NO emission from the combustion of mixed fuel pellets of Fenton/CaO-conditioned municipal sludge and rice husk

Abstract Rice husk has a great potential in its calorific value and silica content in ash which makes its valorization through combustion becomes important and interesting. This study presents the thermodynamics simulation performance of rice husk combustion using a realistic decomposition approach. A non-ideal gas approach and fugacity coefficient were also considered in the calculation. From this study, rice husk is devolatilized to form gases (63.37%), tar (8.69%), char (27.94%), and all of these are then oxidized to form flue gas. The realistic decomposition approach calculated that about 2.6 MJ/kg of specific combustion energy is produced, the maximum combustion temperature is up to 1457oC for perfect insulation condition, and up to 1400oC if there is a heat loss. It is found that combustion equipped with larger excess air could quench the heat produced and reduce the combustion efficiency but could maintain the temperature at 700oC. Furthermore, the thermodynamics simulation expressed that NO emission amount from rice husk combustion is negligible and there is still a probability for CO and H2 to be produced at above 500oC due to Boudouard reaction and homogeneous water gas shift reaction (WGSR). The study showed that a realistic decomposition approach could predict the rice husk combustion performance with a reasonable and logical result. Supplying excess air of about 180–200% is advantageous to keep the combustion temperature at 700oC in order to prevent silica crystalline formation which harms human health, as well as suppressing NO emission and reducing CO emission from the simultaneous Boudouard and WGSR.

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Refused derived fuel pellets from municipal solid waste and rice husk

Bangladesh Journal of Scientific and Industrial Research ◽

10.3329/bjsir.v54i4.44567 ◽

2019 ◽

Vol 54 (4) ◽

pp. 329-338

Author(s):

MK Iqbal ◽

A Nadeem ◽

MT Butt

Keyword(s):

Municipal Solid Waste ◽

Solid Waste ◽

Bulk Density ◽

Rice Husk ◽

Retention Time ◽

Mechanical Characteristics ◽

Hydraulic Press ◽

Quadratic Model ◽

Fuel Pellets ◽

Binder Concentration

The objective of this study was to optimize the parameters for the development of refused derived fuel (RDF) pellets from municipal solid waste (MSW) and rice husk by using Response Surface Methodology (RSM). In this a systematic study was conducted, where three parameters were varied according to RSM factorial design. The binder concentration (5-10%) pressure (700-1200 psi) and retention time (3-7 minutes) were used for RDF pellet development under hydraulic press, measured hardness bulk density (BD) and durability (DU). The T3 treatment results revealed the highest pellet hardness, bulk density, and durability 25 kg, 805 kg/m3, 99% respectively by application binder concentration (5%), pressure (1200 psi) and retention time (5 minutes). The experimental data on response variables were fitted into quadratic polynomial model using the multiple regression analysis and found that it was statistically significant quadratic model. The RDF physical chemical and mechanical characteristics were also evaluated and found their relationship between HHV, carbon, ash, DU, BD and energy density. The ash contents were inversely proportional to DU and HHV whereas DU was directly related to BD. Bangladesh J. Sci. Ind. Res.54(4), 329-338, 2019

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Production and characterization of fuel pellets from rice husk and wheat straw

Renewable Energy ◽

10.1016/j.renene.2019.06.048 ◽

2020 ◽

Vol 145 ◽

pp. 500-507 ◽

Cited By ~ 21

Author(s):

Inés M. Ríos-Badrán ◽

Iván Luzardo-Ocampo ◽

Juan Fernando García-Trejo ◽

José Santos-Cruz ◽

Claudia Gutiérrez-Antonio

Keyword(s):

Wheat Straw ◽

Rice Husk ◽

Fuel Pellets

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Fuel Pellets from a Mixture of Rice Husk and Wood Particles

BioResources ◽

10.15376/biores.12.3.6618-6628 ◽

2017 ◽

Vol 12 (3) ◽

Author(s):

Porferio O. Bajo Jr ◽

Menandro N. Acda

Keyword(s):

Rice Husk ◽

Fuel Pellets ◽

Wood Particles

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Mechanoactivation Of Rice Husk Ash In Laboratory Conditions

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.11.20-26 ◽

2019 ◽

pp. 20-26

Keyword(s):

Mechanical Activation ◽

Rice Husk ◽

Amorphous Silica ◽

Silicon Oxide ◽

Rice Husk Ash ◽

Pozzolanic Activity ◽

Maximum Solubility ◽

Laboratory Conditions ◽

Before And After ◽

Mineral Additive

In many rice producing countries of the world, including in Vietnam, various research aimed at using rice husk ash (RHA) as a finely dispersed active mineral additive in cements, concrete and mortars are being conducted. The effect of the duration of the mechanoactivation of the RHA, produced under laboratory conditions in Vietnam, on its pozzolanic activity were investigated in this study. The composition of ash was investigated by laser granulometry and the values of indicators characterizing the dispersion of its particles before and after mechanical activation were established. The content of soluble amorphous silicon oxide in rice husk ash samples was determined by photocolorimetric analysis. The pizzolanic activity of the RHA, fly ash and the silica fume was also compared according to the method of absorption of the solution of the active mineral additive. It is established that the duration of the mechanical activation of rice husk ash by grinding in a vibratory mill is optimal for increasing its pozzolanic activity, since it simultaneously results in the production of the most dispersed ash particles with the highest specific surface area and maximum solubility of the amorphous silica contained in it. Longer grinding does not lead to further reduction in the size of ash particles, which can be explained by their aggregation, and also reduces the solubility of amorphous silica in an aqueous alkaline medium.

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