efficiency for Hg0 removal under simulated flue gas.The surface area,pore size distribution,and iodine impregnation modes of the sorbents did not produce a strong effect on Hg0 capture efficiency,while fair correlation was observed between Hg0 uptake capacity and iodine concentration.Therefore,the content of I2 impregnated on the sorbents was identified as the most important factor influencing the capacity of these sorbents for Hg0 uptake.Increasing temperature in the range of 80-140℃ caused a rise in Hg0 removal.A reaction mechanism that may explain the experimental results was presumed based on the characterizations and adsorption study.

  10. Engineering Properties of an Expansive soil Stabilized with Rice husk ash and Lime sludge

    Directory of Open Access Journals (Sweden)

    Akshaya Kumar Sabat

    2014-01-01

    Full Text Available Compaction properties, California bearing ratio, shear strength parameters, compression index, swelling pressure and durability of an expansive soil stabilized with rice husk ash and lime sludge have been discussed in this paper. The effects of 7 and 28 days of curing on these properties except the compaction properties have also been discussed.

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

    African Journals Online (AJOL)

    user

    2016-07-03

    Jul 3, 2016 ... utilization of these wastes for beneficial engineering purposes has prompt an ... reported that rice-husk ash have thermal conductivity of 0.065 Wm-1k-1. ..... Related to its Industrial Application”, Journal of. Material Science, Vol ...

  12. Binderless board and moulded products produced from whole coconut husks

    NARCIS (Netherlands)

    Dam, van J.E.G.; Snijder, M.H.B.

    2002-01-01

    A simple and efficient technology has been developed to produce high strength - high density board materials from whole coconut husks, without the addition of chemical binders. The board material has been shown to exhibit excellent properties, which are comparable with or even superior to commercial

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

    OpenAIRE

    Mohammed Sabah Ali; M.A. Azmah Hanim; S. M. Tahir; C. N.A. Jaafar; Norkhairunnisa Mazlan; Khamirul Amin Matori

    2017-01-01

    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 res...

  14. Malaysian Rice Husk Ash – Improving the Durability and Corrosion Resistance of Concrete: Pre-review

    Directory of Open Access Journals (Sweden)

    Hamidi Abdulaziz

    2010-03-01

    Full Text Available

    The objective of this paper is to presents and study a pre-review of Malaysian rice ash ask as a partial cement replacement in different percentage, grinding time and performance corrosion of RHA blended concrete. The increasing demand for producing durable

  15. 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.

  16. Study on concrete with partial replacement of cement by rice husk ash

    Science.gov (United States)

    Kaarthik Krishna, N.; Sandeep, S.; Mini, K. M.

    2016-09-01

    Increase in the demand of conventional construction materials and the need for providing a sustainable growth in the construction field has prompted the designers and developers to opt for ‘alternative materials’ feasible for use in construction. For this objective, the use of industrial waste products and agricultural byproducts are very constructive. These industrial wastes and agricultural by products such as Fly Ash, Rice Husk Ash, Silica Fume, and Slag can be replaced instead of cement because of their pozzolanic behavior, which otherwise requires large tract of lands for dumping. In the present investigation, Rice Husk Ash has been used as an admixture to cement in concrete and its properties has been studied. An attempt was also done to examine the strength and workability parameters of concrete. For normal concrete, mix design is done based on Indian Standard (IS) method and taking this as reference, mix design has been made for replacement of Rice Husk Ash. Four different replacement levels namely 5%, 10%, 15% and 20% are selected and studied with respect to the replacement method.

  17. 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

  18. Synthesis of A type zeolite from rice husk ash; Momigarabai kara no A gata zeolite no gosei

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, K. [Kyushu National Industrial Research Institute, Saga (Japan); Hara, N. [Kagoshima Prefectural Industrial Technology Center, Kagoshima (Japan)

    1995-09-01

    Attempts have been made on synthesizing A-type zeolite from rice husk ash made from burning under different conditions. The rice husk ash (comprising SiO2 at 90 and odd percent) was obtained by heating the rice husk to remove volatile constituents, burning at 350{degree}C to reduce carbon content, and further burning at 400 to 900{degree}C. Soda aluminate and caustic soda were used as additional materials for zeolite. Zeolite was synthesized by so mixing the raw materials that predetermined composition is achieved, adding seed crystals, and heating at 90{degree}C. The result may be summarized as follows: raising the burning temperature reduces the carbon content and increases whiteness of the rice husk ash; dissolution velocity of rice husk ash into NaOH aqueous solution was measured to evaluate the reactivity of the ash (the higher the more preferable); raised burning temperature causes transfer from amorphous state to crystalline state, reducing the dissolution velocity; the lower the burning temperature, the higher the A-type zeolite production rate becomes; whiteness in zeolite is insufficient; preparing water glass from rice husk ash and synthesizing zeolite therefrom achieves high whiteness and high production rate. 6 refs., 4 figs., 2 tabs.

  19. 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.

  20. Hydrothermal and mechanochemical reactions of rice husk ash with calcium hydroxide

    Energy Technology Data Exchange (ETDEWEB)

    Sugita, S.; Isojima, Y. [Hachinohe Institute of Technology, Aomori (Japan); Yu, Q. [Wuhan University of Technology, (Taiwan, Province of China)

    1998-05-01

    It is well known that a calcium silicate hydrate, commonly referred to as C-S-H gel, is important for cement to exhibit strength. Silica is present in rice husk ash to around 90%. When sufficiently sintered and crushed, rice husk ash mostly comprises amorphous silica having a large surface area. It is reactive, and is considered to contribute to improvement of concrete strength and durability. In this study, rice husk ash is reacted with calcium hydroxide under hydrothermal conditions or mechanochemical conditions at normal temperature, to synthesize Ca(1.5)SiO(3.5){center_dot}xH2O as one of the calcium silicate hydrates. It has an average particle size of 10{mu}m or smaller, which varies depending on synthesis method and condition. The compound synthesized at 40degC is composed of flocs having a porous structure and large specific surface area, as is the case with a C-S-H gel present in Portland cement paste. It loses the above structure and moisture in the fine pores gradually, when heated, but remains amorphous at up to 750degC. It is transformed into wollastonite, when heated to 780degC. 7 refs., 8 figs., 3 tabs.

  1. 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).

  2. 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.

  3. 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.

  4. 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.

  5. Synthesis of ZSM-5 zeolite using silica from rice husk ash

    Energy Technology Data Exchange (ETDEWEB)

    Rawtani, A.V.; Rao, M.S. (Dept. of Chemical Engineering, Indian Institute of Technology, Kanpur 208 016 (IN)); Gokhale, K.V.G.K. (Dept. of Civil Engineering, Indian Institute of Technology, Kanpur 208 016 (IN))

    1989-09-01

    The authors describe ZSM-5 zeolite synthesized from the Na-TPA cation system for the first time using silica from rice husk ash. In this study, rice husk ash was the only source of silica and alumina used in the synthesis. The molar ratio of SiO/sub 2//Al/sub 2/O/sub 3/ in the husk was 24.88, which was constant throughout. The synthesis has been carried out for temperatures ranging from 125 to 200{sup 0}C and durations of synthesis has from 6 to 120 h with Na/sub 2/O/Al/sub 2/O/sub 3/ and H/sub 2/O/Al/sub 2/O/sub 3/ molar ratios ranging from 3.25 to 15.15 and 1081 to 2786, respectively. The effects of varying the composition of initial mixture, the alkalinity, and the time on synthesis were studied. The product at each stage has been characterized by using X-ray diffraction analysis, infrared spectroscopy, differential scanning calorimetry, and electron microscopy.

  6. 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.

  7. Novel uses of rice-husk-ash (a natural silica-carbon matrix) in low-cost water purification applications

    Science.gov (United States)

    Malhotra, Chetan; Patil, Rajshree; Kausley, Shankar; Ahmad, Dilshad

    2013-06-01

    Rice-husk-ash is used as the base material for developing novel compositions to deal with the challenge of purifying drinking water in low-income households in India. For example, rice-husk-ash cast in a matrix of cement and pebbles can be formed into a filtration bed which can trap up to 95% of turbidity and bacteria present in water. This innovation was proliferated in villages across India as a do-it-yourself rural water filter. Another innovation involves embedding silver nanoparticles within the rice husk ash matrix to create a bactericidal filtration bed which has now been commercialized in India as a low-cost for-profit household water purifier. Other innovations include the impregnation of rice-husk-ash with iron hydroxide for the removal of arsenic from water and the impregnation of rice-husk ash with aluminum hydroxide for the removal of fluoride ions from water which together have the potential to benefit over 100 million people across India who are suffering from the health effects of drinking groundwater contaminated with arsenic and fluoride.

  8. Study of peanut husk ashes properties to promote its use as supplementary material in cement mortars

    Directory of Open Access Journals (Sweden)

    J. Kreiker

    Full Text Available The properties of peanut husk ashes as a potential supplementary material in cement mortars were studied in the laboratory. The ashes were prepared in an electric furnace at 500, 650 and 800 ºC during 180 minutes and used without further treatment. The characterization of ashes includes X-Ray fluorescence, X-Ray diffraction, SEM, and determination of pozzolanic activity by conductivity. The ashes were tested in mortars as partial substitute of Portland cement, in a rate of 15 % of substitution. The compression strength of mortars was evaluated between 7 and 120 days, for probes prepared using a proportion of cement:sand of 1:3 on weight with water/cement ratio of 0,5 v/v. It was observed that the calcinations conditions influenced the behavior of the ashes, giving better results the ashes obtained at 500 ºC. The compression tests showed values near to 70% at 7 days but higher than 80% after 28 days for mortars prepared with ashes, respect to the cement mortar reference.

  9. 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.

  10. 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)

  11. 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.

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

    OpenAIRE

    Lizandro Ciciliano Tavares; André Pich Brunes; Daniel Andrei Robe da Fonseca; Gizele Ingrid Gadotti; Lilian Madruga de Tunes; Géri Eduardo Meneghello; Antonio Carlos Souza Albuquerque Barros

    2013-01-01

    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,...

  13. 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.

  14. 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.

  15. Research on the Adsorption of Methylene Blue with Rice Husk Ash Aided by Ion Beam Etching Technique

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the mechanism of the removal effect of methylene blue(MB) by rice husk ash(RHA).[Method] The effects of contact time and pH on the adsorption of MB by rice husk ash were investigated,and the mechanism was discussed.[Result] RHA exhibited a remarkable ability on the adsorption of MB.The process of adsorption reached the equilibrium after 30 min,at about pH 9.The adsorption effect was explored with the aid of ion beam etching technique,which displayed that there were two main ...

  16. 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.

  17. 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.

  18. Mechanical Behavior of Concrete Modified by Replacement of Cement by Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    M.M. Saravanan

    Full Text Available ABSTRACT Construction industry is in need of lump sum quantities of materials which has increased both their demand and price. The use of large quantities of cement leads to increasing CO2 emission and as a consequence, the greenhouse effect. Consumption of wastes and byproducts from various sources in the manufacture of concrete has gained a great deal of importance in present days. Various researches are currently being conducted concerning the use of such products in concrete. RHA is a carbon neutral green product. Lots of ways are being thought of for disposing them by making commercial use of this. Rice husk ash is a good super-pozzolan which can be used to make special concrete mixes. The rice husk ash has been taken for this present study due to its easy availability and effective pozzolonic properties that are expected to improve the mechanical strength properties of concrete. Concrete specimens were made for evaluation of Compressive, Split Tensile, Flexural strength and Stress-Strain Behavior of concrete. The tests were conducted at the age of 7 and 28 days. Generally all mixes containing RHA achieved better properties than the conventional mix without RHA. By the experimental investigation the recommendation is given for using optimum percentage of RHA in concrete.

  19. 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.

  20. Adsorption of lead and copper ions from aqueous effluents on rice husk ash in a dynamic system

    Directory of Open Access Journals (Sweden)

    M. G. A. Vieira

    2014-06-01

    Full Text Available This study evaluated the kinetic adsorption of Pb and Cu ions using rice husk ash as adsorbent in a fixed bed. The maximum adsorption capacities obtained for lead and copper ions in the fixed bed were 0.0561 and 0.0682 mmol/g (at 20 ºC, respectively. The thermodynamic studies indicated that the lead adsorption process was exothermic and spontaneous, while the copper adsorption process was endothermic and spontaneous. Characterization results indicated the presence of several functional groups, amorphous silica and a fibrous and longitudinal structure of rice husks. Rice husk ash (RHA from northern Brazil can be used as a bioadsorbent for the individual removal of Pb(II and Cu(II ions from metal-containing effluents.

  1. Characterization of hydrochars produced by hydrothermal carbonization of rice husk

    Directory of Open Access Journals (Sweden)

    D. Kalderis

    2014-03-01

    Full Text Available Biochar is the carbon-rich product obtained when biomass, such as wood, manure or leaves, is heated in a closed container with little or no available air. In more technical terms, biochar is produced by so-called thermal decomposition of organic material under limited supply of oxygen (O2, and at relatively low temperatures (<700 °C. Hydrochar differentiates from biochar because it is produced in an aqueous environment, at lower temperatures and longer retention times. This work describes the production of hydrochar from rice husks using a simple, safe and environmentally-friendly experimental set-up, previously used for degradation of various wastewaters. Hydrochars were obtained at 200°C and 300°C and at residence times ranging from 2 to 16 h. All samples were then characterized in terms of yield, surface area, pH, conductivity and elemental analysis and two of them were selected for further testing with respect to heating values and heavy metal content.

  2. Preparation of an efficient humidity indicating silica gel from rice husk ash

    Indian Academy of Sciences (India)

    J P Nayak; J Bera

    2011-12-01

    An efficient humidity indicating silica gel was prepared using rice husk ash as a raw material via sodium silicate extraction and acid neutralization method. Cobalt chloride was impregnated into the silica gel as a colour indicating material. A low concentration of cobalt chloride solution (0.0005 mol dm-3) was used for the impregnation. The effect of pH of the impregnating solution on the colour development behaviour of the gel was investigated. The specific surface area of the gel was determined by Brunauer–Emmett–Teller method. The gel has been characterized using X-ray diffraction, scanning electron microscopy and visible spectroscopy. The moisture adsorption and desorption kinetics of the desiccant were evaluated using simultaneous thermogravimetry and differential scanning calorimetry.

  3. 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.

  4. Effect of silica forms in rice husk ash on the properties of concrete

    Science.gov (United States)

    Bui, Le Anh-Tuan; Chen, Chun-Tsun; Hwang, Chao-Lung; Wu, Wei-Sheng

    2012-03-01

    The strength and durability properties of concrete with or without three types of rice husk ash (RHA), namely, amorphous, partial crystalline, and crystalline RHA, were investigates. The three types of RHA were added into concrete at a 20% replacement level. Consequently, the pozzolanic reactivity of amorphous RHA was higher than that of partial crystalline and crystalline RHA. Concrete added with amorphous RHA showed excellent characteristics in its mechanical and durability properties. The results showed that the higher the amount of crystalline silica in RHA, the lower the concrete resistivity value became. When compared with each other, concretes with 20% of the cement replaced with these types of RHA achieved similar ultrasonic pulse velocity values, but all were lower than that of the control concrete. The incorporation of these kinds of RHA significantly reduced chloride penetration. The results not only encourage the use of amorphous materials, they also support the application of crystalline or partial crystalline RHA as mineral and pozzolanic admixtures for cement.

  5. Impact strength and abrasion resistance of high strength concrete with rice husk ash and rubber tires

    Directory of Open Access Journals (Sweden)

    M. B. Barbosa

    Full Text Available The paper discusses the application of High Strength Concrete (HSC technology for concrete production with the incorporation of Rice Husk Ash (RHA residues by replacing a bulk of the material caking and rubber tires with partial aggregate volume, assessing their influence on the mechanical properties and durability. For concrete with RHA and rubber, it was possible to reduce the brittleness by increasing the energy absorbing capacity. With respect to abrasion, the RHA and rubber concretes showed lower mass loss than the concrete without residues, indicating that this material is attractive to be used in paving. It is thus hoped that these residues may represent a technological and ecological alternative for the production of concrete in construction works.

  6. STRENGTH, CHLORIDE PERMEABILITY AND CORROSION OF COARSE FLY ASH CONCRETE WITH BAGASSE-RICE HUSK-WOOD ASH ADDITIVE

    Directory of Open Access Journals (Sweden)

    Veera Horsakulthai

    2013-01-01

    Full Text Available This study studied the utilization of Bagasse-Rice Husk-Wood Ash (BRWA as an additive for improving the strength and durability of coarse Fly Ash (FA concrete. The ground BRWA was used as an additive for maintaining the consistent slump of FA concrete. The strength, chloride permeability and corrosion resistance were investigated. The chloride permeability of concrete was evaluated using the measurement of coulomb charge as per ASTM C1202 and the corrosion resistance was detected using the Accelerated Corrosion test by Impressed Voltage (ACTIV. The test indicated that the incorporation of ground BRWA as an additive in FA concrete improved potentially both the strength and corrosion resistance, particularly the concrete containing up to 40% FA. While the 60% FA concrete with ground BRWA additive improved significantly in strength, the resistance to corrosion was insignificantly improved. The results showed that the use of ground BRWA as an additive was one approach for its utilization in concrete beyond use as pozzolan. The increase in the use of BRWA in concrete could reduce costs and minimize the environmental problems as well.

  7. 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.

  8. Prediction of Compressive Strength of Self compacting Concrete with Flyash and Rice Husk Ash using Adaptive Neuro-fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    S. S, Pathak

    2012-10-01

    Full Text Available Self-compacting concrete is an innovative concrete that does not require vibration for placing and compaction. It is able to flow under its own weight, completely filling formwork and achieving full compaction even in congested reinforcement without segregation and bleeding. In the present study self compacting concrete mixes were developed using blend of fly ash and rice husk ash. Fresh properties of theses mixes were tested by using standards recommended by EFNARC (European Federation for Specialist Construction Chemicals and Concrete system. Compressive strength at 28 days was obtained for these mixes. This paper presents development of Adaptive Neuro-fuzzy Inference System (ANFIS model for predicting compressive strength of self compacting concrete using fly ash and rice husk ash. The input parameters used for model are cement, fly ash, rice husk ash and water content. Output parameter is compressive strength at 28 days. The results show that the implemented model is good at predicting compressive strength.

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

    Science.gov (United States)

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

    2017-04-25

    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 arsenic and fluoride 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. The characterization of adsorbents were done 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(-) were 2.17 μg g(-1) and 2.91 mg g(-1) respectively. The optimum As and F(-) removal was observed between pH 7 and 9. The sorption process was well explained with pseudo-second order kinetic model. The As 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.

  10. An investigation of Crater Diameter on Plain Slab Foamed Concrete Rice Husk Ash (FCRHA Exposed to Low Impact Loading

    Directory of Open Access Journals (Sweden)

    Hadipramana Josef

    2017-01-01

    Full Text Available As sustainable material building and construction, the foamed concrete (FC in this investigation was modified by adding the Rice Husk Ash (RHA as sand replacement to increase its strength. Furthermore, this modification material (is called FCRHA treated on impact loading. This investigation was motivated when the plain slab of FCRHA subjected to small impactor, then the nose impactor over all would penetrate into slab target due to porosity of FCRHA. The experimental produced plain slabs FCRHA and FC (as a control with 1400 kg/m3 and 1600 Kg/m3 of densities. In impact test all plain slabs exposed by 40 mm steel blunt nose impactor with various impact velocities. The result showed the crater which produced by impact loading was not found spalling, scabbing, radial crack and widely cratering. This local damage occurred when porosity of FCRHA took over the impact loading. The nose impactor over all considered have been successful penetrated into slab of FCRHA and FC. Therefore, the diameter of crater equals to diameter of impactor. With this certainty, the prediction penetration depth on plain slab FCRHA (also FC can be determined in future investigation. In addition, the penetration of impactor on FCRHA with low impact velocity give the same impression on penetration impactor with high impact velocity on FC.

  11. 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.

  12. 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.

  13. 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.

  14. BATCH STUDY, EQUILIBIRUM AND KINETICS OF ADSORPTION OF SELENIUM USING RICE HUSK ASH (RHA

    Directory of Open Access Journals (Sweden)

    KAILAS L. WASEWAR

    2011-10-01

    Full Text Available The present work involves the study of Se(IV adsorption onto rice husk ash (RHA. The adsorbents were coated with the ferric chloride solution for the effective removal of selenium. The physico-chemical characterization of the adsorbents was carried out using standard methods, e.g., proximate analysis, scanning electron microscopy (SEM, fourier transform infrared spectroscopy (FTIR, thermo-gravimetric (TGA and differential thermal analysis (DTA, etc. Batch experiments were carried out to determine the effect of various factors such as adsorbent dose (w, initial pH, contact time (t, and temperature (T on adsorption process. Se(IV adsorption is high at low pH values, and decreased with the rise in initial pH. Temperature study shows that the uptake of Se(IV is more at 293 K within the temperature range studied. The parameters of Pseudo-First order, Pseudo-Second order kinetics, Weber-Morris intra particle kinetics have been determined. Equilibrium isotherms have been analyzed using Langmuir isotherm, Freundlich isotherm and Temkin isotherm. Error analysis has also been done using hybrid fractional error function (HYBRID and Marquardt’s percent standard deviation (MPSD.

  15. 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.

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

    Science.gov (United States)

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

    2016-11-01

    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.

  17. 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.

  18. The Phase-Formation Behavior of Composite Ceramic Powders Synthesized by Utilizing Rice Husk Ash from the Biomass Cogeneration Plant

    Directory of Open Access Journals (Sweden)

    Wenjie Yuan

    2015-01-01

    Full Text Available The development and utilization of biomass as a vital source of renewable energy were stimulated in order to reduce the global dependency on fossil fuels. A lot of rice husk ashes (RHA were generated as the waste after the rice husk as the main fuel was burnt in the biomass cogeneration plant. The phase-formation behavior of composite ceramic powders synthesized by using rice husk ash from the biomass cogeneration plant at the different carbon ratios and temperatures was investigated. The sequence of phase formation with the calcining temperatures ranging from 1773 K to 1853 K was followed by O′-Sialon→SiC + Si3N4→SiC in samples with C/SiO2  =  1 : 1–4 : 1. Ca-α-Sialon formed in samples with C/SiO2  =  5 : 1 and 6 : 1. The results highlighted that series of reactions happening sensitively depended on C/SiO2 and the temperature and demonstrated that the carbothermal nitridation provided an alternative for converting RHA waste into composite ceramic powders.

  19. 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.

  20. Evaluation of sulfate resistance of cement mortars containing black rice husk ash.

    Science.gov (United States)

    Chatveera, B; Lertwattanaruk, P

    2009-03-01

    In this paper, black rice husk ashes (BRHAs), which are agrowastes from an electricity generating power plant and a rice mill, were ground and used as a partial cement replacement. The durability of mortars under sulfate attack including expansion and compressive strength loss were investigated. For parametric study, BRHA were used as a Portland cement Type 1 replacement at the levels of 0%, 10%, 30%, and 50% by weight of binder. The water-to-binder ratios were 0.55 and 0.65. For the durability of mortar exposed to sulfate attack, 5% sodium sulfate (Na2SO4) and magnesium sulfate (MgSO4) solutions were used. As a result, when increasing the percentage replacement of BRHA, the expansion and compressive strength loss of mortar decreased. At the replacement levels of 30% and 50% of BRHA, the expansion of the mortars was less than those mixed with sulfate-resistant cement. However, the expansion of the mortars exposed to Na2SO4 was more than those exposed to MgSO4. Increasing the replacement level of BRHA tends to reduce the compressive strength loss of mortars exposed to Na2SO4 attack. In contrary, under MgSO4 attack, when increasing the replacement level of BRHA, the compressive strength loss increases from 0% to 50% in comparison to Portland cement mortar. Results show that ground BRHA can be applied as a pozzolanic material to concrete and also improve resistance to sodium sulfate attack, but it can impair resistance to magnesium sulfate attack.

  1. Synthesis of NaX zeolite using silica from rice husk ash

    Energy Technology Data Exchange (ETDEWEB)

    Dalal, A.K.; Gokhale, K.V.G.K.; Rao, M.S.

    1985-09-01

    Sodium X zeolite has been synthesized by using rice husk ash as a source of silica for the first time. The synthesis has been carried out for temperatures ranging from 95 to 120 /sup 0/ C and duration of synthesis from 1 to 24 h with SiO/sub 2//AI/sub 2/O/sub 3/, Na/sub 2/O/AI/sub 2/O/sub 3/, and H/sub 2/O/AI/sub 2/O/sub 3/ molar ratios ranging from 2.0 to 7.0, 2.4 to 10.0, and 96.0 to 890.0, respectively. The roles of temperature, duration of synthesis, and composition of initial mix in the formation of NaX zeolite and the stability of NaX zeolite were studied. In the present study, it has been observed that the NaX zeolite can be synthesized from an initial mix with SiO/sub 2//AI/sub 2/O/sub 3/ and Na/sub 2/O/SiO/sub 2/ molar ratios varying from 3 to 5.5 and 0.75 to 2.22, respectively, and having H/sub 2/O/Na/sub 2/O molar ratios from 30 to 60 at 100 /sup 0/ C with reaction times of 6 to 8 h. The product at each stage has been characterized by X-ray diffraction analysis. Studies on the crystallization kinetics and morphological investigations for the formation of NaX zeolite were also carried out.

  2. Adsorption and detection of some phenolic compounds by rice husk ash of Kenyan origin.

    Science.gov (United States)

    Mbui, Damaris N; Shiundu, Paul M; Ndonye, Rachel M; Kamau, Geoffrey N

    2002-12-01

    Rice husk ash (RHA) obtained from a rice mill in Kenya has been used as an inexpensive and effective adsorbent (and reagent) for the removal (and detection) of some phenolic compounds in water. The abundantly available rice mill waste was used in dual laboratory-scale batch experiments to evaluate its potential in: (i) the removal of phenol, 1,3-dihydroxybenzene (resorcinol) and 2-chlorophenol from water; and (ii) the detection of 1,2-dihydroxybenzene (pyrocatechol) and 1,2,3-trihydroxybenzene (pyrogallol) present in an aqueous medium. The studies were conducted using synthetic water with different initial concentrations of the phenolic compounds. The effects of different operating conditions (such as contact time, concentration of the phenolic compounds, adsorbent quantity, temperature, and pH) were assessed by evaluating the phenolic compound removal efficiency as well as the extent of their color formation reactions (where applicable). RHA exhibits reasonable adsorption capacity for the phenolic compounds and follows both Langmuir and Freundlich isotherm models. Adsorption capacities of 1.53 x 10(-4), 8.07 x 10(-5), and 1.63 x 10(-6) mol g(-1) were determined for phenol, resorcinol and 2-chlorophenol, respectively. Nearly 100% adsorption of the phenolic compounds was possible and this depended on the weight of RHA employed. For the detection experiments, pyrocatechol and pyrogallol present in water formed coloured complexes with RHA, with the rate of colour formation increasing with temperature, weight of RHA, concentration of the phenolic compounds and sonication. This study has proven that RHA is a useful agricultural waste product for the removal and detection of some phenolic compounds.

  3. 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.; D. S. Karam; Aris, A. Z.

    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...

  4. 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.; Aris, A. Z.

    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...

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

    African Journals Online (AJOL)

    acer

    ABSTRACT: Compressive strength tests were carried out on six mortar cubes with cement replaced by rice husk ... This result, therefore, indicated that RHA can be used as cement substitute ..... The loss on ignition obtained (18.25%) is higher.

  6. Effect of Specimen Size on the Tensile Strength Behavior of the Plastic Waste Fiber Reinforced Soil – Lime – Rice Husk Ash Mixtures

    Directory of Open Access Journals (Sweden)

    Muntohar A.S.

    2011-01-01

    Full Text Available Improvement of tensile strength in fiber reinforced soil is an important research topic. A study has been undertaken to investigate the strength of stabilized clay-soil reinforced with randomly distributed discrete plastic waste fibers by carrying out split tensile strength test. In this study, the clay soil was stabilized with lime and rice husk ash mixtures. The main purpose of this research is to investigate the effect of specimen size to the tensile strength behavior. Testing procedure was formulated using extended ASTM C496 standard. The laboratory investigation results showed that split-tensile strength of reinforced specimens increased with increase in size. The limitations of the dataset indicate that specimen size of 70 mm in diameter is the threshold to produce reasonable representative strengths.

  7. 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.

  8. Efeito da adição de cinza da casca de arroz em misturas cimento-casca de arroz Effect of the addition of rice husk ash in cement-rice husk mixtures

    Directory of Open Access Journals (Sweden)

    Loris L. Zucco

    2008-06-01

    Full Text Available A casca de arroz e sua cinza são abundantes e renováveis, podendo ser empregadas na obtenção de materiais de construção alternativos. O aumento do consumo desses resíduos poderia ajudar a minimizar os problemas ambientais provenientes da sua eliminação inadequada. Este trabalho teve o objetivo de avaliar a utilização de cinzas como carga mineral (filler. Todavia, a casca de arroz interferiu quimicamente no comportamento das misturas à base de cimento. Assim, diferentes misturas cimento-casca de arroz, com e sem adição de cinzas, foram avaliadas, a fim de destacar a influência de seus componentes (casca; cinza que, de outra forma, poderiam ser excluídas ou subestimadas. Amostras cilíndricas (teste de compressão simples e de tração por compressão diametral e amostras extraídas das placas prensadas (teste de flexão e compressão paralela à superfície foram usadas para avaliar o comportamento das misturas e dos componentes casca e cinza. Os resultados dos ensaios mecânicos mostraram, em geral, que não houve diferença estatística entre as misturas, as quais estão associadas ao efeito químico supressivo da cinza da casca de arroz. A mistura da casca de arroz de 10 mm com o acréscimo de 35% das cinzas destaca-se por permitir o mais elevado consumo de casca e cinzas, reduzir 25% no consumo de cimento e permitir o confinamento (sem emissões para a atmosfera de cerca de 1,9 tonelada de CO2 por tonelada de cimento consumido, contribuindo, assim, para a redução da emissão de CO2, o que pode incentivar construções rurais sob o ponto de vista ecológico.The rice husk and its ash are abundant and renewable and can be used to obtain alternative building materials. An increase in the consumption of such waste could help minimize the environmental problems from their improper disposal. This study aimed to evaluate the use of ashes as a cargo mineral (filler. However, the rice husk chemically interferes in the conduct of the

  9. COMPARATIVE ANALYSIS OF OXALIC ACID PRODUCED FROM RICE HUSK AND PADDY

    Directory of Open Access Journals (Sweden)

    P.I. Oghome

    2012-09-01

    Full Text Available In this research work, comparative analysis of Oxalic acid produced from Rice husk and Paddy was carried out in order to ascertain which waste sample produced a better yield. Nitric acid oxidation of carbohydrates was the method adopted in the production. The variable ratios of HNO3:H2SO4 used were 80:20, 70:30, 60:40, and 50:50. The variable ratio of 60:40 gave the maximum yield and at a maximum temperature of 75oC. Rice husk sample gave a percentage yield of 53.2, 64.4, 81.0, and 53.3 at temperatures of 55 oC, 65 oC, 75 oC, and 85 oC respectively. In the case of paddy a percentage yield of 53.1, 64.0, 79.9, and 52.8 at temperatures of 55 oC, 65 oC, 75 oC, and 85 oC were obtained respectively. The plots between yield and temperature at different variable ratios illustrate the dependence of yield on temperature, which was similar to a parabolic relationship and the peak value (yield was at 75 oC above which it decreased. The properties of oxalic acid from both sources were very close and compared favourably with literature. In comparing the yield, oxalic acid produced from Rice husk gave higher yield than that from Paddy.

  10. Study of silica templates in the rice husk and the carbon-silica nanocomposites produced from rice husk

    Science.gov (United States)

    Larichev, Yu. V.; Yeletsky, P. M.; Yakovlev, V. A.

    2015-12-01

    Carbon-silica nanocomposites obtained by rice husk carbonization in a fluidized-bed reactor using a deep oxidation copper-chromium catalyst were studied. Dispersion characteristics of the silica phase in these systems were determined by small-angle X-ray scattering (SAXS) using the full contrast technique. SiO2 was found in the initial rice husk as compact nanoparticles having a wide size distribution. This distribution consists of a narrow fraction with particle sizes from 1 to 7 nm and a wider fraction with particle sizes from 8 to 22 nm. Oxidative heat treatment of rice husk in a fluidized bed in the presence of the catalyst decreased the fraction of small SiO2 particles and increased the fraction of large ones. It was demonstrated that the particle size of silica in the carbon matrix can be determined selectively for deliberate design of porous carbon materials with desired properties.

  11. Characterization of hydrochars produced by hydrothermal carbonization of rice husk

    Science.gov (United States)

    Kalderis, D.; Kotti, M. S.; Méndez, A.; Gascó, G.

    2014-06-01

    Biochar is the carbon-rich product obtained when biomass, such as wood, manure or leaves, is heated in a closed container with little or no available air. In more technical terms, biochar is produced by so-called thermal decomposition of organic material under limited supply of oxygen (O2), and at relatively low temperatures (heating values and heavy metal content. The surface area was low for all hydrochars, indicating that porous structure was not developed during treatment. The hydrochar obtained at 300 °C and 6 h residence times showed a predicted higher heating value of 17.8 MJ kg-1, a fixed carbon content of 46.5% and a fixed carbon recovery of 113%, indicating a promising behaviour as a fuel.

  12. 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

  13. 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%.

  14. 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.

  15. 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%.

  16. 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.

  17. Application of cationic hemicelluloses produced from corn husk as polyelectrolytes in sewage treatment

    Directory of Open Access Journals (Sweden)

    Alan Soares Landim

    2013-01-01

    Full Text Available Hemicelluloses were extracted from corn husk and converted into cationic hemicelluloses using 2,3-epoxypropyltrimethylammonium chloride. The degree of substitution was determined as 0.43 from results of elemental analysis. The cationic derivative was also characterized by Fourier transform infrared spectroscopy and Carbon-13 magnetic nuclear ressonance. The produced polymer was employed as coagulant aid in a sewage treatment station (STS of the municipal department of water and sewer (Departamento Municipal de Água e Esgoto - DMAE in Uberlândia-Minas Gerais, Brazil, using Jar test experiments. Its performance was compared to ACRIPOL C10, a commercial cationic polyacrylamide regularly used as a coagulant at the STS. The best result of the jar-test essays was obtained when using cationic hemicelluloses (10 mg L- 1 as coagulant aid and ferric chloride as coagulante (200 mg L- 1. The resultsof color and turbidity reduction, 37 and 39%, respectively, were better than when using only ferric chloride. These results were also higher than those of commercial polyacrylamide, on the order of 32.4 and 38.7%, respectively. The results showed that the cationic hemicelluloses presented similar or even superior performance when compared to ACRIPOL C10, demonstrating that the polyelectrolytes produced from recycled corn husks can replace commercial polymers in sewage treatment stations.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Paddy Husk as Support for Solid State Fermentation to Produce Xylanase from Bacillus pumilus

    Institute of Scientific and Technical Information of China (English)

    Ranganathan KAPILAN; Vasanthy ARASARATNAM

    2011-01-01

    To optimize culture conditions for xylanase production by solid state fermentation (SSF) using Bacillus pumilus,with paddy husk as support,solid medium contained 200 g of paddy husk with 800 mL of liquid fermentation medium [xylan,20.0 g/L; peptone,2.0 g/L; yeast extract,2.5 g/L; K2HPO4,2.5 g/L; KH2PO4,1.0 g/L; NaCl,0.1 g/L; (NH4)2SO4,2.0 g/L,CaCl22H2O,0.005 g/L; MgCl2·6H2O,0.005 g/L; and FeCl3,0.005 g/L] at pH 9.0 was applied.The highest xylanase activity (142.0 +0.47 U/g DM] was obtained on the 6th day at 30℃.The optimized paddy husk to liquid fermentation medium ratio was 2∶9,and the optimized culture temperature was 40℃.When commercial Birchwood xylan was replaced with different concentrations of corncob,xylanase production was maximized (224.2 U/g DM) in the medium with 150 g/L corncob.Xylanase production was increased by sucrose,fructose and arabinose,whereas reduced by glucose,galactose,lactose and amylose.When organic nitrogen sources were replaced with locally available nitrogen sources such as groundnut powder or sesame seedcake powder or coconut seedcake powder or soy meal powder,the highest xylanase production (290.7 U/g DM) was obtained in the medium with soy meal powder and 16.0 g/L of soy meal powder was the optimum (326.5±0.34 U/g DM).Based on the optimization studies,B.pumilus produced 2.3 times higher xylanase activity.The medium cost was reduced from 2 458.3 to 178.3 SLR/kg and the total activity which could be obtained from 1 kg of the medium was increased from 48 624 to 220 253 Units.

  3. 由稻壳灰合成P型分子筛%Synthesis of zeolite P from rice husk ash

    Institute of Scientific and Technical Information of China (English)

    付颖寰; 张绥英; 马红超; 陈丽凤; 马春; 宋宇; 董晓丽

    2011-01-01

    Synthesis of zeolite P by hydrothermal method using rice husk ash as silicon source was optimized. It was found that the maximum calcium exchange ability of zeolite P is 305.4 mg/g when synthesis was carried out at 1.2 of n(Na2O)/n(SiO2) molar ratio, 7.0 of n(SiO2)/n(Al2O3) molar ratio, 25 of n(H2O)/n(Na2O) and 85℃ of crystallizing temperature for 10 h. analysis by X ray diffraction and SEM suggested the better characteristic peak and the narrower grain-size distribution.%以农业废弃物稻壳经酸化处理、焙烧所得的稻壳灰为硅源,通过水热法未经老化过程及添加晶种直接合成了P型分子筛.采用钙交换能力、XRD和SEM对所合成产物的晶体结构、表面形貌和离子交换性能进行了表征.研究结果表明,该工艺合成P型分子筛的最佳条件为:n(Na2O)/n(SiO2)=1.2,n(SiO2)/n(Al2O3)=7.0,n(H2O)/n(Na2O)=25,于85℃反应10 h,在此条件下合成的P型分子筛产品具有较高的结晶度,无杂相且晶粒精细,其钙交换能力达到每克P型分子筛可吸收305.4 ng碳酸钙.

  4. 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.

  5. Combustion of coffee husks

    Energy Technology Data Exchange (ETDEWEB)

    Saenger, M.; Hartge, E.-U.; Werther, J. [Technical Univ. Hamburg-Harburg, Chemical Engineering 1, Hamburg (Germany); Ogada, T.; Siagi, Z. [Moi Univ., Dept. of Production Engineering, Eldoret (Kenya)

    2001-05-01

    Combustion mechanisms of two types of coffee husks have been studied using single particle combustion techniques as well as combustion in a pilot-scale fluidized bed facility (FBC), 150 mm in diameter and 9 m high. Through measurements of weight-loss and particle temperatures, the processes of drying, devolatilization and combustion of coffee husks were studied. Axial temperature profiles in the FBC were also measured during stationary combustion conditions to analyse the location of volatile release and combustion as a function of fuel feeding mode. Finally the problems of ash sintering were analysed. The results showed that devolatilization of coffee husks (65-72% volatile matter, raw mass) starts at a low temperature range of 170-200degC and takes place rapidly. During fuel feeding using a non water-cooled system, pyrolysis of the husks took place in the feeder tube leading to blockage and non-uniform fuel flow. Measurements of axial temperature profiles showed that during under-bed feeding, the bed and freeboard temperatures were more or less the same, whereas for over-bed feeding, freeboard temperatures were much higher, indicating significant combustion of the volatiles in the freeboard. A major problem observed during the combustion of coffee husks was ash sintering and bed agglomeration. This is due to the low melting temperature of the ash, which is attributed to the high contents of K{sub 2}O (36-38%) of the coffee husks. (Author)

  6. Corrosion and wear behaviour of Al–Mg–Si alloy matrix hybrid composites reinforced with rice husk ash and silicon carbide

    OpenAIRE

    Kenneth Kanayo Alaneme; Tolulope Moyosore Adewale; Peter Apata Olubambi

    2014-01-01

    The corrosion and wear behaviour of Al–Mg–Si alloy matrix hybrid composites developed with the use of rice husk ash (RHA) and silicon carbide (SiC) particulates as reinforcements were investigated. RHA and SiC mixed in weight ratios 0:1, 1:3, 1:1, 3:1, and 1:0 were utilized to prepare 5, 7.5 and 10 wt% of the reinforcing phase with Al Mg Si alloy as matrix using double stir casting process. Open circuit corrosion potential (OCP) and potentiodynamic polarization measurements were used to study...

  7. 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.

  8. Rice husk ash supported FeCl2·2H2O:A mild and highly efficient heterogeneous catalyst for the synthesis of polysubstituted quinolines by Friedländer heteroannulation

    Institute of Scientific and Technical Information of China (English)

    Farhad Shirini; Somayeh Akbari-Dadamahaleh; Ali Mohammad-Khah

    2013-01-01

    Rice husk ash was used as a new, green, and cheap adsorbent for FeCl3. Characterization of the ob-tained reagent showed that rice husk ash supported FeCl2·2H2O was formed. This reagent is effi-cient at catalyzing the synthesis of multisubstituted quinolines by the Friedländer heteroannulation of o-aminoaryl ketones with ketones orβ-diketones under mild reaction conditions. This method-ology allows for the synthesis of a broad range of substituted quinolines in high yields and with excellent regioselectivity in the absence of a solvent.

  9. 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

  10. 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.

  11. CHARACTERIZATION AND COMPARISON OF TREATED AND UNTREATED RICH HUSH ASH & FLY ASH FOR METAL MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    Ravinder Pal Singh

    2011-10-01

    Full Text Available Rice Husk ash and fly ash are agricultural and coal wastes respectively. These are produced in abundance globally and poses risk to health as well as environment. Thus their effective, conducive and eco-friendly utilization has always been a challenge for scientific community. The fly ash has been used as reinforcement for improved mechanical properties of composites (1,3-5,9. Rice husk ash can also be used for similar applications as its composition is almost similar to that of fly ash. This paper mainly deals with identification ofcharacteristics of both the fly ash and rice husk ash using spectroscopic and microscopic analysis. SEM, XRD,XRF and FTIR spectroscopic methods were used for the characterization of treated and untreated ashes. The results were compared and it was observed that both ashes possesses nearly same chemical phases and otherfunctional groups thus proposing the use of rice husk ash as reinforcement like fly ash in Metal Matrix Composites (MMCs specifically for wear resistance applications.

  12. efficacy of rice husk ash against rice weevil and lesser grain borer ...

    African Journals Online (AJOL)

    ACSS

    Similar numbers of R. dominica progeny were produced in the control, RHAL, and RHAH treatments (78.4, 92.9 and 64.3 .... incubator for an additional 54 days (68 days post-treatment) before ..... Habeeb, G.A. and Mahmud, H.B. 2010. Study.

  13. Characteristics and mechanisms of nickel adsorption on biochars produced from wheat straw pellets and rice husk.

    Science.gov (United States)

    Shen, Zhengtao; Zhang, Yunhui; McMillan, Oliver; Jin, Fei; Al-Tabbaa, Abir

    2017-05-01

    The adsorption characteristics and mechanisms of Ni(2+) on four-standard biochars produced from wheat straw pellets (WSP550, WSP700) and rice husk (RH550, RH700) at 550 and 700 °C, respectively, were investigated. The kinetic results show that the adsorption of Ni(2+) on the biochars reached an equilibrium within 5 min. The increase of the solid to liquid ratio resulted in an increase of Ni(2+) removal percentage but a decrease of the adsorbed amount of Ni(2+) per weight unit of biochar. The Ni(2+) removal percentage increased with the increasing of initial solution pH values at the range of 2-4, was relatively constant at the pH range of 4-8, and significantly increased to ≥98% at pH 9 and stayed constantly at the pH range of 9-10. The calculated maximum adsorption capacities of Ni(2+) for the biochars follow the order of WSP700 > WSP550 > RH700 > RH550. Both cation exchange capacity and pH of biochar can be a good indicator of the maximum adsorption capacity for Ni(2+) showing a positively linear and exponential relationship, respectively. This study also suggests that a carefully controlled standardised production procedure can make it reliable to compare the adsorption capacities between different biochars and investigate the mechanisms involved.

  14. Producing a synthetic zeolite from secondary coal fly ash.

    Science.gov (United States)

    Zhou, Chunyu; Yan, Chunjie; Zhou, Qi; Wang, Hongquan; Luo, Wenjun

    2016-11-01

    Secondary coal fly ash is known as a by-product produced by the extracting alumina industry from high-alumina fly ash, which is always considered to be solid waste. Zeolitization of secondary coal fly ash offers an opportunity to create value-added products from this industrial solid waste. The influence of synthesis parameters on zeolite NaA such as alkalinity, the molar ratio of SiO2/Al2O3, crystallization time and temperature was investigated in this paper. It was found that the types of synthetic zeolites produced were to be highly dependent on the conditions of the crystallization process. Calcium ion exchange capacity and whiteness measurements revealed that the synthesized product meets the standard for being used as detergent, indicating a promising use as a builder in detergent, ion-exchangers or selective adsorbents. Yield of up to a maximum of 1.54 g/g of ash was produced for zeolite NaA from the secondary coal fly ash residue. This result presents a potential use of the secondary coal fly ash to obtain a high value-added product by a cheap and alternative zeolitization procedure.

  15. 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

  16. STUDY OF EXPANSIVE REACTIONS IN MORTAR MADE OF PORTLAND CEMENT WITH RICE HUSK ASH (RHA = ESTUDO DE REAÇÕES EXPANSIVAS EM ARGAMASSAS DE CIMENTO PORTLAND COM CINZA DE CASCA DE ARROZ (CCA

    Directory of Open Access Journals (Sweden)

    Jorge Luis Akasaki

    2007-01-01

    Full Text Available Rice husk is an agroindustrial residue which, when adequately burned and ground, may become an important pozzolan to be added in mortars. One factor contributing to the feasibility of its use is that of the 10 million tons of rice produced annually in this country, two million tons of husk remain, which can produce about 400 thousand tons of ash - enough to supply the market for mortars, concrete andothers. This large amount of material has become an environmental problem because it is being discarded inappropriately. Seeking a viable use of rice husk ash in the civil construction, the present research studies the variation in mortar behavior with different levels of RHA (Rice Husk Ash. Prismatic specimens were used, measuring 25x25x285mm, moulded with 0% (reference, 5%, 10% and 25% RHA. The influence of the RHA’s was verified through the following tests: efficiency of pozzolanic materials in avoiding expansion and alkali-aggregate reaction. The result obtained in the expansion reduction test (NBR 12651 showed that RHA reduces considerably the expansion of mortars due to reaction with the alkalis in the cement(94.29%, with the minimum reduction required by the norm for a pozolan being 75%. Although the expansion values in the alkali-aggregate reaction test (ASTM C-1260 remained above the limit allowed to consider the material innocuous, RHA levels of 5% as well as 10% obtained better results (expanded less then the referenceline. = A casca de arroz é um resíduo agroindustrial que adequadamente queimada e moída, pode se tornar uma importante pozolana a ser adicionada em argamassas. Um fator que viabiliza o seu emprego, é que dos 10 milhões de toneladas de arroz que o país produz por ano, sobram dois milhões de toneladas de casca – que podem rendercerca de 400 mil toneladas de cinza, o suficiente para suprir o mercado de argamassas, concreto e outros. Esta grande quantidade de material produzido passa a se tornar um problema, porque

  17. Effectiveness of Rice Husk Ash in Removal of Phenolic Compounds from Aqueous Solutions, Equilibrium and Kinetics Studies

    Directory of Open Access Journals (Sweden)

    Majid Kermani

    2012-04-01

    Full Text Available Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives: Phenols in trace quantities are usually present in the treated effluent of many wastewater-treatment plants. Phenol compounds even at low concentration can cause toxicity, health and significant taste and odor problem in drinking waters. This research focuses on understanding the sorption process and developing a cost-effective technology for the treatment of water contaminated with phenolic compounds, which are discharged into the aquatic environment from a variety of sources. In order to remove phenolic compounds from water, a new natural sorbent, rice husk ash, was developed.Materials and Methods: Removal of phenol, 2-chlorophenol and 4-chlorophenol were characterized by spectrophotometric technique at wavelengths of 269.5, 274 and 280 nm, respectively, under batch equilibrium conditions and via changing the parameters of contact time, initial pH, and initial concentration of adsorbates and dosages of sorbent. Finally, the results were analyzed by the kinetic and isotherm models.Results: in this study, the equilibrium time was found to be 240 min for full equilibration of adsorbates. Removal percent of 2-chlorophenol was lower than two others. The maximum removal of phenol, 2-CP and 4-CP was observed at an initial pH of 5. The percentage removal of these phenolic compounds increased with increasing adsorbent dose and decreasing initial concentration. In kinetics studies, correlation coefficient and ARE factor showed that the sorption of phenol (R2=0.9999, 2-chlorophenol (R2=0.9992 and 4-chlorophenol (R2=1 fitted by pseudo second order model. Isotherm studies also revealed that, Langmuirmodel for phenol (R2=0.9499, Freundlich model for 2-chlorophenol (R2=0.9659 and 4-chlorophenol (R2=0.9542 were the best choices to describe the sorption behaviors.Conclusion: Sorption process is highly dependent on the pH and it affects adsorbent surface

  18. Rice husk ash as a renewable source for the production of zeolite NaY and its characterization

    Directory of Open Access Journals (Sweden)

    R.M. Mohamed

    2015-01-01

    Full Text Available Zeolite Y in sodium form (NaY was synthesized using silica source from rice husk. The as-synthesized samples were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM, X-ray fluorescence (XRF, BET. As results, we verify that NaY zeolite obtained from the two-step route, presents a good degree of crystallinity and then can be suitable for using in various applications.

  19. Generation of volcanic ash: a textural study of ash produced in various laboratory experiments

    Science.gov (United States)

    Lavallée, Yan; Kueppers, Ulrich; Dingwell, Donald B.

    2010-05-01

    In volcanology, ash is commonly understood as a fragment of a bubble wall that gets disrupted during explosive eruptions. Most volcanic ashes are indeed the product of explosive eruptions, but the true definition is however that of a particle size being inferior to 2 mm. The term does not hold any information about its genesis. During fragmentation, particles of all sizes in various amounts are generated. In nature, fragmentation is a brittle response of the material (whether a rock or magma) caused by changes in 1) strain rate and 2) temperature, and/or 3) chemical composition. Here we used different experimental techniques to produce ash and study their physical characteristics. The effects of strain rate were investigated by deforming volcanic rocks and magma (pure silicate melt and crystal-bearing magma) at different temperatures and stresses in a uniaxial compression apparatus. Failure of pure silicate melts is spontaneous and generates more ash particles than fragmentation of crystal-bearing melts. In the latter, the abundance of generated ash correlates positively with the strain rate. We complemented this investigation with a study of particles generated during rapid decompression of porous rocks, using a fragmentation apparatus. Products of decompression experiments at different initial applied pore pressure show that the amount of ash generated by bubble burst increase with the initial applied pressure and the open porosity. The effects of temperature were investigated by dropping pure silicate melts and crystal-bearing magma at 900 and 1100°C in water at room temperature. Quenching of the material is accompanied by rapid contraction and near instantaneous fragmentation. Pure silicate melts respond more violently to the interaction with water and completely fragmented into small particles, including a variety of ash morphologies and surface textures. Crystal-bearing magmas however fragmented only very partially when in contact with water and produced a

  20. Assessment of Concrete Strength Using Partial Replacement of Coarse Aggregate for Wast Tiles and Cement for Rice Husk Ash in Concrete

    Directory of Open Access Journals (Sweden)

    Umapathy U

    2014-05-01

    Full Text Available Conservation of natural resources and preservation of environment is the essence of any development. The problem arising from continuous technological and industrial development is the disposal of waste material. If some of the waste materials are found suitable in concrete making, not only cost of construction can be cut down, but also safe disposal of waste materials can be achieved. So in our project, an attempt has been made to assess the suitability of stone with waste tills in concrete making. In the laboratory tiles has been tried as coarse aggregate has been used as partial substitute to conventional coarse aggregate concrete making and today many researches are ongoing into the use of Portland cement replacements, using many waste materials like pulverized fly ash (PFA and ground granulated blast furnace slag (GGBS. Like PFA and GGBS a waste glass powder (GLP is also used as a binder with partial replacement of cement which takes some part of reaction at the time of hydration. In this study, rice husk ash have been used as partially replacements to the cement Cubes were cast and tested for compressive strength, and modulus of rupture after a curing period of 7,17,28 days.

  1. Reuse of sugarcane bagasse ash (SCBA) to produce ceramic materials.

    Science.gov (United States)

    Souza, A E; Teixeira, S R; Santos, G T A; Costa, F B; Longo, E

    2011-10-01

    Sugarcane bagasse ash (SCBA) is a residue resulting from the burning of bagasse in boilers in the sugarcane/alcohol industry. SCBA has a very high silica concentration and contains aluminum, iron, alkalis and alkaline earth oxides in smaller amounts. In this work, the properties of sintered ceramic bodies were evaluated based on the concentration of SCBA, which replaced non-plastic material. The ash was mixed (up to 60 wt%) with a clayed raw material that is used to produce roof tiles. Prismatic probes were pressed and sintered at different temperatures (up to 1200 °C). Technological tests of ceramic probes showed that the addition of ash has little influence on the ceramic properties up to 1000 °C. X-ray diffraction and thermal analysis data showed that, above this temperature the ash participates in the sintering process and in the formation of new important phases. The results reported show that the reuse of SCBA in the ceramic industry is feasible.

  2. On Technique of Preparing Silicon-Iron-Peach by Using Rice Husk Ash%稻壳灰制备硅铁红的工艺研究

    Institute of Scientific and Technical Information of China (English)

    章慧芳; 蔡景清; 蔡新安; 刘文茂; 裴剑锋

    2013-01-01

    [目的]研究了稻壳灰制备硅铁红的工艺,为拓宽稻壳灰综合利用途径提供参考.[方法]在微波辐射条件下,采用稻壳灰为原料制备水玻璃,而后以此水玻璃为原料,利用溶胶-凝胶法,在微波辅助干燥条件下制备硅铁红颜料.同时考查了硅/铁摩尔比、微波辐射功率及时间、煅烧温度等因素对硅铁红包裹率的影响.[结果]研究表明,硅/铁摩尔比为7∶1,微波辐射功率和时间分别为600W和8min,前驱体煅烧温度和时间分别为750℃和2h;此条件下制备的Fe2O3/SiO2,其包裹率达到93.1%.[结论]在微波辅助下通过简单的sol-gel工艺,可以将SiO2玻璃包裹于Fe2O3颗粒表面而制备出硅铁红包裹颜料并且所制备的硅铁红包裹率高达93%左右,比市售硅铁红的包裹率要高.该工艺操作简单,适合工业化生产.%[Objective] The method for the preparation of the silicon-iron-peach (Fe2O3/SiO2) ceramic pigment by using the rice husk ash was studied,and it is hoped for supplying a new route to broaden the comprehensive utilization of the rice husk ash.[Method] Firstly,the rice husk ash was used for the preparation of the sodium silicate,and then the obtained sodium silicate were used as the raw materials for the sol-gel synthesis of the Fe2O3/SiO2 powders.In this process,microwave was used for the drying of the Fe2O3/SiO2 powders.The effects of the mol ratio of Fe/Si,time and powder of microwave irradiation,and the sintering temperature on encapsulation rate of Fe2O3/SiO2 were studied.[Result] The optimal parameters for the synthesis of Fe2O3/SiO2 were listed as follows:the mol ratio of Fe/Si is 7∶ 1,then microwave radiated for 8 min with a power of 600 W,subsequently,sintered at 750 ℃ for 2 h to obtain Fe2O3/SiO2 ceramic pigment.The results indicated that the encapsulation rate of Fe2O3/SiO2 can reach 93.1%.[Conclusion] The method is easy to operate,and the encapsulation rate of the Fe2O3/SiO2 powders is more excellent

  3. Artificial neural networks for prediction of percentage of water absorption of geopolymers produced by waste ashes

    Indian Academy of Sciences (India)

    Ali Nazari

    2012-11-01

    In the present work, percentage of water absorption of geopolymers made from seeded fly ash and rice husk bark ash has been predicted by artificial neural networks. Different specimens, made from a mixture of fly ash and rice husk bark ash in fine and coarse form together with alkali activatormade of water glass and NaOH solution, were subjected to permeability tests at 7 and 28 days of curing. The curing regime was different: one set cured at room temperature until reaching to 7 and 28 days and the other sets were oven cured for 36 h at a range of 40–90 °C and then cured at room temperature for 7 and 28 days. To build the model, training and testing using experimental results from 120 specimens were conducted. According to these input parameters, in the neural networks model, the percentage of water absorption of each specimen was predicted. The training and testing results in the neural networks model have shown a strong potential for predicting the percentage of water absorption of the geopolymer specimens.

  4. Preparation of TiO2-SiO2 using Rice Husk Ash as Silica Source and The Kinetics Study as Photocatalyst in Methyl Violet Decolorization

    Directory of Open Access Journals (Sweden)

    Is Fatimah

    2015-03-01

    Full Text Available Preparation, characterization and utilization of TiO2-SiO2 as photocatalyst for methyl violet (MV decolorization has been conducted. In this research, preparation of TiO2-SiO2 was developed based on natural renewable silica source; rice husk ash (RHA via a sol-gel technique. The composite was formed by the dispersing of titanium isopropoxide as titania precursor into the gel of silica followed by aging, drying and calcination. The TiO2-SiO2 sample was characterized by powder X-ray diffraction (XRD, diffuse reflectance-UV Visible spectrophotometric analysis (DRUV-Vis, gas sorption analyzer and Scanning electron micrograph (SEM before its utilization as photocatalyst in methyl violet photooxidation. As comparison to the physicochemical character study, the synthesis of TiO2-SiO2 by using tetraethyl ortosilicate (TEOS was performed as a confirmation. Result showed that prepared TiO2-SiO2 has the character similar to TiO2-SiO2 as synthesized by TEOS precursor. The formation of crystalline titania in anatase and rutile phase was identified with increasing surface porosity data and the value of band gap energy which sufficiently contribute to a photocatalytic mechanism. The character data are in line with the kinetic data of methyl violet decolorization. From the compared photooxidation, photolysis, photocatalysis and adsorption process, it can be concluded that TiO2-SiO2 acts efficiently as a photocatalyst. © 2015 BCREC UNDIP. All rights reserved.Received: 23rd August 2014; Revised: 4th October 2014; Accepted: 20th October 2014 How to Cite: Fatimah, I., Said, A., Hasanah, U.A. (2015. Preparation of TiO2-SiO2 using Rice Husk Ash as Silica Source and The Kinetics Study as Photocatalyst in Methyl Violet Decolorization. Bulletin of Chemical Reaction Engineering & Catalysis, 10 (1: 43-49. (doi:10.9767/bcrec.10.1.7218.43-49Permalink/DOI: http://dx.doi.org/10.9767/bcrec.10.1.7218.43-49 

  5. 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.

  6. 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.

  7. Utilization of rice husk ash as silica source for the synthesis of mesoporous silicas and their application to CO2 adsorption through TREN/TEPA grafting.

    Science.gov (United States)

    Bhagiyalakshmi, Margandan; Yun, Lee Ji; Anuradha, Ramani; Jang, Hyun Tae

    2010-03-15

    Mesoporous MCM-41, MCM-48 and SBA-15 were synthesized using Rice husk ash (RHA) as the silica source and their defective Si-OH sites were functionalized by 3-chloropropyltrimethoxysilane (CPTMS) which was subsequently grafted with amine compounds, Tris(2-aminoethyl)amine (TREN) and Tetraethylenepentamine (TEPA). X-ray powder diffraction (XRD) and BET results of the parent mesoporous silica suggested their closeness of structural properties to those obtained from conventional silica sources. CO(2) adsorption of branched amine TREN and straight chain amine TEPA at 25, 50 and 75 degrees C was obtained by Thermogravimetric Analyser (TGA) at atmospheric pressure. TREN grafted mesoporous silica showed 7% of CO(2) adsorption while TEPA grafted mesoporous silicas showed less CO(2) adsorption, which is due to the presence of isolated amine groups in TREN. TREN grafted mesoporous silicas were also observed to be selective towards CO(2), thermally stable and recyclable. The order of CO(2) adsorption with respect to amount of amine grafting was observed to be MCM-48/TREN>MCM-41/TREN>SBA-15/TREN.

  8. Cocoa Husk/Cassava Leaf Inclusions in Layers Mash Produced Quality Cheap Feeds

    Directory of Open Access Journals (Sweden)

    Olubamiwa

    2001-01-01

    Full Text Available A 10-week trial was conducted to investigate the effects of cocoa husk meal (CHM/cassava leaf meal (CLM mixtures in layers mash on laying hen production performance and egg quality. Results were compared with those obtained using two locally popular standard commercial feeds (CFDs. CHM/CLM mixtures were included in the two test diets in the following order : Diet 1 (7.3 CHM/2.7 % CLM and Diet 2 (14.6 CHM/5.4 CLM. Forty 6-month-in-lay individually caged Black Nera hens were randomly allocated to the four diets. Feeding was ad libitum Feed intake, egg weight and percentage egg production were reduced (P <0.05 on Diet 2 relative to the CFDs. The reduction in egg weight was however marginal while the values were in line with the 56-58 g in the literature. Similarly, the value of 65 % percent egg production was considered not poor. Feed efficiency, yolk colour index, shell thickness and yolk percentage were not influenced by diet. On average, feed cost of the CHM/CLM diets were 60 % of those of the CFDs while the feed cost/kg egg was roughly doubled on the latter. It was concluded that the inclusion of CHM/CLM in layers mash promises to be a very economically rewarding venture where the two farm by-products are available.

  9. Porous materials produced from incineration ash using thermal plasma technology.

    Science.gov (United States)

    Yang, Sheng-Fu; Chiu, Wen-Tung; Wang, To-Mai; Chen, Ching-Ting; Tzeng, Chin-Ching

    2014-06-01

    This study presents a novel thermal plasma melting technique for neutralizing and recycling municipal solid waste incinerator (MSWI) ash residues. MSWI ash residues were converted into water-quenched vitrified slag using plasma vitrification, which is environmentally benign. Slag is adopted as a raw material in producing porous materials for architectural and decorative applications, eliminating the problem of its disposal. Porous materials are produced using water-quenched vitrified slag with Portland cement and foaming agent. The true density, bulk density, porosity and water absorption ratio of the foamed specimens are studied here by varying the size of the slag particles, the water-to-solid ratio, and the ratio of the weights of the core materials, including the water-quenched vitrified slag and cement. The thermal conductivity and flexural strength of porous panels are also determined. The experimental results show the bulk density and the porosity of the porous materials are 0.9-1.2 g cm(-3) and 50-60%, respectively, and the pore structure has a closed form. The thermal conductivity of the porous material is 0.1946 W m(-1) K(-1). Therefore, the slag composite materials are lightweight and thermal insulators having considerable potential for building applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Corrosion and wear behaviour of Al–Mg–Si alloy matrix hybrid composites reinforced with rice husk ash and silicon carbide

    Directory of Open Access Journals (Sweden)

    Kenneth Kanayo Alaneme

    2014-01-01

    Full Text Available The corrosion and wear behaviour of Al–Mg–Si alloy matrix hybrid composites developed with the use of rice husk ash (RHA and silicon carbide (SiC particulates as reinforcements were investigated. RHA and SiC mixed in weight ratios 0:1, 1:3, 1:1, 3:1, and 1:0 were utilized to prepare 5, 7.5 and 10 wt% of the reinforcing phase with Al Mg Si alloy as matrix using double stir casting process. Open circuit corrosion potential (OCP and potentiodynamic polarization measurements were used to study the corrosion behaviour while coefficient of friction was used to assess the wear behaviour of the composites. The corrosion and wear mechanisms were established with the aid of scanning electron microscopy. The results show that the effect of RHA/SiC weight ratio on the corrosion behaviour of the composites in 3.5% NaCl solution was not consistent for the different weight percent of reinforcement (5, 7.5, and 10 wt% used in developing the Al–Mg–Si based composites. It was evident that for most cases the use of hybrid reinforcement of RHA and SiC resulted in improved corrosion resistance of the composites in 3.5% NaCl solution. Preferential dissolution of the more anodic Al–Mg–Si alloy matrix around the Al–Mg–Si matrix/RHA/SiC particle interfaces was identified as the primary corrosion mechanism. The coefficient of friction and consequently the wear resistance of the hybrid composites were comparable to that of the Al–Mg–Si alloy matrix reinforced with only SiC.

  11. 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)

  12. H-ZSM-5 Zeolite Synthesis by Sourcing Silica from the Wheat Husk Ash: Characterization and Application as a Versatile Heterogeneous Catalyst in Organic Transformations including Some Multicomponent Reactions

    Directory of Open Access Journals (Sweden)

    Isak Rajjak Shaikh

    2015-01-01

    Full Text Available ZSM-5 zeolite was synthesized by sourcing silica from wheat husk ash and was converted into its protonated form following careful, conventionally accepted ion-exchange method and calcinations. The H-ZSM-5 zeolite (Si/Al ratio = 30 prepared was appropriately characterized by XRD, FT-IR, SEM, TEM, TG-DTA, CV, and so forth, and evaluated as recyclable catalyst in selective organic transformations including three- and four-component reactions. The catalytic activity of the zeolite sample supposedly relates to increased density of the accessible acid sites.

  13. 掺入稻壳灰的泡沫混凝土及其发展分析%Foam Concrete Mixed with Rice Husk Ash and its Development Analysis

    Institute of Scientific and Technical Information of China (English)

    杨康; 王德玲; 喻成成; 李书磊; 王贤根

    2014-01-01

    This paper firstly introduced the development, performance and application of foam concrete. Secondly the property of rice husk ash ( RHA) was discussed. RHA con_tains about 90% amorphous silica which has high pozzolanic ac_tivity. Thirdly the effect of RHA on foam concrete was dis_cussed. RHA can enhance the strength of foam concrete in later age and improve its durability, homogeneity and corrosion resist_ance. It also improves the pore structure of foam concrete, ther_mal insulation and sound absorption performance. Lastly, the development of foam concrete mixed with RHA was analyzed from following aspects: selecting and processing materials such as foa_ming agents, RHA and cement, improving producing process of foam concrete, reducing cost and environmental impact.%本文先介绍了泡沫混凝土的发展、性能与应用,然后介绍了稻壳灰的性质,稻壳灰中含有90%左右的无定形态的二氧化硅,具有火山灰活性;接着讨论了稻壳灰替代部分水泥对泡沫混凝土性质的影响。稻壳灰可增强泡沫混凝土的后期强度和抗渗、耐侵蚀性,改善泡沫混凝土的孔隙结构,增强保温隔热、隔音性。最后对掺入稻壳灰的泡沫混凝土的发展方向进行了分析,包括选择和处理材料如发泡剂、稻壳灰、水泥等;优化生产工艺;降低成本及减小环境影响。

  14. 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.

  15. Study on Prosee for Synthesis of Zeolite A from Rice Husk Ash by Hydrothermal Treatment%利用稻壳灰水热合成A型沸石的工艺研究

    Institute of Scientific and Technical Information of China (English)

    陈景茂; 吴晋沪; 王裕鑫

    2011-01-01

    [Objective]The study aimed to obtain the optimum conditions for the synthesis of zeolite A from the rice husk ash. [Method]The reaction temperature, alkali concn. , reagent silicon and aluminum ratio and reaction time in the synthesis of zeolite A from rice husk ash by the hydrothermal treatment were studied by hydrothermal method. [ Result] Under the conditions as the hydrothermal temperature of 100 ℃, NaOH concn. Of 2 mol/L, raw material silicon and aluminum ratio of 1.0 -2.0 and reaction time of 4 -6 h, the zeolite A with higher crystal-linity could be obtained. [ Conclusion ] The technology was simple and economical, and provided a new approach to the comprehensive utilization of bio-ash, which is in favour of achieving complete biomass energy utilization system and forming the sustainable development.%[目的]得出稻壳灰合成A型沸石的最佳条件.[方法]利用水热法对稻壳灰合成A型沸石的反应温度、碱浓度、反应物硅铝比和反应时间进行研究.[结果]在水热温度100℃,NaOH浓度为2 mol/L,原料硅铝比为1.0 ~2.0,反应时间为4~6h的条件下,可以得到结晶度较高的A型沸石.[结论]该方法工艺简单经济,为生物质灰的利用提供了一种思路,有利于实现完整的生物质能源利用系统,形成可持续发展.

  16. Screening of filamentous fungi to produce xylanase and xylooligosaccharides in submerged and solid-state cultivations on rice husk, soybean hull, and spent malt as substrates.

    Science.gov (United States)

    da Silva Menezes, Bruna; Rossi, Daniele Misturini; Ayub, Marco Antônio Záchia

    2017-03-01

    We investigated the enzymatic complex produced by selected fungi strains isolated from the environment using the agro-industrial residues rice husk, soybean hull, and spent malt as substrates. Microbial growth was carried out in solid-state cultivation (SSC) and in submerged cultivations (SC) and the enzymatic activities of xylanase, cellulase, β-xylosidase, and β-glucosidase were determined. All substrates were effective in inducing enzymatic activities, with one strain of Aspergillus brasiliensis BLf1 showing maximum activities for all enzymes, except for cellulases. Using this fungus, the enzymatic activities of xylanase, cellulase, and β-glucosidase were generally higher in SSC compared to SC, producing maxima activities of 120.5, 25.3 and 47.4 U g(-1) of dry substrate, respectively. β-xylosidase activity of 28.1 U g(-1) of dry substrate was highest in SC. Experimental design was carried out to optimize xylanase activity by A. brasiliensis BLf1 in SSC using rice husk as substrate, producing maximum xylanase activity 183.5 U g(-1) dry substrate, and xylooligosaccharides were produced and characterized. These results suggest A. brasiliensis BLf1 can be used to produce important lytic enzymes to be applied in the preparation of xylooligosaccharides.

  17. 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

  18. Use of rice husk ash as only source of silica in the formation of mesoporous materials Emprego da cinza da casca de arroz como única fonte de sílica na formação de materiais mesoporosos

    Directory of Open Access Journals (Sweden)

    A. J. Schwanke

    2013-03-01

    Full Text Available This paper reports the synthesis of molecular sieves similar to MCM-41 using rice husk ash as only source of silica. For comparison purposes, a standard synthesis was performed using aerosil 200 commercial silica. The rice husk silica was obtained by heating treatment at 600 ºC and leaching for 2 h in reflux with HCl 1mol.L-1 and used in the synthesis. The samples prepared were characterized by N2 adsorption, X-ray diffraction (XRD, scanning electronic microscopy (SEM and thermogravimetric analysis (TG. By type-IV adsorption isotherms, the formation of mesoporous materials was observed. XRD showed the formation of hexagonal unidirectional pore materials similar to MCM-41. By SEM, it could be observed that the rice husk has fibrous aspect and that synthesis using calcined and leached rice husk did not react entirely because silica was only partially dissolved.Este trabalho relata o estudo da síntese de peneiras moleculares semelhantes à MCM-41, empregando cinza da casca de arroz como única fonte de sílica. Para critérios de comparação uma síntese foi realizada com sílica comercial aerosil 200. A sílica da casca de arroz foi obtida mediante tratamento térmico a 600 ºC e lixiviação em refluxo por 2 h com HCl 1 mol/L e empregada na síntese. As amostras preparadas foram caracterizadas por adsorção de N2, difração de raios X, microscopia eletrônica de varredura (MEV e termogravimetria. Por meio das isotermas de adsorção, do tipo IV, observa-se a formação de material mesoporoso. Nos difratogramas de raios X é identificada a formação hexagonal unidirecional de poros, indicando que material apresenta semelhanças com a MCM-41. Por MEV observa-se que a casca de arroz possui aspecto fibroso e que a síntese empregando a casca de arroz calcinada e lixiviada não reagiu na sua totalidade devido a dissolução parcial da sílica.

  19. Characterisation of ashes produced by co-combustion of recovered fuels and peat

    Energy Technology Data Exchange (ETDEWEB)

    Frankenhaeuser, M. [Borealis Polymers Oy, Porvoo (Finland)

    1997-10-01

    The current project focuses on eventual changes in ash characteristics during co-combustion of refuse derived fuel with coal, peat, wood or bark, which could lead to slagging, fouling and corrosion in the boiler. Ashes were produced at fluidised bed (FB) combustion conditions in the 15 kW reactor at VTT Energy, Jyvaeskylae, the fly ash captured by the cyclone was further analysed by XRF at Outokumpu Geotechnical Laboratory, Outokumpu. The sintering behaviour of these ashes was investigated using a test procedure developed at the Combustion Chemistry Research Group at Aabo Akademi University. The current extended programme includes a Danish refuse-derived fuel (RDF), co-combusted with bark/coal (5 tests) and wood/coal (2 tests), a RF from Jyvaskyla (2 tests with peat/coal) and de-inking sludges co- combusted at full-scale with wood waste or paper mill sludge (4 ashes provided by IVO Power). Ash pellets were thermally treated in nitrogen in order to avoid residual carbon combustion. The results obtained show no sintering tendencies below 600 deg C, significant changes in sintering are seen with pellets treated at 1000 deg C. Ash from 100 % RDF combustion does not sinter, 25 % RDF co-combustion with wood and peat, respectively, gives an insignificant effect. The most severe sintering occurs during co-combustion of RDF with bark. Contrary to the earlier hypothesis a 25 % coal addition seems to have a negative effect on all fuel blends. Analysis of the sintering results versus ash chemical composition shows, that (again), in general, an increased level of alkali chlorides and sulphates gives increased sintering. Finally, some results on sintering tendency measurements on ashes from full-scale CFB co-combustion of deinking sludge with wood waste and paper mill sludge are given. This shows that these ashes show very little, if any, sintering tendency, which can be explained from ash chemistry

  20. Properties of High Volume Fraction Fly Ash/Al Alloy Composites Produced by Infiltration Process

    Science.gov (United States)

    Kountouras, D. T.; Stergioudi, F.; Tsouknidas, A.; Vogiatzis, C. A.; Skolianos, S. M.

    2015-09-01

    In the present study, pressure infiltration is employed to synthesize aluminum alloy 7075-fly ash composites. The microstructure and chemical composition of the fly ash and the produced composite material was examined using optical and scanning electron microscopy, as well as x-ray diffraction. Several properties of the produced composite material were examined and evaluated including macro-hardness, wear, thermal expansion, and corrosion behavior. The wear characteristics of the composite, in the as-cast conditions, were studied by dry sliding wear tests. The corrosion behavior of composite material was evaluated by means of potentiodynamic corrosion experiments in a 3.5 wt.% NaCl solution. The composite specimens exhibit a homogeneous distribution of fly ash particles and present enhanced hardness values, compared to the matrix material. The high volume fraction of the fly ash reinforcement (>40%) in the composite material led to increased wear rates, attributed to the fragmentation of the fly ash particles. However, the presence of fly ash particles in the Al alloy matrix considerably decreased the coefficiency of thermal expansion, while resulting in an altered corrosion mechanism of the composite material with respect to the matrix alloy.

  1. 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 %.

  2. Measures for reducing pollution produced by ash spoil banks of thermoelectric stations, by biological recultivation

    Directory of Open Access Journals (Sweden)

    MAXIM A.

    2008-11-01

    Full Text Available Worldwide, the thermoelectric power stations produce 70% from the total of electric energy. This intenselypollutes all environment compartments. The thermoelectric power stations produce as much gaseous (CO, CO2,NOx, SOx as solid (ash and heavy metals pollutants. Ash spoil banks from Romania occupy 3102 hectares. Themost efficient measure of rehabilitation is biological recultivation (agricultural, forestry, agricultural continuedby forest. The world and national researches on this domain shows that forest recultivation is the mostadvantageous, because requires a minimum of works towards agricultural recultivation, improves the locallandscape and contributes to the restore in circuit a part from total carbon emission mass of thermoelectric powerstation.

  3. Chemical composition of overland flow produced on soils covered with vegetative ash

    Directory of Open Access Journals (Sweden)

    M.B. Bodí

    2013-05-01

    Full Text Available The objective of this study was to ascertain the differences between the soluble elements of ash obtained under laboratory conditions and the dissolved in overland flow from soils covered with a layer of ash. The overland flow was obtained during series of rainfall simulations over soils covered with two different types of ash. This study indicates that the soluble elements released from ash can modify water quality increasing its pH, electrical conductivity and especially cation content. The nutrients solubilised are not necessarily the same as the elemental composition of ash itself. Runoff composition depends on the volume of water produced, on the solubility of the ash components and on the chemical interactions with water from rainfall and soil. After the first intense rain event, most of the elements are solubilised and lixiviated or washed out, however, some of them may increase in the runoff or soil water some weeks later due to chemical interactions with water from rainfall and soil nutrients.

  4. Characterization of Coconut Shell Ash for Potential Utilization in Metal Matrix Composites for Automotive Applications.

    Directory of Open Access Journals (Sweden)

    P.B Madakson

    2012-03-01

    Full Text Available Coconut shell ash is agricultural waste. The waste is produced in abundance globally and poses risk to health as well as environment. Thus their effective, conducive and eco-friendly utilization has always been a challenge for scientific applications. This paper mainly deals with identification of characteristics of coconutshell ash using spectroscopic and microscopic analysis. Density, Particle size, Refractoriness, SEM, XRD,XRF and FTIR spectroscopic methods were used for the characterization of the coconut shell ash. The results were compared and it was observed that the ash possesses nearly same chemical phases and other functional groups as reinforcement like fly ash, rice husk ash, bagasse ash that have been in Metal Matrix Composites (MMCs specifically for automobile applications. Hence, coconut shell ash can be used as a low costreinforcement in Metal Matrix Composites (MMCs.

  5. Extraction of Silica and other related products from Rice Husk

    OpenAIRE

    Abhishek Mehta,; Dr. R. P Ugwekar

    2015-01-01

    The main objective of the present work is the synthesis of silica from rice husk and to study its characterization studies. The alkaline method succeeded by acid precipitation is done for the extraction of silica. The optimization of the concentration of sodium hydroxide and the amount of rice husk ash that goes with it for attaining the maximum yield of silica is done. X-ray Diffraction and Fourier Transform Infrared Spectrometry studies are executed for acquiring its characteris...

  6. USABILITY OF RICE HUSKS lN'TIlE'PRODUCTION/OF ROOFING ...

    African Journals Online (AJOL)

    husk To carry out the study, the researcher used risk husk, cement, waste paper and ... treatment. The samples produced were tested for water absorption, water ... I conventional building materials, efforts have been directed towards the local ...

  7. Use of disposed waste ash from landfills to replace Portland cement.

    Science.gov (United States)

    Rukzon, Sumrerng; Chindaprasirt, Prinya

    2009-09-01

    In this study, waste ash was utilized as a pozzolanic material in blended Portland cement in order to reduce negative environmental effects and landfill volume required to dispose of waste ash. The influence of waste ash, namely palm oil fuel ash, rice husk ash and fly ash on compressive strength and sulfate resistance in mortar were studied and evaluated by some accelerated short-term techniques in sodium sulfate solutions. Ordinary Portland cement (OPC) was partially replaced with ground palm oil fuel ash (POA), ground rice husk ash (RHA) and classified fly ash (FA). Single pozzolan and a blend of equal weight portions of POA, RHA and FA were also used. The resistance to sulfate attack of mortar improves substantially with partial replacement of OPC with POA, RHA and FA. The use of a blend of equal weight portions of FA and POA or RHA produced mixes with good strength and resistance to sulfate attack. POA, RHA and FA have a high potential to be used as a pozzolanic material.

  8. Triboelectrostatic Separation-an Efficient Method of Producing Low Ash Clean Coal

    Institute of Scientific and Technical Information of China (English)

    章新喜; 边炳鑫; 段超红; 熊建军

    2002-01-01

    At present, coal is mainly consumed as fuel. In fact, coal is also a kind of precious raw material in chemical industry on the premise that some harmful minerals should be removed from coal. The paper presents the results of the research on producing low ash (<2%) coal with triboelectrostatic separator used for producing high-grade active carbon. The test is conducted in bench-scale system, whose capacity is 30~100 kg/h. The results indicate that: 1) the ash content of clean coal increases with the increase of solid content of feedstock, on the contrary, the yield of clean coal is declining; 2) a high velocity may result in a good separation efficiency; 3) for the same solid content, the reunion caused by intermolecular force makes the separation efficiency drop down when the ultra-fine coal is separated; 4) the separation efficiency is improved with the increase of electric field intensity, but there is a good optimized match between the electric field intensity and yield of clean coal; 5) a low rank coal is easy-to-wash in triboelectrostatic separation process; 6) the yield of clean coal can be enhanced and the ash decreased through adapting optimized conditions according to various coals.

  9. 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

  10. 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.

  11. 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.

  12. 电厂废弃稻壳灰水热合成ZSM-5分子筛%Hydrothermal synthesis of ZSM-5 zeolite from rice husk ash in power plant

    Institute of Scientific and Technical Information of China (English)

    张超; 郎林; 阴秀丽; 吴创之

    2012-01-01

    The rice husk ash collected from biomass power plants was reacted with KOH solution to obtain silica sol, which was used to synthesize ZSM-5 zeolite by hydrothermal crystallization. The effects of KOH solution concentration, reaction temperature, and reaction time on the Si dissolving rate were investigated, and the optimum parameters of alkali dissolution were obtained. The effects of template contentrations and Si/Al molar ratio on the synthesis of ZSM -5 zeolite in the complex system were also studied. The as-synthesized samples were characterized by XRD, SEM, ICP, TG-DSC and BET. The results show that the ZSM-5 crystals could be successfully synthesized in a wide range of the Si/Al molar ratio (15~2002), and the products (30≤Si/Al≤52002)had complete crystal shape, high thermal stability, large specific surface area, and its micropore size was centered at about 0.53 nm.%以电厂废弃稻壳灰为原料,通过KOH溶液水热处理制取硅溶胶,采用水热合成法制备ZSM-5分子筛.考察了KOH溶液浓度、反应温度和反应时间对Si溶出率的影响,探索出最佳碱溶工艺条件;研究了在复杂合成体系中,模板剂用量、Si/Al等因素对ZSM-5分子筛合成过程的影响;采用XRD,SEM,ICP,TG-DSC,N2吸附脱附等手段进行表征,结果表明,以电厂废弃稻壳灰为原料,在较宽Si/Al范围内(15~2002)均可合成出ZSM-5分子筛;当Si/Al为30~2002时,分子筛产物晶形较为完备,热稳定性好,比表面积较大,微孔分布集中于0.53 nm.

  13. Incorporation of hazelnut shell and husk in MDF production.

    Science.gov (United States)

    Cöpür, Yalçin; Güler, Cengiz; Taşçioğlu, Cihat; Tozluoğlu, Ayhan

    2008-10-01

    Hazelnut shell and husk (Coryllus arellana L.) is an abundant agricultural residue in Turkey and investigating the possibilities of utilizing husk and shell in panel production might help to overcome the raw material shortage that the panel industry is facing. The aim of this work was to investigate the possibilities of utilizing hazelnut shell and husk in medium density fiberboard (MDF) production. To produce general purpose fiberboards, fiber-husk and fiber-shell mixtures at various percentages were examined in this study. The results indicated that panels could be produced utilizing hazelnut husk up to 20% addition without falling below the properties required in the standards. Shell addition was restricted up to 10%, because higher addition levels diminished the elastic modulus and internal bond strength below the acceptable level.

  14. 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

  15. Extraction of Silica and other related products from Rice Husk

    Directory of Open Access Journals (Sweden)

    Abhishek Mehta,

    2015-08-01

    Full Text Available The main objective of the present work is the synthesis of silica from rice husk and to study its characterization studies. The alkaline method succeeded by acid precipitation is done for the extraction of silica. The optimization of the concentration of sodium hydroxide and the amount of rice husk ash that goes with it for attaining the maximum yield of silica is done. X-ray Diffraction and Fourier Transform Infrared Spectrometry studies are executed for acquiring its characteristic. Activated carbon and silica gel are the intermediate products formed during the synthesis process of silica.

  16. Chemical properties of urban waste ash produced by open burning on the Jos Plateau: implications for agriculture.

    Science.gov (United States)

    Pasquini, M W; Alexander, M J

    2004-02-05

    Urban centres produce most of the world's waste and between a third and a half goes uncollected. The answer to the problem of waste disposal lies partly in agriculture, as waste can be extremely nutrient-rich. In the last decade there has been a tremendous increase in the developing world in total city area under informal food production and there are many examples of waste recycling onto the urban or peri-urban plots. Farmers on the Jos Plateau, Nigeria, have developed a successful soil fertility management strategy based on the combination of inorganic fertilisers, manure and urban waste ash. This study sought to provide some preliminary data on urban waste ash produced by open burning and used in farming in a developing country. Ash samples were collected from different locations around Jos and tested for C, N, pH, P, Na, K, Ca, Mg, Fe, Mn, Zn, Cu, Ni, Cd and Pb. It was found that ash is an effective liming material (because of the high pH, and high Ca, Mg and K contents), and has the potential to contribute significant quantities of micro-nutrients such as Mn, Zn and Cu. Ash, however, is far from being a homogenous material and its variability means that its fertilising potential will vary between batches and that, even if mean and median levels are low, there is the risk of the formation of localised areas of soil with excessive heavy metal contents (this is particularly the case with Pb). Further research is required to determine the plant-availability of these elements in the ash and to assess the wider environmental and health implications of uncontrolled, open burning of waste as a means of producing ash for agricultural purposes.

  17. Micro Fine Sized Palm Oil Fuel Ash Produced Using a Wind Tunnel Production System

    Directory of Open Access Journals (Sweden)

    R. Ahmadi

    2016-01-01

    Full Text Available Micro fine sized palm oil fuel ash (POFA is a new supplementary cementitious material that can increase the strength, durability, and workability of concrete. However, production of this material incurs high cost and is not practical for the construction industry. This paper investigates a simple methodology of producing micro fine sized POFA by means of a laboratory scale wind tunnel system. The raw POFA obtained from an oil palm factory is first calcined to remove carbon residue and then grinded in Los Angeles abrasion machine. The grinded POFA is then blown in the fabricated wind tunnel system for separation into different ranges of particle sizes. The physical, morphological, and chemical properties of the micro fine sized POFA were then investigated using Laser Particle Size Analyser (PSA, nitrogen sorption, and Scanning Electron Microscopy with Energy Dispersive X-Ray (SEM-EDX. A total of 32.1% micro fine sized POFA were collected from each sample blown, with the size range of 1–10 micrometers. The devised laboratory scale of wind tunnel production system is successful in producing micro fine sized POFA and, with modifications, this system is envisaged applicable to be used to commercialize micro fine sized POFA production for the construction industry.

  18. Degradation of Al/SiCp composites produced with rice-hull ash and aluminum cans.

    Science.gov (United States)

    Escalera-Lozano, R; Gutiérrez, C A; Pech-Canul, M A; Pech-Canul, M I

    2008-01-01

    The use of recycling aluminum from beverage containers and rice-hull ash (RHA) offers to be an attractive alternative for the economic production of Al/SiCp composites. However, corrosion phenomena in the composites represent technological barriers yet to be resolved before they can be exploited to their full potential. A simple methodology involving characterization by XRD, SEM, EDX, FTIR and ICP was designed in order to investigate the causes of the rapid degradation in a humid environment of Al/SiCp composites produced with RHA and aluminum cans. Results reveal that the use of RHA was beneficial to avoid degradation through the formation and subsequent hydration of the Al4C3 phase. However with condensed moisture acting as an electrolyte, localized corrosion took place with aggressive damage manifested by the disintegration of the composite into a powdery mixture. The relevant corrosion mechanism was mainly attributed to microgalvanic coupling between the Mg2Si intermetallic compound and the matrix (although other phases such as SiC, Si, MgAl2O4 could also work as microcathodes).

  19. Immobilization of trace elements in municipal solid waste incinerator (MSWI) fly ash by producing calcium sulphoaluminate cement after carbonation and washing.

    Science.gov (United States)

    Wang, Lei; Jamro, Imtiaz Ali; Chen, Qi; Li, Shaobai; Luan, Jingde; Yang, Tianhua

    2016-03-01

    The possibility of producing calcium sulphoaluminate cement (CSA) by adding municipal solid waste incinerator (MSWI) fly ash to raw meal was investigated. After subjecting MSWI fly ash to accelerated carbonation and washing with water (ACW), various amounts (i.e., 5, 10 and 15 wt%) of the treated ash were added to raw meal composed of a mixture of bauxite, limestone and gypsum. The mixtures were sintered in a laboratory-scale muffle furnace at temperatures of 1250°, 1300°, 1325° and 1350 °C for various durations. The influence of different quantities of MSWI fly ash on the mineralogy, major phase composition and strength development of the resulting clinker was studied, as was the effect of ash treatments on leaching and volatilization of trace elements. The ACW treatment reduced the volatilization ratio of trace elements during the clinkerization process. Volatilization ratios for lead, cadmium and zinc were 21.5%, 33.6% and 16.3%, respectively, from the ACW fly ash treatment, compared with ratios of 97.5%, 93.1% and 85.2% from untreated fly ash. The volatilization ratios of trace elements were ordered as follows: untreated fly ash > carbonated fly ash > carbonated and water-washed fly ash. The ACW process also reduced the chloride content in the MSWI fly ash by 90 wt% and prevented high concentrations of trace elements in the effluents.

  20. Coconut husk-fueled pilot plant put to test

    Energy Technology Data Exchange (ETDEWEB)

    1979-10-01

    A pilot electric-power plant, running on coconut husks, was successfully demonstrated in Laguna, Philippines. This 30-kW biomass-fed plant provides electricity for 50 remote households and a wood-carving shop using a motor. The system involves: burning coconut husks to obtain producer gas; filtering this gas and driving a generator with the power of the combusted gas. The village is saving 65 to 75% of their diesel fuel consumption with this system.

  1. Instillation of coarse ash particulate matter and lipopolysaccharide produces a systemic inflammatory response in mice

    Energy Technology Data Exchange (ETDEWEB)

    Finnerty, K.; Choi, J.E.; Lau, A.; Davis-Gorman, G.; Diven, C.; Seaver, N.; Linak, W.P.; Witten, M.; McDonagh, P.F. [Arizona Health Science Center, Tucson, AZ (United States)

    2007-07-01

    Coronary ischemic events increase significantly following a 'bad air' day. Ambient particulate matter (PM10) is the pollutant most strongly associated with these events. PM10 produces inflammatory injury to the lower airways. It is not clear, however, whether pulmonary inflammation translates to a systemic response. Lipopolysaccharide (LPS) is a proinflammatory molecule often associated with the coarse fraction of PM. It was hypothesized that PM > 2.5 from coal plus LPS induce pulmonary inflammation leading to a systemic inflammatory response. Mice were intratracheally instilled with saline, PM (200 {mu} g), PM+ LPS10 (PM+ 10 {mu} g LPS), or PM+ LPS100 (PM+ 100 {mu} g LPS). Eighteen hours later, histologic analysis was performed on lungs from each group. Pulmonary and systemic inflammation were assessed by measuring the proinflammatory cytokines tumor necrosis factor (TNF)-{alpha} and interleukin (IL)-6 in the pulmonary supernatant and plasma. In a follow-up study, the effects of LPS alone were assessed. Histologic analysis revealed a dose-dependent elevation in pulmonary inflammation with all treatments. Pulmonary TNF-{alpha} and IL-6 both increased significantly with PM+ LPS100 treatment. Regarding plasma, TNF-{alpha} significantly increased in both PM+ LPS10 and PM+ LPS100 treatments. For plasma IL-6, all groups tended to rise with a significant increase in the PM+ LPS100 group. The results of the follow-up study indicate that the responses to PM+ LPS were not due to LPS alone. These results suggest that coarse coal fly ash PM > 2.5 combined with LPS produced pulmonary and systemic inflammatory responses. The resulting low-level systemic inflammation may contribute to the increased severity of ischemic heart disease observed immediately following a bad air day.

  2. Recycling of ash from biomass incinerator in clay matrix to produce ceramic bricks.

    Science.gov (United States)

    Pérez-Villarejo, L; Eliche-Quesada, D; Iglesias-Godino, Fco J; Martínez-García, C; Corpas-Iglesias, Fco A

    2012-03-01

    The objective of this study is to investigate the effect of incorporation of ash from biomass incinerator as raw material on the production of ceramic bricks for their application in construction. So, for the fabrication of bricks, compositions were prepared with addition of increasing amounts of waste ash (0%, 10%, 20%, 30%, 40% and 50% in wt.) in the clay body. The mixed samples were sintered using conventional powder processing based on powder compaction at 54.5 MPa and firing them at 950 °C without the addition of additives. Effect on apparent density, water absorption and mechanical properties were investigated. The results showed that water absorption increased and apparent density and compressive strength decreased with higher amounts of ash. Bricks with an ash content up to 20% meet the UNE standards compressive strength. As a result, since interesting performances were observed, the potential use of ashes from biomass incinerator up to 20 wt.% in ceramic formulations of industrial interest was confirmed. In this sense, incorporating ashes into clay body reduces environmental problems and total cost of raw material disposition. Copyright © 2010. Published by Elsevier Ltd.

  3. Microstructure characteristic and X-ray energy dispersive microanalysis of combustion ash of rice husk and rice straw%稻壳与稻秆灼烧灰颗粒的微观形态特征及其能谱分析

    Institute of Scientific and Technical Information of China (English)

    姚锡文; 许开立

    2015-01-01

    In the past decades, sustainable development and increasing fuel demand have necessitated the identification of possible energy sources. The utilization of biomass will reach up to 50 million tons in China after ten years. Nowadays, many countries are putting great emphasis on the exploration of biomass energy. The techniques used are various such as combustion, gasification, pyrolysis, hydrogen production. The use of the biomass as fuel generates a large amount of residual ash which causes serious environmental problems, as the biomass ash is easy to melt and volatilize. During the thermo-chemical conversion process, the residual inorganic materials also form the slag inside the boiler and the fly ash deposits on the tail heating surface, which retards heat transfer, deteriorates burning, and causes high temperature corrosion and super heat explosion. As one kind of clean and renewable energy, rice husk (RH) and rice straw (RS) are the main by-products during the process of rice processing. Especially, in comparison with other agricultural wastes, the ash content of RH is much higher. After thermo-chemical conversion, the inorganic mineral matters left are ashes, which can easily bond with tar and lead to the phenomenon of slagging, fouling and corrosion for the thermo-chemical conversion equipments. Therefore, in this study, the analysis of microstructure characteristics and elemental composition of these ashes from the combustion of RH and RS at 600℃ and 815℃ respectively was comprehensively conducted by using the scanning electron microscopy (SEM) and the energy dispersive X-ray microanalysis (EDX). The influence of ashing temperature on the particle size distribution, micromorphology, particle surface, interior structure and elemental composition of biomass ash was investigated. The results showed that the higher the ashing temperature was, the smaller the size of the ash would be. With the increase of ashing temperature, the distribution of ash was more

  4. Biotechnological potential of coffee pulp and coffee husk for bioprocesses.

    Science.gov (United States)

    Pandey; Soccol; Nigam; Brand; Mohan; Roussos

    2000-10-01

    Advances in industrial biotechnology offer potential opportunities for economic utilization of agro-industrial residues such as coffee pulp and coffee husk. Coffee pulp or husk is a fibrous mucilagenous material (sub-product) obtained during the processing of coffee cherries by wet or dry process, respectively. Coffee pulp/husk contains some amount of caffeine and tannins, which makes it toxic in nature, resulting the disposal problem. However, it is rich in organic nature, which makes it an ideal substrate for microbial processes for the production of value-added products. Several solutions and alternative uses of the coffee pulp and husk have been attempted. These include as fertilizers, livestock feed, compost, etc. However, these applications utilize only a fraction of available quantity and are not technically very efficient. Attempts have been made to detoxify it for improved application as feed, and to produce several products such as enzymes, organic acids, flavour and aroma compounds, and mushrooms, etc. from coffee pulp/husk. Solid state fermentation has been mostly employed for bioconversion processes. Factorial design experiments offer useful information for the process optimization. This paper reviews the developments on processes and products developed for the value-addition of coffee pulp/husk through the biotechnological means.

  5. An "Adventure" of MBA Students in Europe: How Volcanic Ash Produced an Incidental Learning Experience

    Science.gov (United States)

    Vazquez, Ana Claudia Souza; Ruas, Roberto Lima; Cervo, Clarissa S.; Hutz, Claudio Simon

    2013-01-01

    Because the volcanic ash that affected air travel in Western Europe in 2010 was considered as one of the most meaningful learning experiences by a group of MBA students, this article aims to outline the main aspects of an incidental learning situation, rarely described on management education literature. Incidental learning is an unsystematic…

  6. 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.

  7. 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.

  8. Processing of ash and slag waste of heating plants by arc plasma to produce construction materials and nanomodifiers

    Science.gov (United States)

    Buyantuev, S. L.; Urkhanova, L. A.; Kondratenko, A. S.; Shishulkin, S. Yu; Lkhasaranov, S. A.; Khmelev, A. B.

    2017-01-01

    The resultsare presented of plasma processing slag and ash waste from coal combustion in heating plants. Melting mechanism of ashand slagraw material is considered by an electromagnetic technological reactor. The analysis was conducted of temperature and phase transformations of raw material when it is heated up to the melting point, and also determination of specific energy consumption by using a generalized model of the thermodynamic analysis of TERRA. The study of materials melting temperature conditions and plum of melt was carried with high-temperature thermal imaging method, followed by mapping and 3D-modeling of the temperature fields. The investigations to establish the principal possibilities of using slag waste of local coal as raw material for the production of mineral (ash and slag) fibers found that by chemical composition there are oxides in the following ranges: 45-65% SiO2; 10-25% Al2O3; 10-45% CaO; 5-10% MgO; other minerals (less than 5%). Thus, these technological wastes are principally suitable for melts to produce mineral wool by the plasma method. An analysis of the results shows the melting point of ash and slag waste - 1800-2000 °C. In this case the specific energy consumption of these processes keeps within the limits of 1.1-1.3 kW*h/kg. For comparison it should be noted that the unit cost of electricity in the known high-melting industrial installations 5-6 kW*h/kg. Upon melting ash and slag waste, which contains up to 2-5% of unburned carbon, carbon nanomaterials were discovered.in the form of ultrafine soot accumulating as a plaque on the water-cooled surfaces in the gas cleaning chamber. The process of formation of soot consists in sublimation-desublimation of part of carbon which is in ash and slag, and graphite electrode. Thus, upon melting of ash and slag in the electromagnetic reactor it is possible to obtain melt, and in the subsequent mineral high quality fiber, which satisfies the requirements of normative documents, and

  9. 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 d

  10. Characterisation and management of ash produced in the hospital waste incinerator of Athens, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Kougemitrou, Irene [Harokopio University of Athens, 70 El. Venizelou Str., 17671 Athens (Greece); Godelitsas, Athanasios, E-mail: agodel@geol.uoa.gr [University of Athens, Panepistimioupoli Zographou, 15784 Athens (Greece); Tsabaris, Christos [Hellenic Center of Marine Research, 19013 Anavyssos (Greece); Stathopoulos, Vassilis [Technological Educational Institute of Chalkida, 34400 Psahna (Greece); Papandreou, Andreas [CERECO S.A. Ceramics and Refractories Technological Development Company, 34100 Chalkida (Greece); Gamaletsos, Platon [University of Athens, Panepistimioupoli Zographou, 15784 Athens (Greece); Economou, George [Institute of Geology and Mineral Exploration, Olympic Village, 13677 Acharnai (Greece); Papadopoulos, Dimitris [APOTEFROTIRAS S.A., Ano Liossia, 19200 Elefsina (Greece)

    2011-03-15

    Bottom and fly ash samples (BASH and FASH) from the APOTEFROTIRAS S.A. medical waste incinerator (Athens, Greece) were investigated. Powder-XRD data and geochemical diagrams showed BASH to be an amorphous material, analogous to basaltic glass, and FASH consisting of crystalline compounds (mainly CaClOH). Bulk analyses by ICP-MS and point analyses by SEM-EDS indicated a high content of heavy metals, such as Fe, Cu and Cr, in both samples. However, BASH was highly enriched in Ni while FASH was additionally enriched in Zn and Pb. Gamma-ray measurements showed that the radioactivity of both ash samples, due to natural and artificial radionuclides ({sup 137}Cs, {sup 57}Co), was within the permissible levels recommended by IAEA. According to EN-type leaching tests, BASH was practically inert with regard to the mobility of the hazardous elements in aqueous media. FASH, however, showed a relatively high EN (and TCLP) leachability with regard to Pb and Zn. Finally, the stabilisation method, suggested for the treatment of FASH, included compression of the powder into briquettes using an appropriate machine and embedding the briquettes into pozzolanic cement blocks. After this treatment, TCLP and EN-type tests showed minimal release of Pb and Zn, thereby demonstrating a reliable management of ash waste.

  11. Reducing Heavy Metal Element from Coal Bottom Ash by Using Citric Acid Leaching Treatment

    Directory of Open Access Journals (Sweden)

    Yahya Ahmad Asyari

    2017-01-01

    Full Text Available Coal ash is the residue that is produced during coal combustion for instance fly ash, bottom ash or boiler slag which was primarily produced from the combustion of coal. With growth in coal burning power station, huge amount of coal bottom ash (CBA considered as hazardous material which are normally disposed in an on-site disposal system without any commercialization purpose. Previous researchers have studied the extraction of silica from agricultural wastes such as palm ash and rice husk ash (RHA and CBA by using leaching treatment method. In this study, the weaker acid, citric acid solution was used to replace the strong acid in leaching treatment process. Result showed that the heavy metal content such as Copper (Cu, Zinc (Zn and Lead (Pb can be decrease. Meanwhile the silica can be extracted up to 44% from coal bottom ash using citric acid leaching treatment under the optimum reaction time of 60 minutes with solution temperature of 60°C and concentration of citric acid more than 2%.

  12. Prospects of using whole rice husk for the production of dense and ...

    African Journals Online (AJOL)

    user

    can be an excellent material for brick production thereby presenting a good alternative to OPC. Key words: .... ceramics from cement kiln dust and rice husk ash through ... brick properties. .... Nevertheless though many uses had ..... Solutions to Dearth of Affordable Housing,” Vanguard Mobile Edition, ... Concrete Structures.

  13. 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.

  14. Direct identification of hazardous elements in ultra-fine and nanominerals from coal fly ash produced during diesel co-firing.

    Science.gov (United States)

    Martinello, Kátia; Oliveira, Marcos L S; Molossi, Fernando A; Ramos, Claudete G; Teixeira, Elba C; Kautzmann, Rubens M; Silva, Luis F O

    2014-02-01

    This study has provided an initial assessment of the environmental impacts and potential health effects associated with coal fly ash produced during diesel co-firing. Many hazardous elements that are typically detected by multifaceted chemical characterization by XRD, petrology, FE-SEM/EDS, and HR-TEM/SEAD/FFT/EDS in ultra-fine compounds and nanominerals from the co-fired coal fly ashes (CFAs). It provided an in-depth understanding of coal ash produced during diesel co-firing. Several of the neoformed ultra-fine compounds and nano-minerals found in the coal ashes are the same as those commonly associated with oxidation/transformation of aluminosilicates, carbonates, sulphides and phosphates.

  15. Quick monitoring of pozzolanic reactivity of waste ashes.

    Science.gov (United States)

    Sinthaworn, Suppachai; Nimityongskul, Pichai

    2009-05-01

    This article proposes a quick method of monitoring for pozzolanic reactivity of waste ashes by investigating the electrical conductivity of the suspension at an elevated temperature. This suspension is obtained by mixing tested pozzolan with an ordinary Portland cement (OPC) solution produced by mixing ordinary Portland cement with water. For comparison, silica fume, metakaolin, rice husk ash and river sand - whose pozzolanic reactivities range from reactive to inert - were used in the experimental investigation. The electrical conductivity of the suspension was continually recorded by using an electrical conductivity meter and stored by using a personal computer for a period of slightly over 1day. The indicative parameters that can be related to pozzolanic reactivity were discussed and analyzed in detail. It was found that it is possible to determine the pozzolanic reactivity of fly ash within 28h by using the proposed technique, as compared to 7 or 28 days for the determination of strength activity index according to ASTM. This technique would help concrete technologists to speedily investigate the quality of fly ash for use as a cement replacement in order to alleviate pollution caused by cement production and solve disposal problems of waste ashes.

  16. Stabilization/solidification of fly ashes and concrete production from bottom and circulating ashes produced in a power plant working under mono and co-combustion conditions.

    Science.gov (United States)

    Barbosa, Rui; Lapa, Nuno; Lopes, Helena; Gulyurtlu, Ibrahim; Mendes, Benilde

    2011-01-01

    Two combustion tests were performed in a fluidized bed combustor of a thermo-electric power plant: (1) combustion of coal; (2) co-combustion of coal (68.7% w/w), sewage sludge (9.2% w/w) and meat and bone meal (MBM) (22.1% w/w). Three samples of ashes (bottom, circulating and fly ashes) were collected in each combustion test. The ashes were submitted to the following assays: (a) evaluation of the leaching behaviour; (b) stabilization/solidification of fly ashes and evaluation of the leaching behaviour of the stabilized/solidified (s/s) materials; (c) production of concrete from bottom and circulating ashes. The eluates of all materials were submitted to chemical and ecotoxicological characterizations. The crude ashes have shown similar chemical and ecotoxicological properties. The s/s materials have presented compressive strengths between 25 and 40 MPa, low emission levels of metals through leaching and were classified as non-hazardous materials. The formulations of concrete have presented compressive strengths between 12 and 24 MPa. According to the Dutch Building Materials Decree, some concrete formulations can be used in both scenarios of limited moistening and without insulation, and with permanent moistening and with insulation.

  17. Microbially-enhanced composting of wet olive husks.

    Science.gov (United States)

    Echeverria, M C; Cardelli, R; Bedini, S; Colombini, A; Incrocci, L; Castagna, A; Agnolucci, M; Cristani, C; Ranieri, A; Saviozzi, A; Nuti, M

    2012-01-01

    The production of a compost from olive wet husks is described. The process is enhanced through the use of starters prepared with virgin husks enriched with selected microbial cultures. This approach, with respect to composting without the use of starters, allows to achieve faster start of the process (10 vs. 45 days), deeper humification (humification rate 19.2 vs. 12.2), shorter maturation time (2 vs. 4-5 months) and better detoxification of the starting material. Furthermore, the compost produced can effectively substitute for turf as a cultivation substrate in horticulture at greenhouse level, with beneficial effects on nutraceutical traits of tomato fruits.

  18. Studies in an atmospheric bubbling fluidized-bed combustor of 10 MW power plant based on rice husk

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Ravi Inder [Department of Mechanical Engineering, Guru Nanak Dev Engineering College, Ludhiana, Punjab 141 006 (India); Mohapatra, S.K. [Department of Mechanical Engineering, Thapar University, Patiala, Punjab (India); Gangacharyulu, D. [Department of Chemical Engineering, Thapar University, Patiala, Punjab (India)

    2008-11-15

    In this paper an experience, environmental assessment, a model for exit gas composition, agglomeration problem and a model for solid population balance of 10 MW power plant at Jalkheri, Distt. Fatehgarh Sahib, Punjab, India based on rice husk has been discussed. Three phase multistage mathematical model for exit gas composition of rice husk in fluidized bed has been derived. The model is based on three-phase theory of fluidization and material balance for shrinking rice husk particles and it is similar to model developed by Kunii and Levenspiel. The burning of rice husk is assumed to take place according to single film theory. The model has been used to predict the exit gas composition particularly O{sub 2}, CO{sub 2} and N{sub 2}. The agglomeration problem of above plant which is main reason for defluidization of bed has also been discussed. SEM of ash agglomerates has been done. Ash samples taken from the above 10 MW power plant at Jalkheri has been quantitatively analyzed. Finally solid population model has been formed to calculate bed carbon load and carbon utilization efficiency. Above two models are experimentally correlated with the data collected from the above 10 MW power plant at Jalkheri, Distt. Fatehgarh Sahib, Punjab, India which uses rice husk as a fuel input (at the time of study). All the results from the model for rice husk are coming with in permissible limits. (author)

  19. Freeze-Thaw Resistance of Normal and High Strength Concretes Produced with Fly Ash and Silica Fume

    Directory of Open Access Journals (Sweden)

    Cenk Karakurt

    2015-01-01

    Full Text Available This study is based on determination of the freeze-thaw resistance of air-entrained and non-air-entrained normal strength concrete (NC and high strength concrete (HSC produced with fly ash and silica fume according to surface scaling. The procedure allows us to measure the amount of scaling per unit surface area due to a number of well defined freezing and thawing cycles in the presence of deicing salt. The weight loss, surface scaling, moisture uptake, and internal damage were measured after 0 and after every 4th freeze-thaw cycle. The test results showed that the freeze-thaw resistance is influenced directly by the compressive strength property of the concrete. Silica fume significantly reduced the resistance of normal strength concrete against freeze-thaw effect without plasticizing agent. The surface scaling of silica fume concrete without admixture was 22% higher than reference normal concrete.

  20. Analysis of the influence of fusion synthesis parameters on the SO2 sorption properties of zeolites produced out of fly ash

    Directory of Open Access Journals (Sweden)

    Czuma Natalia

    2016-01-01

    Full Text Available Fly ash zeolites are interesting alternative for zeolies produced out of pure chemicals as well as for natural zeolites. It can be applied as SO2 sorbents out of flue gases. In the work the experiments were aimed at investigation of SO2 sorption capacity of samples produced out of fly ash in fusion process. The influence of fusion reaction parameters on the type of obtained zeolites and on the efficiency of synthesis was investigated. The samples containing the same types of zeolites, but with different production yield were testes on SO2 sorption capacity.

  1. 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.

  2. 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.

  3. Degradation of caffeine by microorganisms and potential use of decaffeinated coffee husk and pulp in animal feeding

    Directory of Open Access Journals (Sweden)

    Mazzafera Paulo

    2002-01-01

    Full Text Available Coffee husk and coffee pulp are coffee processing by-products. Coffee husk is obtained when harvested coffee is processed by the dry method, and coffee pulp is produced by the wet method. In Brazil, coffee is usually processed by the dry method, therefore an expressive amount of husk is obtained every year. Some of the husk is used as organic fertilizer but, other applications are very limited, mainly because it is a bulky product. The presence of tannins and caffeine diminish acceptability and palatability of husk by animals. This review discuss degradation of caffeine by microorganisms, with special attention to bacterial, biological decaffeination of coffee husk and pulp and its subsequent use on animal feeding. The known biochemical routes of caffeine degradation by microorganisms are initially discussed; problems concerning physiological effects in animals, focusing on the limitations imposed by caffeine as an antiphysiological component are raised; the use of microorganisms to decaffeinate coffee husk and pulp is discussed. The discussions offer a view on decreasing caffeine content of coffee husk and pulp, which would allow the use of larger amounts of these products in animal feeding, partially replacing traditional components such as cereal grains.

  4. 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.

  5. Comparison of Ash from PF and CFB Boilers and Behaviour of Ash in Ash Fields

    Science.gov (United States)

    Arro, H.; Pihu, T.; Prikk, A.; Rootamm, R.; Konist, A.

    Over 90% of electricity produced in Estonia is made by power plants firing local oil shale and 25% of the boilers are of the circulating fluidised bed (CFB) variety. In 2007 approximately 6.5 million tons of ash was acquired as a byproduct of using oil shale for energy production. Approximately 1.5 million tons of that was ash from CFB boilers. Such ash is deposited in ash fields by means ofhydro ash removal.

  6. Feasibility of ethanol production from coffee husks.

    Science.gov (United States)

    Gouvea, B M; Torres, C; Franca, A S; Oliveira, L S; Oliveira, E S

    2009-09-01

    The objective of this work was to evaluate the feasibility of ethanol production by fermentation of coffee husks by Saccharomyces cerevisiae. Batch fermentation studies were performed employing whole and ground coffee husks, and aqueous extract from ground coffee husks. It was observed that fermentation yield decreased with an increase in yeast concentration. The best results were obtained for the following conditions: whole coffee husks, 3 g yeast/l substrate, temperature of 30 degrees C. Under these conditions ethanol production was 8.49 +/- 0.29 g/100 g dry basis (13.6 +/- 0.5 g ethanol/l), a satisfactory value in comparison to literature data for other residues such as corn stalks, barley straw and hydrolyzed wheat stillage (5-11 g ethanol/l). Such results indicate that coffee husks present excellent potential for residue-based ethanol production.

  7. Soil application of ash produced by low-temperature fluidized bed gasification: effects on soil nutrient dynamics and crop response

    DEFF Research Database (Denmark)

    Müller-Stöver, Dorette Sophie; Ahrenfeldt, Jesper; Holm, Jens Kai

    2012-01-01

    Recycling of residual products of bioenergy conversion processes is important for adding value to the technologies and as a potential beneficial soil fertility amendment. In this study, two different ash materials originating from low temperature circulating fluidized bed (LT-CFB) gasification...... of either wheat straw (SA) or residue fibers mainly from citrus peels (CP) were tested regarding their potential to be used as fertilizer on agricultural soils. A soil incubation study, a greenhouse experiment with barley and faba bean, and an accompanying outdoor experiment with maize were carried out...... to investigate the effects of the ashes on soil microbiological and chemical properties and on the response of the three crops. The ash treatments were compared with a control treatment that received only nitrogen, magnesium, and sulphur (CO) and a fully fertilized control (COPK). Soil microbial parameters were...

  8. Development of Briquette from Coir Dust and Rice Husk Blend: An Alternative Energy Source

    Directory of Open Access Journals (Sweden)

    Md. Hamidul Islam

    2014-05-01

    Full Text Available Biomass is one of the predominant renewable energy sources and the use of biomass for the energy generation has got much attention due to its environmental friendliness. Densification of coir dust into fuel briquette can solve waste disposal problem as well as can serve as an alternative energy source. The objective of this study was to investigate the possibility of producing briquette from coir dust and rice husk blend without binder. During this study, a briquetting experiment was conducted with different coir dust and rice husk blends (i.e. coir dust and rice husk ratio of 80:20, 60:40, 50:50, 40:60, 20:80 and 0:100. Briquetting operation was performed using a die-screw press type briquetting machine. The briquettes were tested to evaluate their density, compressive strength, calorific value, burning rate and water vaporizing capacity and it was found that mixing ratio had a significant effect on the physical, mechanical and combustion properties of the coir dust-rice husk briquettes. Density, compressive strength and calorific value and water vaporizing capacity were increased with increasing mixing ratio while burning rate was decreased. Coir dust-rice husk briquettes with mixing ratio of 20:80 had higher density (1.413 g/cm3, compressive strength (218.4 N/cm2, calorific value (4879 kcal/kg, water vaporizing capacity (0.853 l/kg and low burning rate (0.783 kg/hour followed by the mixing ratio 40:60, 50:50, 60:40 and 0:100. The results indicate that coir dust and rice husk blend briquettes were found to have better overall handling characteristics over rice husk briquette. However, production of briquettes from coir dust and rice husk at mixing ratio of 50:50 was found to be more suitable for commercial application in terms of cost effectiveness.

  9. 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.

  10. Medium-density particleboards from modified rice husks and soybean protein concentrate-based adhesives.

    Science.gov (United States)

    Ciannamea, Emiliano M; Stefani, Pablo M; Ruseckaite, Roxana A

    2010-01-01

    The main goal of this work was to evaluate the technical feasibility of using rice husk (RH) as wood substitute in the production of environmentally sound medium-density particleboards using adhesives from soybean protein concentrate (SPC). Chemical modification of rice husk with sodium hydroxide and sodium hydroxide followed by hydrogen peroxide (bleaching) were undertaken to evaluate the effect of such treatments on the composition and topology of rice husk and the performance of produced panels. Both treatments were efficient in partially eliminating hemicelluloses, lignin and silica from RH, as evidenced by thermo-gravimetric analysis (TGA). Scanning electron microscopy observations suggested that alkaline treatment resulted in a more damaged RH substrate than bleaching. The dependence of mechanical properties (modulus of rupture, modulus of elasticity, and internal bond) and the physical properties (water absorption and thickness swelling) on chemical treatments performed on both, rice husk and SPC was studied. Bleached-rice husk particleboards bonded with alkaline-treated soybean protein concentrate displayed the best set of final properties. Particleboards with this formulation met the minimum requirements of internal bond, modulus of elasticity and modulus of rupture recommended by the US Standard ANSI/A208.1 specifications for M1, MS and M2-grade medium-density particleboards, but failed to achieve the thickness swelling value recommended for general use panels. This limitation of soybean protein concentrate-bonded rice husk particleboards was counterbalanced by the advantage of being formaldehyde-free which makes them a suitable alternative for indoor applications.

  11. EFFECT OF RICE HUSKS AS FILLER IN POLYMER MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    K. Hardinnawirda

    2012-06-01

    Full Text Available In this study, rice husk-filled polyester composites were produced with rice husks (RH as the filler and unsaturated polyester resin (UPR as the matrix. Several percentages of filler loadings were used (10, 15, 20 and 25 wt % in order to gain insights into the effect of filler content on the mechanical properties and water intake of the composites. The tensile strength of the RH-filled UPR composites was found to decrease as the filler loading increased; however, as it reached 25 wt %, the strength showed a moderate increase. The Young’s modulus showed a remarkable increase for 15 wt % of RH but decreased as the RH percentage increased further to 25 wt %. A water absorption test was conducted and the results showed that the composites absorb more water as the percentage weight of RH increased, which is attributed to the ability of the RH filler to absorb water.

  12. Processing Methods of Alkaline Hydrolysate from Rice Husk

    Directory of Open Access Journals (Sweden)

    Olga D. Arefieva

    2017-07-01

    Full Text Available This paper devoted to finding processing methods of alkaline hydrolysate produced from rice husk pre-extraction, and discusses alkaline hydrolysate processing schemed and disengagement of some products: amorphous silica of various quality, alkaline lignin, and water and alkaline extraction polysaccharides. Silica samples were characterized: crude (air-dried, burnt (no preliminary water treatment, washed in distilled water, and washed in distilled water and burnt. Waste water parameters upon the extraction of solids from alkaline hydrolysate dropped a few dozens or thousand times depending on the applied processing method. Color decreased a few thousand times, turbidity was virtually eliminated, chemical oxygen demanded about 20–136 times; polyphenols content might decrease 50% or be virtually eliminated. The most prospective scheme obtained the two following solid products from rice husk alkaline hydrolysate: amorphous silica and alkaline extraction polysaccharide. Chemical oxygen demand of the remaining waste water decreased about 140 times compared to the silica-free solution.

  13. Effects of pyrolysis temperature on the physicochemical properties of empty fruit bunch and rice husk biochars.

    Science.gov (United States)

    Claoston, N; Samsuri, A W; Ahmad Husni, M H; Mohd Amran, M S

    2014-04-01

    Biochar has received great attention recently due to its potential to improve soil fertility and immobilize contaminants as well as serving as a way of carbon sequestration and therefore a possible carbon sink. In this work, a series of biochars were produced from empty fruit bunch (EFB) and rice husk (RH) by slow pyrolysis at different temperatures (350, 500, and 650°C) and their physicochemical properties were analysed. The results indicate that porosity, ash content, electrical conductivity (EC), and pH value of both EFB and RH biochars were increased with temperature; however, yield, cation exchange capacity (CEC), and H, C, and N content were decreased with increasing pyrolysis temperature. The Fourier transform IR spectra were similar for both RH and EFB biochars but the functional groups were more distinct in the EFB biochar spectra. There were reductions in the amount of functional groups as pyrolysis temperature increased especially for the EFB biochar. However, total acidity of the functional groups increased with pyrolysis temperature for both biochars.

  14. Influence of fly-ash produced by lignite power station on humic substances in ectohumus horizons of Podzols

    Science.gov (United States)

    Weber, Jerzy; Jerzykiewicz, Maria; Jamroz, Elżbieta; Kocowicz, Andrzej; Dębicka, Magdalena; Ćwieląg-Piasecka, Irmina

    2017-04-01

    Literature on fly-ash influence on the environment report mainly on alkalization effect on vegetation and changes in chemistry of forest floor. As far as now soils were examined only for changes in pH in surface horizons, physical properties and heavy metal solubility. Soil properties strongly depend on soil organic matter content and humic substances properties, thus their modification plays a crucial role in soil forming processes and changes in the environment. From the other side, the alkalization effects on podzolization processes and particularly on humic substances have not been recognized. The aim of this paper was to characterize changes in properties of humic substances in ectohumus horizons of Podzols affected by alkali blown out from fly-ash dumping site of power station Bełchatów, central Poland. The objects of the investigation were Podzols derived from loose quartz sand, developed under pine forest. They surround the dumping site, which was established to store wastes from lignite combustion in Bełchatów power station. The samples were collected from ectohumus horizons in direct vicinity of the dumping site (50 m) as well as in the control area (7.3 km away) in five replications. Determination of elemental composition and spectroscopic analysis (EPR, FT-IR, ICP-OES and UV-Vis) were performed for humic acids, fulvic acids and humines extracted with standard IHSS procedure. An increase of pH in ectohumus horizons caused by the influence of fly-ash leads to change in humic substances structure. Obtained results showed that humic and fulvic acids from fly-ash affected Podzols indicated higher contents of nitrogen and sulphur, as well as higher O/C and lower C/N ratios. This points out a higher degree of their humification. Also EPR analyses of humic acids and humins affected by fly-ash indicated higher metal ions concentrations. However, the increase of Mn and Fe ions concentration did not affect the Fe(III) and Mn(II) band intensities of EPR spectra

  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. An investigation into physicochemical characteristics of ash produced from combustion of oil palm biomass wastein a boiler

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Chun Yang; Kadir, Sharifah Aishah Syed Abdul; Lim, Ying Pei; Syed-Ariffin, Sharifah Nawirah; Zamzuri, Zurinawati [Faculty of Chemical Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia)

    2008-07-15

    Ash derived from combustion of Malaysian oil palm biomass (empty fruit bunches consisting of fibers) was physically and chemically characterized in order to provide a comprehensive understanding of its specific properties in terms of toxicity, compositions and reusability. Principal analyses conducted include particle size distribution, scanning electron microscopy, elemental dispersive X-ray, elemental analysis, toxicity characteristic leaching procedure (TCLP) as well as thermogravimetric, X-ray diffractometry and Fourier-transform infrared analyses. TCLP result indicated that the oil palm ash (OPA) should not be classified as toxic wastes in terms of heavy metal leachability since leachable copper, cadmium, lead and nickel concentrations were detected below the stipulated leachability limits. It was determined that the OPA contained high amount of potassium as well as presence of silica which implied its suitability to be reused as crude fertilizer or cement replacement material. (author)

  17. Estimating rates of decompression from textures of erupted ash particles produced by 1999-2006 eruptions of Tungurahua volcano, Ecuador

    Science.gov (United States)

    Wright, Heather M.N.; Cashman, Katharine V.; Mothes, Patricia A.; Hall, Minard L.; Ruiz, Andrés Gorki; Le Pennec, Jean-Luc

    2012-01-01

    Persistent low- to moderate-level eruptive activity of andesitic volcanoes is difficult to monitor because small changes in magma supply rates may cause abrupt transitions in eruptive style. As direct measurement of magma supply is not possible, robust techniques for indirect measurements must be developed. Here we demonstrate that crystal textures of ash particles from 1999 to 2006 Vulcanian and Strombolian eruptions of Tungurahua volcano, Ecuador, provide quantitative information about the dynamics of magma ascent and eruption that is difficult to obtain from other monitoring approaches. We show that the crystallinity of erupted ash particles is controlled by the magma supply rate (MSR); ash erupted during periods of high magma supply is substantially less crystalline than during periods of low magma supply. This correlation is most easily explained by efficient degassing at very low pressures (<<50 MPa) and degassing-driven crystallization controlled by the time available prior to eruption. Our data also suggest that the observed transition from intermittent Vulcanian explosions at low MSR to more continuous periods of Strombolian eruptions and lava fountains at high MSR can be explained by the rise of bubbles through (Strombolian) or trapping of bubbles beneath (Vulcanian) vent-capping, variably viscous (and crystalline) magma.

  18. Cellulose fibers extracted from rice and oat husks and their application in hydrogel.

    Science.gov (United States)

    Oliveira, Jean Paulo de; Bruni, Graziella Pinheiro; Lima, Karina Oliveira; Halal, Shanise Lisie Mello El; Rosa, Gabriela Silveira da; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

    2017-04-15

    The commercial cellulose fibers and cellulose fibers extracted from rice and oat husks were analyzed by chemical composition, morphology, functional groups, crystallinity and thermal properties. The cellulose fibers from rice and oat husks were used to produce hydrogels with poly (vinyl alcohol). The fibers presented different structural, crystallinity, and thermal properties, depending on the cellulose source. The hydrogel from rice cellulose fibers had a network structure with a similar agglomeration sponge, with more homogeneous pores compared to the hydrogel from oat cellulose fibers. The hydrogels prepared from the cellulose extracted from rice and oat husks showed water absorption capacity of 141.6-392.1% and high opacity. The highest water absorption capacity and maximum stress the compression were presented by rice cellulose hydrogel at 25°C. These results show that the use of agro-industrial residues is promising for the biomaterial field, especially in the preparation of hydrogels.

  19. Studies on the properties of rice-husk-filled-PP composites: effect of maleated PP

    Directory of Open Access Journals (Sweden)

    Simone Maria Leal Rosa

    2009-09-01

    Full Text Available Rice husk is a by-product of rice milling process that usually finds inadequate final disposal (burning, land filling. Thermoplastics composites filled with rice husk flour are materials that offer an alternative for using this agricultural resource viewing the production of low dense materials with some specific properties. In this work composites of polypropylene (PP and rice husk flour (RHF were prepared by melt extrusion. Maleic anhydride-modified PP (MAPP was added as a coupling agent. It was verified that tensile strength decreased with filler loading. The presence of MAPP improved this property showing a strong dependence on the MAPP/RHF ratio (MAPP/RHF = 0.03 produced the best results. The density of the composites slightly increased with filler and coupling agent in comparison to pure PP. The presence of MAPP diminished more than 20% water uptake in highly-loaded composites.

  20. Statistical model to predict dry sliding wear behaviour of Aluminium-Jute bast ash particulate composite produced by stir-casting

    Directory of Open Access Journals (Sweden)

    Gambo Anthony VICTOR

    2017-06-01

    Full Text Available A model to predict the dry sliding wear behaviour of Aluminium-Jute bast ash particulate composites produced by double stir-casting method was developed in terms of weight fraction of jute bast ash (JBA. Experiments were designed on the basis of the Design of Experiments (DOE technique. A 2k factorial, where k is the number of variables, with central composite second-order rotatable design was used to improve the reliability of results and to reduce the size of experimentation without loss of accuracy. The factors considered in this study were sliding velocity, sliding distance, normal load and mass fraction of JBA reinforcement in the matrix. The developed regression model was validated by statistical software MINITAB-R14 and statistical tool such as analysis of variance (ANOVA. It was found that the developed regression model could be effectively used to predict the wear rate at 95% confidence level. The wear rate of cast Al-JBAp composite decreased with an increase in the mass fraction of JBA and increased with an increase of the sliding velocity, sliding distance and normal load acting on the composite specimen.

  1. Production process for high density high performance binderless boards from whole coconut husk

    NARCIS (Netherlands)

    Dam, van J.E.G.; Oever, van den M.J.A.; Keijsers, E.R.P.

    2004-01-01

    Coconuts are typically growing in coastal areas of tropical countries. The husk is abundantly available as cheap residue from coconut production in many areas, which is known to yield the coarse coir fibre. In this project a simple and efficient technology has been developed to produce high strength

  2. Production process for high density high performance binderless boards from whole coconut husk

    NARCIS (Netherlands)

    Dam, van J.E.G.; Oever, van den M.J.A.; Keijsers, E.R.P.

    2004-01-01

    Coconuts are typically growing in coastal areas of tropical countries. The husk is abundantly available as cheap residue from coconut production in many areas, which is known to yield the coarse coir fibre. In this project a simple and efficient technology has been developed to produce high strength

  3. Gas chromatographic-mass spectrometric analysis of tar compounds formed during pyrolysis of rice husks

    NARCIS (Netherlands)

    Haanappel, V.A.C.; Stevens, T.W.; Hovestad, A.; Skolnik, V.; Visser, R.

    1991-01-01

    Pyrolysis of agricultural waste to produce fuel gas involves formation of tars as noxious by-products. In this paper the qualitative analysis of tars formed during pyrolysis of rice husks is presented, based on identification by gas chromatography—mass spectrometry and interpolation of retention tim

  4. Chemical Looping Combustion of Rice Husk

    Directory of Open Access Journals (Sweden)

    Rashmeet Singh Monga

    2015-05-01

    Full Text Available 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 pressure and 900˚C was found to be the best operating point for hundred percent carbon conversion in the fuel reactor. Such detailed thermodynamic studies can be useful to design chemical looping combustion processes using different fuels.

  5. UTILIZATION OF RICE HUSK AS RAW MATERIAL IN SYNTHESIS OF MESOPOROUS SILICATES MCM-41

    Directory of Open Access Journals (Sweden)

    Suyanta Suyanta

    2011-12-01

    Full Text Available The research about synthesis and characterization of MCM-41 from rice husk has been done. Silica (SiO2 was extracted from rice husk by refluxing with 3M hydrochloric solution at 80 °C for 3 h. The acid-leached rice husk was filtered, washed, dried and calcined at 650 °C for 6 h lead the rough powder of rice husk silica with light brown in color. Characterization was carried out by X-ray diffraction (XRD and FTIR spectroscopy method. Rice husk silica was dissolved into the sodium hydroxide solution leading to the solution of sodium silicate, and used as silica source for the synthesis of MCM-41. MCM-41 was synthesized by hydrothermal process to the mixture prepared from 29 g of distilled water, 8.67 g of cetyltrimethyl ammonium bromide (CTMAB, 9.31 g of sodium silicate solution, and amount mL of 1 M H2SO4. Hydrothermal process was carried out at 100 °C in a teflon-lined stainless steel autoclave heated in the oven for 36 h. The solid phase was filtered, then washed with deionised water, and dried in the oven at 100 °C for 2 h. The surfactant CTMAB was removed by calcination at 550 °C for 10 h with heating rate 2 °C/min. The as-synthesized and calcined crystals were characterized by using FTIR spectroscopy, X-ray diffraction and N2 physisorption methods. In order to investigate the effect of silica source, the same procedure was carried out by using pure sodium silicate as silica source. It was concluded that silica extracted from rice husk can be used as raw materials in the synthesis of MCM-41, there is no significant difference in crystallinity and pore properties when was compared to material produced from commercial sodium silicate.

  6. Evaluation of Mechanical Properties and Morphological Studies of Rice Husk (Treated/Untreated)-CaCO3 Reinforced Epoxy Hybrid Composites

    Science.gov (United States)

    Verma, Deepak; Joshi, Garvit; Gupta, Ayush

    2016-10-01

    Natural fiber reinforced composites are a very popular area of research because of the easy availability and biodegradability of these fibers. The manufacturing of natural fiber composite is done by reinforcing fibers in the particulate form, fiber form or in woven mat form. Natural fiber composites also utilize industrial wastes as a secondary reinforcements like fly ash, sludge etc. By keeping all these point of views in the present investigation the effect of rice husk flour (chemically treated/untreated) and micro sized calcium carbonate with epoxy resin have been evaluated. The diameter of rice husk flour was maintained at 600 µm through mechanical sieving machine. The husk flour was chemically treated with NaOH (5 % w/v). Mechanical properties like hardness, flexural impact and compression strength were evaluated and found to be superior in modified or chemically treated flour as compared to unmodified or untreated flour reinforced composites. Scanning electron microscopy (SEM) study was also undertaken for the developed composites. SEM study shows the distribution of the rice husk flour and calcium carbonate over the matrix.

  7. Consecutively preparing d-xylose, organosolv lignin, and amorphous ultrafine silica from rice husk.

    Science.gov (United States)

    Zhang, Hongxi; Ding, Xuefeng; Wang, Zichen; Zhao, Xu

    2014-01-01

    Rice husk is an abundant agricultural by-product reaching the output of 80 million tons annually in the world. The most common treatment method of rice husk is burning or burying, which caused serious air pollution and resource waste. In order to solve this problem, a new method is proposed to comprehensively utilize the rice husk in this paper. Firstly, the D-xylose was prepared from the semicellulose via dilute acid hydrolysis. Secondly, the lignin was separated via organic solvent pulping from the residue. Finally, the amorphous ultrafine silica was prepared via pyrolysis of the residue produced in the second process. In this way, the three main contents of rice husk (semicellulose, lignin, and silica) are consecutively converted to three fine chemicals, without solid waste produced. The yields of D-xylose and organosolv lignin reach 58.2% and 58.5%, respectively. The purity and specific surface of amorphous ultrafine silica reach 99.92% and 225.20 m(2)/g.

  8. Consecutively Preparing D-Xylose, Organosolv Lignin, and Amorphous Ultrafine Silica from Rice Husk

    Directory of Open Access Journals (Sweden)

    Hongxi Zhang

    2014-01-01

    Full Text Available Rice husk is an abundant agricultural by-product reaching the output of 80 million tons annually in the world. The most common treatment method of rice husk is burning or burying, which caused serious air pollution and resource waste. In order to solve this problem, a new method is proposed to comprehensively utilize the rice husk in this paper. Firstly, the D-xylose was prepared from the semicellulose via dilute acid hydrolysis. Secondly, the lignin was separated via organic solvent pulping from the residue. Finally, the amorphous ultrafine silica was prepared via pyrolysis of the residue produced in the second process. In this way, the three main contents of rice husk (semicellulose, lignin, and silica are consecutively converted to three fine chemicals, without solid waste produced. The yields of D-xylose and organosolv lignin reach 58.2% and 58.5%, respectively. The purity and specific surface of amorphous ultrafine silica reach 99.92% and 225.20 m2/g.

  9. Ash cloud aviation advisories

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T.J.; Ellis, J.S. [Lawrence Livermore National Lab., CA (United States); Schalk, W.W.; Nasstrom, J.S. [EG and G, Inc., Pleasanton, CA (United States)

    1992-06-25

    During the recent (12--22 June 1991) Mount Pinatubo volcano eruptions, the US Air Force Global Weather Central (AFGWC) requested assistance of the US Department of Energy`s Atmospheric Release Advisory Capability (ARAC) in creating volcanic ash cloud aviation advisories for the region of the Philippine Islands. Through application of its three-dimensional material transport and diffusion models using AFGWC meteorological analysis and forecast wind fields ARAC developed extensive analysis and 12-hourly forecast ash cloud position advisories extending to 48 hours for a period of five days. The advisories consisted of ``relative`` ash cloud concentrations in ten layers (surface-5,000 feet, 5,000--10,000 feet and every 10,000 feet to 90,000 feet). The ash was represented as a log-normal size distribution of 10--200 {mu}m diameter solid particles. Size-dependent ``ashfall`` was simulated over time as the eruption clouds dispersed. Except for an internal experimental attempt to model one of the Mount Redoubt, Alaska, eruptions (12/89), ARAC had no prior experience in modeling volcanic eruption ash hazards. For the cataclysmic eruption of 15--16 June, the complex three-dimensional atmospheric structure of the region produced dramatically divergent ash cloud patterns. The large eruptions (> 7--10 km) produced ash plume clouds with strong westward transport over the South China Sea, Southeast Asia, India and beyond. The low-level eruptions (< 7 km) and quasi-steady-state venting produced a plume which generally dispersed to the north and east throughout the support period. Modeling the sequence of eruptions presented a unique challenge. Although the initial approach proved viable, further refinement is necessary and possible. A distinct need exists to quantify eruptions consistently such that ``relative`` ash concentrations relate to specific aviation hazard categories.

  10. 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)

  11. Property Optimization of Kaolin-Rice Husk Insulating Fire Bricks

    Institute of Scientific and Technical Information of China (English)

    E.O.Onche; B.I.Ugheoke; G.A.Asikpo

    2006-01-01

    In this work, the suitability of using Kaolin-Rice husk-plastic clay to produce insulating firebrick was experimentally investigated and the optimal ratio of these constituents determined. Ten brick samples of different compositions were fired at 1200℃. Three of the samples(samples 6, 7, and 8) crumbled during firing. The surviving samples gave the following limits of results:shrinkage: 9.7% - 13.6%; effective moisture content:28. 34% -32.52%; modulus of rupture: 4.26kgf/cm2 - 19. 10kgf/cm2; apparent porosity: 56%-95. 93%;water absorption: 42.27% - 92. 12%; bulk density:1.04g/cm3 - 1.41g/cm3; apparent density: 2. 56g/cm3 -5. 77g/cm3 ; and thermal conductivity: 0. 005 W/mK 0. 134W/mK. The results showed that they all had good insulating characteristics. Samples 1 -5 and 10 showed good level of refractoriness, while mixing ratio of 4∶1∶2 ( representing weight in grams of Kaolin, plastic clay and rice husk respectively) for sample 4 gave the optimum performance values in terms of refractoriness,thermal conductivity, modulus of rupture, shrinkage and bulk density and the effective moisture content.

  12. One-Pot and Efficient Synthesis of Triazolo[1,2-a]indazole-triones via Reaction of Arylaldehydes with Urazole and Dimedone Catalyzed by Silica Nanoparticles Prepared from Rice Husk

    OpenAIRE

    Asadollah Hassankhani; Sayed Zia Mohammadi; Hooshang Hamidian; Samieh Fozooni

    2011-01-01

    A novel synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives by reaction of urazole, dimedone and aromatic aldehydes under conventional heating and microwave irradiation and solvent-free conditions using silica nanoparticles prepared from rice husk ash as catalyst is described. The new method features high yields, multicomponent reactions and environmental friendliness.

  13. One-Pot and Efficient Synthesis of Triazolo[1,2-a]indazole-triones via Reaction of Arylaldehydes with Urazole and Dimedone Catalyzed by Silica Nanoparticles Prepared from Rice Husk

    Directory of Open Access Journals (Sweden)

    Asadollah Hassankhani

    2011-10-01

    Full Text Available A novel synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives by reaction of urazole, dimedone and aromatic aldehydes under conventional heating and microwave irradiation and solvent-free conditions using silica nanoparticles prepared from rice husk ash as catalyst is described. The new method features high yields, multicomponent reactions and environmental friendliness.

  14. One-pot and efficient synthesis of triazolo[1,2-a]indazole-triones via reaction of arylaldehydes with urazole and dimedone catalyzed by silica nanoparticles prepared from rice husk.

    Science.gov (United States)

    Hamidian, Hooshang; Fozooni, Samieh; Hassankhani, Asadollah; Mohammadi, Sayed Zia

    2011-10-26

    A novel synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives by reaction of urazole, dimedone and aromatic aldehydes under conventional heating and microwave irradiation and solvent-free conditions using silica nanoparticles prepared from rice husk ash as catalyst is described. The new method features high yields, multicomponent reactions and environmental friendliness.

  15. 环氧丙烷装置皂化电石渣处理方案%Feasibility scheme of epoxy propane saponification calcium carbide slag produce autoclaved fly ash brick

    Institute of Scientific and Technical Information of China (English)

    林盛海; 吴学亮

    2012-01-01

    本文介绍了皂化废电石渣用于生产蒸压粉煤灰砖的可行性。%The feasibility scheme of epoxy propane saponification Calcium carbide slag produce autoclaved fly ash brick was introduced.

  16. 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.

  17. Alkali-silica reactions of mortars produced by using waste glass as fine aggregate and admixtures such as fly ash and Li2CO3.

    Science.gov (United States)

    Topçu, Ilker Bekir; Boğa, Ahmet Raif; Bilir, Turhan

    2008-01-01

    Use of waste glass or glass cullet (GC) as concrete aggregate is becoming more widespread each day because of the increase in resource efficiency. Recycling of wastes is very important for sustainable development. When glass is used as aggregate in concrete or mortar, expansions and internal stresses occur due to an alkali-silica reaction (ASR). Furthermore, rapid loss in durability is generally observed due to extreme crack formation and an increase in permeability. It is necessary to use some kind of chemical or mineral admixture to reduce crack formation. In this study, mortar bars are produced by using three different colors of glass in four different quantities as fine aggregate by weight, and the effects of these glass aggregates on ASR are investigated, corresponding to ASTM C 1260. Additionally, in order to reduce the expansions of mortars, 10% and 20% fly ash (FA) as mineral admixture and 1% and 2% Li(2)CO(3) as chemical admixture are incorporated by weight in the cement and their effects on expansion are examined. It is observed that among white (WG), green (GG) and brown glass (BG) aggregates, WG aggregate causes the greatest expansion. In addition, expansion increases with an increase in amount of glass. According to the test results, it is seen that over 20% FA and 2% Li(2)CO(3) replacements are required to produce mortars which have expansion values below the 0.2% critical value when exposed to ASR. However, usages of these admixtures reduce expansions occurring because of ASR.

  18. Ash in the Soil System

    Science.gov (United States)

    Pereira, P.

    2012-04-01

    Ash is the organic and inorganic residue produced by combustion, under laboratory and field conditions. This definition is far away to be accepted. Some researchers consider ash only as the inorganic part, others include also the material not completely combusted as charcoal or biochar. There is a need to have a convergence about this question and define clear "what means ash". After the fire and after spread ash onto soil surface, soil properties can be substantially changed depending on ash properties, that can be different according to the burned residue (e.g wood, coal, solid waste, peppermill, animal residues), material treatment before burning, time of exposition and storage conditions. Ash produced in boilers is different from the produced in fires because of the material diferent propertie and burning conditions. In addition, the ash produced in boilers is frequently treated (e.g pelletization, granulation, self curing) previously to application, to reduce the negative effects on soil (e.g rapid increase of pH, mycorrhiza, fine roots of trees and microfauna). These treatments normally reduce the rate of nutrients dissolution. In fires this does not happen. Thus the implications on soil properties are logically different. Depending on the combustion temperature and/or severity, ash could have different physical (e.g texture, wettability) and chemical properties (e.g amount and type of total and leached nutrients) and this will have implications on soil. Ash can increase and decrease soil aggregation, wettablity and water retention, bulk density, runoff and water infiltration. Normally, ash increases soil pH, Electrical Conductivity, and the amount of some basic nutrients as calcium, magnesium, sodium and potassium. However it is also a potential source of heavy metals, especially if ash pH is low. However the effect of ash on soil in space and time depends especially of the ash amount and characteristics, fire temperature, severity, topography, aspect

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Rajaonarivony Rova Karine

    2017-01-01

    Full Text Available 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.

  1. 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.

  2. 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.

  3. Bioethanol production from coconut husk fiber

    Directory of Open Access Journals (Sweden)

    Mirelle Márcio Santos Cabral

    Full Text Available ABSTRACT: Population growth and the increasing search for healthy foods have led to a major consumption of coconut water and, hence, to an environmental impact caused by the inappropriate disposal of green coconut husks. This lignocellulosic biomass has deserved attention of researchers concerning the seeking of new usages, as, for example, in renewable fuels production technologies. This study examines the potential of green coconut husk fibers as a feedstock for the production of bioethanol. The coconut fibers were pretreated through an alkaline method, hydrolyzed enzymatically and submitted to ethanol fermentation with commercial yeasts of Saccharomyces cerevisiae. Despite the significant loss of cellulose (4.42% in relation to the fiber and 17.9% concerning the original cellulose content, the alkaline pretreatment promoted an efficient solubilization of lignin (80%, turning the coconut fibers into a feasible raw material for 2G ethanol production studies. Enzymatic hydrolysis converted 87% of the sugars and the ethanolic fermentation consumed 81% of the substrate in the hydrolyzate, leading to a sugar to ethanol convertion efficiency of 59.6%. These results points out that green coconut husks are a promising alternative to the production of renewable energy.

  4. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles

    Directory of Open Access Journals (Sweden)

    A. Kylling

    2013-10-01

    Full Text Available The reverse absorption technique is often used to detect volcanic clouds from thermal infrared satellite measurements. From these measurements particle size and mass loading may also be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculate thermal infrared optical properties of highly irregular and porous ash particles and compare these with mass- and volume-equivalent spherical models. Furthermore, brightness temperatures pertinent to satellite observing geometry are calculated for the different ash particle shapes. Non-spherical shapes and volume-equivalent spheres are found to produce a detectable ash signal for larger particle sizes than mass-equivalent spheres. The assumption of mass-equivalent spheres for ash mass loading estimates will underestimate the mass loading by several tens of percent compared to morphologically complex inhomogeneous ash particles.

  5. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles

    Science.gov (United States)

    Kylling, A.; Kahnert, M.; Lindqvist, H.; Nousiainen, T.

    2013-10-01

    The reverse absorption technique is often used to detect volcanic clouds from thermal infrared satellite measurements. From these measurements particle size and mass loading may also be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculate thermal infrared optical properties of highly irregular and porous ash particles and compare these with mass- and volume-equivalent spherical models. Furthermore, brightness temperatures pertinent to satellite observing geometry are calculated for the different ash particle shapes. Non-spherical shapes and volume-equivalent spheres are found to produce a detectable ash signal for larger particle sizes than mass-equivalent spheres. The assumption of mass-equivalent spheres for ash mass loading estimates will underestimate the mass loading by several tens of percent compared to morphologically complex inhomogeneous ash particles.

  6. Enraizamento de manjericão em diferentes substratos e doses de cinzas Stem rooting of basil in different substrates and doses of ash

    Directory of Open Access Journals (Sweden)

    I.M. Silva

    2012-01-01

    of the combinations of the factors substrate (carbonized rice husk and bark brown ground and increase ash (5 mL and 10 mL of rice husk ash 5 mL and 10 mL of husk ash and brown bark no gray with four repetitions. Each experimental unit consisted of 10 cuttings, a total of 400 cuttings. Was evaluated the characteristics percentage of rooting, number and length of roots. There was no significant interaction between the factors evaluated (substrate and ash. Among the characteristics evaluated the carbonized rice showed only differences in root length and root number, while the levels of ash showed only differences in rooting percentage. The study revealed that the dosages of ash had a positive effect on rooting of cuttings of basil, as well as the substrate prepared with rice hulls provided the best conditions for root development. Thus, the rice husk is an alternative, as well as presenting features suitable for rooting also has a low cost of acquisition, being within reach of many producers.

  7. Ash Management Review—Applications of Biomass Bottom Ash

    Directory of Open Access Journals (Sweden)

    Harpuneet S. Ghuman

    2012-10-01

    Full Text Available In industrialized countries, it is expected that the future generation of bioenergy will be from the direct combustion of residues and wastes obtained from biomass. Bioenergy production using woody biomass is a fast developing application since this fuel source is considered to be carbon neutral. The harnessing of bioenergy from these sources produces residue in the form of ash. As the demand for bioenergy production increases, ash and residue volumes will increase. Major challenges will arise relating to the efficient management of these byproducts. The primary concerns for ash are its storage, disposal, use and the presence of unburned carbon. The continual increase in ash volume will result in decreased ash storage facilities (in cases of limited room for landfill expansion, as well as increased handling, transporting and spreading costs. The utilization of ash has been the focus of many studies, hence this review investigates the likely environmental and technological challenges that increased ash generation may cause. The presence of alkali metals, alkaline earth metals, chlorine, sulphur and silicon influences the reactivity and leaching to the inorganic phases which may have significant impacts on soils and the recycling of soil nutrient. Discussed are some of the existing technologies for the processing of ash. Unburned carbon present in ash allows for the exploration of using ash as a fuel. The paper proposes sieve fractionation as a suitable method for the separation of unburnt carbon present in bottom ash obtained from a fixed-bed combustion system, followed by the application of the gasification technology to particle sizes of energy importance. It is hoped that this process will significantly reduce the volume of ash disposed at landfills.

  8. Upgrading the rice husk char obtained by flash pyrolysis for the production of amorphous silica and high quality activated carbon.

    Science.gov (United States)

    Alvarez, Jon; Lopez, Gartzen; Amutio, Maider; Bilbao, Javier; Olazar, Martin

    2014-10-01

    The overall valorization of rice husk char obtained by flash pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous flash pyrolysis in a conical spouted bed reactor at 500°C. Extraction with Na2CO3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800°C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365m(2)g(-1) at the end of 15min.

  9. Probiotic activity of lignocellulosic enzyme as bioactivator for rice husk degradation

    Science.gov (United States)

    Lamid, Mirni; Al-Arif, Anam; Warsito, Sunaryo Hadi

    2017-02-01

    The utilization of lignocellulosic enzyme will increase nutritional value of rice husk. Cellulase consists of C1 (β-1, 4-glucan cellobiohydrolase or exo-β-1,4glucanase), Cc (endo-β-1,4-glucanase) and component and cellobiose (β-glucocidase). Hemicellulase enzyme consists of endo-β-1,4-xilanase, β-xilosidase, α-L arabinofuranosidase, α-D-glukuronidaseand asetil xilan esterase. This research aimed to study the activity of lignocellulosic enzyme, produced by cows in their rumen, which can be used as a bioactivator in rice husk degradation. This research resulted G6 and G7 bacteria, producing xylanase and cellulase with the activity of 0.004 U mL-1 and 0.021 U mL-1; 0.003 ( U mL-1) and 0.026 (U mL-1) respectively.

  10. 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

  11. CHEMICAL AND THERMAL STABILITY OF RICE HUSKS AGAINST ALKALI TREATMENT

    Directory of Open Access Journals (Sweden)

    Bwire S. Ndazi

    2008-11-01

    Full Text Available Chemical and thermal stability of rice husks against alkali treatment with 2 to 8% w/v NaOH are presented and discussed in this paper. The thermal stability of the rice husks was examined by using a thermal gravimetric analysis instrument. Chemical stability was evaluated by examining the organic components of rice husks using proximate analysis. The results indicated that the proportion of lignin and hemicellulose in rice husks treated with NaOH ranging from 4 to 8% decreased significantly by 96% and 74%, respectively. The thermal stability and final degradation temperatures of the alkali-treated rice husks were also lowered by 24-26°C due to degradation of hemicellulose and lignin during alkali treatment. Absence of the onset degradation zones in the alkali-treated rice husks was a further indication that hemicellulose and other volatile substances degraded during alkali treatment. This leads to a conclusion that alkali treatment of rice husks with more than 4% NaOH causes a substantial chemical degradation of rice husks, which subsequently decreases their thermal stability.

  12. Cost-benefit analysis of replacing maize with rice husk ...

    African Journals Online (AJOL)

    Cost-benefit analysis of replacing maize with rice husk supplemented with grindazyme, nutrsea ... Log in or Register to get access to full text downloads. ... Rice husk was added at the expense of maize in the control diet and each experimental ...

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

    Directory of Open Access Journals (Sweden)

    Javed Syed H.

    2015-09-01

    Full Text Available 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. The focus of this research is to conduct TGA of raw and acid treated (20% HCl & 1M H2SO4 SAW at heating rate 10°C/min in the atmosphere of nitrogen. The results were analyzed on the basis of thermograms and it was inferred that 24 hours soaking with 20% HCl prior to thermal degradation enhanced the percent weight loss. The process also improved the percentage of residual weight of SAW indicating the extraction of amorphous silica with increased purity. The effect of acid treatment was verified by determining chemical composition of SAW samples before and after soaking with 20% HCl. Proximate analysis, thermal degradation temperature ranges and percentage of residual weight at 800°C for each of rice husk, wheat husk and bagasse were also quantified to observe the thermal degradation behavior. XRF analysis was performed to observe the effect of acid treatment for extraction of pure silica.

  14. Mechanical properties of rice husk flour reinforced epoxy biocomposite

    Directory of Open Access Journals (Sweden)

    Neeraj Bisht

    2015-06-01

    Full Text Available A bio-composite reinforced with rice husk flour in epoxy resin has been developed. The effect of fibre treatment and weight percentage of rice husk on the mechanical properties was studied and compared with wood dust reinforced epoxy composite. It was observed that addition of rice husk as filler is detrimental to almost all the mechanical properties. About 51% and 26.8% decrease in ultimate strength and Young’s Modulus for 40 wt% untreated rice husk reinforcement was observed. The corresponding decrease in flexural strength and flexural modulus was 51%. Similar trend was also observed in hardness and impact strength. However the mechanical properties of rice husk reinforced biocomposites are found to be superior than wood dust reinforced epoxy composite. SEM microscopy was also done to corroborate the results.

  15. Ash Aggregates in Proximal Settings

    Science.gov (United States)

    Porritt, L. A.; Russell, K.

    2012-12-01

    Ash aggregates are thought to have formed within and been deposited by the eruption column and plume and dilute density currents and their associated ash clouds. Moist, turbulent ash clouds are considered critical to ash aggregate formation by facilitating both collision and adhesion of particles. Consequently, they are most commonly found in distal deposits. Proximal deposits containing ash aggregates are less commonly observed but do occur. Here we describe two occurrences of vent proximal ash aggregate-rich deposits; the first within a kimberlite pipe where coated ash pellets and accretionary lapilli are found within the intra-vent sequence; and the second in a glaciovolcanic setting where cored pellets (armoured lapilli) occur within Diamond Mine, Canada, are the residual deposits within the conduit and vent of the volcano and are characterised by an abundance of ash aggregates. Coated ash pellets are dominant but are followed in abundance by ash pellets, accretionary lapilli and rare cored pellets. The coated ash pellets typically range from 1 - 5 mm in diameter and have core to rim ratios of approximately 10:1. The formation and preservation of these aggregates elucidates the style and nature of the explosive phase of kimberlite eruption at A418 (and other pipes?). First, these pyroclasts dictate the intensity of the kimberlite eruption; it must be energetic enough to cause intense fragmentation of the kimberlite to produce a substantial volume of very fine ash (sustained plume attended by concomitant production of pyroclastic density currents. The size and internal structure of the armoured lapilli provide constraints on the nature of the initial explosive phase of eruption at Kima'Kho. Their proximity to the vent also indicates rapid aggregation within the eruption plume. Within both sequences rapid aggregation of ash particles occurred in proximity to the vent. However, the conditions were substantially different leading to the production of armoured

  16. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  17. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  18. Influence of a modification of the petcoke/coal ratio on the leachability of fly ash and slag produced from a large PCC power plant.

    Science.gov (United States)

    Izquierdo, Maria; Font, Oriol; Moreno, Natalia; Querol, Xavier; Huggins, Frank E; Alvarez, Esther; Diez, Sergi; Otero, Pedro; Ballesteros, Juan Carlos; Gimenez, Antonio

    2007-08-01

    Co-firing of coal with inexpensive secondary fuels such as petroleum coke is expected to increase in the near future in the EU given that it may provide certain economic and environmental benefits with respect to coal combustion. However, changes in the feed fuel composition of power plants may modify the bulk content and the speciation of a number of elements in fly ash and slag. Consequently, leachability of these byproducts also can be modified. This study is focused on identifying the changes in the environmental quality of co-fired fly ash and slag induced by a modification of the petcoke/coal ratio. Petcoke was found to increase the leachable content of V and Mo and to enhance the mobility of S and As. However, with the exception of these elements, the addition of this secondary fuel did not drastically modify the bulk composition or the overall leachability of the resulting fly ash and slag.

  19. 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.

  20. 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.

  1. [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.

  2. Reactive oxygen species produced by NADPH oxidase and mitochondrial dysfunction in lung after an acute exposure to Residual Oil Fly Ashes

    Energy Technology Data Exchange (ETDEWEB)

    Magnani, Natalia D.; Marchini, Timoteo; Vanasco, Virginia [Instituto de Bioquímica Medicina Molecular (IBIMOL-UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires (Argentina); Tasat, Deborah R. [CESyMA, Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, San Martín, Buenos Aires (Argentina); Alvarez, Silvia [Instituto de Bioquímica Medicina Molecular (IBIMOL-UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires (Argentina); Evelson, Pablo, E-mail: pevelson@ffyb.uba.ar [Instituto de Bioquímica Medicina Molecular (IBIMOL-UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires (Argentina)

    2013-07-01

    Reactive O{sub 2} species production triggered by particulate matter (PM) exposure is able to initiate oxidative damage mechanisms, which are postulated as responsible for increased morbidity along with the aggravation of respiratory diseases. The aim of this work was to quantitatively analyse the major sources of reactive O{sub 2} species involved in lung O{sub 2} metabolism after an acute exposure to Residual Oil Fly Ashes (ROFAs). Mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight), and lung samples were analysed 1 h after instillation. Tissue O{sub 2} consumption and NADPH oxidase (Nox) activity were evaluated in tissue homogenates. Mitochondrial respiration, respiratory chain complexes activity, H{sub 2}O{sub 2} and ATP production rates, mitochondrial membrane potential and oxidative damage markers were assessed in isolated mitochondria. ROFA exposure was found to be associated with 61% increased tissue O{sub 2} consumption, a 30% increase in Nox activity, a 33% increased state 3 mitochondrial O{sub 2} consumption and a mitochondrial complex II activity increased by 25%. During mitochondrial active respiration, mitochondrial depolarization and a 53% decreased ATP production rate were observed. Neither changes in H{sub 2}O{sub 2} production rate, nor oxidative damage in isolated mitochondria were observed after the instillation. After an acute ROFA exposure, increased tissue O{sub 2} consumption may account for an augmented Nox activity, causing an increased O{sub 2}{sup ·−} production. The mitochondrial function modifications found may prevent oxidative damage within the organelle. These findings provide new insights to the understanding of the mechanisms involving reactive O{sub 2} species production in the lung triggered by ROFA exposure. - Highlights: • Exposure to ROFA alters the oxidative metabolism in mice lung. • The augmented Nox activity contributes to the high tissue O{sub 2} consumption. • Exposure to ROFA

  3. Production, statistical optimization and application of endoglucanase from Rhizopus stolonifer utilizing coffee husk.

    Science.gov (United States)

    Navya, P N; Pushpa, S Murthy

    2013-08-01

    Coffee cherry husk (CH) is one of the major by-products obtained from coffee processing industry and accounts to 43 ± 5.9% of cellulose. Screening of fungal organism for cellulase production was carried out and the potential organism was identified as Rhizopus stolonifer by internal transcribed spacer's (ITS)-5.8S rDNA analysis. A systematic study with response surface methodology (RSM) based on CCRD was used to study the interactions among the variables such as pH (3-7), moisture (40-80%) and progression duration (72-168 h) of the fermentation process to maximize the enzyme production. Under the optimized cultivation condition, R. stolonifer synthesized 22,109 U/gds. Model validations at optimum operating conditions showed excellent agreement between the experimental results and the predicted responses with a confidence level of 95%. Endoglucanase thus produced was utilized for ethanol production by simultaneous saccharification and fermentation and maximum of 65.5 g/L of ethanol was obtained. This fungal cellulase has also reported to be efficient detergent additives and promising for commercial use. The present study demonstrates coffee husk as a significant bioprocess substrate. Statistical optimization with major parameters for cellulase production can be highly applicable for industrial scale. Furthermore, value addition to coffee husk with sustainable waste management leading to environment conservation can be achieved.

  4. Effect of self-purging pyrolysis on yield of biochar from maize cobs, husks and leaves.

    Science.gov (United States)

    Intani, Kiatkamjon; Latif, Sajid; Kabir, A K M Rafayatul; Müller, Joachim

    2016-10-01

    In this study, biochar was produced from maize residues (cobs, husks, leaves) in a lab-scale pyrolysis reactor without using a purging gas. The physicochemical properties of biomass and biochar were analysed. Box-Behnken design was used to optimise operational conditions for biochar yields. Multivariate correlations of biochar yields were established using reduced quadratic models with R(2)=0.9949, 0.9801 and 0.9876 for cobs, husks and leaves, respectively. Biochar yields were negatively correlated with the temperature, which was significantly influenced by the exothermic reactions during the pyrolysis of maize residues. The heating rate was found to have the least effect on biochar yields. Under optimal conditions, the maximum biochar yields from cobs, husks and leaves were 33.42, 30.69 and 37.91%, respectively. The highest biochar yield from maize leaves was obtained at a temperature of 300°C, a heating rate of 15°C/min and a holding time of 30min.

  5. Kinetics, thermodynamics and mechanistic studies of carbofuran removal using biochars from tea waste and rice husks.

    Science.gov (United States)

    Vithanage, Meththika; Mayakaduwa, S S; Herath, Indika; Ok, Yong Sik; Mohan, Dinesh

    2016-05-01

    This study reports the thermodynamic application and non-linear kinetic models in order to postulate the mechanisms and compare the carbofuran adsorption behavior onto rice husk and tea waste derived biochars. Locally available rice husk and infused tea waste biochars were produced at 700 °C. Biochars were characterized by using proximate, ultimate and surface characterization methods. Batch experiments were conducted at 25, 35, and 45 °C for a series of carbofuran solutions ranging from 5 to 100 mg L(-1) with a biochar dose of 1 g L(-1) at pH 5.0 with acetate buffer. Molar O/C ratios indicated that rice husk biochar (RHBC700) is more hydrophilic than tea waste biochar (TWBC700). Negative ΔG (Gibbs free energy change) values indicated the feasibility of carbofuran adsorption on biochar. Increasing ΔG values with the rise in temperature indicated high favorability at higher temperatures for both RHBC and TWBC. Enthalpy values suggested the involvement of physisorption type interactions. Kinetic data modeling exhibited contribution of both physisorption, via pore diffusion, π*-π electron donor-acceptor interaction, H-bonding, and van der Waals dispersion forces and chemisorption via chemical bonding with phenolic, and amine groups. Equilibrium adsorption capacities of RHBC and TWBC determined by pseudo second order kinetic model were 25.2 and 10.2 mg g(-1), respectively.

  6. 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 differ

  7. Fungus-mediated preferential bioleaching of waste material such as fly - ash as a means of producing extracellular, protein capped, fluorescent and water soluble silica nanoparticles.

    Directory of Open Access Journals (Sweden)

    Shadab Ali Khan

    Full Text Available In this paper, we for the first time show the ability of the mesophilic fungus Fusarium oxysporum in the bioleaching of waste material such as Fly-ash for the extracellular production of highly crystalline and highly stable, protein capped, fluorescent and water soluble silica nanoparticles at ambient conditions. When the fungus Fusarium oxysporum is exposed to Fly-ash, it is capable of selectively leaching out silica nanoparticles of quasi-spherical morphology within 24 h of reaction. These silica nanoparticles have been completely characterized by UV-vis spectroscopy, Photoluminescence (PL, Transmission electron microscopy (TEM, X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR and Energy dispersive analysis of X-rays (EDAX.

  8. 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.

  9. Male-produced pheromone of Spathius agrili, a parasitoid introduced for the biological control of the invasive emerald ash borer, Agrilus planipennis.

    Science.gov (United States)

    Cossé, Allard A; Petroski, Richard J; Zilkowski, Bruce W; Vermillion, Karl; Lelito, Jonathan P; Cooperband, Miriam F; Gould, Juli R

    2012-04-01

    The braconid wasp, Spathius agrili, has been released in the U.S. as a biocontrol agent for the invasive emerald ash borer (Coleoptera: Buprestidae: Agrilus planipennis), a destructive pest of ash trees (Fraxinus spp.). We identified and synthesized seven male-specific volatile compounds. Three of these, dodecanal, (4R,11E)-tetradecen-4-olide, and (Z)-10-heptadecen-2-one, were the key behaviorally active components in flight tunnel bioassays. Male specificity was demonstrated by gas chromatographic comparison of male and female volatile emissions and whole body extracts. Identifications were aided by coupled gas chromatographic-mass spectrometric (GC-MS) analysis, microchemical reactions, NMR, chiral GC analysis, and GC and MS comparison with authentic standards. Both the racemic and chiral forms of the γ-lactone, as well as both E- and Z-isomers were synthesized. Flight tunnel behavioral tests showed positive male and female S. agrili responses to both natural pheromone and synthetic blends, with upwind flight and landing on the source. Large field-cage tests, using yellow sticky traps baited with pheromone, captured approximately 50% of the released male and female wasps in 24-h periods. The use of pheromone-baited traps in the field could simplify the current detection method for determining parasitoid establishment (i.e., laboriously felling and peeling ash trees for recovery of S. agrili from infested EAB larvae).

  10. SUNFLOWER HUSKS AS A SOURCE OF FUNCTIONAL FEED ADDITIVES

    OpenAIRE

    Khusid S. B.; Gneush A. N.; Nesterenko E. E.

    2015-01-01

    The article describes the results of the complex feed additive based on sunflower husk, enriched with beer wort with the addition of pumpkin pulp. We have studied the chemical composition of sunflower husk, which is the secondary resource of the processing plant raw material, selected methods of enrichment of this raw material with the help of fungi Trichoderma harzianum. Cellulolytic enzyme preparations on the basis of fungi of the genus Trichoderma for use in agriculture and animal feed pro...

  11. Value addition of corn husks through enzymatic production of xylooligosaccharides

    Directory of Open Access Journals (Sweden)

    Ashis Kumar Samanta

    Full Text Available ABSTRACT Corn husks are the major wastes of corn industries with meagre economic significance. The present study was planned for value addition of corn husk through extraction of xylan, followed by its enzymatic hydrolysis into xylooligosaccharides, a pentose based prebiotic. Compositional analysis of corn husks revealed neutral detergent fibre 68.87%, acid detergent fibre 31.48%, hemicelluloses 37.39%, cellulose 29.07% and crude protein 2.68%. Irrespective of the extraction conditions, sodium hydroxide was found to be more effective in maximizing the yield of xylan from corn husks than potassium hydroxide (84% vs. 66%. Application of xylanase over the xylan of corn husks resulted into production of xylooligosaccharides with different degree of polymerization namely, xylobiose and xylotriose in addition to xylose monomer. On the basis of response surface model analysis, the maximum yield of xylobiose (1.9 mg/ml was achieved with the enzymatic hydrolysis conditions of pH 5.8, temperature 44°C, enzyme dose 5.7U/ml and hydrolysis time of 17.5h. Therefore, the corn husks could be used as raw material for xylan extraction vis a vis its translation into prebiotic xylooligosaccharides.

  12. The influence of activating agents on the performance of rice husk-based carbon for sodium lauryl sulfate and chrome (Cr) metal adsorptions

    Science.gov (United States)

    Arneli; Safitri, Z. F.; Pangestika, A. W.; Fauziah, F.; Wahyuningrum, V. N.; Astuti, Y.

    2017-02-01

    This research aims to study the influence of activating agents to produce rice husk based-carbon with high adsorption capacity and efficiency for either hazardous organic molecules or heavy metals which are unfriendly for the environment. Firstly, rice husk was burned by pyrolysis at different temperatures to produce rice husk-based carbon. To improve its ability as an adsorbent, carbon was treated with activating agents, namely, H3PO4 and KOH at room and high temperature (420 °C). The performance of carbon was then tested by contacting it with surfactant (SLS). Finally, the surfactant-modified active carbon was applied for chrome metal removal. The result shows that activation of carbon using phosphate acid (H3PO4) was more effective than potassium hydroxide (KOH) conducted at high temperature to adsorb sodium lauryl sulfate (SLS) and chrome metal with the adsorption capacity 1.50 mgg-1 and 0.375 mgg-1, respectively.

  13. 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.

  14. Evaluation of adsorbents for treating stable oil/water/mineral emulsions produced during in-situ bitumen/heavy oil recovery operations. Phase 2. Final report. [Fly ash, red mud and Minuto coal

    Energy Technology Data Exchange (ETDEWEB)

    1985-03-29

    The objective was to make a preliminary assessment of the technical and economic feasibility of treating emulsions from in-situ bitumen/heavy oil recovery operations for recovery of the oil and preparation of suitable water for boiler feed utilizing adsorbents developed within the Separation and Characterization laboratory of Energy Mines and Resources Canada. This project was completed in two phases. In the first phase, a report was prepared which focussed on the characterization of the adsorption behaviour of the novel adsorbents, determination of an appropriate mode of operation and of the approximate cost for producing water for boiler feed. Three adsorbents (fly ash, red mud, Minto coal) were evaluated with respect to their potential for the treatment produced water. Fly ash and Minto coal were determined to have the best potential based on isotherms for total suspended oil (TSO) removal at two pH levels. The most appropriate mode of operation for these two adsorbents was slurry contact followed by precipitation clarification. During the second phase, work was focussed on the development and characterization of the slurry contact and clarification process for the treatment of produced water utilizing the novel adsorbents Minto coal and fly ash and the development of methods that could be used for the recovery of the adsorbed oil and regeneration of the spent adsorbents. The mechanism of oil removal by Minto coal was determined to be emulsion destabilization and precipitation caused by a coagulation type reaction with iron released from the coal, rather than an adsorbtion of oil on organics on the coal surface as originally believed. This study has shown that virgin Minto coal can effectively destabilize wellhead emulsions and that the oil can be separated from the destabilized emulsion by either precipitation or filtration. 3 figs., 15 tabs.

  15. Ash transformation during co-firing coal and straw

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Peter Arendt; Jensen, Anker Degn;

    2007-01-01

    Co-firing straw with coal in pulverized fuel boilers can cause problems related to fly ash utilization, deposit formation, corrosion and SCR catalyst deactivation due to the high contents of Cl and K in the ash. To investigate the interaction between coal and straw ash and the effect of coal...... quality on fly ash and deposit properties, straw was co-fired with three kinds of coal in an entrained flow reactor. The compositions of the produced ashes were compared to the available literature data to find suitable scaling parameters that can be used to predict the composition of ash from straw...... importantly, by reaction with Al and Si in the fly ash. About 70-80% K in the fly ash appears as alumina silicates while the remainder K is mainly present as sulphate. Lignite/straw co-firing produces fly ash with relatively high Cl content. This is probably because of the high content of calcium...

  16. 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.

  17. Development of carbon dioxide adsorbent from rice husk char

    Science.gov (United States)

    Abang, S.; Janaun, J.; Anisuzzaman, S. M.; Ikhwan, F. S.

    2016-06-01

    This study was mainly concerned about the development of carbon dioxide (CO2) adsorbent from rice husk (RH). Several chemical treatments were used to produce activated rice husk char (RHAC) from RH. Initially the RH was refluxed with 3M of sodium hydroxide (NaOH) solution, activation followed by using 0.5M of zinc chloride (ZnCl2) solution and finally acidic treatment by using 0.1M of hydrochloric acid (HCl). Then, the RHAC was functionalized by using 3-chloropropylamine hydrochloride (3-CPA) and noted as RHN. RHN samples were characterized with scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), fourier transform infrared spectroscopy (FTIR). Based on the SEM, the RHN sample had a large pore diameter compared to RH sample after being treated. Based on MIP data, the average pore diameter between RH and RHAC samples were increased significantly from 0.928 microns to 1.017 microns. The RHN sample also had higher total porosity (%) compared to RHAC and RH (58.45%, 47.82% and 45.57% respectively). The total specific surface area of the sample was much increasing from RHO to RHAC (29.17 m2/g and 62.94 m2/g respectively) and slightly being decreasing from RHAC to RHN (58.88 m2/g). FTIR result showed the present of weak band at 1587 cm-1 which demonstrating of the amine group present on the sample. The CO2 capture result showed that the decreasing of operating temperature can increase the breakthrough time of CO2 capture. On the contrary decreasing of CO2 gas flow rate can increase the breakthrough time of CO2 capture. The highest total amount of CO2 adsorbed was 25338.57 mg of CO2/g of RHN sample by using 100 mL/min of gas flow rate at 30oC. Based on adsorption isotherm analysis, the Freundlich isotherm was the best isotherm to describe the CO2 adsorption on the sample.

  18. Microstructure Assessment of Metakaolin Based-Geopolymers Produced with Alternative Silica Sources Exposed to High Temperatures

    Directory of Open Access Journals (Sweden)

    Villaquirán-Caicedo Mónica Alejandra

    2015-01-01

    Full Text Available Ceramic materials more environment friendly and with similar or even better performance than traditional ones can be produced by alkali activation of natural minerals, wastes or industrial by-products. The present study assesses the effect of exposure at 600° and 1200°C of a MK-based geopolymers. Rice husk ash (RHA and silica fume were modified chemically in order to obtain an alternative alkali activator. Exposure to elevated temperatures leads to dehydration of the reaction products and structural reorganization associated with the crystallization of the gel to leucite (KAlSi2O6 and kalsilite (KAlSiO4. The structural changes associated with the thermal treatment also promote a densification and reduction of porosity. The unreacted MK particles embedded into the geopolymeric gel lead to the formation of mullite (2Al2O3 × SiO2 after the thermal treatment at 1200°C.

  19. Obtention of charcoal briquettes from rice husks using low compaction pressure; Obtencao de briquetes de carvao vegetal de cascas de arroz utilizando baixa pressao de compactacao

    Energy Technology Data Exchange (ETDEWEB)

    Morais, Marcia R.; Seye, Omar; Freitas, Katrina T. de; Rodrigues, Monica; Santos, Eyde C.S. dos; Souza, Rubem C.R. [Universidade Federal do Amazonas (CDEAM/UFAM), Manaus, AM (Brazil). Centro de Desenvolvimento Energetico Amazonico

    2006-07-01

    This work consists of the preparation of briquette from carbonized rice's husks in low pressure. The results demonstrate are necessary a fine granulation of the rice's husks coal to obtainment of briquettes. The ultimate analysis of the briquette did not detect the presence of nitrogen and sulfur, and that prevents the formation and emission of acid gases that can produce corrosion in the equipment and pollute the atmosphere. The performance of the briquette production was superior to 80%. The briquettes present high heating value (HHV) 17,73 MJ/kg and adequate mechanic resistance for the use in gasifier-engine system. (author)

  20. Effectivity of locally wood rot fungal isolates in decomposition of leaf and cocoa pod husk waste

    OpenAIRE

    Kuswinanti, Tutik; Rosmana, Ade; Dewi, Vien Sartika; Jamila; Baharuddin

    2014-01-01

    Cocoa pod husk is a major waste of cocoa plants that can be used either as an organic fertilizer or as animal feed. For 972.400 hectares of cocoa plantation, produce as much as 572.900 tons of cocoa beans, while the waste generated reached 1.8766 million tons/year. However, only 94.515 tons of cocoa waste has been utilized. Given the composition of twigs, leaves and cocoa pods that contain lots of lignin and cellulose, further research is needed to find microbes that effective ...

  1. Solidification on fly ash, Yugoslav experiences

    Energy Technology Data Exchange (ETDEWEB)

    Knezevic, D. [Mining Institute, Belgrade (Yugoslavia); Popov, S.; Salatic, D. [Faculty of Mining and Geology, Belgrade (Yugoslavia)

    1997-12-31

    A study was performed on ashes produced in the combustion process of coal from the Kosovo coal basin, in order to determine the potential and conditions of ash self-solidification. Investigations showed that the ash properties allows for the transformation into a solid mass through a controlled mixing with water. The optimal concentration of ash is 50 percent and the hydro-mixture is behaving as a Bingham plastic fluid. Solidification is obtained in a relatively short period (within 3 to 5 days) without additives. The resulting solidified mass is very consistent and stable

  2. Wet physical separation of MSWI bottom ash

    NARCIS (Netherlands)

    Muchova, L.

    2010-01-01

    Bottom ash (BA) from municipal solid waste incineration (MSWI) has high potential for the recovery of valuable secondary materials. For example, the MSWI bottom ash produced by the incinerator at Amsterdam contains materials such as non-ferrous metals (2.3%), ferrous metals (8-13%), gold (0.4 ppm),

  3. Wet physical separation of MSWI bottom ash

    NARCIS (Netherlands)

    Muchova, L.

    2010-01-01

    Bottom ash (BA) from municipal solid waste incineration (MSWI) has high potential for the recovery of valuable secondary materials. For example, the MSWI bottom ash produced by the incinerator at Amsterdam contains materials such as non-ferrous metals (2.3%), ferrous metals (8-13%), gold (0.4 ppm),

  4. Properties and Leachability of Self-Compacting Concrete Incorporated with Fly Ash and Bottom Ash

    Science.gov (United States)

    Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Jamaluddin, Norwati; Bakri Abdullah, Mohd Mustafa Al

    2016-06-01

    The process of combustion in coal-fired power plant generates ashes, namely fly ash and bottom ash. Besides, coal ash produced from coal combustion contains heavy metals within their compositions. These metals are toxic to the environment as well as to human health. Fortunately, treatment methods are available for these ashes, and the use of fly ash and bottom ash in the concrete mix is one of the few. Therefore, an experimental program was carried out to study the properties and determine the leachability of selfcompacting concrete incorporated with fly ash and bottom ash. For experimental study, self-compacting concrete was produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a replacement for sand with the ratios of 10%, 20%, and 30% respectively. The fresh properties tests conducted were slump flow, t500, sieve segregation and J-ring. Meanwhile for the hardened properties, density, compressive strength and water absorption test were performed. The samples were then crushed to be extracted using Toxicity Characteristic Leaching Procedure and heavy metals content within the samples were identified accordingly using Atomic Absorption Spectrometry. The results demonstrated that both fresh and hardened properties were qualified to categorize as self-compacting concrete. Improvements in compressive strength were observed, and densities for all the samples were identified as a normal weight concrete with ranges between 2000 kg/m3 to 2600 kg/m3. Other than that, it was found that incorporation up to 30% of the ashes was safe as the leached heavy metals concentration did not exceed the regulatory levels, except for arsenic. In conclusion, this study will serve as a reference which suggests that fly ash and bottom ash are widely applicable in concrete technology, and its incorporation in self-compacting concrete constitutes a potential means of adding value to appropriate mix and design.

  5. 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.

  6. Pyrolysis of rice husk and sawdust for liquid fuel

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The paper is focused on studying how to convert rice husk and sawdust into liquid fuel. Rice husk, sawdust and their mixture were pyrolyzed at the temperature between 420℃ and 540℃, and the main product of liquid fuel was obtained. The experimental result showed that the yield of liquid fuel heavily depended on the kind of feedstock and pyrolysis temperature. In the experiments, the maximum liquid yields for rice husk, sawdust and their mixture were 56% at 465℃, 61% at 490℃ and 60% at 475℃respectively. Analysis with GC-MS and other apparatus indicated that the liquid fuel is a complicated organic compound with low caloric value and can be directly used as fuel oil without any up-grading. As a crude oil, the liquid fuel can be refined to be vehicle oil.

  7. Volcanic ash infrared signature: porous non-spherical ash particle shapes compared to homogeneous spherical ash particles

    Science.gov (United States)

    Kylling, A.; Kahnert, M.; Lindqvist, H.; Nousiainen, T.

    2014-04-01

    The reverse absorption technique is often used to detect volcanic ash clouds from thermal infrared satellite measurements. From these measurements effective particle radius and mass loading may be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculated thermal infrared optical properties of highly irregular and porous ash particles and compared these with mass- and volume-equivalent spherical models. Furthermore, brightness temperatures pertinent to satellite observing geometry were calculated for the different ash particle shapes. Non-spherical shapes and volume-equivalent spheres were found to produce a detectable ash signal for larger particle sizes than mass-equivalent spheres. The assumption of mass-equivalent spheres for ash mass loading estimates was found to underestimate mass loading compared to morphologically complex inhomogeneous ash particles. The underestimate increases with the mass loading. For an ash cloud recorded during the Eyjafjallajökull 2010 eruption, the mass-equivalent spheres underestimate the total mass of the ash cloud by approximately 30% compared to the morphologically complex inhomogeneous particles.

  8. Preparation and characterization of rice husk/ferrite composites

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A novel ferrite composite using rice husk as substrate has been prepared via high temperature treatment under nitrogen atmosphere.The rice husk substrate consists of porous activated carbon and silica,where spinel ferrite particles with average diameter of 59 nm are distributed.The surface area of the composite is greater than 170 m~2 g~(-1) and the bulk density is less than 0.6 g cm~(-3).Inert atmosphere is indispensable for the synthesis of pure ferrite composites,while different preparation temperatur...

  9. Selective recovery of copper, nickel and zinc from ashes produced from Saccharomyces cerevisiae contaminated biomass used in the treatment of real electroplating effluents.

    Science.gov (United States)

    Machado, Manuela D; Soares, Eduardo V; Soares, Helena M V M

    2010-12-15

    The aim of this work was to seek an environmentally friendly process for recycling metals from biomass-sludges generated in the treatment of industrial wastewaters. This work proposes a hybrid process for selective recovery of copper, nickel and zinc from contaminated biomass of Saccharomyces cerevisiae, used in the bioremediation of electroplating effluents. The developed separation scheme comprised five consecutive steps: (1) incineration of the contaminated biomass; (2) microwave acid (HCl) digestion of the ashes; (3) recovery of copper from the acid solution by electrolysis at controlled potential; (4) recycle of nickel, as nickel hydroxide, by alcalinization of the previous solution at pH 14; (5) recovery of zinc, as zinc hydroxide, by adjusting the pH of the previous solution at 10. This integrated approach allowed recovering each metal with high yielder (>99% for all metals) and purity (99.9%, 92% and 99.4% for copper, nickel and zinc, respectively). The purity of the metals recovered allows selling them in the market or being recycled in the electroplating process without waste generation.

  10. Volcanic ash at Santiaguito dome complex, Guatemala

    Science.gov (United States)

    Hornby, Adrian; Kendrick, Jackie; Lavallée, Yan; Cimarelli, Corrado; von Aulock, Felix; Rhodes, Emma; Kennedy, Ben; Wadsworth, Fabian

    2015-04-01

    Dome-building volcanoes often suffer episodic explosions. Examination of eruptive activity at Santiaguito dome complex (Guatemala) reveals that gas-and-ash explosions are concordant with rapid inflation/ deflation cycles of the active dome. During these explosions strain is accommodated along marginal faults, where tensional fracture mechanisms and friction dominate, complicating the model of ash generation by bubble rupture in magma. Here, we describe textural features, morphology and petrology of ash collected before, during and after a dome collapse event at Santiaguito dome complex on the 28th November 2012. We use QEM-scan (on more than 35000 grains), laser diffraction granulometry and optical and scanning microscopy to characterise the samples. The ash samples show a bimodal size distribution and a range of textures, crystal content and morphologies. The ash particles are angular to sub-angular and are relatively dense, so do not appear to comprise of pore walls. Instead the ash is generally blocky (>70%), similar to the products of shear magma failure. The ash samples show minor variation before, during and after dome collapse, specifically having a smaller grain size and a higher fraction of phenocrysts fragments before collapse. Textural analysis shows vestiges of chemically heterogeneous glass (melt) filaments originating from the crystals and crosscut by fragmentation during volcanic ash formation. High-velocity friction can induce melting of dome lavas, producing similar disequilibrium melting textures. This work shows the importance of deformation mechanisms in ash generation at lava domes and during Vulcanian activity.

  11. Investigation on Leaching Behaviour of Fly Ash and Bottom Ash Replacement in Self-Compacting Concrete

    Science.gov (United States)

    Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

    2016-06-01

    Fly ash and bottom ash are some of the waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. In recent years, many researchers have been interested in studying on the properties of self-compacting concrete incorporated with fly ash and bottom ash but there was very limited research from the combination of fly ash and bottom ash towards the environmental needs. Therefore, this research was focused on investigating the leachability of heavy metals of SCC incorporated with fly ash and bottom ash by using Toxicity Characteristic Leaching Procedure, Synthetic Precipitation Leaching Procedure and Static Leaching Test. The samples obtained from the coal-fired power plant located at Peninsula, Malaysia. In this study, the potential heavy metals leached out from SCC that is produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a substitute for sand with the ratios from 10% to 30% respectively were designated and cast. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results indicated that most of the heavy metals leached below the permissible limits from the United States Environmental Protection Agency and World Health Organization limit for drinking water. As a conclusion, the minimum leaching of the heavy metals from the incorporation of fly ash and bottom ash in self-compacting concrete was found in 20% of fly ash and 20% of bottom ash replacement. The results also indicate that this incorporation could minimize the potential of environmental problems.

  12. Synthesis of nanosized ZSM-5 zeolite using extracted silica from rice husk without adding any alumina source

    Science.gov (United States)

    Sari, Zahra Ghasemi Laleh Vajheh; Younesi, Habibollah; Kazemian, Hossein

    2015-08-01

    The synthesis of analcime and nanosized ZSM-5 zeolites was carried out by a hydrothermal method with silica extracted from rice husk, available as an inexpensive local biowaste, and without the use of an extra alumina source. Amorphous silica (with 88 wt% of SiO2) was extracted from rice husk ash by a suitable alkali solution. The effects of crystallization temperature, time and SiO2/Al2O3 ratio of the initial system on the properties of final products were investigated. For the characterization of the synthesized product, X-ray diffraction, scanning electron microscope, energy dispersive X-ray techniques, Fourier transform infrared and Brunauer-Emmett-Teller method were applied. Crystallinity percentages of analcime and nanosized ZSM-5 were 95.86 and 89.56, respectively, with specific surface area of 353.5 m2 g-1 for ZSM-5. The experimental results revealed that the synthesis of analcime and nanosized ZSM-5 zeolites was more practical with using silica extracted from inexpensive raw materials, while the whole crystallization process was accomplished without adding any alumina source during.

  13. Electricity production potential and social benefits from rice husk, a case study in Pakistan

    Directory of Open Access Journals (Sweden)

    Obaidullah Mohiuddin

    2016-12-01

    Full Text Available Pakistan has been experiencing energy crisis owing to its sole dependence on fossil fuels. Reduction in local fossil fuel reserves has led to an increase in their prices, thereby increasing the cost of electricity. Since the tariff remains the same, Pakistan is over-burdened with circular debts and observes a daily power shortfall of about 12–14 h. Being an Agra-economic country, many major and minor crops are produced and exported in large quantities. This results in a bulk of the agricultural waste which are not utilized. The waste can be utilized to meet the country’s energy demand while mitigating climate change and its impact. The study examines the electricity production potential and social benefits of rice husk in Pakistan. It is estimated in this study that if 70% of rice husk residues are utilized, there will be annual electricity production of 1,328 GWh and the cost of per unit electricity by rice husk is found at 47.36 cents/kWh as compared to 55.22 cents/kWh of electricity generated by coal. Importantly, the study will increase the awareness of the benefits of utilizing agricultural waste for useful products such as silica, with several social and environmental benefits such as a reduction of 36,042 tCO2e/yr of methane, reducing carbon dioxide emissions, improving the air quality, and providing 4.5 k new jobs. The paper concludes with the policy recommendations based on this study.

  14. Rapid toxicity screening of gasification ashes.

    Science.gov (United States)

    Zhen, Xu; Rong, Le; Ng, Wei Cheng; Ong, Cynthia; Baeg, Gyeong Hun; Zhang, Wenlin; Lee, Si Ni; Li, Sam Fong Yau; Dai, Yanjun; Tong, Yen Wah; Neoh, Koon Gee; Wang, Chi-Hwa

    2016-04-01

    The solid residues including bottom ashes and fly ashes produced by waste gasification technology could be reused as secondary raw materials. However, the applications and utilizations of these ashes are very often restricted by their toxicity. Therefore, toxicity screening of ash is the primary condition for reusing the ash. In this manuscript, we establish a standard for rapid screening of gasification ashes on the basis of in vitro and in vivo testing, and henceforth guide the proper disposal of the ashes. We used three different test models comprising human cell lines (liver and lung cells), Drosophila melanogaster and Daphnia magna to examine the toxicity of six different types of ashes. For each ash, different leachate concentrations were used to examine the toxicity, with C0 being the original extracted leachate concentration, while C/C0 being subsequent diluted concentrations. The IC50 for each leachate was also quantified for use as an index to classify toxicity levels. The results demonstrated that the toxicity evaluation of different types of ashes using different models is consistent with each other. As the different models show consistent qualitative results, we chose one or two of the models (liver cells or lung cells models) as the standard for rapid toxicity screening of gasification ashes. We may classify the gasification ashes into three categories according to the IC50, 24h value on liver cells or lung cells models, namely "toxic level I" (IC50, 24h>C/C0=0.5), "toxic level II" (C/C0=0.05gasification plants every day. Subsequently, appropriate disposal methods can be recommended for each toxicity category. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. 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

  16. Volcanic ash impacts on critical infrastructure

    Science.gov (United States)

    Wilson, Thomas M.; Stewart, Carol; Sword-Daniels, Victoria; Leonard, Graham S.; Johnston, David M.; Cole, Jim W.; Wardman, Johnny; Wilson, Grant; Barnard, Scott T.

    2012-01-01

    Volcanic eruptions can produce a wide range of hazards. Although phenomena such as pyroclastic flows and surges, sector collapses, lahars and ballistic blocks are the most destructive and dangerous, volcanic ash is by far the most widely distributed eruption product. Although ash falls rarely endanger human life directly, threats to public health and disruption to critical infrastructure services, aviation and primary production can lead to significant societal impacts. Even relatively small eruptions can cause widespread disruption, damage and economic loss. Volcanic eruptions are, in general, infrequent and somewhat exotic occurrences, and consequently in many parts of the world, the management of critical infrastructure during volcanic crises can be improved with greater knowledge of the likely impacts. This article presents an overview of volcanic ash impacts on critical infrastructure, other than aviation and fuel supply, illustrated by findings from impact assessment reconnaissance trips carried out to a wide range of locations worldwide by our international research group and local collaborators. ‘Critical infrastructure’ includes those assets, frequently taken for granted, which are essential for the functioning of a society and economy. Electricity networks are very vulnerable to disruption from volcanic ash falls. This is particularly the case when fine ash is erupted because it has a greater tendency to adhere to line and substation insulators, where it can cause flashover (unintended electrical discharge) which can in turn cause widespread and disruptive outages. Weather conditions are a major determinant of flashover risk. Dry ash is not conductive, and heavy rain will wash ash from insulators, but light rain/mist will mobilise readily-soluble salts on the surface of the ash grains and lower the ash layer’s resistivity. Wet ash is also heavier than dry ash, increasing the risk of line breakage or tower/pole collapse. Particular issues for water

  17. Obtenção de mulita porosa a partir da sílica da casca de arroz e do acetato de alumínio Porous mullite obtained using silica from rice husk and aluminum acetate

    Directory of Open Access Journals (Sweden)

    R. R. Menezes

    2008-06-01

    Full Text Available O grande volume de produção de arroz no mundo gera uma enorme quantidade de rejeito na forma de cascas e de cinzas oriundas da queima da casca. Esses resíduos são fontes de poluição e contaminação, podendo agredir diretamente a saúde da população. Assim, esse trabalho tem por objetivo a obtenção de mulita porosa a partir da sílica da casca de arroz e do acetato de alumínio. O resíduo foi física e quimicamente caracterizado e em seguida misturado com acetato de alumínio para a produção do precursor da mulita. O material precursor foi caracterizado termicamente e com base nos resultados foi calcinado a 850 ºC e 1200 ºC. Os corpos de prova foram queimados a 1500 ºC e 1600 ºC e caracterizados pela determinação de sua porosidade aparente, absorção de água e densidade aparente e por difração de raios X e microscopia eletrônica de varredura. Os resultados indicaram que a sílica é constituída por material amorfo e aglomerados micrométricos de partículas submicrométricas e nanométricas. Com base nos resultados conclui-se que a sílica obtida da casca de arroz e o acetato de alumínio podem ser utilizados com sucesso para a produção de corpos mulíticos porosos com porosidades superiores a 48%.The production of rice around the world generates large amounts of waste in the form of husks and ashes from husks burning, which are sources of environmental contamination and pollution. The aim of this work was obtain porous mullite bodies using the silica from the rice husk and aluminum acetate. The waste material was physically and chemically characterized. The mullite precursor was produced mixing the waste and aluminum acetate. The thermal behavior of mullite precursor was described. The precursor was fired at 850 ºC and 1200 ºC and sample bodies were sintered at 1500 and 1600 ºC. Sintered samples were characterized to determine their apparent porosity, water absorption, apparent density, and microstructurally

  18. Selective catalytic reduction of NO by ammonia over oil shale ash and fly ash catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Changtao Yue; Shuyuan Li [University of Petroleum, Beijing (China). State Key Lab of Heavy Oil Processing

    2003-07-01

    Acid rain and urban air pollution, produced mainly by pollutants such as SOX and NOX and other volatile organic compounds, has become the most serious environmental problem. The selective catalytic reduction (SCR) of NO with NH{sub 3} in the presence of oxygen is a wellproven method to limit the NOX emissions. The work in this field has been the subject of much research in recent years. In this paper, NO reduction with NH{sub 3} over oil shale ash or fly ash catalysts was studied. Fe, Cu, V or Ni as active elements was loaded by adding aqueous solutions of the metal nitrate over the oil shale ash or fly ash support. The activities of the catalysts for NO removal were measured in a fixed-bed reactor. According to the results, oil shale ash or fly ash, after pre-treatment, can be reasonably used as the SCR catalyst support to remove NO from flue gas. Cu gave the highest catalytic activity and NO conversion for fly ash while V for oil shale ash. As the support, fly ash is more feasible than oil shale ash. Because of their low cost and high efficiency, the catalysts should be used in the SCR process. Further research on this subject is necessary in the future to understand more details of the SCR system and issue of pollution control. 9 refs., 2 figs., 2 tabs.

  19. Enzymatic hydrolysis of cocoa pod husks. [Trichoderma reesei

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, B.K.; Oldham, J.H.; Martin, A.M

    1984-07-01

    Laboratory results are presented of the bioconversion of cellulose from cocoa pod husks, utilizing cellulase from three mutants of Trichoderma reesei. Total reducing sugars in filtered hydrolysates were estimated by the dinitrosalicylic acid method. The sugars present were identified by paper chromatography as glucose and xylose.

  20. 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.

  1. Adiabatic Gasification and Pyrolysis of Coffee Husk Using Air-Steam for Partial Oxidation

    Directory of Open Access Journals (Sweden)

    Catalina Rodriguez

    2011-01-01

    Full Text Available Colombian coffee industry produces about 0.6 million tons of husk (CH per year which could serve as feedstock for thermal gasification to produce gaseous and liquid fuels. The current paper deals with: (i CH adiabatic gasification modeling using air-steam blends for partial oxidation and (ii experimental thermogravimetric analysis to determine the CH activation energy (E. The Chemical Equilibrium with Applications Program (CEA, developed by NASA, was used to estimate the effect of equivalence ratio (ER and steam to fuel ratio (S : F on equilibrium temperature and gas composition of ~150 species. Also, an atom balance model was developed for comparison purposes. The results showed that increased ER and (S : F ratios produce mixtures that are rich in H2 and CO2 but poor in CO. The value for the activation energy was estimated to be 221 kJ/kmol.

  2. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk

    Directory of Open Access Journals (Sweden)

    Rudy Agustriyanto

    2012-12-01

    Full Text Available Coconut husk is classified as complex lignocellulosic material that contains cellulose, hemicellulose, lignin, and some other extractive compounds. Cellulose from coconut husk can be used as fermentation substrate after enzymatic hydrolysis. In contrary, lignin content from the coconut husk will act as an inhibitor in this hydrolysis process. Therefore, a pretreatment process is needed to enhance the hydrolysis of cellulose. The objective of this research is to investigate the production of the glucose through dilute acid pretreatment and to obtain its optimum operating conditions. In this study, the pretreatment was done using dilute sulfuric acid in an autoclave reactor. The pretreatment condition were varied at 80°C, 100°C, 120°C and 0.9%, 1.2%, 1.5% for temperature and acid concentration respectively. The acid pretreated coconut husk was then hydrolyzed using commercial cellulase (celluclast and β-glucosidase (Novozyme 188. The hydrolysis time was 72 hours and the operating conditions were varied at several temperature and pH. From the experimental results it can be concluded that the delignification temperature variation has greater influence than the acid concentration. The optimum operating condition was obtained at pH 4 and 50°C which was pretreated at 100°C using 1.5% acid concentration. Copyright © 2012 by BCREC UNDIP. All rights reserved. (Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 28th September 2012, Revised: 2nd October 2012, Accepted: 4th October 2012[How to Cite: R. Agustriyanto, A. Fatmawati, Y. Liasari. (2012. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2: 137-141. doi:10.9767/bcrec.7.2.4046.137-141] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.4046.137-141 ] | View in 

  3. 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.

  4. Effect of fuel properties on the bottom ash generation rate by a laboratory fluidized bed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Rozelle, P.L.; Pisupati, S.V.; Scaroni, A.W. [Penn State University, University Park, PA (United States). Dept. of Energy & Geoenvironmental Engineering

    2007-06-15

    The range of fuels that can be accommodated by an FBC boiler system is affected by the ability of the fuel, sorbent, and ash-handling equipment to move the required solids through the boiler. Of specific interest is the bottom ash handling equipment, which must have sufficient capacity to remove ash from the system in order to maintain a constant bed inventory level, and must have sufficient capability to cool the ash well below the bed temperature. Quantification of a fuel's bottom ash removal requirements can be useful for plant design. The effect of fuel properties on the rate of bottom ash production in a laboratory FBC test system was examined. The work used coal products ranging in ash content from 20 to 40+ wt. %. The system's classification of solids by particle size into flyash and bottom ash was characterized using a partition curve. Fuel fractions in the size range characteristic of bottom ash were further analyzed for distributions of ash content with respect to specific gravity, using float sink tests. The fuel fractions were then ashed in a fixed bed. In each case, the highest ash content fraction produced ash with the coarsest size consist (characteristic of bottom ash). The lower ash content fractions were found to produce ash in the size range characteristic of flyash, suggesting that the high ash content fractions were largely responsible for the production of bottom ash. The contributions of the specific gravity fractions to the composite ash in the fuels were quantified. The fuels were fired in the laboratory test system. Fuels with higher amounts of high specific gravity particles, in the size ranges characteristic of bottom ash, were found to produce more bottom ash, indicating the potential utility of float sink methods in the prediction of bottom ash removal requirements.

  5. Construction procedures using self hardening fly ash

    Science.gov (United States)

    Thornton, S. I.; Parker, D. G.

    1980-07-01

    Fly ash produced in Arkansas from burning Wyoming low sulfur coal is self-hardening and can be effective as a soil stabilizing agent for clays and sands. The strength of soil-self hardening fly ash develops rapidly when compacted immediately after mixing. Seven day unconfined compressive strengths up to 1800 psi were obtained from 20% fly ash and 80% sand mixtures. A time delay between mixing the fly ash with the soil and compaction of the mixture reduced the strength. With two hours delay, over a third of the strength was lost and with four hours delay, the loss was over half. Gypsum and some commercial concrete retarders were effective in reducing the detrimental effect of delayed compaction. Adequate mixing of the soil and fly ash and rapid compaction of the mixtures were found to be important parameters in field construction of stabilized bases.

  6. Effect of biomass on temperatures of sintering and initial deformation of lignite ash

    Energy Technology Data Exchange (ETDEWEB)

    H. Haykiri-Acma; S. Yama; S. Kucukbayrak [Istanbul Technical University, Istanbul (Turkey). Faculty of Chemical and Metallurgical Engineering

    2010-10-15

    Sintering temperatures and the initial deformation temperatures of ashes from Turkish Elbistan lignite, and biomass species such as hazelnut shell and rice husk were investigated up to 1450{sup o}C by Heating Microscope Technique. Sintering temperatures were found 1300, 1269, and 1320{sup o}C for hazelnut shell, rice husk, and lignite, respectively, while the initial deformation temperatures were >1450, 1370, and >1450{sup o}C. Lignite/biomass blends were prepared by adding of biomass into coal in the ratios of 5 or 10 wt.%, and then effects of biomass presence on sintering temperature and the initial deformation temperature were tested. It was determined that the addition of potassium-rich hazelnut shell reduced the sintering temperatures to 919 and 730{sup o}C for the blends of 5 and 10 wt.%, respectively. Also, initial deformation temperature dropped to 788{sup o}C in case of the blend of 10 wt.%. Such a big antagonistic influence of hazelnut shell on the thermal behaviour of ash is attributed to the interaction of potassium from biomass with silicon compounds found in mineral matter of lignite. In addition, concentration of CaO may be another reason for this. On the other hand, the presence of rice husk showed limited effect on the sintering temperature as well the initial deformation temperature. 20 refs., 3 figs., 5 tabs.

  7. [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...

  8. Synthesis and Thermomechanical Properties of Polyurethanes and Biocomposites Derived from Macauba Oil and Coconut Husk Fibers

    Directory of Open Access Journals (Sweden)

    Rafael L. Quirino

    2015-08-01

    Full Text Available This work reports on a very effective route to produce bio-based polyurethanes (PUs and composites with high content of renewable carbon sources. The PUs are prepared with polyols synthesized from macauba oil (Acrocomia aculeata and methylene diphenyl diisocyanate, at different [NCO]/[OH] molar ratios. Later, biocomposites are prepared with the as-obtained PUs reinforced with coconut husk fibers. The successful synthesis of natural oil-based polyols is ascribed to the hydroxylation and consumption of carbon-carbon double bonds in the fatty acid chains of the original starting oil as attested by FTIR spectroscopy. According to different thermal analysis techniques (TG, DTG, and DTA, the increase in the [NCO]/[OH] molar ratio improves the thermal stability of PUs, likely due to an increase of crosslinks. Dynamic mechanical analysis evidences the reinforcement effect of coconut husk fibers in bio-based PUs. The present PUs and composites are of low-cost and environmentally friendly materials for structural applications.

  9. Improving Impact Strength Recovery of Fractured and Healed Rice Husks Fibre Reinforced Polypropylene Composites.

    Directory of Open Access Journals (Sweden)

    Odhong, O.V.E

    2016-10-01

    Full Text Available Rice husks fibre reinforced polypropylene composite (rhfrpc is a natural plant fibre reinforced polymer composite having advantages of high strength, light weight and affordability. They are commonly used for light load structural and non structural applications. They are mainly used as particle boards, for fencing post, roofing tiles, for interiors of car and aircrafts among other usages. This material once cracked by impact forces cannot be repaired using traditional repair methods for engineering materials such as metals or other composites that can be repaired by welding or by patch repair methods respectively, thus a method of repair of rice husks fibre reinforced polypropylene composites by refilling the damaged volume by injection of various healing agents has been investigated. The composite coupons were produced by injection moulding, cooled sufficiently and prepared for charpy impact tests. Test results for pristine coupons were a maximum of 48 J/mm2 . The destroyed coupons were then subjected to healing in a fabricated healing fixture. Healing agents such as epoxy resin, ethyl cyanoacrylate, and tannin gum have been investigated for their use as possible healing agents to fill the damaged volume and perform healing action at the fractured surfaces. The impact test results were recorded and compared with those of unhealed pristine coupons. The recovered strengths were a maximum of 60 J/mm2 translating into a 125% impact strength recovery, and this is good enough for the healed composites to be recommended for reuse in their second lives of their respective original functions.

  10. Effects of water washing and torrefaction pretreatments on rice husk pyrolysis by microwave heating.

    Science.gov (United States)

    Zhang, Shuping; Dong, Qing; Zhang, Li; Xiong, Yuanquan; Liu, Xinzhi; Zhu, Shuguang

    2015-10-01

    The influences of water washing, torrefaction and combined water washing-torrefaction pretreatments on microwave pyrolysis of rice husk samples were investigated. The results indicated that the process of combined water washing-torrefaction pretreatment could effectively remove a large portion of inorganics and improve the fuel characteristics to a certain extent. The gas products were rich in combustible compositions and the syngas quality was improved by pretreatment process. The liquid products contained less moisture content, acids and furans, while more concentrated phenols and sugars from microwave pyrolysis of rice husk after pretreatments, especially after the combined water washing-torrefaction pretreatment. Biochar, produced in high yield, has the alkaline pH (pH 8.2-10.0) and high surface area (S(BET) 157.81-267.84 m(2)/g), they have the potential to be used as soil amendments. It is noteworthy that water washing increased the pore surface area of biochar, but torrefaction reduced the pore surface area.

  11. PROXIMATE ANALYSIS AND ANTI-NUTRITIONAL FACTORS OF GROUNDNUT AND MELON HUSK

    Directory of Open Access Journals (Sweden)

    S. ABDULRAZAK

    2014-03-01

    Full Text Available Groundnut and Melon husks (shell were collected from the market side in Kaduna metropolis, Kaduna State and milled into powder for proximate and anti-nutritional analysis. The results of proximate analysis showed that groundnut shell contained moisture content, ash content, crude fibre, lipid, crude protein, carbohydrate, oxalate, phytate, cyanogenic glycosides and trypsin inhibitor are 8.0%, 2.50%, 59.0%, 0.50%, 4.43%, 25.57%, 220mg/100g, 362.1mg/100g, 1.60mg/100g, and 25 TUI/mg respectively while melon shells contained 7.50%, 6.50%, 51.50%, 11.90%, 4.68%, 17.92%,132mg/100g, 62mg/100g,0.50 and 60 TUI/mg. These two agricultural wastes were found to have high nutritive values and low anti-nutritive values and can be used as an alternative source of animal feeds for herbivores and also solve a waste disposal problem and helping in turning waste into a wealth.

  12. 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.

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

    African Journals Online (AJOL)

    HOD

    INTRODUCTION. Silica sand is a good foundry material for casting of both ... Nigerian Journal of Technology (NIJOTECH). Vol. 36, No. ... 3, July 2017 795 cast without the ... also constitutes environmental health hazard. The thermal ... 10 12. Table 5: Sand Specimen with wt. % of RHA. S/No. 1. 2. 3. 4. 5. 6. 7. Specimen RH ...

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

    African Journals Online (AJOL)

    eobe

    2016-01-01

    Jan 1, 2016 ... The values were 190 minutes and 205minutes respectively at 5% ... Fonio is the name given to cultivated grains in the. Digitaria genius. ... its uses and ease of cultivation. ... compared to the control for both water cured and.

  15. 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.

  16. Oil ash corrosion; A review of utility boiler experience

    Energy Technology Data Exchange (ETDEWEB)

    Paul, L.D. (Babcock and Wilcox Co., Alliance, OH (United States)); Seeley, R.R. (Babcock and Wilcox Canada Ltd., Cambridge, ON (Canada))

    1991-02-01

    In this paper a review of experience with oil ash corrosion is presented along with current design practices used to avoid excessive tube wastage. Factors influencing oil ash corrosion include fuel chemistry, boiler operation, and boiler design. These factors are interdependent and determine the corrosion behavior in utility boilers. Oil ash corrosion occurs when vanadium-containing ash deposits on boiler tube surfaces become molten. These molten ash deposits dissolve protective oxides and scales causing accelerated tube wastage. Vanadium is the major fuel constituent responsible for oil ash corrosion. Vanadium reacts with sodium, sulfur, and chlorine during combustion to produce lower melting temperature ash compositions, which accelerate tube wastage. Limiting tube metal temperatures will prevent ash deposits from becoming molten, thereby avoiding the onset of oil ash corrosion. Tube metal temperatures are limited by the use of a parallel stream flow and by limiting steam outlet temperatures. Operating a boiler with low excess air has helped avoid oil ash corrosion by altering the corrosive combustion products. Air mixing and distribution are essential to the success of this palliative action. High chromium alloys and coatings form more stable protective scaled on tubing surfaces, which result in lower oil ash corrosion rates. However, there is not material totally resistant to oil ash corrosion.

  17. Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling

    Science.gov (United States)

    Park, D.; Woo, N. C.; Kim, H.; Yoon, H.; Chung, D.

    2011-12-01

    By 2009, coal ashes produced from coal-based power plants in Korea have been reused as cement supplement materials; however, the rest is mostly disposed in landfills inside the plant properties. Continuous production of coal ashes and limited landfill sites require more recycles of coal ashes as base materials, specifically in constructions of roads and of huge industrial complex. Previous researches showed that coal ashes could contain various metals such as arsenic(As), chromium(Cr), lead(Pb), nickel(Ni), selenium(Se), etc. In this study, we collected four types of bottom ashes and two of fly ashes from four coal-based power plants. These ash samples were tested with distilled water through the column leaching process in oxidized conditions. The column test results were compared with those of total digestion, sequential extraction processes and TCLP. Concentrations of metals in outflows from columns are generally greater in fly ashes than in bottom ashes, specifically for As, Se, B, Sr and SO4. Only one fly ash (J2-F) shows high concentrations of arsenic and selenium in leachate. Sequential extraction results indicate that these metals are in readily soluble forms, such as adsorbed, carbonated, and reducible forms. Results of TCLP analysis indicate no potential contaminants leached from the ashes. In conclusion, recycling of coal combustion ashes could be encouraged with proper tests such as sequential and leaching experiments.

  18. Removal of fly-ash and dust particulate matters from syngas produced by gasification of coal by using a multi-stage dual-flow sieve plate wet scrubber.

    Science.gov (United States)

    Kurella, Swamy; Meikap, Bhim Charan

    2016-08-23

    In this work, fly-ash water scrubbing experiments were conducted in a three-stage lab-scale dual-flow sieve plate scrubber to observe the performance of scrubber in fly-ash removal at different operating conditions by varying the liquid rate, gas rate and inlet fly-ash loading. The percentage of fly-ash removal efficiency increases with increase in inlet fly-ash loading, gas flow rate and liquid flow rate, and height of the scrubber; 98.55% maximum percentage of fly-ash removal efficiency (ηFA) is achieved at 19.36 × 10(-4) Nm(3)/s gas flow rate (QG) and 48.183 × 10(-6) m(3)/s liquid flow rate (QL) at 25 × 10(-3) kg/Nm(3) inlet fly-ash loading (CFA,i). A model has also been developed for the prediction of fly-ash removal efficiency of the column using the experimental results. The predicted values calculated using the correlation matched well with the experimental results. Deviations observed between the experimental and the predicted values were less than 20%.

  19. Alkali-activation potential of biomass-coal co-fired fly ash

    OpenAIRE

    Shearer, C.R.; Provis, J.L.; Bernal, S.A.; Kurtis, K.E.

    2016-01-01

    Co-fired fly ash, derived from the co-combustion of coal and biomass, is examined as a potential precursor for geopolymers. Compared to a coal fly ash, two co-fired fly ashes have a lower vitreous content and higher carbon content, primarily due to differing combustion processing variables. As a result, binders produced with these co-fired fly ashes have reduced reaction potential. Nevertheless, compressive strengths are generally highest for all ashes activated with solutions with a molar ra...

  20. A Review: The Effect of Grinded Coal Bottom Ash on Concrete

    Directory of Open Access Journals (Sweden)

    Basirun Nurul Fasihah

    2017-01-01

    Full Text Available This paper offers a review on the use of grinded coal bottom ash (CBA on the concrete properties as demonstrated by strength test and microstructure test. Amount of CBA from power plant station was disposed in landfill because of the particle shape had a rough particles. By finding an alternative way to gain its surface area by grinding and used as replacement material as cement replacement may give a good side feedback on the strength and morphology of concrete. Most of the prior works studied on the grinded fly ash and grinded rice husk ash. The study on the influence of grinded CBA on the properties of concrete still limited and need more attention Therefore, the review on the effect of grinded CBA on the strength and microstructure of concrete are discussed.

  1. Cementing Properties of Oil Shale Ash

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The oil crisis has prompted renewed interest in direct burning of oil shale as an alternative energy source.A major problem in this process is the large portion of ash produced.The cementing properties of this ash were investigated to determine its applicability as a building material.By means of XRD, IR, NMR and ICP, we have studied the effects of burning temperature on the reactivity of ash.Maximum reactivity was obtained with ash samples produced at 700 °C to 900 °C.In this range, the strength of oil-shale-based material, with properties similar to cement, which is composed of oil shale and several other kinds of solid wastes, can achieve the standard of 42.5# cement.Our study has provided an experimental foundation and theoretical base for a massive utilization of oil shale.

  2. The Produce of Methyl Ester from Crude Palm Oil (CPO) Using Heterogene Catalyst Ash of Chicken Bone (CaO) using Ethanol as Solvent

    Science.gov (United States)

    Sinaga, M. S.; Fauzi, R.; Turnip, J. R.

    2017-03-01

    Methyl Ester (methyl ester) is generally made by trans esterification using heterogeneous base catalyst. To simplify the separation, the heterogeneous catalyst is used, such as CaO, which in this case was isolated from chicken bones made by softening chicken bones and do calcination process. Some other important variables other than the selection of the catalyst is the catalyst dosage, molar ratio of ethanol to the CPO and the reaction temperature. The best result from this observe is at the molar ratio of ethanol to the CPO is 17: 1, the reaction temperature is 70 ° C and 7% catalyst (w.t) with reaction time for 7 hours at 500 rpm as a constant variable, got 90,052 % purity, so that this result does not get the standard requirements of biodiesel, because of the purity of the biodiesel standard temporary must be achieve > 96.5 %. This study aims to produce methyl ester yield with the influence of the reaction temperature, percent of catalyst and molar ratio of ethanol and CPO. The most influential variable is the temperature of the reaction that gives a significant yield difference of methyl ester produced. It’s been proven by the increasing temperature used will also significantly increase the yield of methyl ester.

  3. An integrated process to produce bio-ethanol and xylooligosaccharides rich in xylobiose and xylotriose from high ash content waste wheat straw.

    Science.gov (United States)

    Huang, Chen; Lai, Chenhuan; Wu, Xinxing; Huang, Yang; He, Juan; Huang, Caoxing; Li, Xin; Yong, Qiang

    2017-10-01

    A bio-refinery process of wheat straw pulping solid residue (waste wheat straw, WWS) was established by combining prewashing and liquid hot water pretreatment (LHWP). The results showed that employing a prewashing step prior to the LHWP remarkably improved enzymatic glucose yields from 39.7% to 76.6%. Moreover, after 96h simultaneous saccharification and fermentation (SSF), identical ethanol yields of 0.41g/g-cellulose were obtained despite varied solid loadings (5-30%). Beyond ethanol, enzymatic post-hydrolysis of the prehydrolyzate effectively increased xylobiose and xylotriose yields from 15mg/g-WWS and 14mg/g-WWS to 53mg/g-WWS and 20mg/g-WWS, respectively. For mass balance, about 10.9tons raw WWS will be consumed to produce 1ton ethanol, in addition to producing 614.8kg xylooligosaccharides (XOS) containing 334.3kg xylobiose and 124.8kg xylotriose. The results demonstrated that the integrated process for the WWS bio-refinery is promising, based on value-adding co-production in addition to robust ethanol yields. Copyright © 2017. Published by Elsevier Ltd.

  4. 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. 

  5. NANOCELLULOSE FROM RICE HUSK FOLLOWING ALKALINE TREATMENT TO REMOVE SILICA

    Directory of Open Access Journals (Sweden)

    Leandro Ludueña

    2011-03-01

    Full Text Available The present work deals with the use of multiple-step procedures to obtain valuable sub-products, including nanocellulose, from rice husk. Each sub-product was characterized after every step by analyzing the chemical composition (mainly based on thermogravimetric analysis, Fourier transformed infrared spectra, and X-ray diffraction and morphology (using visual observations and scanning electron microscopy. The results clearly showed that the selected procedure gave the possibility to separate silica in the first step and then to purify the resultant material, leading to nanocellulose production. All acquired sub-products can be used as additives and fillers in a very wide range of applications. The obtained results will be useful both from technological and academic points of view, mainly for people working in the field of biocomposites. The final material could give added value to a raw biomass material source such as rice husk.

  6. Making sense of HUSK: practice implications for social change initiatives.

    Science.gov (United States)

    McBeath, Bowen

    2015-01-01

    As an exemplar of bottom-up progressive social experimentation, HUSK provides opportunities to examine how innovative practice is supported and challenged in bureaucratic settings. In this analysis the author uses a sensemaking lens to identify critical issues and questions for those seeking to promote progressive change initiative in social welfare systems. Findings identify essential organizational and managerial supports needed to support service user voice and participation and reinforce the importance of reflexivity in practice and research.

  7. Efficacy of Locust Beans Husk Char in Heavy Metal Sequestration

    OpenAIRE

    Ademola Ayodeji Ajayi-Banji; Temitayo Ewemoje; Adeniyi Ajimo

    2016-01-01

    Most solid waste management schemes minimally consider low concentration biodegradable agricultural waste management, though the environmental impact of this waste category is significant over a time frame. The column-mode study seeks to address the issue by suggesting potential utilisation of post-harvest waste for heavy metal sequestering. Locust beans husk char of 100 and 200 g was employed to inspect removal efficiency, isotherm and kinetic models of some heavy metals at 30, 60, 90, 120 a...

  8. Physicochemical Characterization of various Vietnamese Biomass Residue-derived Biochars (wood, bamboo and risk husk)

    Science.gov (United States)

    Nguyen, Hien

    2016-04-01

    This study compares the physico-chemical characteristics of various biocchars produced from biomass residues in Vietnam such as fired wood, rice husk, and bamboo. Wood biochar (WBC), rice husk biochar (RHBC), and bamboo biochar (BBC) were produced under limited oxygen conditions using equipment available locally in Vietnam, known as a Top-Lift Updraft Drum (TLUD). The three biochars are alkaline with pH around 10, but were found to have quite significantly different physico-chemical characteristics. Surface areas (measured by BET) were found to be very significantly higher for WBC and BBC with 479.34 m2/g and 434.53 m2/g, respectively, compared to RHBC (3.29 m2/g). The SEM images correspond with the BET surface area, showing a smooth surface for RHBC, a hollow surface for BBC, and a rough surface for WBC. Total carbon (TC) of WBC and BBC are above 80%, while RHBC has only 47.95% TC. Despite having different TC, the content of hydrogen among the biochars is similar, ranging from 2.07% to 2.34%, and the ratio of H/C also follows the same trend. Thus, although the biochars are produced by the same method, the various feedstocks lead to different physico-chemical properties. Ongoing work is linking these physico-chemical properties to fertiliser efficiencies in terms of nitrate and ammonia adsorption and retention capacities, in order to design optimal biochar properties for use in fertilisation. Key words: physico-chemical characteristic, biochar, surface area, SEM, total carbon, feedstock

  9. Kinetics and isotherms of Neutral Red adsorption on peanut husk

    Institute of Scientific and Technical Information of China (English)

    HAN Runping; HAN Pan; CAI Zhaohui; ZHAO Zhenhui; TANG Mingsheng

    2008-01-01

    Adsorption of Neutral Red (NR) onto peanut husk in aqueous solutions was investigated at 295 K. Experiments were carded out as function of pH, adsorbent dosage, contact time, and initial concentration. The equilibrium adsorption data were analyzed by Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, and Toth isotherm models. The results indicated that the Toth and Langmuir models provided the best correlation of the experimental data. The adsorption capacity of peanut husk for the removal of NR was determined with the Langmuir and found to be 37.5 mg/g at 295 K. The adsorption kinetic data were modeled using the pseudo-first order, pseudo-second order, and intra-particle diffusion kinetic equations. It was seen that the pseudo-first order and pseudo-second order kinetic equations could describe the adsorption kinetics. The intraparticle diffusion model was also used to express the adsorption process at the two-step stage. It was implied that peanut husk may be suitable as adsorbent material for adsorption of NR from aqueous solutions.

  10. 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.

  11. Fly ash carbon passivation

    Science.gov (United States)

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  12. 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

    ... 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...

  13. Nanoporous Activated Carbon Derived from Rice Husk for High Performance Supercapacitor

    Directory of Open Access Journals (Sweden)

    Huaxing Xu

    2014-01-01

    Full Text Available Nanoporous activated carbon material was produced from the waste rice husks (RHs by precarbonizing RHs and activating with KOH. The morphology, structure, and specific surface area were investigated. The nanoporous carbon has the average pore size of 2.2 nm and high specific area of 2523.4 m2 g−1. The specific capacitance of the nanoporous carbon is calculated to be 250 F g−1 at the current density of 1 A g−1 and remains 80% for 198 F g−1 at the current density of 20 A g−1. The nanoporous carbon electrode exhibits long-term cycle life and could keep stable capacitance till 10,000 cycles. The consistently high specific capacitance, rate capacity, and long-term cycle life ability makes it a potential candidate as electrode material for supercapacitor.

  14. 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.

  15. 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...

  16. Adsorption Studies of Phenol Using Thermally and Chemically Modified Rice Husk as Adsorbents

    Directory of Open Access Journals (Sweden)

    *M. M. Yousaf

    2014-03-01

    Full Text Available Most of the Phenols are hazardous substances and some are supposed to have carcinogenic activity. Thus it is necessary to remove Phenolics and other aromatics from the aqueous ecosystem. Traditional processes for the removal of Phenolics compounds are extraction, adsorption on granulated activated carbon, steam distillation, chemical and bacterial techniques. Literature survey show a number of methods like oxidation, ion exchange, reverse osmosis, electrochemical oxidation and adsorption. Phenol removal by process like, adsorption is the best method of choice as it can remove most of phenols in simple and easy way. In recent past; agricultural by-products such as, maize cob, date stone, apricot Stones, rice bran, and bagass pith have been extensively studied and used as adsorbents for the adsorption of hazardous substances from wastewater. In the present study we tried modified rice husks as potential adsorbents for the removal of Phenol from aqueous system. Batch mode studies were carried out. Isotherm data was generated and fitted in Freundlich and Langmuir equation to explain the phenomenon of adsorption. The adsorption capacities based on Langmuir model (Qm of the 3 adsorbents were found to be 0.81 for raw husk (RH, 0.395 for the Grafted (G and 2.306 mg/g for the Charred (C. The R2 values were 0.92 for raw husk, 0.97 for grafted and 0.91 for charred husk. Based on Freundlich model the adsorption capacities (K were 2.94, 2.29 and 1.25mg/g for Raw husk, grafted husk and charred husk. The R2 values were found to be 0.72, 0.95 and 0.83 for the raw husk, grafted husk and charred husk respectively. Our result showed that modified rice husks could be used as potential adsorbents for Phenol removal from aqueous system.

  17. Effects of ash forming temperature on water-soluble fraction of biomass ash and it’s elements%成灰温度对三种生物质灰及其元素水溶性的影响

    Institute of Scientific and Technical Information of China (English)

    何芳; 于如军; 张毅; 朱继英; 高振强; 孙鹏

    2015-01-01

    The implementation of biomass ash as a fertilizer is beneficial to the sustainable development of agriculture because it can return the elements taken by the plants from soil during the growth. Water solubility of biomass ash together with its elements is a vital property for the fertilizer’s utilization. In this paper, the effects of ash forming temperature on the water solubility of biomass ash and its elements were investigated experimentally. Three typical types of agro-residues in China, i.e. wheat straw, corn stover and rice husk, were chosen for investigation. Materials were collected and the corresponding proximate and elemental analyses were performed. In preparation process, wheat straw and corn stover were milled into powder with the particle size of less than 1 mm. Ashes were prepared in a muffle furnace at different ash forming temperatures in the scope from 400 to 800℃with the temperature interval of 50℃. About 4-5 g of each sample powder and rice husk were put in the crucibles, heated from ambient temperature to ash forming temperature, and then kept at the ash forming temperature for 4 hours in the muffle furnace. After the temperature of the furnace dropped to less than 200℃, the ashes were taken out to the cabinet dryer, cooled to the ambient temperature, and then weighted and sealed in the sample bag for further measurements. It showed that ash contents of wheat straw, corn stover and rice husk decreased significantly with the increase of ash forming temperature. They decreased from 9.8%, 10.9%and 18.4% at 400℃to 6.9%, 8.7%and 16.8%at 800℃respectively. After the preparation of all the ash, two types of measurements were performed. The first was the water solubility measurement of the ashes according to the standard of GB8307-2002. Total ash of about 0.2-0.3 g was put in a beaker of 50 ml and about 25 ml distilled water was added in it. The mixture was heated and boiled for 2 min and then the solution was filtered through a

  18. Production of inorganic pellet binders from fly-ash. Technical report, March 1--May 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Kawatra, S.K.; Eisele, T.C.

    1995-12-31

    Fly-ash is produced by all coal-fired utilities, and it must be removed from the plant exhaust gases, collected, and disposed of. While much work has been done in the past to utilize fly-ash rather than disposing of it, we nevertheless do not find widespread examples of successful industrial utilization. This is because past work has tended to find uses only for high-quality, easily-utilized fly-ashes, which account for less than 25% of the fly-ash that is produced. The main factor which makes fly-ashes unusable is a high unburned carbon content. In this project, physical separation technologies are being used to remove this carbon, and to convert these unusable fly-ashes into usable products. The main application being studied for the processed fly-ash is as a binder for inorganic materials, such as iron-ore pellets. In the second quarter, additional fly-ash samples were collected from the E. D. Edwards station (Bartonville, IL). Experimentation was begun to study the removal of carbon from these fly-ashes by froth flotation, and make and test pellets that use fly-ash as binder. During the current quarter, flotation experiments were continued on the fly- ashes. Three types of ashes were studied: 1. Ash from the disposal pond (``wet`` ash); 2. Dry fly-ash collected directly from the standard burners (``low-carbon`` ash); 3. Dry fly-ash collected from the low-NOx burners (``high-carbon`` ash). Each of these was chemically analyzed, and conventional flotation experiments were carried out to determine the optimum reagent dosages for carbon removal. Decarbonized ashes were then made from each ash type, in sufficient quantity to be used in pelletization experiments.

  19. Geopolymer Mortar with Fly Ash

    Directory of Open Access Journals (Sweden)

    Saloma

    2016-01-01

    Full Text Available The cement industry accounts for about 7% of all CO2 emissions caused by humans. Therefore, it is necessary to find another material in order to support sustainable material. An alternative way is replacing cement material with alternative material as fly ash. Fly ash as binder need to be added alkaline activator in the form of sodium silicate (Na2SiO3 or potassium silicate (K2SiO3 and sodium hydroxide (NaOH or potassium hydroxide (KOH. The purpose of this research is to analyze the effect of activator liquid concentration on geopolymer mortar properties and to know the value of compressive strength. Molarity variation of NaOH are 8, 12, 14, and 16 M with ratio of Na2SiO3/NaOH = 1.0. Ratio of sand/fly ash = 2.75 and ratio of activator/fly ash = 0.8. The cube-shaped specimen 50 × 50 × 50 mm is cured by steam curing with a temperature of 60°C for 48 hours. The experimental result of fresh mortar reported that the molarity of NaOH affect the slump flow and setting time, higher of NaOH produces the smaller value of slump and the faster time of setting. The experimental of density results reported that the increase of specific gravity when the molarity of NaOH increased. The experimental results of the compressive strength are showed that the maximum compressive strength of geopolymer mortar 14 M is 10.06 MPa and the lowest compressive strength produced by geopolymer mortar 8 M is 3.95 MPa. Testing the compressive strength of geopolymer mortar 16 M produces compressive strength lower than 14 M geopolymer mortar is 9.16 MPa.

  20. Comparative study on the characteristics of fly ash and bottom ash geopolymers.

    Science.gov (United States)

    Chindaprasirt, Prinya; Jaturapitakkul, Chai; Chalee, Wichian; Rattanasak, Ubolluk

    2009-02-01

    This research was conducted to compare geopolymers made from fly ash and ground bottom ash. Sodium hydroxide (NaOH) and sodium silicate (Na(2)SiO(3)) solutions were used as activators. A mass ratio of 1.5 Na(2)SiO(3)/NaOH and three concentrations of NaOH (5, 10, and 15M) were used; the geopolymers were cured at 65 degrees C for 48 h. A Fourier transform infrared spectrometer (FT-IR), differential scanning calorimeter (DSC), and scanning electron microscope (SEM) were used on the geopolymer pastes. Geopolymer mortars were also prepared in order to investigate compressive strength. The results show that both fly ash and bottom ash can be utilized as source materials for the production of geopolymers. The properties of the geopolymers are dependent on source materials and the NaOH concentration. Fly ash is more reactive and produces a higher degree of geopolymerization in comparison with bottom ash. The moderate NaOH concentration of 10 M is found to be suitable and gives fly ash and bottom ash geopolymer mortars with compressive strengths of 35 and 18 MPa.

  1. 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.

  2. Recovering germanium from coal ash by chlorination with ammonium chloride

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new process of enriching germanium from coal ash was developed. The process involves in mixing the coal ash and ammonium chloride and then roasting the mixture to produce germanium chloride that is then absorbed by dilute hydrochloric acid and hydrolyzed to germanium oxide. The germanium recovery reached to 80.2% at the optimum condition: mass ratio of NH4Cl/coal ash is 0.15, roasting temperature 400℃ and roasting time 90 min.

  3. Nutritive Value of Coffee Husk Fermented with Pleurotus ostreatus as Ruminant Feed

    Directory of Open Access Journals (Sweden)

    I. Badarina

    2013-04-01

    Full Text Available Coffee husks is an abundant crop residue but the content of anti nutritional substances such as caffeine, tannin, and lignin limit its utilization as feed ingredients. Higher fungi such as Pleurotus ostreatus have the ability to biotransform lignocellulosic materials through their extracellular enzyme activities. This study was carried out to assess the effect of solid state fermentation by using P. ostreatus on nutrient composition of coffee husk and to evaluate its potency as ruminant feed in vitro. The in vitro experiment was conducted to determine fermentability of treated coffee husk. The usage rate of fermented coffee husk was mimicked feeding level to mid lactation dairy cows; 0%, 10%, 20%, 30%, and 40% (R0 to R4. Fermentation of coffee husk by P. ostreatus increased its protein, from 10.36% to 12.14%, and cellulose, from 19.51% to 24.80%, and decreased its lignin, from 65.42% to 45.04%, tannin from 1.02% to 0.18%, and caffeine, from 1.39% to 0.20%, concentrations. There were no differences in ruminal pH and N-ammonia production but volatile fatty acid production and dry matter digestibility decreased as the fermented coffee husk level increased. The ruminal protozoa population in fermented coffee husk diets was lower than the control diets (P<0.05. In conclusion, it is possible to use 20% of fermented coffee husk in the ration.

  4. 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.

  5. 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.

  6. Synthesis and characterization of LTA nanozeolite using barley husk silica: Mercury removal from standard and real solutions

    Energy Technology Data Exchange (ETDEWEB)

    Azizi, Seyed Naser, E-mail: azizi@umz.ac.ir [Analytical Division, Faculty of Chemistry, University of Mazandaran, P.O. Box: 47416-95447, Babolsar (Iran, Islamic Republic of); Dehnavi, Ahmad Roozbehani, E-mail: Roozbehanisulfur@yahoo.com [Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of); Joorabdoozha, Amir [Analytical Division, Faculty of Chemistry, University of Mazandaran, P.O. Box: 47416-95447, Babolsar (Iran, Islamic Republic of)

    2013-05-15

    Highlights: ► Silica extraction from barley husk with high purity for the synthesis of A nanozeolite. ► Free template A nanozeolite synthesized via new source of silica at low temperature. ► Optimization of SiO{sub 2}/Al{sub 2}O{sub 3}, Na{sub 2}O/SiO{sub 2} ratios, temperature and time of the synthesis. ► Utilizing of synthesized A nanozeolite for mercury removal from aqueous solutions. ► Mercury removal at optimized pH, contact time and adsorbent dose from real solution. - Abstract: In this study, synthesized Lined Type A (LTA) nanozeolite from barley husk silica (BHS) was used for mercury removal from standard and real aqueous solutions. The BHS in amorphous phase with 80% purity was extracted from barley husk ash (BHA), and used effectively as a new source of silica for the synthesis of NaA nanozeolite. The NaA nanocrystal in pure phase has been synthesized at low temperature, without adding any organic additives. The effects of heating time, reaction temperature, SiO{sub 2}/Al{sub 2}O{sub 3}, and Na{sub 2}O/SiO{sub 2} mole ratios on the crystallization of NaA nanozeolite were studied. The adsorption capacity of mercury (II) was studied as a function of pH, contact time, and amount of adsorbent. The crystallization of NaA nanozeolite from BHS was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Brunauer–Emmett–Teller (BET), and FTIR techniques. Moreover, concentration of Hg{sup 2+} ions in the aqueous solutions was analyzed by hydride generation atomic absorption spectroscopy method (HG-AAS). The standard and real samples analysis showed that NaA nanozeolite is capable of Hg{sup 2+} ions removal from the aqueous solutions. Efficiency of mercury (II) adsorption from real solutions onto the nano-sized NaA zeolite was 98%.

  7. 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.

  8. Effect of recycling on properties of rice husk-filled-polypropylene

    Directory of Open Access Journals (Sweden)

    Jutarat Prachayawarakorn

    2005-03-01

    Full Text Available This research concerned with the use of rice husk (Oryza sativa as a filler for polypropylene and its recycle ability. Rice husk (200 mesh and 40% by weight and polypropylene were compounded in a twinscrew extruder and injection moulding technique was applied in order to obtain testing specimens. It was found that tensile, flexural and impact properties as well as % water absorption of the rice husk-filled polypropylene were only slightly dropped upon recycling process, presenting the ability of the rice husk- filledpolypropylene samples to recycle. The increase in melt flow index of the samples was also obtained. In addition, SEM micrographs revealed the reduction of rice husk particle size by the recycling process. Moreover, FTIR spectroscopy and TGA technique were performed for characterizing the filled specimens.

  9. Development of ricehusk ash reinforced bismaleimide toughened epoxy nanocomposites.

    Directory of Open Access Journals (Sweden)

    Kanimozhi eK

    2014-09-01

    Full Text Available AbstractRecent past decades have witnessed remarkable advances in composites with potentialapplications in biomedical devices, aerospace, textiles, civil engineering, energy, electronicengineering, and household products. Thermoset polymer composites have further enhancedand broadened the area of applications of composites. In the present work epoxy-BMItoughened-silica hybrid (RHA/DGEBA-BMI was prepared using bismaleimide astoughener, bisphenol-A as matrix and a silica precursor derived from rice husk ash asreinforcement with glycidoxypropyltrimethoxysilane as coupling agent. Differential scanningcalorimetry, electron microscopy, thermogravimetric analysis, and goniometry were used tocharacterize RHA/DGEBA-BMI composites developed in the present work. Tensile, impactand flexural strength, tensile and flexural modulus, hardness, dielectric properties were alsostudied and discussed. The hybrid nanocomposites possess the higher values of the glasstransition temperature (Tg and mechanical properties than those of neat epoxy matrix.

  10. Development of ricehusk ash reinforced bismaleimide toughened epoxy nanocomposites.

    Science.gov (United States)

    K, Kanimozhi; Sethuraman, K.; V, Selvaraj; Alagar, Muthukaruppan

    2014-09-01

    Abstract Recent past decades have witnessed remarkable advances in composites with potential applications in biomedical devices, aerospace, textiles, civil engineering, energy, electronic engineering, and household products. Thermoset polymer composites have further enhanced and broadened the area of applications of composites. In the present work epoxy-BMI toughened-silica hybrid (RHA/DGEBA-BMI) was prepared using bismaleimide as toughener, bisphenol-A as matrix and a silica precursor derived from rice husk ash as reinforcement with glycidoxypropyltrimethoxysilane as coupling agent. Differential scanning calorimetry, electron microscopy, thermogravimetric analysis, and goniometry were used to characterize RHA/DGEBA-BMI composites developed in the present work. Tensile, impact and flexural strength, tensile and flexural modulus, hardness, dielectric properties were also studied and discussed. The hybrid nanocomposites possess the higher values of the glass transition temperature (Tg) and mechanical properties than those of neat epoxy matrix.

  11. Utilization options for fly ash, bottom ash, and slag in Eastern Europe

    Energy Technology Data Exchange (ETDEWEB)

    Manz, O.E.

    1995-12-01

    Since 1967, at least six ash utilization symposiums have been held in the United States, with papers presented by several European authors on the utilization of coal by-products in Eastern Europe. There is currently over 80,000 megawatts of installed coal-fired capacity available in that region. Unfortunately, of the 117,778,000 tonnes of fly ash, bottom ash, and slag produced in Eastern Europe in 1989, only 13% was utilized. This paper outlines the research and levels and kinds of coal by-product utilization taking place in Eastern Europe since the late 1960s.

  12. 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.

  13. 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......-firing, the model only had a qualitative agreement with the measured ash deposit formation rates.Sintering measurements were carried out by means of compression strength testing of ash pellets. This method showed to not be applicable for the salt rich fly ash derived from straw combustion. For the fly ashes...

  14. FUNDAMENTAL STUDY OF LOW-NOx COMBUSTION FLY ASH UTILIZATION

    Energy Technology Data Exchange (ETDEWEB)

    ERIC M. SUUBERG; ROBERT H. HURT

    1998-10-19

    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 fifty 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.

  15. Possible use of psyllium husk as a release retardant

    Directory of Open Access Journals (Sweden)

    Desai Angira

    2007-01-01

    Full Text Available Various hydrophilic polymers from synthetic origin such as methylcellulose, PEGs, HPMC as well as those from natural world such as guar gum, tragacanth, xanthan gum have been used to formulate oral sustained release formulations. Psyllium husk has the ability to swell 10-14 times of its original volume and form a hydrogel. It is biocompatible, inexpensive, inert, non-absorbable, environment friendly and easily available. However, its use as a release retardant has not been fully explored. Owing to large dose, high sensitivity to light, moisture and heat and also very short half-life of 1-2 h; formulation of sustained release dosage form of amoxicillin trihydrate is a challenge. Hence the present study has been undertaken to develop sustained release granules as well as matrix tablets of amoxicillin trihydrate using psyllium husk as a primary release retardant. The drug release of these formulations was compared with those containing HPMC K4M.The results showed insignificant difference in t80% value for drug release as assessed by student′s t-test at 5% level of significance. Selected formulations were kept at controlled conditions of 40o/75% RH and 30o/65% RH for a period of 3 mo. Microbiological assay was used as a stability indicating method of assay. Sustained release granules and tablet formulations containing HPMC alone were found to be more stable than the similar formulations containing husk with percent drug content at the end of 3 mo at 40o/ 75% RH being 92.66%, 93.81%, 86.74%, 88.31% and the rate of degradation being 8.46x10-4 d-1, 7.1x10-4 d-1, 1.58x10-3 d-1 and 1.38x10-3 d-1, respectively. Thus it was concluded that psyllium husk can be effectively used as a hydrogel polymer in sustained release formulations. However, there is a need to keep moisture level under control during and after formulation.

  16. The Effects of Bottom Ash from MSWI Used as Mineral Additions in Concrete

    Directory of Open Access Journals (Sweden)

    Che Amat Roshazita

    2017-01-01

    Full Text Available Municipal solid waste incinerators (MSWI produce by products which can be classified as bottom and fly ashes. The bottom ash accounts for 85–90 % of the solid product resulting from MSW combustion. The aimed of the present work is to study the effect of replacing partial of bottom ash were manufactured. Fresh and hardened properties of the concrete were compared in order to study the suitable cement-bottom ash replacement. Bottom ash was found to have some reactivity, but without greatly affecting the hydration process of OPC at 10 % replacement. However at more than 10 % replacement, the addition of bottom ash greatly affected strength.

  17. Regular Recycling of Wood Ash to Prevent Waste Production (RecAsh). Technical Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Lars E-mail: lars.t.andersson@skogsstyreslen.se

    2007-03-15

    At present, the extraction of harvest residues is predicted to increase in Sweden and Finland. As an effect of the intensified harvesting, the export of nutrients and acid buffering substances from the growth site is also increased. Wood ash could be used to compensate forest soils for such losses. Most wood fuel ash is today often deposited in landfills. If the wood ash is recycled, wood energy is produced without any significant waste production. Ash recycling would therefore contribute to decreasing the production of waste, and to maintaining the chemical quality of forest waters and biological productivity of forest soils in the long term. The project has developed, analysed and demonstrated two regular ash-recycling systems. It has also distributed knowledge gathered about motives for ash recycling as well as technical and administrative solutions through a range of media (handbooks, workshops, field demonstrations, reports, web page and information videos). Hopefully, the project will contribute to decreasing waste problems related to bio-energy production in the EU at large. The project has been organised as a separate structure at the beneficiary and divided in four geographically defined subprojects, one in Finland and three in Sweden (Central Sweden, Northern Sweden, and South-western Sweden). The work in each subproject has been lead by a subproject leader. Each subproject has organised a regional reference group. A project steering committee has been established consisting of senior officials from all concerned partners. The project had nine main tasks with the following main expected deliverables and output: 1. Development of two complete full-scale ash-recycling systems; 2. Production of handbooks of the ash recycling system; 3. Ash classification study to support national actions for recommendations; 4. Organise regional demonstrations of various technical options for ash treatment and spreading; 5. Organise national seminars and demonstrations of

  18. Preparation of food grade carboxymethyl cellulose from corn husk agrowaste.

    Science.gov (United States)

    Mondal, Md Ibrahim H; Yeasmin, Mst Sarmina; Rahman, Md Saifur

    2015-08-01

    Alpha-cellulose extracted from corn husks was used as the raw material for the production of food-grade carboxymethyl cellulose (CMC). Preparation of CMC from husk cellulose was carried out by an etherification process, using sodium hydroxide and monochloroacetic acid (MCA), with ethanol as the supporting medium. Characterizations of CMC were carried out by analyzing the spectra of FTIR, XRD patterns and SEM photomicrographs. Degree of substitution (DS) was determined with respect to particle size using chemical methods. Solubility, molecular weight and DS of CMC increased with decreased cellulose particle sizes. Microbiological testing of the prepared CMC was done by the pour plate method. Concentrations of heavy metals such as arsenic, lead, cadmium and mercury in the purified CMC were measured by Atomic Absorption Spectroscopy technique and found to be within the WHO/FAO recommended value. A comparative study with CMC available in the international market was conducted. The purity of the prepared CMC was higher, at 99.99% well above the purity of 99.5% for standard CMC. High purity CMC showed a yield 2.4 g/g with DS 2.41, water holding capacity 5.11 g/g, oil holding capacity 1.59 g/g. The obtained product is well suited for pharmaceutical and food additives.

  19. Production of activated carbon from rice husk Vietnam

    Science.gov (United States)

    Korobochkin, V. V.; Tu, N. V.; Hieu, N. M.

    2016-09-01

    This work is dedicated to the production of activated carbon from rice husk from Delta of the Red River in Viet Nam. At the first stage, carbonization of a rice husk was carried out to obtain material containing 43.1% carbon and 25 % silica with a specific surface area of 51.5 m2/g. After separating of silica (the second stage), the specific surface area of the product increased to 204 m2/g and the silica content decreased to 1.23% by weight as well. The most important stage in the formation of the porous structure of the material is the activation. The products with the high specific surface area in the range of 800-1345 m2/g were obtained by activation of carbonized product with water vapour or carbon dioxide at temperatures of 700 °C and 850 °C, with varying the flow rate of the activating agent and activation time. The best results were achieved by activation of carbon material with water vapour at the flow rate of 0.08 dm3/min per 500 g of material and the temperature of 850 °C.

  20. SUNFLOWER HUSKS AS A SOURCE OF FUNCTIONAL FEED ADDITIVES

    Directory of Open Access Journals (Sweden)

    Khusid S. B.

    2015-03-01

    Full Text Available The article describes the results of the complex feed additive based on sunflower husk, enriched with beer wort with the addition of pumpkin pulp. We have studied the chemical composition of sunflower husk, which is the secondary resource of the processing plant raw material, selected methods of enrichment of this raw material with the help of fungi Trichoderma harzianum. Cellulolytic enzyme preparations on the basis of fungi of the genus Trichoderma for use in agriculture and animal feed production is often obtained when the surface method of cultivation. These drugs are cheap and contain a significant number of related hydrolytic enzymes, 29 such as amylase, protease, pectinase and hemicellulase, which are also important and valuable to the consumer. As a vitamin component of the feed additive we have selected a pumpkin pulp, which is a valuable feed for livestock and poultry is a source of carotene, fat and nitrogenous substances. We have also developed elements of technology for complex feed additive. We have created a comprehensive feed additive which can be used in the composition of diets in the feeding of farm animals and poultry

  1. Efficacy of Locust Beans Husk Char in Heavy Metal Sequestration

    Directory of Open Access Journals (Sweden)

    Ademola Ayodeji Ajayi-Banji

    2016-03-01

    Full Text Available Most solid waste management schemes minimally consider low concentration biodegradable agricultural waste management, though the environmental impact of this waste category is significant over a time frame. The column-mode study seeks to address the issue by suggesting potential utilisation of post-harvest waste for heavy metal sequestering. Locust beans husk char of 100 and 200 g was employed to inspect removal efficiency, isotherm and kinetic models of some heavy metals at 30, 60, 90, 120 and 150 min contact time. Elemental composition of the biosorbent was investigated using the SEM-EDX machine. The results obtained depict that over 85% aluminium and nickel removal was achieved at 150 min detention time. The Freundlich isotherm well described most of the sorbates sorption (R2 ≥ 0.91. The sorption rate equally fitted into the second-order pseudo kinetic model (R2 ≥ 0.88. Ion exchange took place during the sorption. Locust beans husk has promising adsorption potential in heavy metal ions removal from fouled surface water. DOI: http://dx.doi.org/10.5755/j01.erem.71.4.13081

  2. 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.

  3. Effects Of Storage Conditions On The Quality Of Unripe Hazelnuts In The Husk

    Directory of Open Access Journals (Sweden)

    Markuszewski Bogumił

    2015-12-01

    Full Text Available The purpose of the study was to assess the storability of unripe hazelnuts in the husk of four cultivars: ‘Hall’s Giant’, ‘Catalan’, ‘Webb’s Prize Cob’ and ‘Cosford’. The nuts were stored in normal and controlled atmospheres, and in Xtend® bags for three months. A quality assessment was performed based on the following parameters: weight of the nut in the husk and without the husk, weight of the kernel, percentage of nuts with husk attached, dry matter content in kernels, infection with fungal diseases, and the presence of physiological disorders. The study demonstrated that hazelnuts stored in Xtend® bags and under a controlled atmosphere had a higher weight for the nut in the husk and without the husk, as well as a higher weight of the kernel and water content when compared to batches of hazelnuts stored in a normal atmosphere. The percentage of nuts remaining in the husk was also higher when stored under such conditions. For the majority of investigated cultivars the storage in Xtend® bags, and to a lesser extent under normal atmosphere conditions, resulted in a substantial increase in nuts infected with fungal and abiotic diseases. Among investigated cultivars, ‘Hall’s Giant’ turned out to be the most resistant to storage diseases.

  4. 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.

  5. 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.

  6. Production of Flammulina velutipes on coffee husk and coffee spent-ground

    Directory of Open Access Journals (Sweden)

    Leifa Fan

    2001-01-01

    Full Text Available Solid state cultivation (SSC was carried out to evaluate the feasibility of using coffee husk and spent-ground as substrates for the production of edible mushroom Flammulina under different conditions of moisture and spawn rate. The strain of F. velutipes LPB 01 was adapted for a coffee husk extract medium. Best results were obtained with 25% spawn rate, though there was not much difference when lower spawn rates (10-20% were used. Ideal moisture content for mycelial growth was 60% and 55% for coffee husk and spent-ground, respectively. With coffee husk as substrate, first fructification occurred after 25 days of inoculation and the biological efficiency reached about 56% with two flushes after 40 days. With spent-ground as substrate, first fructification occurred 21 days after inoculation and the biological efficiency reached about 78% in 40 days. There was decrease in the caffeine and tannins contents (10.2 and 20.4%, respectively in coffee husk after 40 days. In coffee spent-ground, the tannin contents decreased by 28% after 40 days. These decrease was attributed to the degradation of caffeine or tannins by the culture because these were not adsorbed in the fungal mycelia. Results showed the feasibility of using coffee husk and coffee spent-ground as substrate without any nutritional supplementation for cultivation of edible fungus in SSC. Spent ground appeared better than coffee husk.

  7. 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.

  8. Solid State production of manganese peroxidases using arecanut husk as substrate

    Directory of Open Access Journals (Sweden)

    Akhila Rajan

    2010-06-01

    Full Text Available The lignocellulosic biomass from arecanut husk (Areca catechu Linnaeus was evaluated as a new substrate for cultivation of Phanerochaete chrysosporium and Phanerochaete sp for solid state fermentation of manganese peroxidase (MnP. Arecanut had a moisture content of 79.84 % for ripe nut husk whereas green nut husk had 68.39 % moisture and a pH of 5.0, 3.0 and 7.0 for raw, ripe and dry husk. Reducing sugar content was 14.31, 19.21 and 1.77(mg/g of husk for raw, ripe and dry nut husk, respectively. Non reducing sugar was 1.04(mg/g of husk for raw and 0.68 (mg/g of husk for dry husk. Solid state fermentation carried out at different pH showed optimum enzyme production at pH 6.0 (52.60 IU/g for P.chrysosporium and pH 5.0 (44.08 IU/g for Phanerochaete sp. Optimum temperature was 30 ± 2º C for both the organisms. Lower concentration of MnSO4 (0.1 mM MnSO4 induced maximum enzyme production in P.chrysosporium whereas Phanerochaete sp. required 1 mM MnSO4 for induction. Absence of carbon and nitrogen stimulated enzyme production in P.chrysosporium while Phanerochaete sp. needed nitrogen. Enzyme was partially purified by ammonium sulphate precipitation followed by ion exchange chromatography.

  9. Estimating the frequency of volcanic ash clouds over northern Europe

    Science.gov (United States)

    Watson, E. J.; Swindles, G. T.; Savov, I. P.; Lawson, I. T.; Connor, C. B.; Wilson, J. A.

    2017-02-01

    Fine ash produced during explosive volcanic eruptions can be dispersed over a vast area, where it poses a threat to aviation, human health and infrastructure. Here, we focus on northern Europe, which lies in the principal transport direction for volcanic ash from Iceland, one of the most active volcanic regions in the world. We interrogate existing and newly produced geological and written records of past ash fallout over northern Europe in the last 1000 years and estimate the mean return (repose) interval of a volcanic ash cloud over the region to be 44 ± 7 years. We compare tephra records from mainland northern Europe, Great Britain, Ireland and the Faroe Islands, with records of proximal Icelandic volcanism and suggest that an Icelandic eruption with a Volcanic Explosivity Index rating (VEI) ≥ 4 and a silicic magma composition presents the greatest risk of producing volcanic ash that can reach northern Europe. None of the ash clouds in the European record which have a known source eruption are linked to a source eruption with VEI < 4. Our results suggest that ash clouds are more common over northern Europe than previously proposed and indicate the continued threat of ash deposition across northern Europe from eruptions of both Icelandic and North American volcanoes.

  10. Production of technical silicon and silicon carbide from rice-husk

    Directory of Open Access Journals (Sweden)

    A. Z. Issagulov

    2014-10-01

    Full Text Available In the article there are studied physical and chemical properties of silicon-carbonic raw material – rice-husk, thermophysical characteristics of the process of rice-husk pyrolysis in nonreactive and oxidizing environment; structure and phase composition of products of the rice-husk pyrolysis in interval of temperatures 150 – 850 °С and high temperature pyrolysis in interval of temperatures 900 – 1 500 °С. There are defined the silicon-carbon production conditions, which meet the requirements applicable to charging materials at production of technical silicon and silicon carbide.

  11. Comet assay to assess the genotoxicity of Persian walnut (Juglans regia L.) husks with statistical evaluation.

    Science.gov (United States)

    Petriccione, Milena; Ciniglia, Claudia

    2012-07-01

    The aim of this study was to confirm the utility of the Comet assay as a genotoxicity screening test for evaluating the impact of walnut husk aqueous extract. Phytotoxicity assays using diluted and undiluted walnut husk aqueous extracts were performed on young roots of Raphanus sativus (radish), and the Comet assay was used to evaluate DNA integrity in isolated radish radicle nuclei. The results reveal a dose-dependent accumulation of DNA damage in radish radicles treated with walnut husks water extract and that the Kolmogorov-Smirnov test combined with Johnson SB distribution was the best approach for describing Comet assay data.

  12. Mössbauer characterization of feed coal, ash and fly ash from a thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Reyes Caballero, F.; Martínez Ovalle, S. A., E-mail: s.agustin.martinez@uptc.edu.co; Moreno Gutiérrez, M. [Universidad Pedagógica y Tecnológica de Colombia, UPTC, Grupo de Física Nuclear Aplicada y Simulación (Colombia)

    2015-06-15

    The aim of this work was apply {sup 57}Fe Transmission Mössbauer Spectroscopy at room temperature in order to study the occurrence of iron-containing mineral phases in: 1) feed coal; 2) coal ash, obtained in different stages of the ASTM D3174 standard method; and 3) fly ash, produced when coal is burned in the TERMOPAIPA IV thermal power plant localized in Boyacá, Colombia. According to obtained results, we can conclude the occurrence of pyrite and jarosite in the feed coal; Fe{sup 2+} and Fe{sup 3+} crystalline paramagnetic phases, superparamagnetic hematite and hematite in coal ash; Fe{sup 2+} and Fe{sup 3+} noncrystalline and crystalline phases, magnetite and hematite in fly ash. Precisely, for a basic understanding, this work discusses some the possible transformations that take place during coal combustion.

  13. Granulation of coal fly ash by using different types of granule agents

    Science.gov (United States)

    Agusta, H.; Nisya, F. N.; Iman, R. N.; Bilad, D. B. C.

    2017-05-01

    The use of coal produces about 5% solid pollutant in the form of ash (fly ash and bottom ash). Of the total ash produced, about 10-20% is bottom ash and 80-90% is fly ash. This study was aimed at obtaining a type of adhesive which could be used as a fly granulation material for soil conditioner. The study was conducted at the pilot plant of Surfactant and Bioenergy Research Center (SBRC) LPPM IPB from April to August 2016. The fly ash used in this study was obtained from Kalimantan. A pan granulator was used in fly ash granule making process. Granule agent materials were diluted in the concentration of 5, 10, and 15%. Different types of granule agents, namely SBRC-M, SBRC-T, and SBRC-SC were used. The formed fly ash granules were then analyzed for their physical properties including particle density, fly ash granule pH, fly ash granule durability, and fly ash granule water holding capacity. Results showed that fly ash granules made from 15% of SBRC-M had the highest particle density (0.75 g/cm3). Fly ash granules made with SBRC-M had higher pH (10) than those made by using SBRC-SC adhesive (9.3) and SBRC-T (9). SBRC-T was found as the granule agent material which produced fly ash granules with the highest durability levels on average. In this study, the use of SBRC-M granule agent resulted in higher water holding capacity (WHC) (40.62%) than did SBRC-SC (38.79%) and SBRC-T (36.85%). As a granule agent, compared to SBRC-SC and SBRC-T, SBRC-M could produce fly ash granules with highest particle density, highest pH, good durability, and best water holding capacity.

  14. 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

  15. Effect of wood filler treatment and EBAGMA compatibilizer on morphology and mechanical properties of low density polyethylene/olive husk flour composites

    Directory of Open Access Journals (Sweden)

    2007-07-01

    Full Text Available This paper deals with plastic-wood composites based on low density polyethylene (LDPE and olive husk flour (OHF. The problem of incompatibility between the hydrophilic wood filler and the LDPE hydrophobic matrix was treated by two methods: a chemical modification of the olive husk flour with maleic anhydride to esterify the free hydroxyl groups of the wood components and the use of a compatibilizer agent, i.e. an ethylene-butyl acrylate-glycidyl methacrylate (EBAGMA terpolymer. The changes in the structure, the morphology, and the properties resulting from these treatments were followed by various techniques, especially FTIR spectroscopy, scanning electron microscopy (SEM, tensile measurements and water absorption. The experimental results indicated that both methods, i.e. the chemical treatment of the olive husk flour with maleic anhydride and the inclusion of EBAGMA terpolymer, improved the interactions between the two composite components and promoted better dispersion of the filler in the matrix. Moreover, ultimate tensile properties were also increased. However, the use of EBAGMA terpolymer as compatibilizer produced better enhancement of the properties of LDPE/OHF composites compared to those treated with maleic anhydride.

  16. Surface Modification of Fly Ash for Active Catalysis

    Directory of Open Access Journals (Sweden)

    Deepti Jain

    2013-01-01

    Full Text Available Fly ash based effective solid base catalyst (KF/Al2O3/fly ash473, KF/Al2O3/fly ash673, and KF/Al2O3/fly ash873 was synthesized by loading KF over chemically and thermally activated fly ash. The chemical activation was done by treating fly ash with aluminum nitrate via precipitation method followed by thermal activation at 650°C to increase the alumina content in fly ash. The increased alumina content was confirmed by SEM-EDX analysis. The alumina enriched fly ash was then loaded with KF (10 wt% and calcined at three different temperatures 473 K, 673 K and 873 K. The amount of loaded KF was monitored by XRD, FTIR spectroscopy, SEM-EDX, TEM and Flame Atomic Absorption Spectrophotometer. The catalytic activities of the catalysts were tested in the Claisen-Schmidt condensation of benzaldehyde and 4-methoxybenzaldehyde with 2′-hydroxyacetophenone to produce 2′-hydroxychalcone and 4-methoxy-2′-hydroxychalcone respectively. Higher conversion (83% of benzaldehyde and (89% of 4-methoxybenzaldehyde reveals that among these heterogeneous catalysts KF/Al2O3/fly ash673 is very active.

  17. Sulphation characteristics of paper sludge ash

    Energy Technology Data Exchange (ETDEWEB)

    Roh, S.A. [Environmental Systems Research Center, Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of); Kim, S.D. [Environmental Systems Research Center, Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of). Dept. of Chemical and Biomolecular Engineering

    2007-04-15

    Landfills are no longer a viable solution for the disposal of sludge produced from waste water treatment plants because of the decrease in available space, rising fees and growing environmental concerns. However, thermal utilization of this waste may be an economic and sustainable disposal solution. Co-combustion of low heating value sludge with fossil fuels has a positive effect for sulfur dioxide (SO{sub 2}) emissions due to the low sulphur content of biomass fuels and increased sulphur retention in the ash. The sulphur retention is attributed to the formation of sulphates, such as CaSO{sub 4}, K{sub 2}SO{sub 4} and Na{sub 2}SO{sub 4}. The amount of fuel-ash-related sulphur sorption increases during co-combustion. Therefore, sorbents for sulphur reduction may not be required if proper control of the biomass feed is maintained. This paper presented a study in which the sulphation characteristics of calcium-rich paper sludge ash were determined for the use of co-combustion of biomass and coal. The calcium in the paper sludge ash came from the limestone filler used in the manufacturing process to increase the density and whiteness of the paper at 2 paper mills in Korea. A thermobalance reactor along with XRD and SEM-EDX were used for the analysis of sulphated ash to determine the effects of sulphation temperature, particle size and SO{sub 2} concentration on sulphation conversion. The activation energy and pre-exponential factor of sulphation reaction of sludge ash were determined based on the uniform-reaction model. X-ray diffraction analysis revealed that most of the sulphation compounds were CaSO{sub 4}. The sulphation occurred uniformly throughout the ash and the CaSO{sub 4} did not block the outer pore of the sludge ash. The uniform distributions of CaO and other inert minerals in the ash resulted in uniform sulphation with good penetration of SO{sub 2} into pores of the sludge ash without pore blocking during sulphation of CaO. 13 refs., 1 tab., 9 figs.

  18. FLY ASH: AN ALTERNATIVE TO POWDERED ACTIVATED ...

    African Journals Online (AJOL)

    Preferred Customer

    Also, fly ash has been found to be an efficient adsorbent for water treatment in the removal of ... properties for the removal of metal ions and organics; the residual sludge produced is used in ... investigate the reuse of the adsorbent for better economy of the process. ..... Ogbomoso, Oyo State, Nigeria to complete this article.

  19. 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.

  20. Effects of rice husks and their chars from hydrothermal carbonization on the germination rate and root length of Lepidium sativum

    Science.gov (United States)

    Kern, Jürgen; Mukhina, Irina; Dicke, Christiane; Lanza, Giacomo; Kalderis, Dimitrios

    2015-04-01

    Currently, char substrates gain a lot of interest, since they are being discussed as a component in growing media, which may become one option for the replacement of peat. Among different thermal conversion processes of biomass hydrothermal carbonization (HTC) has been found to produce chars with similar acidic pH values like peat. The question however is, if these hydrochars, which may contain toxic phenolic compounds are suitable to be introduced as a new substitute for peat in horticulture. In this study rice husk were hydrothermally carbonized at 200° C for 6 hours, yielding in hydrochars containing organic contaminants such as phenols and furfurals, which may affect plants and soil organisms. We investigated potential toxic effects on the germination rate and the root length of cress salad (Lepidium sativum) in four fractions: i) soil control, ii) raw rice husk + soil, iii) unwashed rice char + soil and iv) acetone/water washed rice char + soil. It could be shown that phenols and furfurals, which were removed from the hydrochar after washing by 80 to 96% did not affect the germination rate and the root length of the cress plants. The lowest germination rate and root length were found in the soil control, the highest in the non-washed hydrochar treatment, indicating a fertilization effect and growth stimulation of cress salad by hydrochar. If this result can be confirmed for other target and non-target organisms in future studies, a new strategy for the production of growing media may be developed.

  1. Characteristics of spanish fly ashes

    Directory of Open Access Journals (Sweden)

    de Luxán, M. P.

    1988-03-01

    Full Text Available The purpose of this study is the characterization of fly ashes produced by Spanish thermoelectric power plants, according to sampling taken in 1981 and 1982. The study takes in the following characteristics: physical characteristics (size distribution of particles, ...; chemical ones (chemical analysis...; and mineralogical ones (application of instrumental techniques of X-ray diffraction and infrared absorption spectroscopy. From a general point of view, it can be said that the samples of Spanish fly ashes are similar to those produced in other countries. The results obtained are a contribution to the knowledge of Spanish fly ashes and form part of the antecedents of investigations carried out in subsequent years.

    Este trabajo tiene por objeto la caracterización de las cenizas volantes producidas en las Centrales Termoeléctricas españolas, según un muestreo realizado entre 1981 y 1982. El estudio comprende las siguientes características: físicas (distribución del tamaño de partículas,...; químicas (análisis químico, …; y mineralógicas (aplicación de las técnicas instrumentales de difracción de rayos X y espectroscopía de absorción infrarroja. Desde un punto de vista general, se puede afirmar que las muestras de ceniza volante estudiadas son semejantes a las producidas en otros países. Los resultados obtenidos son una aportación al conocimiento de las cenizas volantes españolas y forman parte de los antecedentes de las investigaciones llevadas a cabo en años posteriores.

  2. Fusion characterization of biomass ash

    DEFF Research Database (Denmark)

    Ma, Teng; Fan, Chuigang; Hao, Lifang

    2016-01-01

    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, Tm, 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....

  3. 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.

  4. 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...

  5. Juglone Content in Leaf and Green Husk of Five Walnut (Juglans regia L. Cultivars

    Directory of Open Access Journals (Sweden)

    Sina Niculina COSMULESCU

    2011-05-01

    Full Text Available Juglone (5-hydroxy-1,4-napthoquinone is a chemical compound released by walnut trees that can be toxic for surrounding plant species. In the present study, juglone was identified in leaves and green husk in five walnut cultivars: Germisara, Jupanesti, Franquette, Vina, Valcor by using high performance liquid chromatography (HPLC-RP. Juglone was found predominant in green husk (average value of cultivars is about 31.308 mg/100 g. Significant differences in contents of identified juglone were observed among cultivars that ranged from 20.56 to 42.78 mg/100g for green husk, and 5.42 to 22.82 mg/100 g for leaves. It was also found that walnut green husk and leaves represent the most important source of walnut phenolics.

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

    African Journals Online (AJOL)

    Michael Horsfall

    Removal of Zn(II) and Pb (II) ions Using Rice Husk in Food Industrial Wastewater. *ASRARI, ELHAM; TAVALLALI ... Payame Noor University (PNU), Shiraz, 711955 -1368, Iran ... need to reconsider consumption patterns and the way resources ...

  7. 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.

  8. Use of psyllium (isubgol) husk as an alternative gelling agent for the ...

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... microalgae (Cyanobacteria) Chroococcus limneticus and eukaryotic green ... psyllium husk were far lower than 722000 cells mL-1 on agar gelled ..... Evidence for the recognition of a secondary structure of carrageenan.

  9. Nutritive Value of Coffee Husk Fermented with Pleurotus ostreatus as Ruminant Feed

    OpenAIRE

    I. Badarina; D. Evvyernie; T. Toharmat; E. N. Herliyana; L. K. Darusman

    2013-01-01

    Coffee husks is an abundant crop residue but the content of anti nutritional substances such as caffeine, tannin, and lignin limit its utilization as feed ingredients. Higher fungi such as Pleurotus ostreatus have the ability to biotransform lignocellulosic materials through their extracellular enzyme activities. This study was carried out to assess the effect of solid state fermentation by using P. ostreatus on nutrient composition of coffee husk and to evaluate its potency as ruminant feed ...

  10. 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...... analysis into three main groups depending upon their ash content of silica, alkali metal, and calcium and magnesium. To further detail the biomass classification, the relative molar ratio of Cl, S, and P to alkali were included. The study has led to knowledge on biomass fuel ash composition influence...... on ash transformation, ash deposit flux, and deposit chlorine content when biomass fuels are applied for suspension combustion....

  11. The Effect of Various Acids on Properties of Microcrystalline Cellulose (MCC) Extracted from Rice Husk (RH)

    Science.gov (United States)

    Nur Hanani, A. S.; Zuliahani, A.; Nawawi, W. I.; Razif, N.; Rozyanty, A. R.

    2017-05-01

    Microcrystalline cellulose (MCC) was successfully extracted from rice husk (RH) via acid hydrolysis process using nitric acid (HNO3) in comparison with sulphuric acid (H2SO4) and hydrochloric acid (HCl). MCC-RH extracted using HNO3 produced the highest percentage yield at 83.5% as compared to H2SO4 and HCl at 80.6% and 81.8% respectively. Analysis of Fourier Transform Infrared (FTIR) spectroscopy affirmed the successive elimination of non-cellulosic material from RH cellulose resulting highly purified MCC-RH. X-ray Diffraction (XRD) analysis showed MCC-RH treated with HCl gives the highest crystallinity index value of 54.2% while HNO3 and H2SO4 produced comparable results of 52.4% and 49.7% respectively. The results indicate successive extraction of MCC-RH using HNO3 that has great potential to replace strong acid such as H2SO4 and HCl in acid hydrolysis.

  12. Production of bacterial cellulose by Gluconacetobacter hansenii UAC09 using coffee cherry husk.

    Science.gov (United States)

    Rani, M Usha; Appaiah, K A Anu

    2013-08-01

    The work is aimed to investigate the suitability of underutilized coffee cherry husk (CCH) for the production and optimization of bacterial cellulose (BC) by Gluconacetobacter hansenii UAC09 and to study the physico-mechanical properties of BC films. CCH extract was used as a carbon source in various concentrations along with other nutritional components such as nitrogen (corn steep liquor, urea) and additives (ethyl alcohol, acetic acid). Concentration of CCH extract at 1:1 (w/v) along with 8% (v/v) corn steep liquor, 0.2% (w/v) urea, combination of 1.5% ethyl alcohol and 1.0% (v/v) acetic acid resulted in the production of 5.6-8.2 g/L of BC. BC had tensile strength varying between 28.5 and 42.4 MPa. BC produced with CCH and Hestrin and Schramm (HS) media did not differ in structure as analyzed by FT-IR. Scanning electron microscopic studies indicated BC to contain reticulated network of fine fibers. Under optimized condition, based on the other additives, CCH produced more than three folds yield of BC (5.6-8.2 g/L) than control medium (1.5 g/L). This is the first report on the use of CCH for the production of BC and paved way for the utilization of organic wastes with pectin and high polyphenol content.

  13. Characterization and Stabilisation of Biochars Obtained from Empty Fruit Bunch, Wood, and Rice Husk

    Directory of Open Access Journals (Sweden)

    Hamdan Jol

    2014-04-01

    Full Text Available Agricultural production in Malaysia has been continually growing. Most of the agricultural waste has been discarded or burnt on land; however, these agricultural wastes can serve as a feedstock for biochar production, which contributes an insignificant net amount of carbon dioxide to the atmosphere after soil incorporation. Three kinds of primary biochar were used in this study: empty fruit bunch biochar (EFB, wood biochar (WB, and rice husk biochar (RHB. EFB and WB were produced by slow pyrolysis, whereas RHB was produced by gasification. This study aimed to understand how pyrolysis technologies of native feedstocks impact the chemical characteristics and short-term soil stability of biochar. The kinetic parameters of C-mineralization suggested a tri-phasic C-mineralization process (labile, unstable, and recalcitrant carbon. The estimates indicated the existence of a very labile C-fraction in RHB with a very small decay constant K3. Fourier transform infrared spectroscopy and X-ray diffraction showed the three phases of the biochar, from the microcrystalline C of the labile fraction to the largely amorphous intermediate C of the unstable fraction, and lastly the formation of turbostratic crystallite C in the recalcitrant fraction. It has been concluded that RHB had a higher degree of aromaticity and greater stability, and therefore should be more recalcitrant to biological and chemical degradation.

  14. Electrochemical removal of cadmium from bio-ash; Elektrokemisk fjernelse af cadmium fra bioasker

    Energy Technology Data Exchange (ETDEWEB)

    Juul Pedersen, Anne; Ottosen, Lisbeth M.; Simonsen, Peter; Christensen, Terkel C.

    2004-07-01

    The potential of using the method electrodialytic remediation for removal of cadmium from bioashes has been investigated. Five different types of fly ash from biomass combustion were included in the study: 1) A straw combustion fly ash from grate-firing at Avedoere power plant. 2) A fly ash from co-firing of wood and fuel oil at Avedoere power plant. 3) A suspended, grain size fractionated straw fly ash, obtained from PSO project FU 2201, fine and coarse size fraction. The ash was originally produced at Avedoere power plant. 4) A straw pellet fly ash from dust-firing at Amager power plant. Thr five ashes were characterised, and a series of preliminary elekctrodialytic remediation experiments were conducted on each ash. In spite a significant differences between the five ashes with respect to parameters such as pH and content of cadmium, all ashes showed promising remediation potential. For all ashes cadmium concentrations below the regulatory limits for recycling were reached in one or more of the preliminary remediation experiements. The best results were obtained with the suspended straw ash from PSO FU 2201, whereas the results with the wood chips ash, due to a high initial pH value, were less sucessful, meaning that the remediation process was progressing more slowly. (BA)

  15. 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

    2012-11-01

    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.

  16. 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.

  17. 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)

  18. Ash fusion temperatures and their association with the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.K.; Wall, T.F.; Gupta, R.P. [Cooperative Research Centre for Black Coal Utilisation, Newcastle, NSW (Australia); Creelman, R.A. [Creelman (R.A.) and Associates, Sydney, NSW (Australia)

    1997-04-01

    Ash deposition on furnace walls in PF (pulverized fuel) furnaces is called slagging when it occurs in the high temperature areas of furnaces directly exposed to flame radiation and fouling in other regions such as tubes in the convection section of the boiler. There are well documented shortcomings of certain approaches relating to their uncertainties as predictive tools for plant performance such as poor repeatability and re-producibility of ash fusion measurements. The nature of physical and chemical changes occurring during melting of coal ash has been investigated in the current study to provide an alternative procedure to the ash fusion test. Shrinkage measurements are frequently used in metallurgy and ceramic science to study the physical properties of materials at high temperatures. The output of this experiment provides three to four `peaks` (maximum rate of shrinkage with temperature) of different intensity and at different temperatures which are related to melting characteristics of the sample. It was concluded that shrinkage extents exceeding 50 percent indicated that the effect of the ash particle size is of secondary importance compared to ash chemistry in determining shrinkage levels, with fine particles giving rapid shrinkage events 10 degrees C lower in temperature. (author). 7 figs., refs.

  19. Physiological responses of emerald ash borer larvae to feeding on different ash species reveal putative resistance mechanisms and insect counter-adaptations.

    Science.gov (United States)

    Rigsby, C M; Showalter, D N; Herms, D A; Koch, J L; Bonello, P; Cipollini, D

    2015-07-01

    Emerald ash borer, Agrilus planipennis Fairmaire, an Asian wood-boring beetle, has devastated ash (Fraxinus spp.) trees in North American forests and landscapes since its discovery there in 2002. In this study, we collected living larvae from EAB-resistant Manchurian ash (Fraxinus mandschurica), and susceptible white (Fraxinus americana) and green (Fraxinus pennsylvanica) ash hosts, and quantified the activity and production of selected detoxification, digestive, and antioxidant enzymes. We hypothesized that differences in larval physiology could be used to infer resistance mechanisms of ash. We found no differences in cytochrome P450, glutathione-S-transferase, carboxylesterase, sulfotransferase, and tryptic BApNAase activities between larvae feeding on different hosts. Despite this, Manchurian ash-fed larvae produced a single isozyme of low electrophoretic mobility that was not produced in white or green ash-fed larvae. Additionally, larvae feeding on white and green ash produced two serine protease isozymes of high electrophoretic mobility that were not observed in Manchurian ash-fed larvae. We also found lower activity of β-glucosidase and higher activities of monoamine oxidase, ortho-quinone reductase, catalase, superoxide dismutase, and glutathione reductase in Manchurian ash-fed larvae compared to larvae that had fed on susceptible ash. A single isozyme was detected for both catalase and superoxide dismutase in all larval groups. The activities of the quinone-protective and antioxidant enzymes are consistent with the resistance phenotype of the host species, with the highest activities measured in larvae feeding on resistant Manchurian ash. We conclude that larvae feeding on Manchurian ash could be under quinone and oxidative stress, suggesting these may be potential mechanisms of resistance of Manchurian ash to EAB larvae, and that quinone-protective and antioxidant enzymes are important counter-adaptations of larvae for dealing with these resistance

  20. MAT 126 ASH Course Tutorial / Tutorialoutlet

    OpenAIRE

    stylia

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   MAT 126 Week 1 DQ 1 (Ash) MAT 126 Week 1 Quiz (Ash) MAT 126 Week 1 Written Assignment (Arithmetic and geometric sequence) (Ash) MAT 126 Week 2 DQ 1 (Ash) MAT 126 Week 2 DQ 2 (Ash) MAT 126 Week 2 Assignment Is It Fat Free (Ash) MAT 126 Week 2 Quiz (Ash) MAT 126 Week 3 DQ 1 (Ash) MAT 126 Week 3 DQ 2 (Ash) MAT 126 Week 3 Assignment Quadratic Equations (Ash) MAT 126 Week 3 Quiz (Ash) MAT 126...

  1. 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.

  2. Soil food web structure after wood ash application

    DEFF Research Database (Denmark)

    Mortensen, Louise Hindborg; Qin, Jiayi; Cruz-Paredes, Carla

    the consequences of returning wood ash to biofuel producing coniferous forest. We that the change in pH and increased availability of nutrients after ash application to forest floor can facilitate an increase in the bacteria to fungi ratio with possible effects for the soil food by applying ash of different......In 2006, the European Council established a mandatory target of 20 % renewable energy of consumption by 2020. Part of the replacement is burning biomass for heating and electricity. ~ Whole tree biomass harvesting for biofuel combustion intensifies removal of nutrients from the by applying ash from...... the combustion back to the system and thus recycle the besides being rich in inorganic nutrients, ash is also very alkaline and contains heavy metals. The ASHBACK project (www.ashback.dk) is a cooperation between three Danish universities other research institutions and stake-holders that aims to investigate...

  3. Soil food web structure after wood ash application

    DEFF Research Database (Denmark)

    Mortensen, L. H.; Qin, J.; Krogh, Paul Henning

    of nutrients from the ecosystem. This can be partly mitigated by applying ash from the combustion back to the system and thus recycle the nutrients. However, besides being rich in inorganic nutrients, ash is also very alkaline and contains heavy metals. The ASHBACK project (www.ashback.dk) is a cooperation...... between three Danish universities, other research institutions and stake-holders that aims to investigate the consequences of returning wood ash to biofuel producing coniferous forest. We hypothesize that the change in pH and increased availability of nutrients after ash application to the forest floor...... can facilitate an increase in the bacteria to fungi ratio with possible cascading effects for the soil food web structure. This is tested by applying ash of different concentrations to experimental plots in a coniferous forest. During the course of the project soil samples will be collected...

  4. Synthesis and characterization of zeolites prepared from industrial fly ash

    OpenAIRE

    Franus, Wojciech; Wdowin, Magdalena; Franus, Małgorzata

    2014-01-01

    In this paper, we present the possibility of using fly ash to produce synthetic zeolites. The synthesis class F fly ash from the Stalowa Wola SA heat and power plant was subjected to 24 h hydrothermal reaction with sodium hydroxide. Depending on the reaction conditions, three types of synthetic zeolites were formed: Na-X (20 g fly ash, 0.5 dm3 of 3 mol · dm−3 NaOH, 75 °C), Na-P1 (20 g fly ash, 0.5 dm3 of 3 mol · dm−3 NaOH, 95 °C), and sodalite (20 g fly ash, 0.8 dm3 of 5 mol · dm−3 NaOH + 0.4...

  5. Dry coal fly ash cleaning using rotary triboelectrostatic separator

    Institute of Scientific and Technical Information of China (English)

    TAO Daniel; FAN Mao-ming; JIANG Xin-kai

    2009-01-01

    More than 80 million metric tons of fly ash is produced annually in the U.S. As coal combustion by-product. Coal fly ash can be converted to value-added products if unburned carbon is reduced to less than 2.5%. However, most of fly ash is currently landfilled as waste due to lack of efficient purification technologies to separate unburned carbon from fly ash. A rotary triboelectrostatic separator has been developed and patented recently at the University of Kentucky with unique features. Several fly ash samples have been used to understand the effects of major process parameters on the separation performance. The results show that compared to existing triboelectrostatic separators, the rotary triboelectrostatic separator has significant advantages in particle charging efficiency, solids throughput, separation efficiency, applicable particle size range.

  6. Application of Fly Ash from Solid Fuel Combustion in Concrete

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard

    2008-01-01

    reactor to test the impact of changes in operating conditions and fuel type on the AEA adsorption of ash and NOx formation. Increased oxidizing conditions, obtained by improved fuel-air mixing or higher excess air, decreased the AEA requirements of the produced ash by up to a factor of 25. This was due...... on a carbon black. The reactor was modeled with CFD and a relationship between oxygen concentration in the early stage of combustion and the AEA adsorption properties of the ash was observed. The NOx formation increased by up to three times with more oxidizing conditions and thus, there was a trade....... The AEA requirements of a fly ash can be suppressed by exposing it to oxidizing species, which oxidizes the carbon surface and thus prevents the AEA to be adsorbed. In the present work, two fly ashes have been ozonated in a fixed bed reactor and the results showed that ozonation is a potential post...

  7. Failure to phytosanitize ash firewood infested with emerald ash borer in a small dry kiln using ISPM-15 standards.

    Science.gov (United States)

    Goebel, P Charles; Bumgardner, Matthew S; Herms, Daniel A; Sabula, Andrew

    2010-06-01

    Although current USDA-APHIS standards suggest that a core temperature of 71.1 degrees C (160 degrees F) for 75 min is needed to adequately sanitize emerald ash borer, Agrilus planipennis Fairmaire-infested firewood, it is unclear whether more moderate (and economical) treatment regimes will adequately eradicate emerald ash borer larvae and prepupae from ash firewood. We constructed a small dry kiln in an effort to emulate the type of technology a small- to medium-sized firewood producer might use to examine whether treatments with lower temperature and time regimes successfully eliminate emerald ash borer from both spilt and roundwood firewood. Using white ash (Fraxinus americana L.) firewood collected from a stand with a heavy infestation of emerald ash borer in Delaware, OH, we treated the firewood using the following temperature and time regime: 46 degrees C (114.8 degrees F) for 30 min, 46 degrees C (114.8 degrees F) for 60 min, 56 degrees C (132.8 degrees F) for 30 min, and 56 degrees C (132.8 degrees F) for 60 min. Temperatures were recorded for the outer 2.54-cm (1-in.) of firewood. After treatment, all firewood was placed under mesh netting and emerald ash borer were allowed to develop and emerge under natural conditions. No treatments seemed to be successful at eliminating emerald ash borer larvae and perpupae as all treatments (including two nontreated controls) experienced some emerald ash borer emergence. However, the 56 degrees C (132.8 degrees F) treatments did result in considerably less emerald ash borer emergence than the 46 degrees C (114.8 degrees F) treatments. Further investigation is needed to determine whether longer exposure to the higher temperature (56 degrees C) will successfully sanitize emerald ash borer-infested firewood.

  8. Fire severity effects on ash extractable Total Phosphorous

    Science.gov (United States)

    Pereira, Paulo; Úbeda, Xavier; Martin, Deborah

    2010-05-01

    Phosphorous (P) is a crucial element to plant nutrition and limits vegetal production. The amounts of P in soil are lower and great part of this nutrient is absorbed or precipitated. It is well known that fire has important implications on P cycle, that can be lost throughout volatilization, evacuated with the smoke, but also more available to transport after organic matter mineralization imposed by the fire. The release of P depends on ash pH and their chemical and physical characteristics. Fire temperatures impose different severities, according to the specie affected and contact time. Fire severity is often evaluated by ash colour and this is a low-cost and excellent methodology to assess the fire effects on ecosystems. The aim of this work is study the ash properties physical and chemical properties on ash extractable Total Phosphorous (TP), collected in three wildfires, occured in Portugal, (named, (1) Quinta do Conde, (2) Quinta da Areia and (3) Casal do Sapo) composed mainly by Quercus suber and Pinus pinaster trees. The ash colour was assessed using the Munsell color chart. From all three plots we analyzed a total of 102 ash samples and we identified 5 different ash colours, ordered in an increasing order of severity, Very Dark Brown, Black, Dark Grey, Very Dark Grey and Light Grey. In order to observe significant differences between extractable TP and ash colours, we applied an ANOVA One Way test, and considered the differences significant at a p<0.05. The results showed that significant differences in the extractable TP among the different ash colours. Hence, to identify specific differences between each ash colour, we applied a post-hoc Fisher LSD test, significant at a p<0.05. The results obtained showed significant differences between the extractable TP from Very dark Brown and Black ash, produced at lower severities, in relation to Dark Grey, Very Dark Grey and Light Grey ash, generated at higher severities. The means of the first group were higher

  9. Hydration of fly ash cement

    Energy Technology Data Exchange (ETDEWEB)

    Etsuo Sakai; Shigeyoshi Miyahara; Shigenari Ohsawa; Seung-Heun Lee; Masaki Daimon [Tokyo Institute of Technology, Tokyo (Japan). Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering

    2005-06-01

    It is necessary to establish the material design system for the utilization of large amounts of fly ash as blended cement instead of disposing of it as a waste. Cement blended with fly ash is also required as a countermeasure to reduce the amount of CO{sub 2} generation. In this study, the influences of the glass content and the basicity of glass phase on the hydration of fly ash cement were clarified and hydration over a long curing time was characterized. Two kinds of fly ash with different glass content, one with 38.2% and another with 76.6%, were used. The hydration ratio of fly ash was increased by increasing the glass content in fly ash in the specimens cured for 270 days. When the glass content of fly ash is low, the basicity of glass phase tends to decrease. Reactivity of fly ash is controlled by the basicity of the glass phase in fly ash during a period from 28 to 270 days. However, at an age of 360 days, the reaction ratios of fly ash show almost identical values with different glass contents. Fly ash also affected the hydration of cement clinker minerals in fly ash cement. While the hydration of alite was accelerated, that of belite was retarded at a late stage.

  10. 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.

  11. 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...

  12. Post-treatment of Fly Ash by Ozone in a Fixed Bed Reactor

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard; Melia, M. C.; Jensen, Anker Degn

    2009-01-01

    The residual carbon in fly ash produced from pulverized coal combustion can adsorb the air-entraining admixtures (AEAs) added to enhance air entrainment in concrete. This behavior of the ash can be suppressed by exposing the fly ash to oxidizing species, which oxidizes the carbon surface and thus...... prevents the AEA to be adsorbed. In the present work, two fly ashes have been ozonated in a fixed bed reactor and the results showed that ozonation is a potential post-treatment method that can lower the AEA requirements of a fly ash up to 6 times. The kinetics of the carbon oxidation by ozone was found...

  13. 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

  14. Rice Husk Supported Catalysts for Degradation of Chlorobenzenes in Capillary Microreactor

    Directory of Open Access Journals (Sweden)

    Abdulelah Thabet

    2015-01-01

    Full Text Available Chlorinated organic pollutants are persistent, toxic, and ubiquitously distributed environmental contaminants. These compounds are highly bioaccumulative and adversely affect the ozone layer in the atmosphere. As such, their widespread usage is a major cause of environmental and health concern. Therefore, it is important to detoxify such compounds by environment friendly methods. In this work, rice husk supported platinum (RHA-Pt and titanium (RHA-Ti catalysts were used, for the first time, to investigate the detoxification of chlorobenzenes in a glass capillary microreactor. High potential (in kV range was applied to a reaction mixture containing buffer solution in the presence of catalyst. Due to high potential, hydroxyl and hydrogen radicals were produced, and the reaction was monitored by gas chromatography-mass spectrometry. The main advantage of this capillary reactor is the in situ generation of hydrogen for the detoxification of chlorobenzene. Various experimental conditions influencing detoxification were optimized. Reaction performance of capillary microreactor was compared with conventional catalysis. Only 20 min is sufficient to completely detoxify chlorobenzene in capillary microreactor compared to 24 h reaction time in conventional catalytic method. The capillary microreactor is simple, easy to use, and suitable for the detoxification of a wide range of chlorinated organic pollutants.

  15. Synthesis of silicon carbide from rice husk in a dc arc plasma reactor

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, B.B.; Mohanty, B.C.; Singh, S.K. [Regional Research Lab., Bhubaneswar (India)

    1996-05-01

    SiC particles have been synthesized in the {alpha}-phase from a mixture of boiler-burnt rice husk and graphite powder in a dc extended arc plasma reactor on a 200--250 g scale. A SiC yield as high as 72% was achieved at a 3.03:1 carbon-to-silica ratio. 21R polytypism, which is rare to grow, was observed in the SiC. About 90% of the SiC particles produced were found to lie under 163 {micro}m, 50% under 90 {micro}m, and 10% under 28 {micro}m size. Very fine particles under 10 {micro}m size occurred to the extent of 3%. XRD and SEM characterizations were carried out to study the phase and morphology of the particles. Heterogeneous gas-phase reactions seem to be responsible for intermediate-size SiC particle growth in the multitemperature zone dc extended arc plasma reactor.

  16. 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.

  17. Uptake of arsenic by alkaline soils near alkaline coal fly ash disposal facilities.

    Science.gov (United States)

    Khodadoust, Amid P; Theis, Thomas L; Murarka, Ishwar P; Naithani, Pratibha; Babaeivelni, Kamel

    2013-12-01

    The attenuation of arsenic in groundwater near alkaline coal fly ash disposal facilities was evaluated by determining the uptake of arsenic from ash leachates by surrounding alkaline soils. Ten different alkaline soils near a retired coal fly ash impoundment were used in this study with pH ranging from 7.6 to 9.0, while representative coal fly ash samples from two different locations in the coal fly ash impoundment were used to produce two alkaline ash leachates with pH 7.4 and 8.2. The arsenic found in the ash leachates was present as arsenate [As(V)]. Adsorption isotherm experiments were carried out to determine the adsorption parameters required for predicting the uptake of arsenic from the ash leachates. For all soils and leachates, the adsorption of arsenic followed the Langmuir and Freundlich equations, indicative of the favorable adsorption of arsenic from leachates onto all soils. The uptake of arsenic was evaluated as a function of ash leachate characteristics and the soil components. The uptake of arsenic from alkaline ash leachates, which occurred mainly as calcium hydrogen arsenate, increased with increasing clay fraction of soil and with increasing soil organic matter of the alkaline soils. Appreciable uptake of arsenic from alkaline ash leachates with different pH and arsenic concentration was observed for the alkaline soils, thus attenuating the contamination of groundwater downstream of the retired coal fly ash impoundment.

  18. Performance of fly ash concretes in accelerated and natural chloride exposure regimes

    Energy Technology Data Exchange (ETDEWEB)

    Sorn, V.; Oshiro, T.; Yamada, Y. [Ryukyus Univ., Okinawa (Japan). Dept. of Civil Engineering and Architecture; Sugiyama, T. [Gunma Univ. (Japan). Dept. of Civil Engineering; Matsufuji, Y. [Kyusyu Univ. (Japan). Dept. of Architecture

    2001-07-01

    Serious effort has been made in Japan to make use of the huge quantity of fly ash that is generated each year by coal-based thermal power plants. The produced fly ash contains unburned carbon, rendering it a low quality material classified as Japan Industrial Standard A 6201 class 3. The most efficient use of this kind of fly ash is to use it in concrete, where fly ash is added to the concrete without a corresponding reduction in the quantity of cement. A study was conducted to examine the penetrating characteristics of chloride ions into fly ash concrete and the corrosion of steel reinforcement in concrete, where portions of fine and coarse aggregates were replaced by fly ash. Compressive strength tests were conducted along with chloride penetration tests. Corrosion diagnosis of steel reinforcements was also performed. The physical properties and durability of fly ash concrete against aggressive environments was studied. It was determined that fly ash concretes have higher compressive strength than the control concrete. The strength development of fly ash concrete is very large, particularly on high-volume fly ash concretes. Chloride diffusion coefficients of fly ash concretes derived from the rapid chloride permeability test were found to decrease according to the volume of fly ash added. Chloride penetration of fly ash concretes also decreases with an increase in the volume of fly ash added. Corrosion diagnosis of steel reinforcement in concrete was shown to be effective for evaluating corrosive behaviour of steel reinforcement in fly ash concretes. The values of half-cell potential and polarization resistance measured on fly ash concretes become higher, suggesting no corrosion on steel reinforcement. 6 refs., 4 tabs., 10 figs.

  19. MGT 330 ASH Course Tutorial / Tutorialoutlet

    OpenAIRE

    alfoniz

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   MGT 330 Week 1 Individual Assignment Functions of Management Paper (Ash) MGT 330 Week 1 DQ 1 (Ash) MGT 330 Week 1 DQ 2 (Ash) MGT 330 Week 1 DQ 3 (Ash) MGT 330 Week 1 Summary (Ash) MGT 330 Week 2 Team Assignment External Internal Factors Paper (Ash) MGT 330 Week 2 Individual Assignment Delegation (Ash) MGT 330 Week 2 Summary (Ash) MGT 330 Week 2 DQ 1 (Ash) MGT 330 Week 2 DQ 2 (Ash) MGT 330 W...

  20. The Influence of Fiber Length and Concentration on the Physical Properties of Wheat Husk Fibers Rubber Composites

    Directory of Open Access Journals (Sweden)

    Maged S. Sobhy

    2010-01-01

    Full Text Available Ethylene-propylene-diene terpolymer (EPDM/wheat husk fibers (WHFs composites were prepared using a laboratory size two-roll mill. Cure characteristics and some physical properties such as swelling, mechanical, and thermal properties of the vulcanizates were studied. The adhesion status between the WHF and rubber matrix is lacked in general, but it started to reinforce the matrix at higher WHF contents where a higher restriction to molecular motion of the macromolecules with uniformed stress distribution of the fibers is produced. From the TGA analysis, a thermally stable property is exhibited, which in turn partially enhanced the reinforcement of the WHF-EPDM composites due to the natural adhesion during vulcanization.

  1. Hydrogen-rich gas production via CaO sorption-enhanced steam gasification of rice husk: a modelling study.

    Science.gov (United States)

    Beheshti, Sayyed Mohsen; Ghassemi, Hojat; Shahsavan-Markadeh, Rasoul; Fremaux, Sylvain

    2015-01-01

    Gasification is a thermochemical process in which solid or liquid fuels are transformed into synthesis gas through partial oxidation. In this paper, a kinetic model of rice husk gasification has been developed, which is interesting for the applications of the syngas produced. It is a zero-dimensional, steady-state model based on global reaction kinetic, empirical correlation of pyrolysis and is capable of predicting hydrogen yield in the presence of sorbent CaO. The model can also be used as a useful tool to investigate the influence of process parameters including steam/biomass ratio, CaO/fuel ratio (CaO/Fuel), and gasification temperature on hydrogen efficiency, CO2 capture ratio (CCR), and average carbonation conversion (Save). Similar to hydrogen formation, CCR also increases with increasing CaO/Fuel, but an opposite trend is exhibited in Save. Model predictions were compared with available data from the literature, which showed fairly good agreement.

  2. Application of mineral bed materials during fast pyrolysis of rice husk to improve water-soluble organics production.

    Science.gov (United States)

    Li, R; Zhong, Z P; Jin, B S; Zheng, A J

    2012-09-01

    Fast pyrolysis of rice husk was performed in a spout-fluid bed to produce water-soluble organics. The effects of mineral bed materials (red brick, calcite, limestone, and dolomite) on yield and quality of organics were evaluated with the help of principal component analysis (PCA). Compared to quartz sand, red brick, limestone, and dolomite increased the yield of the water-soluble organics by 6-55% and the heating value by 16-19%. The relative content of acetic acid was reduced by 23-43% with calcite, limestone and dolomite when compared with quartz sand. The results from PCA showed all minerals enhanced the ring-opening reactions of cellulose into furans and carbonyl compounds rather than into monomeric sugars. Moreover, calcite, limestone, and dolomite displayed the ability to catalyze the degradation of heavy compounds and the demethoxylation reaction of guaiacols into phenols. Minerals, especially limestone and dolomite, were beneficial to the production of water-soluble organics.

  3. Cocoa pod husk: A new source of CLEA-lipase for preparation of low-cost biodiesel: An optimized process.

    Science.gov (United States)

    Khanahmadi, Soofia; Yusof, Faridah; Chyuan Ong, Hwai; Amid, Azura; Shah, Harmen

    2016-08-10

    Enzymatic reactions involving lipases as catalyst in transesterification can be an excellent alternative to produce environmental-friendly biodiesel. In this study, lipase extracted from Cocoa Pod Husk (CPH) and immobilized through cross linked enzyme aggregate (CLEA) technology catalysed the transesterification of Jatropha curcas oil successfully. Face centered central composite design (FCCCD) under response surface methodology (RSM) was used to get the optimal conditions of 3% (w/w) enzyme loading, 4h reaction time and 1:6 oil/ethanol ratio to achieve the highest conversion of free fatty acid and glycerides into biodiesel (93%). The reusability of CLEA-lipase was tested and after seven cycles, the conversion percentage reduced to 58%. The results revealed that CLEA lipase from CPH is a potential catalyst for biodiesel production.

  4. High temperature co-treatment of bottom ash and stabilized fly ashes from waste incineration

    DEFF Research Database (Denmark)

    Sørensen, Mette Abildgaard; Mogensen, E.P.B.; Lundtorp, Kasper

    2001-01-01

    Bottom ashes from two Danish municipal solid waste incineration plants were heated at 900 degreesC with iron oxide stabilized air pollution control residues at actual mass flow ratios (9:1), simulating a treating method for the residues. The two residues were cotreated, producing one combined...

  5. Potential of phosphorus recovery from sewage sludge and manure ash by thermochemical treatment.

    Science.gov (United States)

    Havukainen, Jouni; Nguyen, Mai Thanh; Hermann, Ludwig; Horttanainen, Mika; Mikkilä, Mirja; Deviatkin, Ivan; Linnanen, Lassi

    2016-03-01

    All life forms require phosphorus (P), which has no substitute in food production. The risk of phosphorus loss from soil and limited P rock reserves has led to the development of recycling P from industrial residues. This study investigates the potential of phosphorus recovery from sewage sludge and manure ash by thermochemical treatment (ASH DEC) in Finland. An ASH DEC plant could receive 46-76 kt/a of sewage sludge ash to produce 51-85 kt/a of a P-rich product with a P2O5 content of 13-18%, while 320-750 kt/a of manure ash could be supplied to produce 350-830 kt/a of a P-rich product with a P content of 4-5%. The P2O5 potential in the total P-rich product from the ASH DEC process using sewage sludge and manure ash is estimated to be 25-47 kt/a, which is significantly more than the P fertilizer demand in Finland's agricultural industries. The energy efficiency of integrated incineration and the ASH DEC process is more dependent on the total solid content and the subsequent need for mechanical dewatering and thermal drying than on the energy required by the ASH DEC process. According to the results of this study, the treated sewage sludge and manure ash using the ASH DEC process represent significant potential phosphorus sources for P fertilizer production.

  6. 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

    The chemical effects of silicate ash ejected by explosive volcanic eruptions on environmental systems are fundamentally mediated by ash particle surfaces. Ash surfaces are a composite product of magmatic properties and fragmentation mechanisms, as well as in-plume and atmospheric alteration processes acting upon those surfaces during and after the eruption. Recent attention has focused on the capacity of alteration processes to shape ash surfaces; most notably, several studies have utilised X-ray photoelectron spectroscopy (XPS), a technique probing the elemental composition and coordination state of atoms within the top 10 nm of ash surfaces, to identify patterns of elemental depletions and enrichments relative to bulk ash chemical composition. Under the presumption of surface and bulk equivalence, any disparities have been previously attributed to surface alteration processes, but the ubiquity of some depletions (e.g., Ca, Fe) across multiple ash studies, irrespective of eruptive origin, could suggest these to be features of the surface produced at the instant of magma fragmentation. To investigate this possibility further, we conducted rapid decompression experiments at different pressure conditions and at ambient and magmatic temperature on porous andesitic rocks. These experiments produced fragmented ash material untouched by secondary alteration, which were compared to particles produced by crushing of large clasts from the same experiments. We investigated a restricted size fraction (63-90 μm) from both fragmented and crushed materials, determining bulk chemistry and mineralogy via XRF, SEM-BSE and EPMA, and investigated the chemical composition of the ash surface by XPS. Analyses suggest that fragmentation under experimental conditions partitioned a greater fraction of plagioclase-rich particles into the selected size fraction, relative to particles produced by crushing. Trends in surface chemical composition in fragmented and crushed particles mirror that

  7. 干式排渣系统网条生产设备的研制%Development of Steel Net Strip Producing Equipment in Dry Bottom Ash Handling System

    Institute of Scientific and Technical Information of China (English)

    张培林

    2015-01-01

    Stainless steel net strip is the key components of dry bottom ash handling system,usually be cold manufactured by the stainless steel wire of the greater tensile strength,the process is complex,the forming is difficult and in the same time,there is not the professional production equipment interiorly for manufacturing such products.We developed the net strip winding machine for the engineering demand of dry bottom ash handling system.The net strip product,manufactured through this equipment,has been well validated in engineering practice,this equipment fill a domestic gap in the field,with the great value of development and application.%网条是干式排渣系统的关键零部件,通常采用抗拉强度较大的不锈钢丝冷加工而成,其加工工艺复杂,成形难度大,而目前国内尚无此类产品的专业生产设备.针对干式排渣系统的工程需求,研制了网条绕制机.该设备绕制的网条产品在工程实践中得到了很好的验证,填补了该领域的国内空白,具有广泛的应用与开发价值.

  8. Optimizing and Characterizing Geopolymers from Ternary Blend of Philippine Coal Fly Ash, Coal Bottom Ash and Rice Hull Ash

    Directory of Open Access Journals (Sweden)

    Martin Ernesto Kalaw

    2016-07-01

    Full Text Available Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC, which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerged as a sustainable option vis-à-vis OPC for three reasons: (1 their technical properties are comparable if not better; (2 they can be produced from industrial wastes; and (3 within reasonable constraints, their production requires less energy and emits significantly less CO2. In the Philippines, the use of coal ash, as the alumina- and silica- rich geopolymer precursor, is being considered as one of the options for sustainable management of coal ash generation from coal-fired power plants. However, most geopolymer mixes (and the prevalent blended OPC use only coal fly ash. The coal bottom ash, having very few applications, remains relegated to dumpsites. Rice hull ash, from biomass-fired plants, is another silica-rich geopolymer precursor material from another significantly produced waste in the country with only minimal utilization. In this study, geopolymer samples were formed from the mixture of coal ash, using both coal fly ash (CFA and coal bottom ash (CBA, and rice hull ash (RHA. The raw materials used for the geopolymerization process were characterized using X-ray fluorescence spectroscopy (XRF for elemental and X-ray diffraction (XRD for mineralogical composition. The raw materials’ thermal stability and loss on ignition (LOI were determined using thermogravimetric analysis (TGA and reactivity via dissolution tests and inductively-coupled plasma mass spectrometry (ICP analysis. The mechanical, thermal and microstructural properties of the geopolymers formed were analyzed using compression tests, Fourier transform infra-red spectroscopy (FTIR

  9. The impact of co-firing sunflower husk pellets with coal in a boiler on the chemical composition of flue gas

    Directory of Open Access Journals (Sweden)

    Zajemska Monika

    2017-01-01

    The calculations showed that the most important influence on the composition of the flue gas from the co-firing process of coal with sunflower husk has a composition of biomass. It should be emphasized that the results of computer simulations obtained by the authors have an useful aspect and can be applied in practice, especially to the analysis of the mechanism of chloride corrosion which is possible to occur due to the chlorine content in the biomass. They may also be useful for evaluating the unburned hydrocarbons produced by combustion of rich mixtures (λ < 1.0.

  10. Co-combustion of coal and sewage sludge: chemical and ecotoxicological properties of ashes.

    Science.gov (United States)

    Barbosa, Rui; Lapa, Nuno; Boavida, Dulce; Lopes, Helena; Gulyurtlu, Ibrahim; Mendes, Benilde

    2009-10-30

    The co-combustion of sewage sludge (SS) and coal is widely used for the treatment and thermal valorization of SS produced in wastewater treatment plants. The chemical and ecotoxicological properties of the ashes produced in this thermal treatment have not been fully studied. Two combustion tests were performed in a fluidized bed combustor. Colombian coal was used as fuel in test A. A blend (1+1) of this coal and a stabilized SS (Biogran) was used in a second test B. Samples of the bottom and fly ashes trapped in two sequential cyclones were collected. The characterization of the ashes was focused on two main aspects: (1) the bulk content of a set of metals and (2) the characterization of eluates produced according to the European Standard leaching test EN 12457-2. The eluates were submitted to an ecotoxicological characterization for two bio-indicators. In what concerns the bulk content of ashes, both combustion tests have produced ashes with different compositions. The ashes formed during the co-combustion test have shown higher concentrations of metals, namely Cr, Cu, Ni, Pb, Zn and Fe for all ashes. The leaching test has shown low mobility of these elements from the by-products produced during the combustion and co-combustion tests. Cr and Cr(VI) were mainly detected in the eluates of the 1st cyclone ashes produced in both combustion tests and in the 2nd cyclone ashes produced in the co-combustion test. Considering the ecotoxicity assays, the eluates of bottom and fly ashes for both combustion and co-combustion tests have shown low ecotoxic levels. The micro-crustacean Daphnia magna was generally more sensitive than the bacterium Vibrio fischeri. CEMWE criterion has allowed to classify the bottom ashes for both combustion and co-combustion tests as non-toxic residues and the fly ashes collected in both cyclones as toxic.

  11. Combined subcritical water and enzymatic hydrolysis for reducing sugar production from coconut husk

    Science.gov (United States)

    Muharja, Maktum; Junianti, Fitri; Nurtono, Tantular; Widjaja, Arief

    2017-05-01

    Coconut husk wastes are abundantly available in Indonesia. It has a potential to be used into alternative renewable energy sources such as hydrogen using enzymatic hydrolysis followed by a fermentation process. Unfortunately, enzymatic hydrolysis is hampered by the complex structure of lignocellulose, so the cellulose component is hard to degrade. In this study, Combined Subcritical Water (SCW) and enzymatic hydrolysis are applied to enhance fermentable, thereby reducing production of sugar from coconut husk. There were two steps in this study, the first step was coconut husk pretreated by SCW in batch reactor at 80 bar and 150-200°C for 60 minutes reaction time. Secondly, solid fraction from the results of SCW was hydrolyzed using the mixture of pure cellulose and xylanase enzymes. Analysis was conducted on untreated and SCW-treated by gravimetric assay, liquid fraction after SCW and solid fraction after enzymatic hydrolysis using DNS assay. The maximum yield of reducing sugar (including xylose, arabinose glucose, galactose, mannose) was 1.254 gr per 6 gr raw material, representing 53.95% of total sugar in coconut husk biomass which was obtained at 150°C 80 bar for 60 minutes reaction time of SCW-treated and 6 hour of enzymatic hydrolysis using mixture of pure cellulose and xylanase enzymes (18.6 U /gram of coconut husk).

  12. Two new isoxazolines from the husks of Xanthoceras sorbifolia Bunge.

    Science.gov (United States)

    Ge, Hui-Qi; Wan, Guo-Sheng; Wang, Da; Wu, Ji-Ming; Sun, Bo-Hang; Wu, Li-Jun; Gao, Hui-Yuan

    2016-08-01

    Two new isoxazoline compounds, 1-oxa-2-azaspiro[4.5]dec-2-ene-8β-ol (1) and 1-oxa-2-azaspiro[4.5]dec-2-ene-8α-ol (2), were isolated from the husks of fruits of Xanthoceras sorbifolia Bunge and their structures were determined by spectroscopic analyses, including X-ray crystallography, HRESI-MS, UV, IR, and 1D and 2D NMR (HSQC, HMBC, NOESY) methods. Neither compound showed significant inhibitory effects on butyrylcholinesterase (BuchE) and acetylcholinesterase (AChE), nor the selected tumor cells growth. Based on an online activity prediction program (PASS ONLINE), the structures with isoxazoline skeletons were found to show potential anti-asthmatic (AM) and anti-anaphylaxis (AP) activities; moreover, compounds 1 and 2 were predicted to possess high affinities for many enzymes involved in AM and AP according to the RCSB Protein Data Bank. High-affinity binding to phosphodiesterase IV (PDE-4), an important inflammatory modulator in asthma, was demonstrated experimentally, beside that, the predicted structures based on compounds 1 and 2 were analyzed for PDE-4 interactions using the molecular docking methodology of Discovery Studio 3.0 (DS 3.0). The predicted structure 2A-6 exhibited much higher affinity and stability of PDE-4 binding than the clinical PDE-4 inhibitor rolipram.

  13. Catalytic pyrolysis of waste rice husk over mesoporous materials

    Science.gov (United States)

    Jeon, Mi-Jin; Kim, Seung-Soo; Jeon, Jong-Ki; Park, Sung Hoon; Kim, Ji Man; Sohn, Jung Min; Lee, See-Hoon; Park, Young-Kwon

    2012-01-01

    Catalytic fast pyrolysis of waste rice husk was carried out using pyrolysis-gas chromatography/mass spectrometry [Py-GC/MS]. Meso-MFI zeolite [Meso-MFI] was used as the catalyst. In addition, a 0.5-wt.% platinum [Pt] was ion-exchanged into Meso-MFI to examine the effect of Pt addition. Using a catalytic upgrading method, the activities of the catalysts were evaluated in terms of product composition and deoxygenation. The structure and acid site characteristics of the catalysts were analyzed by Brunauer-Emmett-Teller surface area measurement and NH3 temperature-programmed desorption analysis. Catalytic upgrading reduced the amount of oxygenates in the product vapor due to the cracking reaction of the catalysts. Levoglucosan, a polymeric oxygenate species, was completely decomposed without being detected. While the amount of heavy phenols was reduced by catalytic upgrading, the amount of light phenols was increased because of the catalytic cracking of heavy phenols into light phenols and aromatics. The amount of aromatics increased remarkably as a result of catalytic upgrading, which is attributed to the strong Brönsted acid sites and the shape selectivity of the Meso-MFI catalyst. The addition of Pt made the Meso-MFI catalyst even more active in deoxygenation and in the production of aromatics.

  14. Antimalarial Activity of Cocos nucifera Husk Fibre: Further Studies

    Directory of Open Access Journals (Sweden)

    J. O. Adebayo

    2013-01-01

    Full Text Available In this study, the antimalarial and toxicity potentials of husk fibre extracts of five Nigerian varieties of Cocos nucifera were evaluated in vitro. The only active extract fraction, West African Tall (WAT ethyl acetate extract fraction, was then evaluated for its phytochemical constituents, antimalarial and toxicity potentials at varying doses (31.25–500 mg/kg body weight using various organ function indices. The results revealed that WAT ethyl acetate extract fraction (WATEAEF contained alkaloids, tannins, and flavonoids and was active against Plasmodium falciparum W2 strain maintained in continuous culture, with a selectivity index of 30.3. The same extract fraction was active in vivo against Plasmodium berghei NK65, causing more than 50% reduction in parasitaemia on days 4 and 6 after inoculation at various doses administered. WATEAEF did not significantly alter (P>0.05 function indices of the liver and cardiovascular system at all doses administered but significantly increased (P<0.05 plasma creatinine concentration at 250 and 500 mg/Kg body weight compared to controls. The results of this study suggest that WATEAEF possesses antimalarial activity and may not adversely affect normal liver function nor predispose subjects to cardiovascular diseases but may impair normal kidney function at higher doses. Further studies are underway to isolate the active principles.

  15. Pyrolysis kinetics of Melon (Citrullus colocynthis L.) seed husk

    CERN Document Server

    Nyakuma, Bemgba Bevan

    2015-01-01

    This study is aimed at investigating the thermochemical fuel characteristics and kinetic decomposition of melon seed husks (MSH) under inert (pyrolysis) conditions. The calorific value, elemental composition, proximate analyses and thermal kinetics of MSH was examined. The kinetic parameters; activation energy E and frequency factor A for MSH decomposition under pyrolysis conditions were determined using the Kissinger and isoconversional Flynn-Wall-Ozawa (FWO) methods. The values of E for MSH ranged from 146.81 to 296 kJ/mol at degrees of conversion {\\alpha} = 0.15 to 0.60 for FWO. The decomposition of MSH process was fastest at {\\alpha} = 0.15 and slowest at {\\alpha} = 0.60 with average E and A values of 192.96 kJ/mol and 2.86 x 1026 min-1, respectively at correlation values of 0.9847. The kinetic values of MSH using the Kissinger method are E = 161.26 kJ/mol and frequency factor, A = 2.08 x 1010 min-1 with the correlation value, R2 = 0.9958. The results indicate that MSH possesses important characteristics ...

  16. The root system of the husk tomato (Physalis ixocarpa Brot.

    Directory of Open Access Journals (Sweden)

    Juan Mulato Brito

    2013-12-01

    Full Text Available The husk tomato (Physalis ixocarpa Brot. is widely cultivated in central Mexico, and may be grown in countries with a temperate climate. The experiment was set up during the dry period of the year (average weekly temperature 17-22°C in the State of Morelos, Mexico, using the cv. 'Rendidora' in loamy clay soil and furrow irrigation. The roots were investigated by the pinboard method modified by Garcia Blancas and Grajeda Gómez (in print, partly adapted by us for quantitative estimation of root systems. Two plants were investigated every second week. They had a well developed tap root. Most of their lateral roots were found in the superficial soil layer, 0-20 cm. The root dry mass was also concentrated near the central axis of the plant. The majority of root apices were, however, found in the soil cylinders 10-40 em from the central axis. During the senescence of the aerial part (14th week after emergence the root system lost a large part of its small roots. The modification of the pinboard method, by Garcia Blancas and Grajeda Gómez (in print permited us investigating the root systems with very simple tools, in situ.

  17. A Simple Method of Obtaining Spherical Nanosilica from Rice Husk

    Directory of Open Access Journals (Sweden)

    Mohammed Noushad

    2012-01-01

    Full Text Available This paper describes the synthesis of nanosilica from rice husk. Synthesis was done by precipitation using different acids, namely, orthophosphoric acid and nitric acid which yielded nanosilica. The effect of different acids and different solvents (polar and non-polar on the size and degree of agglomeration of the silica particles were studied. When precipitation was done without the use of solvents, the silica particles  obtained were non-spherical in shape, whereas, when precipitation was done using polar solvents (ethanol or 2-propanol, the silica particles were spherical. The use of non-polar solvents (toluene and diethyl ether resulted in silica particles that were irregular in shape and in the case of orthophosphoric acid, a high degree of agglomeration was also noted. The degree of agglomeration was less when orthophosphoric acid was used with polar solvents as compared to nitric acid in conjunction with polar solvents. As regards the size, it ranged from approximately 70nm to 400nm when either acid was used in conjunction with polar solvents. When non-polar solvents were used, the silica particles were irregular in shape and the particle size was not estimated.

  18. Hydrothermal synthesis of zeolites from coal fly ash

    OpenAIRE

    Kotova, OB; Shabalin, Igor L; Shushkov, DA; Kocheva, LS

    2015-01-01

    The fly ash, from the combustion of coal to produce energy and heat, is an industrial waste, in which large accumulations represent a serious environmental threat. To reduce the environmental burden and improve the economic benefits of energy production, the science and industry focus on the transformation of coal combustion byproducts into new functional materials. The fly ash was studied by modern analytical methods. As a result of the hydrothermal reaction, several types of zeolites were s...

  19. Mswi bottom ash for upgrading of biogas and landfill gas.

    Science.gov (United States)

    Mostbauer, P; Lenz, S; Lechner, P

    2008-07-01

    A new upgrading process for biogas and landfill gas (LFG) has been designed recently by the authors' institute. The process uses the alkalinity of the fine fraction of bottom ash from municipal solid waste incineration (MSWI) for sorbing CO2 and H2S. Results from process development and optimisation are presented in this paper. It is expected that nearly pure CH4 can be produced for substitution of fossil fuels. Simultaneously, the leachability of MSWI bottom ash is clearly reduced.

  20. Crowdsourcing genomic analyses of ash and ash dieback – power to the people

    Directory of Open Access Journals (Sweden)

    MacLean Dan

    2013-02-01

    Full Text Available Abstract Ash dieback is a devastating fungal disease of ash trees that has swept across Europe and recently reached the UK. This emergent pathogen has received little study in the past and its effect threatens to overwhelm the ash population. In response to this we have produced some initial genomics datasets and taken the unusual step of releasing them to the scientific community for analysis without first performing our own. In this manner we hope to ‘crowdsource’ analyses and bring the expertise of the community to bear on this problem as quickly as possible. Our data has been released through our website at oadb.tsl.ac.uk and a public GitHub repository.

  1. 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.

  2. 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....

  3. Bench-scale synthesis of zeolite A from subbituminous coal ashes with high crystalline silica content

    Energy Technology Data Exchange (ETDEWEB)

    Chareonpanich, M.; Jullaphan, O.; Tang, C. [Kasetsart University, Bangkok (Thailand). Dept. of Chemical Engineering

    2011-01-15

    In this present work, fly ash and bottom ash with high crystalline silica content were obtained from the coal-fired boilers within the paper industries in Thailand. These coal ashes were used as the basic raw materials for synthetic zeolite production. The crystal type and crystallinity, specific surface area and pore size, and textural properties of zeolite products were characterized by using X-ray diffraction spectroscopy (XRD), N{sub 2} sorption analysis, and Scanning Electron Microscopy (SEM), respectively. It was found that sodalite octahydrate was selectively formed via the direct conventional (one-step) synthesis, whereas through a two-step, sodium silicate preparation and consecutive zeolite A synthesis process, 94 and 72 wt.% zeolite A products could be produced from the fly ash and bottom ash, respectively. The cation-exchange capacity (CEC) of fly ash and bottom ash-derived zeolite A products were closely similar to that of the commercial grade zeolite A.

  4. Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

    Energy Technology Data Exchange (ETDEWEB)

    V.K. Konovalov; O.V. Yashkin; V.V. Ermakov [Kashira GRES, Moscow (Russian Federation)

    2008-03-15

    A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered.

  5. Electrical properties of volcanic ash samples from Eyjafjallaj\\"okull and Gr\\'imsv\\"otn

    CERN Document Server

    Houghton, I M; Nicoll, K A

    2012-01-01

    Volcanic ash is known to charge electrically, producing some of the most spectacular displays of lightning in nature. Here we investigate the electrical characteristics of ash from two different Icelandic volcanoes - Eyjafjallaj\\"okull in 2010 and Gr\\'imsv\\"otn in 2011. Laboratory tests investigated the charge transferred to a conducting plate due to fall of volcanic ash through an insulating cylinder. Ash from the Eyjafjallaj\\"okull eruption was found to charge slightly positively, whilst Gr\\'imsv\\"otn ash was substantially negatively charged. Measurement of the volumetric ratio of particle diameters showed the Eyjafjallaj\\"okull ash to have a bimodal distribution, and the Gr\\'imsv\\"otn ash a monomodal distribution. Previous experiments with single-material particle systems show that smaller particles charge negatively and larger ones positively. Since charge is carried by individual particles, the charging is likely to be dominated by the number size distribution, therefore the large negative charge of the ...

  6. Production of ceramics from coal fly ash

    Directory of Open Access Journals (Sweden)

    Angjusheva Biljana

    2012-01-01

    Full Text Available Dense ceramics are produced from fly ash from REK Bitola, Republic of Macedonia. Four types of fly ash from electro filters and one from the collected zone with particles < 0.063 mm were the subject of this research. Consolidation was achieved by pressing (P= 133 MPa and sintering (950, 1000, 1050 and 11000C and heating rates of 3 and 100/min. Densification was realized by liquid phase sintering and solid state reaction where diopside [Ca(Mg,Al(Si,Al2O6] was formed. Ceramics with optimal properties (porosity 2.96±0.5%, bending strength - 47.01±2 MPa, compressive strength - 170 ±5 MPa was produced at 1100ºC using the heating rate of 10ºC/min.

  7. 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.

  8. Using cultural-historical activity theory to analyze social service practices evolving from the Norwegian HUSK projects.

    Science.gov (United States)

    Foot, Kirsten

    2015-01-01

    The HUSK projects catalyzed innovation in the practices of providing social services that could yield useful insights both within and outside of Norway if analyzed in these two ways: (a) retrospective analysis of the development of individual HUSK projects in light of their cultural-historical contexts, and (b) comparative analysis of the efforts to advance multi-sector collaboration in some of the HUSK projects. Such analyses require a practice-based research approach that takes into account culture and history. In this article the author explains how cultural-historical activity theory provides such an approach, illustrated via several HUSK cases. The author suggests five questions for future analyses of the HUSK projects and argues that insights gleaned from such analyses could contribute significantly to research on-and the provision of-social services.

  9. Evaluation of untreated coffee husks as potential biosorbents for treatment of dye contaminated waters.

    Science.gov (United States)

    Oliveira, Leandro S; Franca, Adriana S; Alves, Thiago M; Rocha, Sônia D F

    2008-07-15

    The objective of this work was to propose an alternative use for coffee husks (CH), a coffee processing residue, as untreated sorbents for the removal of methylene blue (MB) from aqueous solutions. The effects of solution temperature, pH, biosorbent dosage and contact time on MB removal were investigated. The experimental adsorption equilibrium data were fitted to both Langmuir and Freundlich adsorption models. The biosorption kinetics was determined by fitting first and second-order kinetic models to the experimental data, with the second-order model providing the best description of MB adsorption onto coffee husks. pH variations did not present a significant effect on MB removal. Evaluation of thermodynamics parameters indicated that the adsorption is spontaneous and endothermic. The experimental data obtained in the present study demonstrated coffee husks to be suitable candidates for use as biosorbents in the removal of cationic dyes.

  10. Thermal decomposition analysis of coal-waste sludge and coal-sunflower seed husk blends

    Institute of Scientific and Technical Information of China (English)

    WANG Shu-yan; LI Xiao-qi; LIU Wen-tie; SONG Cheng-yi; WANG Chun-sheng; DONG Qun

    2010-01-01

    The thermal decomposition analysis of coal-pharmaceutical waste sludge,coal-sewage waste sludge blends and coal-sunflower seed husk blends are studied by TG dynamic runs at the heating rate of 20 ℃/min within the temperature range of 25 ℃-900℃.The effect of different kinetic models on the determination of kinetic parameters of thermal decompesition has been investigated.Results show that for coal-pharmaceutical sludge blend,coal-sewage sludge blend and coal-sunflower seed husk blend the optimal model functions are the three-dimensional diffusion reaction,2-dimensional and 3-diemensional nucleation and growth reactions,respectively.The Arrhenius kinetic parameters of the pre-exponential factor and activation energy of blends,as well waste sludge and sunflower seed husk only are proposed.

  11. Enhancing nutrient recovery and compost maturity of coconut husk by vermicomposting technology.

    Science.gov (United States)

    Swarnam, T P; Velmurugan, A; Pandey, Sanjay Kumar; Dam Roy, S

    2016-05-01

    Vermicompost was prepared by five different treatments from relatively resistant coconut husk mixed with either pig slurry or poultry manure. The recovery of vermicompost varied from 35% to 43% and it resulted in significant increase in pH, microbial biomass carbon, macro and micro nutrients concentration. Among the treatments highest relative N (1.6) and K (1.3) recovery were observed for 20% feedstock substitution by pig slurry while poultry manure substitution recorded highest P recovery (2.4). Compost maturity parameters significantly differed and well correlated. The characteristics of different treatments established the maturity indices as C/N 15-20; Cw1.5 and HI>15.0. The manurial value of the coconut husk compost was improved by feedstock substitution with pig slurry (80:20). The results revealed the technical feasibility of converting coconut husk into valuable compost by feedstock substitution with pig slurry.

  12. A study on biocomposite from local balinese areca catechu l. husk fibers as reinforced material

    Science.gov (United States)

    Kencanawati, C. I. P. K.; Suardana, N. P. G.; Sugita, I. K. G.; Suyasa, I. W. B.

    2017-05-01

    Untapped areca catechu l. husk fibers optimally can cause pollution to the environment. Therefore it is necessary to learn the characteristics of local balinese areca catechu l. husk fibers, such as physical, chemical, morphological, and mechanical. AHF testing the tensile strength with a single pull fiber test in accordance with ASTM D 3379 in the amount of 146-152 MPa. While the observation of the physical properties, of local balinese areca catechu l. husk fibers have a diameter and length variations of each 250-540 μm and 9.24 to 55.20 mm, with an aspect ratio of between 31.43 to 102.22, density ranges between 0:48 - 0.74 kg / cm3, absorption lower water (90-150%) when compared to AHF grows in other areas. From this study it appears that local Bali AHF can be used as reinforcement in composite replacement for synthetic fibers.

  13. MGT 401 ASH Course Tutorial / Tutorialoutlet

    OpenAIRE

    kennith

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   MGT 401 Week 1 Individual Assignment Strategic Management Process Paper (Ash) MGT 401 Week 1 Class Activity Week 1 (Ash) MGT 401 Week 1 DQ 1 (Ash) MGT 401 Week 1 DQ 2 (Ash) MGT 401 Week 2 Learning Team Business Model Comparison Example (Ash) MGT 401 Week 2 DQ 1 (Ash) MGT 401 Week 2 DQ 2 (Ash) MGT 401 Week 2 Class Activity (Ash) MGT 401 Week 3 Individual Assignment Business Plan Evaluation (Ash) ...

  14. SYNTHESIS AND CHARATERISATION OF RICE HUSK SILICA BASED BOROSILICATE (B2SiO5 CERAMIC BY SOL-GEL ROUTES

    Directory of Open Access Journals (Sweden)

    Simon Sembiring

    2011-07-01

    Full Text Available In this research, borosilicate ceramics were produced from rice husk silica. Preparation of borosilicate ceramics was conducted by mixing boron oxide sol from borax with silica sol extracted from rice husk. The boron oxide was produced by hydrolysis of borax using H2SO4 5%. The samples were synthesized with different compositions, with the ratios of silica to boron oxide are 8:1, 8:2, 8:3 and 8:4. The samples were sintered at 900 °C. Functional groups were examined using FTIR spectroscopic technique. Structural and microstructural characteristics were examined by XRD and SEM, respectively. The chemical resistance of borosilicate is evaluated by gravimetric method using H2SO4, HCl, NaOH and KOH. The FTIR study revealed that the main functional groups are Si-O-Si, B-O-B, and B-O-Si. The x-ray diffraction (XRD study revealed that the main crystalline phases are borosilicate (B2SiO5 and boron oxide (B2O3. SEM investigations clearly demonstrated that the smaller particle size was found with increasing in boron oxide concentration. From the chemical resistance test carried out, it was obtained that the produced borosilicate possessed high resistance to acids and alkalis.

  15. Recycled High-Density Polyethylene and Rice Husk as a Wetted Pad in Evaporative Cooling System

    Directory of Open Access Journals (Sweden)

    Nitipong Soponpongpipat

    2011-01-01

    Full Text Available Problem statement: The low cost and easy-to-find materials, for being used as wetted pad of evaporative cooling system, are necessary for agriculture. This study, thus, studied the evaporative cooling efficiency and pressure drop of recycled High-Density Polyethylene (HDPE and rice husk as a wetted pad in evaporative cooling system. Approach: The study was done by establishing the tested wetted pad with 25.4 and 50.8 mm of thickness. The velocity air flow through wetted pad was controlled at 1, 2 and 3 m sec−1 respectively. In addition, the dry bulb and wet bulb temperatures of inlet air were controlled at 30.1 ± 1.0°C and 23.2 ± 1.1°C, respectively. The commercial wetted pad was also tested in order to compare results with rice husk and recycled HDPE. Results: It was found that rice husk wetted pad gave the average saturation efficiency of 55.9 %, while HDPE gave the average saturation efficiency of 29.1%. However, the pressure drop across wetted pad of rice husk and recycled HDPE was significantly higher than that of commercial wetted pad. For the effect of air velocity on saturation efficiency and pressure drop, it was found that higher air velocity decreased saturation efficiency and increased pressure drop across wetted pad. Conclusion: Finally, the rice husk has a potential as wetted pad material. However, further study about optimum point between operation cost and materials cost of using rice husk wetted pad is needed.

  16. To fractionate municipal solid waste incineration bottom ash: Key for utilisation?

    Science.gov (United States)

    Sormunen, Laura Annika; Rantsi, Riina

    2015-11-01

    For the past decade, the Finnish waste sector has increasingly moved from the landfilling of municipal solid waste towards waste incineration. New challenges are faced with the growing amounts of municipal solid waste incineration bottom ash, which are mainly landfilled at the moment. Since this is not a sustainable or a profitable solution, finding different utilisation applications for the municipal solid waste incineration bottom ash is crucial. This study reports a comprehensive analysis of bottom ash properties from one waste incineration plant in Finland, which was first treated with a Dutch bottom ash recovery technique called advanced dry recovery. This novel process separates non-ferrous and ferrous metals from bottom ash, generating mineral fractions of different grain sizes (0-2 mm, 2-5 mm, 5-12 mm and 12-50 mm). The main aim of the study was to assess, whether the advanced bottom ash treatment technique, producing mineral fractions of different grain sizes and therefore properties, facilitates the utilisation of municipal solid waste incineration bottom ash in Finland. The results were encouraging; the bottom ash mineral fractions have favourable behaviour against the frost action, which is especially useful in the Finnish conditions. In addition, the leaching of most hazardous substances did not restrict the utilisation of bottom ash, especially for the larger fractions (>5 mm). Overall, this study has shown that the advanced bottom ash recovering technique can be one solution to increase the utilisation of bottom ash and furthermore decrease its landfilling in Finland.

  17. 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.

  18. The cumulative ash curve: a best tool to evaluate complete mill performance.

    Science.gov (United States)

    Sakhare, Suresh D; Inamdar, Aashitosh A

    2014-04-01

    Slick test is carried out by a flour miller to qualitatively segregate the flour from different streams in a roller flour mill. This test is done manually by pressing flour samples on tray using thin bladed paddle (the slick) and inspecting color or dress of the sample. However, the test is subjective and totally depends on human judgment. Cumulative ash curve relates to cumulative flour ash content and cumulative flour yield, which could help a flour miller to be more precise while selecting flour streams for different needs. In this study, cleaning and conditioning of wheat was carried out in the pilot plant of International School of Milling Technology (ISMT). Further, roller flour milling of wheat was done. Flour from different streams (four breaks, five reductions) was collected. Each flour stream was analyzed for ash content using standard AACC methods. The analytical values of ash content were used to plot the cumulative ash curve. It was found that ash content increased in the break passages from first to last break, with exception of first break (ash content 0.71%). An increase in percentage of ash was observed in the reduction passages (C1 to C5), however, C3 ash (0.76%) was slightly higher than that of C4 (0.65%). Higher yield of flour with minimum ash content was obtained from the front reduction passages C1 and C2; whereas, the break passages and the tail end reduction passages produce less flour with higher ash content.

  19. Development of the husk tomato plant (Physalis ixocarpa Brot.. III. Growth analysis

    Directory of Open Access Journals (Sweden)

    Francisco Cartujano-Escobar

    2014-01-01

    Full Text Available Growth analysis of husk tomato plants cv. Rendidora was done applying classical methods. Quantities such as the Relative Growth Rate, Leaf Area Ratio, Unit Leaf Rate and others were calculated in order to describe the changes which occur in the Physalis ixocarpa plant during its development from emergence to death. The mentioned quantities comported differently in the four periods of the life of husk tomato, providing a good insight into the changing direction and intensity of the main physiological processes and their mutual balance. It is believed that such recognition of the properties of a plant may help breeders.

  20. Coffee husk composting: An investigation of the process using molecular and non-molecular tools

    OpenAIRE

    Shemekite, Fekadu; Gómez-Brandón, María; Franke-Whittle, Ingrid H.; Praehauser, Barbara; Insam, Heribert; Assefa, Fassil

    2014-01-01

    Various parameters were measured during a 90-day composting process of coffee husk with cow dung (Pile 1), with fruit/vegetable wastes (Pile 2) and coffee husk alone (Pile 3). Samples were collected on days 0, 32 and 90 for chemical and microbiological analyses. C/N ratios of Piles 1 and 2 decreased significantly over the 90 days. The highest bacterial counts at the start of the process and highest actinobacterial counts at the end of the process (Piles 1 and 2) indicated microbial succession...

  1. Dielectric properties of fly ash

    Indian Academy of Sciences (India)

    S C Raghavendra; R L Raibagkar; A B Kulkarni

    2002-02-01

    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 is because of orientation polarization and tight binding force between the ions or atoms in the fly ash. The sample of fly ash is of great scientific and technological interest because of its high value of dielectric constant (104).

  2. Ash dispersal dynamics: state of the art and perspectives

    Science.gov (United States)

    Sulpizio, R.

    2013-05-01

    Volcanic ash, during dispersal and deposition, is among the major hazards from explosive eruptions. Volcanic ash fallout can disrupt communities downwind, interrupt surface transportation networks and lead to closure of airports. Airborne ash seriously threatens modern jet aircraft in flight. In several documented cases, encounters between aircraft and volcanic clouds have resulted in engine flameout and near crashes, so there is a need to accurately predict the trajectory of volcanic ash clouds in order to improve aviation safety and reduce economic losses. The ash clouds affect aviation even in distal regions, as demonstrated by several eruptions with far-range dispersal. Recent examples include Crater Peak 1992, Tungurahua 1999-2001, Mount Cleveland 2001, Chaitén 2008, Eyjafjallajökull 2010, Grimsvötn 2011, and Cordón-Caulle 2011. Amongst these, the April-May 2010 eruption of Eyjafjallajökull in Iceland provoked the largest civil aviation breakdown. Accumulation of tephra can produce roof collapse, interruption of lifelines (roads, railways, etc.), disruption to airport operations, and damage to communications and electrical power lines. Deposition of ash decreases soil permeability, increases surface runoff, and promotes floods. Ash leaching can result in the pollution of water resources, damage to agriculture, pastures, and livestock, impinge on aquatic ecosystems, and alteration of the geochemical environment on the seafloor. Despite the potential big impact, the dispersal dynamics of volcanic ash is still an unsolved problem for volcanologists, which claims for fiture high level research. Here, a critical overview about models (field, experimental and numerical) for inversion of field data to gain insights on physics of dispersal of volcanic ash is proposed. A special focus is devoted to some physical parameters that are far from a satisfactory inversion (e.g. reconstruction of total grain size distribution), and clues for future research are suggested.

  3. Preliminary Strength Measurements of High Temperature Ash Filter Deposits

    Energy Technology Data Exchange (ETDEWEB)

    Kang, B.S.; Johnson, E.K.; Mallela, R.; Barberio, J.F. [West Virginia Univ., Morgantown, WV (United States). Dept. of Mechanical and Aerospace Engineering

    1996-12-31

    The objective of this study is to develop and evaluate preliminary strength measurement techniques for high temperature candle filter ash deposits. The efficient performance of a high temperature gas filtering system is essential for many of the new thermal cycles being proposed for power plants of the future. These new cycles hold the promise of higher thermal efficiency and lower emissions of pollutants. Many of these cycles involve the combustion or gasification of coal to produce high temperature gases to eventually be used in gas turbines. These high temperature gases must be relatively free of particulates. Today, the candle filter appears to be the leading candidate for high temperature particulate removal. The performance of a candle filter depends on the ash deposits shattering into relatively large particles during the pulse cleaning (back flushing) of the filters. These relatively large particles fall into the ash hopper and are removed from the system. Therefore, these 1247 particles must be sufficiently large so that they will not be re-entrained by the gas flow. The shattering process is dictated by the strength characteristics of the ash deposits. Consequently, the objective of this research is to develop measurements for the desired strength characteristics of the ash deposits. Experimental procedures were developed to measure Young`s modulus of the ash deposit at room temperature and the failure tensile strain of ash deposits from room temperature to elevated temperatures. Preliminary data has been obtained for both soft and hard ash deposits. The qualifier ``preliminary`` is used to indicate that these measurements are a first for this material, and consequently, the measurement techniques are not perfected. In addition, the ash deposits tested are not necessarily uniform and further tests are needed in order to obtain meaningful average data.

  4. Chemical characterization and oxidative potential of particles emitted from open burning of cereal straws and rice husk under flaming and smoldering conditions

    Science.gov (United States)

    Fushimi, Akihiro; Saitoh, Katsumi; Hayashi, Kentaro; Ono, Keisuke; Fujitani, Yuji; Villalobos, Ana M.; Shelton, Brandon R.; Takami, Akinori; Tanabe, Kiyoshi; Schauer, James J.

    2017-08-01

    Open burning of crop residue is a major source of atmospheric fine particle emissions. We burned crop residues (rice straws, barley straws, wheat straws, and rice husks produced in Japan) in an outdoor chamber and measured particle mass, composition (elemental carbon: EC, organic carbon: OC, ions, elements, and organic species), and oxidative potential in the exhausts. The fine particulate emission factors from the literature were within the range of our values for rice straws but were 1.4-1.9 and 0.34-0.44 times higher than our measured values for barley straw and wheat straw, respectively. For rice husks and wheat straws, which typically lead to combustion conditions that are relatively mild, the EC content of the particles was less than 5%. Levoglucosan seems more suitable as a biomass burning marker than K+, since levoglucosan/OC ratios were more stable than K+/particulate mass ratios among crop species. Stigmasterol and β-sitosterol could also be used as markers of biomass burning with levoglucosan or instead of levoglucosan. Correlation analysis between chemical composition and combustion condition suggests that hot or flaming combustions enhance EC, K+, Cl- and polycyclic aromatic hydrocarbons emissions, while low-temperature or smoldering combustions enhance levoglucosan and water-soluble organic carbon emissions. Oxidative potential, measured with macrophage-based reactive oxygen species (ROS) assay and dithiothreitol (DTT) assay, of open burning fine particles per particulate mass as well as fine particulate emission factors were the highest for wheat straws and second highest for rice husks and rice straws. Oxidative potential per particulate mass was in the lower range of vehicle exhaust and atmosphere. These results suggest that the contribution of open burning is relatively small to the oxidative potential of atmospheric particles. In addition, oxidative potential (both ROS and DTT activities) correlated well with water-insoluble organic species

  5. Physical, mechanical and thermal evaluation of material soil-cement-rice husk ash and its performance on monolithic wall

    OpenAIRE

    Ana Paula da Silva Milani

    2008-01-01

    Resumo: No Brasil existem sérios problemas ambientais no que se refere à constante geração de resíduos agroindustriais e a falta de tecnologias e materiais de construção energeticamente eficientes. Buscando um material alternativo de construção que minimize esta degradação ambiental e reduza os custos energéticos do produto final, no presente trabalho foram pesquisadas diferentes misturas de solo-cimento-cinza de casca de arroz, de forma a resgatar o uso da terra crua como elemento construtiv...

  6. Strength Properties of Fly Ash Based Geopolymer Concrete with Sea Sand

    OpenAIRE

    2016-01-01

    The production of every ton of cement contributes to production of one ton of CO2. With the development of infra activities, the power sector activities are also increasing. The coal based power plant produces huge quantity of fly ash, which creates its disposal problems. However to some extent, the fly ash is used as partial substitution to cement. The alkali activated fly ash concrete (Geopolymer Concrete) proposed by Devidovits, shows considerable promise for application in construction in...

  7. Influence of Bed Ash and Fly Ash Replacement in Mortars

    Directory of Open Access Journals (Sweden)

    S. L. Summoogum-Utchanah

    2015-03-01

    Full Text Available The study evaluates the influence of fly ash and bottom ash as partial cement substitutes in mortars by studying the particle size distribution, consistency, flow, fresh density, air content, compressive strength and flexural strength characteristics. The results revealed that fly ash and cement had relatively the same particle size distribution unlike bottom ash. In the fresh state, as the amount of pozzolans increased in the mixtures, the mortars showed an enhancement in workability, were susceptible to water loss by bleeding, and exhibited a decline in fresh density. The early strength gains of the fly ash samples were low but reached higher than the control after 28 days of curing. The flexural strength increased as the fly ash content rose to reach a maximum at 20 % replacement. However, the 2-day compressive strength of bottom ash samples was higher than the control but decreased after 28 days of curing while the flexural strength declined with addition of bottom ash except at 5 % substitution.

  8. Controls on the surface chemical reactivity of volcanic ash investigated with probe gases

    Science.gov (United States)

    Maters, Elena C.; Delmelle, Pierre; Rossi, Michel J.; Ayris, Paul M.; Bernard, Alain

    2016-09-01

    Increasing recognition that volcanic ash emissions can have significant impacts on the natural and human environment calls for a better understanding of ash chemical reactivity as mediated by its surface characteristics. However, previous studies of ash surface properties have relied on techniques that lack the sensitivity required to adequately investigate them. Here we characterise at the molecular monolayer scale the surfaces of ash erupted from Eyjafjallajökull, Tungurahua, Pinatubo and Chaitén volcanoes. Interrogation of the ash with four probe gases, trimethylamine (TMA; N(CH3)3), trifluoroacetic acid (TFA; CF3COOH), hydroxylamine (HA; NH2OH) and ozone (O3), reveals the abundances of acid-base and redox sites on ash surfaces. Measurements on aluminosilicate glass powders, as compositional proxies for the primary constituent of volcanic ash, are also conducted. We attribute the greater proportion of acidic and oxidised sites on ash relative to glass surfaces, evidenced by comparison of TMA/TFA and HA/O3 uptake ratios, in part to ash interaction with volcanic gases and condensates (e.g., H2O, SO2, H2SO4, HCl, HF) during the eruption. The strong influence of ash surface processing in the eruption plume and/or cloud is further supported by particular abundances of oxidised and reduced sites on the ash samples resulting from specific characteristics of their eruptions of origin. Intense interaction with water vapour may result in a higher fraction of oxidised sites on ash produced by phreatomagmatic than by magmatic activity. This study constitutes the first quantification of ash chemical properties at the molecular monolayer scale, and is an important step towards better understanding the factors that govern the role of ash as a chemical agent within atmospheric, terrestrial, aquatic or biotic systems.

  9. Reuse of Partially Sulphated CFBC Ash as an SO2 Sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yinghai; Jia, Lufei; Anthony, E.J. [CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario, K1A1M1 (Canada); Nobili, M.; Telesca, A. [Department of Environmental Engineering and Physics, University of Basilicata, Viale dell' Ateneo, Lucano 10, 85100 Potenza (Italy); Montagnaro, F. [Department of Chemistry, University of Naples ' Federico II' , Monte Sant' Angelo, 80126 Naples (Italy)

    2010-06-15

    Ashes produced from fluidized bed combustors (FBC) burning high-sulphur fuels often contain 20-30 % unreacted CaO because of the limestone added to remove SO2 in situ. This paper presents the results from experiments into reactivating partially sulphated FBC ash (both bed ash and fly ash) with liquid water, steam and sodium carbonate. The water- or steam-hydrated ashes were subsequently re-sulphated in a thermogravimetric analyzer (TGA) with simulated flue gas. The TGA results show that, while liquid water and steam successfully hydrate and reactivate the unreacted CaO in the bed ash, the treated ashes sulphated to widely different extents. Attempts to reactivate fly ash with hydration failed, although fly ash by itself is extremely reactive. A pilot-scale mini-circulating FBC (CFBC) was also used to evaluate the results of reactivation on the bed ash by hydrating with liquid water and admixtures of inorganic salt (Na2CO3) in the form of either powder or solution. When the treated ash was re-injected into the combustor with the fuel, the effect on SO2 removal efficiency was negligible if Na2CO3 was added as powder. Doping with aqueous solution resulted in enhanced SO2 removal; however, the extent was lower than the level achieved if only water hydration was employed. Increasing the amount of water (from 10% to 30%) to reactivate the ash did not improve the sulphur capture capacity in the mini-CFBC. Overall, this study suggests that the most practical way for re-use of the partially sulphated bed ash as a sulphur sorbent is reactivation by water. A proposal for utilization of the fly ash in an economically reasonable way is also discussed.

  10. 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.

  11. Mapping ash properties using principal components analysis

    Science.gov (United States)

    Pereira, Paulo; Brevik, Eric; Cerda, Artemi; Ubeda, Xavier; Novara, Agata; Francos, Marcos; Rodrigo-Comino, Jesus; Bogunovic, Igor; Khaledian, Yones

    2017-04-01

    In post-fire environments ash has important benefits for soils, such as protection and source of nutrients, crucial for vegetation recuperation (Jordan et al., 2016; Pereira et al., 2015a; 2016a,b). The thickness and distribution of ash are fundamental aspects for soil protection (Cerdà and Doerr, 2008; Pereira et al., 2015b) and the severity at which was produced is important for the type and amount of elements that is released in soil solution (Bodi et al., 2014). Ash is very mobile material, and it is important were it will be deposited. Until the first rainfalls are is very mobile. After it, bind in the soil surface and is harder to erode. Mapping ash properties in the immediate period after fire is complex, since it is constantly moving (Pereira et al., 2015b). However, is an important task, since according the amount and type of ash produced we can identify the degree of soil protection and the nutrients that will be dissolved. The objective of this work is to apply to map ash properties (CaCO3, pH, and select extractable elements) using a principal component analysis (PCA) in the immediate period after the fire. Four days after the fire we established a grid in a 9x27 m area and took ash samples every 3 meters for a total of 40 sampling points (Pereira et al., 2017). The PCA identified 5 different factors. Factor 1 identified high loadings in electrical conductivity, calcium, and magnesium and negative with aluminum and iron, while Factor 3 had high positive loadings in total phosphorous and silica. Factor 3 showed high positive loadings in sodium and potassium, factor 4 high negative loadings in CaCO3 and pH, and factor 5 high loadings in sodium and potassium. The experimental variograms of the extracted factors showed that the Gaussian model was the most precise to model factor 1, the linear to model factor 2 and the wave hole effect to model factor 3, 4 and 5. The maps produced confirm the patternd observed in the experimental variograms. Factor 1 and 2

  12. PEMANFAATAN FLY ASH SEBAGAI BAHAN CAMPURAN PEMBUATAN PORTLAND POSSOLAN CEMENT (PPC (Utilization of Fly Ash as A Mixing in Portland Pozzolan Cement (PPC Production

    Directory of Open Access Journals (Sweden)

    Ambo Upe

    2006-11-01

    Full Text Available ABSTRAK Fly ash atau abu terbang (Kode Limbah D 22.3 merupakan salah satu produk hasil pembakaran batubara yang dihasilkan PT. Semen Tonasa sebesar rata-rata 72.36 ton/hari. Telah dicoba memanfaatkan fly ash sebagai bahan campuran semen untuk menghasilkan Portland Pozzolan Cement (PPC. Selain itu, dilakukan uji Toxicity Characteristic Leaching Procedure (TCLP serta analisis kandungan logam berat dari fly ash dan PPC tersebut.  Hasil perocobaan menunjukkan bahwa fly ash memenuhi persaratan sebagai bahan campuran PPC dan memenuhi syarat peraturan pemerintah No.85/1999 tentang Pengelolaan Llimbah Bahan Berbahaya dan Beracun.   ABSTRACT Fly ash (Disposal code: D 223 is disposal produced in coal burning process of PT. Semen Tonasa. It is estimated that the produced fly ash are 72.36 ton/day. In this paper, the study examines the possibility of utilization the fly ash as a mixing material in fabrication of Portland Pozzoland Cement (PPC. Experimental results show that the produced PPC meets the standard quality requirement. The Toxicity Characteristic Leaching Procedure (TCLP also has been performed to analysis the heavy metal contained in the fly ash and PPC materials. This test indicates that all results for TCLP Metals property fill the Indonesian Government Regulation for Hazardous Waste as described in PP No. 85/1999

  13. HIS 103 ASH course tutorial/tutorialoutlet

    OpenAIRE

    NARESH 1

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   HIS 103 Week 1 DQ 1 (Transition to Agriculture) (Ash) HIS 103 Week 1 DQ 2 (Early Complex Societies) (Ash) HIS 103 Week 1 Quiz (Ash) HIS 103 Week 1 Assignment (Ash) HIS 103 Week 2 Assignment Greco Roman Influence Paper (Ash) HIS 103 Week 2 DQ 1 Chinese Social and Political Order Systems (Ash) HIS 103 Week 2 DQ 2 Caste System (Ash) HIS 103 Week 2 Quiz (Ash) HIS 103 Week 3 Assignment Black Death Dra...

  14. Emerald Ash Borer (Coleoptera: Buprestidae)

    Science.gov (United States)

    The emerald ash borer, Agrilus planipennis Fairmaire, is an invasive beetle from Asia that has caused large scale ash (Fraxinus spp.) mortality in North America. This book chapter reviews the taxonomy, biology, life history of this invasive pest and its associated natural enemies in both its native ...

  15. 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...

  16. Rheological Characterization of Isabgol Husk, Gum Katira Hydrocolloids, and Their Blends

    Directory of Open Access Journals (Sweden)

    Vipin Kumar Sharma

    2014-01-01

    Full Text Available The rheological parameters of Isabgol husk, gum katira, and their blends were determined in different media such as distilled water, 0.1 N HCl, and phosphate buffer (pH 7.4. The blend properties of Isabgol husk and gum katira were measured for four different percentage compositions in order to understand their compatibility in dispersion form such as 00 : 100, 25 : 50, 50 : 50, 75 : 25, and 100 : 00 in the gel strength of 1 mass%. The miscibility of blends was determined by calculating Isabgol husk-gum katira interaction parameters by Krigbaum and Wall equation. Other rheological properties were analyzed by Bingham, Power, Casson, Casson chocolate, and IPC paste analysis. The study revealed that the power flow index “p” was less than “1” in all concentrations of Isabgol husk, gum katira, and their blends dispersions indicating the shear-thinning (pseudoplastic behavior. All blends followed pseudoplastic behavior at thermal conditions as 298.15, 313.15, and 333.15°K and in dispersion media such as distilled water, 0.1 N HCl, and phosphate buffer (pH 7.4. Moreover, the study indicated the applicability of these blends in the development of drug delivery systems and in industries, for example, ice-cream, paste, nutraceutical, and so forth.

  17. Pantoea ananatis as a Cause of Corneal Infiltrate after Rice Husk Injury

    Science.gov (United States)

    Manoharan, Geetha; Jeganathan, Lakshmi Priya; DSilva, Sean Socrates; Prajna, N. Venkatesh

    2012-01-01

    We report a case of an agricultural worker presenting with corneal infiltrate following ocular injury with a rice husk. On examination, a superficial corneal foreign body was removed and sent for culture, which grew Pantoea ananatis. This is, to our knowledge, the first clinical case report of Pantoea ananatis causing corneal infiltrate. PMID:22461671

  18. Synthesis of SiC from rice husk in a plasma reactor

    Indian Academy of Sciences (India)

    S K Singh; B C Mohanty; S Basu

    2002-11-01

    A new route for production of SiC from rice husk is reported by employing thermal plasma technique. The formation of -SiC is observed in a short time of 5 min. The samples are characterized by XRD and SEM.

  19. Sorption of Pb2+ from Aqueous Solution unto Modified Rice Husk: Isotherms Studies

    Directory of Open Access Journals (Sweden)

    A. O. Dada

    2013-01-01

    Full Text Available Investigation of the sorption potential of rice husk, an agricultural waste, as an adsorbent was carried out. The rice husk was modified with orthophosphoric acid and was used for adsorption of lead (II ions (Pb2+ from aqueous solution. Physicochemical properties of the modified rice husk were determined. Equilibrium sorption data were confirmed with Langmuir, Freundlich and Temkin adsorption isotherms. On the basis of adsorption isotherm graphs, R2 values were determined to be 0.995, 0.916, and 0.797 for Langmuir, Temkin, and Freundlich isotherms, respectively, indicating that the data fitted well into the adsorption isotherms, but Langmuir isotherm is a better model. The maximum monolayer coverage from Langmuir studies, Qmax=138.89 mg/g, Langmuir isotherm constant, KL=0.699 L/mg, and the separation factor, RL=1.41×10−2 at 100 mg/L of lead(II ions indicating that the sorption process, was favourable. The suitability of modified rice husk as an adsorbent for the removal of lead ions from aqueous solution and its potential for pollution control is established.

  20. Synthesis of silicon carbide from rice husk in a packed bed arc reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, P.K.; Nayak, B.B.; Mohanty, B. [Regional Research Lab., Bhubaneswar (India)

    1995-09-01

    Silicon carbide in the form of powder was prepared from boiler burnt rice husk in a new type of packed bed arc reactor where the raw materials were processed in briquette form. X-ray diffraction analysis identified the presence of both {beta} and {alpha} SiC. Microstructural characterization revealed the presence of triangular, truncated triangular, and hexagonal crystallites, along with platelets.

  1. Biological detoxification of Cr(VI) using wood-husk immobilized Acinetobacter haemolyticus

    Energy Technology Data Exchange (ETDEWEB)

    Zakaria, Zainul Akmar; Zakaria, Zainoha [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Surif, Salmijah [Department of Environmental Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Ahmad, Wan Azlina [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia)], E-mail: azlina@kimia.fs.utm.my

    2007-09-05

    Acinetobacter haemolyticus, a Gram-negative aerobic locally isolated bacterium, immobilized on wood-husk showed the ability to detoxify Cr(VI) to Cr(III). Wood-husk, a natural cellulose-based support material, packed in an upward-flow column was used as support material for bacterial attachment. Around 97% of the Cr(VI) in wastewater containing 15 mg L{sup -1} of Cr(VI) was reduced at a flow rate of 8.0 mL min{sup -1}. The wastewater containing Cr(VI) was added with liquid pineapple wastewater as nutrient source for the bacteria. Electron microscopic examinations of the wood-husk after 42 days of column operation showed gradual colonization of the wood-husk by bacterial biofilm. The use of 0.1% (v/v) formaldehyde as a disinfecting agent inhibited growth of bacteria present in the final wastewater discharge. This finding is important in view of the ethical code regarding possible introduction of exogenous bacterial species into the environment.

  2. A Study of the Anechoic Performance of Rice Husk-Based, Geometrically Tapered, Hollow Absorbers

    Directory of Open Access Journals (Sweden)

    Muhammad Nadeem Iqbal

    2014-01-01

    Full Text Available Although solid, geometrically tapered microwave absorbers are preferred due to their better performance, they are bulky and must have a thickness on the order of λ or more. The goal of this study was to design lightweight absorbers that can reduce the electromagnetic reflections to less than −10 dB. We used a very simple approach; two waste materials, that is, rice husks and tire dust in powder form, were used to fabricate two independent samples. We measured and used their dielectric properties to determine and compare the propagation constants and quarter-wave thickness. The quarter-wave thickness for the tire dust was 3 mm less than that of the rice husk material, but we preferred the rice-husk material. This preference was based on the fact that our goal was to achieve minimum backward reflections, and the rice-husk material, with its low dielectric constant, high loss factor, large attenuation per unit length, and ease of fabrication, provided a better opportunity to achieve that goal. The performance of the absorbers was found to be better (lower than −20 dB, and comparison of the results proved that the hollow design with 58% less weight was a good alternative to the use of solid absorbers.

  3. Isolation, characterization and investigation of Plantago ovata husk polysaccharide as superdisintegrant.

    Science.gov (United States)

    Pawar, Harshal; Varkhade, Chhaya

    2014-08-01

    Psyllium husk (Plantago ovata, Family: Plantaginaceae) contains a high proportion of hemicellulose, composed of a xylan backbone linked with arabinose, rhamnose, and galacturonic acid units (arabinoxylans). Polysaccharide was isolated from Psyllium husk using solvent precipitation method. The isolated polysaccharide was evaluated for various physicochemical parameters. The rheological behavior of polysaccharide (1% w/v in water) was studied using Brookfield viscometer. Polysaccharide derived from the husk of P. ovata was investigated as superdisintegrant in the fast dissolving tablets. Valsartan, an antihypertensive drug, was selected as a model drug. The tablets of Valsartan were prepared separately using different concentrations (1, 2.5, 5, 7.5% w/w) of isolated Plantago ovata (P. ovata) husk polysaccharide (Natural) and crospovidone as a synthetic superdisintegrant by direct compression method. The prepared tablets were evaluated for various pre-compression and post-compression parameters. The drug excipient interactions were characterized by FTIR studies. The formulation F4 containing7.5% polysaccharide showed rapid wetting time and disintegration time as compared to formulation prepared using synthetic superdisintegrant at the same concentration level. Hence batch F4 was considered as optimized formulation. The stability studies were performed on formulation F4. The disintegration time and in vitro drug release of the optimized formulation was compared with the marketed formulation (Conventional tablets).

  4. 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)

    2014-01-01

    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 (K2CO3) and alkaline-earth metal (CaCO3) 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, Ca9(K,Mg,Fe)(PO4)7, for all fuels and fuel mixtures. With the addition of potassium, cristobalite (SiO2) could no longer be identified via X-ray diffraction (XRD) in the bed ash particles and leucite (KAlSi2O6) was formed. Most of the alkaline-earth metals calcium and

  5. Nutritive composition of soybean by-products and nutrient digestibility of soybean pod husk

    Directory of Open Access Journals (Sweden)

    Sompong Sruamsiri

    2008-11-01

    Full Text Available Soybean by-products (soybean germ, soybean milk residue, soybean hull, soybean pod husk and soybean stem were subjected to proximate analysis, and in vitro digestibility of DM (IVDMD, ADF (IVADFD and NDF (IVNDFD were determined after digesting the by-products in buffered rumen fluid for 24 or 48 h in 2 ANKOMII Daisy Incubators using Completely Randomised Design. Four native cattle (body weight 210 + 13.5 kg were used to determine nutrient digestibility of soybean pod husk. They were randomly assigned by Cross-over Design to receive two roughage sources, i.e. guinea grass and guinea grass + soybean pod husk (60:40 DM basis, in two experimental periods. Guinea grass was harvested on the 35th day after the first cut of the year and used as green forage. Total collection method was used to determine the digestibility coefficients and digestibility by difference was used to calculate nutrient digestibility of soybean pod husk.The nutritive composition showed that soybean germ was highest in CP content (42.27% of DM and EE content (5.07% of DM but lowest in NDF and ADF content (20.09 and 21.53% of DM respectively. The average CP content of soybean straw, soybean stem and soybean pod husk was low (4.91, 4.67 and 5.04% respectively, while ADF content was high (42.76, 38.01 and 42.08% respectively. In vitro digestibility of DM (IVDMD, ADF (IVADFD and NDF (IVNDFD showed that all of them, except soybean stem, can be used as cattle feed, e.g. as supplemented feed or admixture in concentrate feed. Digestibility coefficients of guinea grass were higher in CP, CF and EE when compared to the other groups. The apparent digestibility of CP and CF were highly different (P0.05. The digestibility of nutrients (DM, OM, CP, CF, NFE, NDF and ADF of soybean pod husk were 53.81 + 4.3, 59.69 + 4.6, 42.38 + 3.8, 30.71 + 3.2, 50.74 + 4.3, 75.26 + 4.0, 45.78 + 3.7 and 30.53 + 4.2 % respectively. Soybean pod husk was higher in total digestible nutrients (TDN (51.87 + 3.3 vs

  6. A Review on Recycling Ash Derived from Elaeis guineensis By-product

    Directory of Open Access Journals (Sweden)

    Zhong Xian Ooi

    2014-09-01

    Full Text Available Oil palm (Elaeis guineensis ash is defined as the waste generated after the combustion of oil palm biomass. Malaysia is one of the world’s largest producers and exporter of palm oil in the world, and there is approximately 4 million tonnes of oil palm ash generated annually. It is estimated that the amount of oil palm ash will keep increasing due to the high demand for palm oil globally. Normally, oil palm ash is disposed without any beneficial economic return value. The awareness of this environmental crisis has increased significantly over the past few years. With the evolution of ash utilization strategies, interest in oil palm ash in various research fields has grown. Through the effort of researchers and information available, the properties of the resulting materials are affected by the percentage of substitution and particle size of the oil palm ash. The major challenges in utilizing oil palm ash are discussed in this paper, as are the beneficial effects, which can include reducing the negative environmental impact and the product cost. Although the recycling of oil palm ash is still a new focus of interest, the main thrust of waste management in Malaysia will continue to focus on this kind of research and will attempt to solve the problem of disposal of the ash as well.

  7. Composition, diagenetic transformation and alkalinity potential of oil shale ash sediments

    Energy Technology Data Exchange (ETDEWEB)

    Motlep, Riho, E-mail: riho.motlep@ut.ee [Department of Geology, University of Tartu, Ravila 14A, 50411 Tartu (Estonia); Sild, Terje, E-mail: terje.sild@maaamet.ee [Estonian Land Board, Mustamaee tee 51, 10621 Tallinn (Estonia); Puura, Erik, E-mail: erik.puura@ut.ee [Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu (Estonia); Kirsimaee, Kalle, E-mail: kalle.kirsimae@ut.ee [Department of Geology, University of Tartu, Ravila 14A, 50411 Tartu (Estonia)

    2010-12-15

    Oil shale is a primary fuel in the Estonian energy sector. After combustion 45-48% of the oil shale is left over as ash, producing about 5-7 Mt of ash, which is deposited on ash plateaus annually almost without any reuse. This study focuses on oil shale ash plateau sediment mineralogy, its hydration and diagenetic transformations, a study that has not been addressed. Oil shale ash wastes are considered as the biggest pollution sources in Estonia and thus determining the composition and properties of oil shale ash sediment are important to assess its environmental implications and also its possible reusability. A study of fresh ash and drillcore samples from ash plateau sediment was conducted by X-ray diffractometry and scanning electron microscopy. The oil shale is highly calcareous, and the ash that remains after combustion is derived from the decomposition of carbonate minerals. It is rich in lime and anhydrite that are unstable phases under hydrous conditions. These processes and the diagenetic alteration of other phases determine the composition of the plateau sediment. Dominant phases in the ash are hydration and associated transformation products: calcite, ettringite, portlandite and hydrocalumite. The prevailing mineral phases (portlandite, ettringite) cause highly alkaline leachates, pH 12-13. Neutralization of these leachates under natural conditions, by rainwater leaching/neutralization and slow transformation (e.g. carbonation) of the aforementioned unstable phases into more stable forms, takes, at best, hundreds or even hundreds of thousands of years.

  8. Utilization of municipal solid waste incineration ash in Portland cement clinker

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Charles Hoi King; Barford, John Patrick; McKay, Gordon [Hong Kong University of Science and Technology, Department of Chemical and Biomolecular Engineering, Hong Kong (China)

    2011-08-15

    Municipal solid waste incineration (MSWI) ash is used in part as raw materials for cement clinker production by taking advantage of the high contents of SiO{sub 2}, Al{sub 2}O{sub 3}, and CaO. It is necessary for environmental reasons to establish a material utilization system for the incineration waste ash residue instead of disposing these ashes into landfill. The aim of this paper is to study the feasibility of replacing clinker raw materials by waste ash residue for cement clinker production. MSWI bottom ash and MSWI fly ash are the main types of ashes being evaluated. The ashes were mixed into raw mixture with different portions of ash residue to produce cement clinker in a laboratory furnace at approximately 1400 C. X-ray diffraction and X-ray fluorescence techniques were used to analyze the phase chemistry and chemical composition of clinkers in order to compare these ash-based clinkers with commercial Portland cement clinker. (orig.)

  9. Utilization of ash fractions from alternative biofuels used in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Nikolaisen, L.; Hinge, J.; Christensen, I. (Danish Technological Inst., Aarhus (Denmark)); Dahl, J. (Force Technology, Broendby (Denmark)); Arendt Jensen, P. (DTU-CHEC, Kgs. Lyngby (Denmark)); Soendergaard Birkmose, T. (Dansk Landbrugsraadgivning, Landscentret, Aarhus (Denmark)); Sander, B. (DONG Energy, Fredericia (Denmark)); Kristensen, O. (Kommunekemi A/S, Nyborg (Denmark))

    2008-07-15

    It is expected, that demand for the traditional biomass resources wood and straw will increase over the next years. In other projects a number of agro industrial waste products has been tested and characterized as fuels for power plants. The annual production in Denmark of these fuels is estimated at roughly 400.000 tons of Dry Matter per year, so the potential is substantial. The agro industrial biomass products include: Grain screening waste, pea shells, soy waste, cocoa waste, sugar beet waste, sunflower waste, shea waste, coffee waste, olive waste, rice shell waste, potato waste, pectin waste, carrageen waste, tobacco waste, rape seed waste and mash from breweries. In the PSO project 5075, 5 different types of fuel pellets was produced, which were rendered suitable for combustion in power plants. In this project, ash is produced from the above mentioned 5 mixtures together with another 2 mixtures produced especially for this project. From the 5 mixtures from PSO 5075, ash is produced at Danish Technological Institute's slag analyzer. These ash products are rendered comparable to ash from grate fired boilers at power plants. The ash/slag from the combustion in the slag analyzer was then grinded - thus resulting in a total of 5 ash products. At DTU CHEC's Entrained Flow Reactor, ash products from the 5+2 mixtures were produced. These ash products are rendered comparable to ash produced form suspension fired boilers at power plants. For each of the 7 mixtures, bottom-, cyclone and filter ash was taken out separately resulting in a total of 21 ash samples. The produced ashes have been evaluated for their properties as directly applied fertilizer. Furthermore, scenarios have been set up to assess the feasibility in producing artificial fertilizer from the ash products, based on known processes. In the main components the content of Na, S, Cl and K is significantly higher in filter ashes, whereas the content of Mg, Al, Si and Ca is significantly lower. The

  10. Technology for processing ash from thermal/electric plants without waste products

    Energy Technology Data Exchange (ETDEWEB)

    Tyurnikova, V.I.; Krasnikova, N.A.; Panin, A.S.; Konovalenko, P.F.

    1979-07-01

    Possibility of using flotation for enriching volatile ash from heating/electric power stations are investigated. On ash samples containing 9 percent carbon from the Nikolaev thermal/ electric plant, it was demonstrated that by using flotation with an apolar collector and T-66 reagent, the ash content was increased to 98.6% permitting it to be used for producing high ash construction materials. A foam carbon-containing product from the process has a heat of combustion of 4,000 kilocalories/ kilogram and can be reused as a fuel. Flowsheet for the flotation process is presented.

  11. [Study on mercury re-emissions during fly ash utilization].

    Science.gov (United States)

    Meng, Yang; Wang, Shu-Xiao

    2012-09-01

    The amount of fly ash produced during coal combustion is around 400 million tons per year in China. About 65%-68% of fly ash is used in building material production, road construction, architecture and agriculture. Some of these utilization processes include high temperature procedures, which may lead to mercury re-emissions. In this study, experiments were designed to simulate the key process in cement production and steam-cured brick production. A temperature programmed desorption (TPD) method was used to study the mercury transformation in the major utilization processes. Mercury re-emission during the fly ash utilization in China was estimated based on the experimental results. It was found that mercury existed as HgCl2 (Hg2 Cl2), HgS and HgO in the fly ash. During the cement production process, more than 98% of the mercury in fly ash was re-emitted. In the steam-curing brick manufacturing process, the average mercury re-emission percentage was about 28%, which was dominated by the percentage of HgCl2 (Hg2 Cl2). It is estimated that the mercury re-emission during the fly ash utilization have increased from 4.07 t in 2002 to 9.18 t in 2008, of which cement industry contributes about 96.6%.

  12. Removal of pollutants from wastewater by coal bottom ash.

    Science.gov (United States)

    Lin, Chiu-Yue; Yang, Dong-Hao

    2002-09-01

    Coal bottom ash produced from a thermal power plant was used in a batch experiment to investigate the adsorption characteristic of this bottom ash. The adsorbate solutions were synthetic wastewaters contained copper (Cu2+) or COD and a sanitary landfill leachate. The influences of various factors, such as contact time, pH, initial adsorbate concentration and temperature on the sorption have been studied. Experimental results show that coal bottom ash had a good adsorption capacity for copper and COD and could reduce the concentrations of various pollutants in the leachate. The adsorption capacities of each gram of coal bottom ash were 0.48 mg Cu (at pH 4 and temperature 25 degrees C) and 7.5 mg COD (at pH 5 and temperature 25 degrees C); their adsorption behaviors conformed to Freundlich's adsorption model. In treating leachate, the removal efficiencies of COD, NH3--N, total Kjeldah nitrogen, phosphorus, Fe3+, Mn2+ and Zn2+ were 47, 39.4, 31.1, 92.9, 96.5, 94.3 and 82.2%, respectively. Based on these results we can conclude that it is possible to use coal bottom ash for removing pollutants from wastewaters. The adsorption capacities of coal bottom ash for pollutants were also determined.

  13. 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).

  14. Electroremediation of straw and co-combustion ash under acidic conditions

    DEFF Research Database (Denmark)

    Lima, Ana T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2009-01-01

    Biomass, such as wood and straw, is currently used in EU as a renewable energy source for energy production and this application is expected to rise in coming years. Combined heat and power installations produce fly ash, which is considered hazardous waste. The fly ash management issue should...... be addressed before biomass combustion is considered a truly sustainable technology. The electrodialytic process is a remediation technique able to assist the management of fly ash. For this work, straw and co-combustion of wood ash are briefly characterized and their electrodialytic treatment is carried out...... similarities with wood ash alone. However, further characterization should be carried out before any comparison regarding applicable legislation. Under acidic conditions, the electrodialytic treatment was not effective for the co-combustion wood ash. The heavy metals appeared in the least soluble fraction...

  15. Screening of Surface Medication Agents and Modification Mechanism of Fly Ash

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-bo; WEI Lu-bin

    2007-01-01

    The fly ash from Jixi power plant was treated with various surface modifiers. The surface properties of the modified fly ash, including active index wetting angle, were measured in this paper. The modified fly ash was filled into rubber to improve the rubber properties. The results of rubber tests indicate that the type of the surface modifiers has a great influence on the rubber reinforcing properties. The fly ash modified by titanate coupling agents exhibits the best performance in respect to rubber reinforcing properties. The test results show that the fly ash can take place of some decomposition material so that the dosage of decomposition in rubber can be reduced, resulting in the low producing cost of rubber and the low pollution of fly ash.

  16. Screening of surface medication agents and modification mechanism of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Hong-bo Zhang; Lu-bin Wei [China University of Mining & Technology, Beijing (China). School of Chemical and Environmental Engineering

    2007-09-15

    The fly ash from Jixi power plant was treated with various surface modifiers. The surface properties of the modified fly ash, including active index wetting angle, were measured in this paper. The modified fly ash was filled into rubber to improve the rubber properties. The results of rubber tests indicate that the type of the surface modifiers has a great influence on the rubber reinforcing properties. The fly ash modified by titanate coupling agents exhibits the best performance in respect to rubber reinforcing properties. The test results show that the fly ash can take place of some decomposition material so that the dosage of decomposition in rubber can be reduced, resulting in the low producing cost of rubber and the low pollution of fly ash. 8 refs., 6 figs., 3 tabs.

  17. 掺烧稻壳对煤粉炉飞灰特性的影响%EFFECT OF CO-FIRING ON THE CHARACTERISTIC OF FLY ASH IN 300MWel PC BOILER

    Institute of Scientific and Technical Information of China (English)

    鲁许鳌; 阎维平; 沈冶; 袁光福; 蒋国平

    2011-01-01

    在某300MW机组煤粉锅炉上进行稻壳掺烧试验,掺烧后飞灰的性质发生变化.对掺烧后锅炉飞灰的微观形貌、化学性质和稻壳灰的孔隙结构等性质进行试验分析.发现:掺烧稻壳后飞灰的物相中出现鳞石英和方石英晶形,飞灰中稻壳灰呈现熔融后块状的不规则颗粒物和黑色的大粒径的不规则片状灰粒,SiO2的含量从掺烧前的55.93%增加到75.05%.利用压汞仪对稻壳灰的孔隙特性进行分析.稻壳和煤共燃的飞灰的利用方式需要重新评估,而分离的稻壳灰可用作多孔材料.%The test of co-firing of rice husk and coal was carried on PC boiler of 300MWel unit. The characteristics of the flying ash of co-firing change. The microscopic appearance, the chemical property of the fly ash and the pore structure of the rice husk ash(RHA) were studied. During co-firing, there are the cristobalite and tridymite crystal in the fly ash.RHA presents two kinds: massive anomalous particles and black size laminated ash power; the Si02 content of the fly ash of co-firing to increasing from 55.93% to 75.05%. The pore characteristics of RHA was studied by mercury porosimeter.The using methods of the fly ash of co-firing will be re-evaluated. However, the dee husk ash separated of co-firing can be use for porous material.

  18. Initializing HYSPLIT with satellite observations of volcanic ash: A case study of the 2008 Kasatochi eruption

    Science.gov (United States)

    Crawford, Alice M.; Stunder, Barbara J. B.; Ngan, Fong; Pavolonis, Michael J.

    2016-09-01

    The current work focuses on improving volcanic ash forecasts by integrating satellite observations of ash into the Lagrangian transport and dispersion model, HYSPLIT. The accuracy of HYSPLIT output is dependent on the accuracy of the initialization: the initial position, size distribution, and amount of ash as a function of time. Satellite observations from passive infrared, IR, sensors are used both to construct the initialization term and for verification. Space-based lidar observations are used for further verification. We compare model output produced using different initializations for the 2008 eruption of Kasatochi in the Aleutian Islands. Simple source terms, such as a uniform vertical line or cylindrical source above the vent, are compared to initializations derived from satellite measurements of position, mass loading, effective radius, and height of the downwind ash cloud. Using satellite measurements of column mass loading of ash to constrain the source term produces better long-term predictions than using an empirical equation relating mass eruption rate and plume height above the vent. Even though some quantities, such as the cloud thickness, must be estimated, initializations which release particles at the position of the observed ash cloud produce model output which is comparable to or better than the model output produced with source terms located above and around the vent. Space-based lidar data, passive IR retrievals of ash cloud top height, and model output agree well with each other, and all suggest that the Kasatochi ash cloud evolved into a complex three-dimensional structure.

  19. Particle size and compositional retrievals of the Chaiten volcanic ash from spaceborne, high spectral resolution infrared AIRS and IASI measurements

    Science.gov (United States)

    Prata, F.; Gangale, G.; Clarisse, L.

    2008-12-01

    The eruption of Chaiten volcano in early May 2008 produced copious amounts of ash and little SO2 gas. The ash clouds could be detected very well by several satellite instruments, but was unusual in that true- colour daytime MODIS satellite imagery showed the ash to be quite light in colour and difficult to distinguish from ordinary meteorological clouds. High spectral resolution infrared spectrometer and interferometer measurements from AIRS and IASI were analysed to investigate the spectral signature of the Chaiten ash clouds and compare these with ash clouds from other volcanoes, which generally appear much darker in visible imagery. It was found that the Chaiten ash had a distinctive spectral signature between 800 to 1200 wavenumbers and that this correlated very well with the signature expected from rhyolitic ash. A radiative transfer code and an ash microphysical model were used to retrieve the mean particle size of fine ash in the Chaiten clouds and best fits were found for rhyolitic particles with small (less than 2 micron) radii. These results suggest that infrared spectra may be used to retrieve both compositional and particle size information in ash clouds. Based on the spectral signatures found for these ash clouds, a new ash detection algorithm was designed and found to have improved sensitivity to thin (low opacity) ash clouds and low sensitivity to surface effects. The new algorithm offers the possibility of tracking ash clouds for longer periods of time and over greater distances. Results from both the AIRS and IASI measurements are presented for the May ash clouds from Chaitén volcano and compared with the signatures of ash clouds from andesitic volcanic clouds and quartz dominated windblown dust.

  20. Wildland fire ash: Production, composition and eco-hydro-geomorphic effects

    Science.gov (United States)

    Bodi, Merche B.; Martin, Deborah; Balfour, Victoria N.; Santin, Cristina; Doerr, Stefan H.; Pereira, Paulo; Cerda, Artemi; Mataix-Solera, Jorge

    2014-01-01

    Fire transforms fuels (i.e. biomass, necromass, soil organic matter) into materials with different chemical and physical properties. One of these materials is ash, which is the particulate residue remaining or deposited on the ground that consists of mineral materials and charred organic components. The quantity and characteristics of ash produced during a wildland fire depend mainly on (1) the total burned fuel (i.e. fuel load), (2) fuel type and (3) its combustion completeness. For a given fuel load and type, a higher combustion completeness will reduce the ash organic carbon content, increasing the relative mineral content, and hence reducing total mass of ash produced. The homogeneity and thickness of the ash layer can vary substantially in space and time and reported average thicknesses range from close to 0 to 50 mm. Ash is a highly mobile material that, after its deposition, may be incorporated into the soil profile, redistributed or removed from a burned site within days or weeks by wind and water erosion to surface depressions, footslopes, streams, lakes, reservoirs and, potentially, into marine deposits.Research on the composition, properties and effects of ash on the burned ecosystem has been conducted on material collected in the field after wildland and prescribed fires as well as on material produced in the laboratory. At low combustion completeness (typically T  450 °C), most organic carbon is volatized and the remaining mineral ash has elevated pH when in solution. It is composed mainly of calcium, magnesium, sodium, potassium, silicon and phosphorous in the form of inorganic carbonates, whereas at T > 580 °C the most common forms are oxides. Ash produced under lower combustion completeness is usually darker, coarser, and less dense and has a higher saturated hydraulic conductivity than ash with higher combustion completeness, although physical reactions with CO2 and when moistened produce further changes in ash characteristics.As a new