Fly ash is categorized into two types C-type, F-type. Fly ash contains majorly calcium oxide, silica, and alumina. In Tables 1 and 2 physical and chemical properties of POFA are tabulated.įly ash is obtained from electricity generation in thermal power plants coal is combusted, during this process a byproduct fly ash is formed. In Landfills, the disposal of palm oil fuel is being as a waste, these many cause environmental problems. ![]() POFA are used in super structures and long span bridges mainly for precast, pre stressed girders and high raised skyscrapers. The obtained ash is collected, pulverized and passed through IS 90 mm sieve. It is estimated that approximately 4 kgs of dry biomass is produced to produce one kg of palm oil. Fiber waste and shells of palm kernel are burned in chimneys to produce heat at a temperature of 450 ☌. In Tables 1 and 2 physical and chemical properties of metakaolin are tabulated.įrom agro-waste of palm oil, POFA is obtained. For every production of one ton of metakaolin leads to 175 kgs of CO 2 emission, which is very less when compared to Portland clinkers. In concrete, metakaolin is used as replacement material. For maintaining the consistency of concrete and to produce high strength concrete, Metakaolin is used as an admixture. It is a non-crystalline amorphous and cementitious material. It is high quality pozzolonic material which is effective in increasing strength and reduces the sulphate attack.particle size of metakoalin is smaller compared to cement particles. Metakaolin is a white powder of Al 2O 3.2SiO 2 and obtained from the calcinating of pure kaolinite clay at an ambient temperature of 650 0 850 ☌. In Tables 1 and 2 physical and chemical properties of silica fume are tabulated. These protect the steel from corrosion in coastal region. Adding of silica fume decreases the permeability of concrete to the chloride ions. The particle size is which is 90% of SiO 2 and other constituents are Sulphur, Carbon and aluminium oxides, potassium, Fe, Ca. Silica fume is obtained from coal with quartz reduction in an electric arc furnace and is waste bi-product of manufacturing silicon or Ferro silicon alloys. Silica fume is used as an artificial pozzolonic admixture which is also called as micro silica or condensed silica fume. Silica Fume used as a partly or complete substitute of cement which increases the concrete properties. The usage of silica fume has been increased worldwide over recent years which can enhance the permeability, strength and durability. įirstly, silica fume used in 1969 in Norway but was employed in North America and Europe in early’s 1980. Usage of supplementary cementitious materials in the preparation of concrete can leads to significant energy savings, cost savings and environmental pollution reduction. Effect on fresh concrete due to mineral admixtures shows variation in mechanical and durability properties compared to conventional concrete. Also problems with disposal may reduce because these admixtures are industrial by-products. ![]() By incorporating these admixtures cement content get reduced which minimize environment impact and the properties of concrete also increases. Mineral admixtures influence the hardened properties of concrete. ![]() Quality of concrete can be improved by adding different mineral admixtures: metakaolin, GGBS, Fly Ash, Rice Husk Ash, Palm Oil Fuel Ash and Silica Fume. In some studies, different mineral admixtures are used as replacement of cement. In some studies, aggregates are replaced by palm oil shells which are waste product in agriculture industry and this is used as light weight aggregate. Waste materials which are produced from industries can be used in concrete by replacing either aggregates or cement. mineral admixtures, compressive strength of concrete increases. In developing countries, demand for Portland cement is growing significantly.
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