Risk assessment and technical feasibility of usage of paper mill sludge biochar-based exhausted adsorbent for geopolymeric brick formation (original) (raw)
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The immobilisation of heavy metals from sewage sludge ash in geopolymer mortars
MATEC Web of Conferences
Sewage sludge is a semi-solid waste material created as a result of the sewage treatment of industrial or municipal wastewater. Because the laws and regulations of the European Union require not only a reduction in waste generation but also the preparation of waste for reuse and disposal, it is necessary to look for new methods of the application of sewage sludge as part of sustainable waste management. In this study, ash formed as a result of the combustion of sewage sludge from the sewage treatment plant in Płaszów, Krakow in a fluidised bed furnace at a temperature of around 800°C was used. Sewage sludge ash (SSA) contains over 30% SiO2 and approx. 10% Al2O3, which indicates potential applications in geopolymer materials. In this study, samples of geopolymer mortars with a binder containing sewage sludge ash as well as fly ash (FA) and ground granulated blast furnace slag (GGBFS) were prepared. The mechanical parameters were determined after 2, 7, 14, and 28 days. The results sho...
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This paper investigates the immobilization behaviors of Cd2+, Pb2+ and Hg2+ ions in a geopolymer based on water treatment sludge (WTS) and dealuminated metakaolin (DaMK) solid waste from alum industry. For synthesis of WTS/DaMK based geopolymer, five mixes of WTS/DaMK (75/25, 80/20, 85/15, 90/10 and 95/5, respectively) are tested to obtain the optimum synthesis condition based on the compressive strength. Results showed that the geopolymer mortar with 85/15WTS/DaMK has the highest compressive strength (8 MPa). In addition, X-ray Diffraction (XRD) and X-ray Fluorescence (XRF) techniques are used to characterize the mineral and chemical compositions of WTS and DaMK. WTS/DaMK based geopolymer mortar have been tested for leaching to study its immobilization behavior under the optimum condition. The Cd2+, Pb2+ and Hg2+ ions were used and effectively immobilized in this study. The heavy metals with concentrations of 100, 200 and 300 ppm were used in the geopolymer matrix giving about 98% ...
DEVELOPMENT OF AMBIENT CURED GEOPOLYMER BRICKS
IAEME PUBLICATION, 2021
Geopolymer brick is a substitute for the burnt type clay bricks. The conventional bricks causes serious hazardous effect to the environment due to soil degradation and carbon dioxide emission. In this research work, alternative bricks – geopolymer bricks were produced by combining fly ash and GGBS (Ground Granulated Blast Furnace Slag) with river sand. A binder is a combination of sodium hydroxide and sodium silicate which is used as an activator. Ambient curing of geopolymer bricks was done and no other energy intensive process was involved in curing the geopolymer bricks. In this study, three combinations of geopolymer bricks were cast by varying the proportions of fly ash and GGBS – (90%+10%), (80%+20+), (75%+25%) and found their compressive strength as 9.50 MPa, 12.84 MPa and 15.93 MPa respectively. Geopolymer brick with 75 % fly ash and 25% GGBS shows higher compressive strength and better resistance to chemicals. The strength of 230 x 105 x 70mm geopolymer brick was compared with 230 x 105 x 70mm fly ash brick and 225 x 110 x 75mm burnt clay brick.
DURABILITY STUDIES ON COAL RESIDUE AND SUGARCANE RESIDUE BASED GEOPOLYMER BRICKS
IRJET, 2016
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Review on Adsorption of Heavy Metal in Wastewater by Using Geopolymer
Rapid development of advanced technology in Malaysia gave impact increasing in the accumulation of heavy metal every day in our daily life through wastewater. Long term exposure of human bodies to heavy metals susceptible to receives various infections and diseases. From an environmental and economic perspective, adsorption is acceptable process that can be applied in wastewater treatment. However, usage of activated carbon most acknowledged and costly adsorbents lead people to find an alternative to activated carbon. Several studies of physical properties of geopolymer make them gain attention to replace an activated carbon in the treatment of heavy metal. This paper review adsorption of heavy metal by using geopolymer.