A replacement of traditional insulation refractory brick by a waste‐derived lightweight refractory castable

Abstract

Lightweight insulation refractories are essential for high‐temperature performance to reduce energy consumption. This study investigates a new insulation material, that is, solid waste rice husk ash (RHA) derived lightweight refractory castable, replacing traditional insulation refractory brick. The RHA is generated after the burning of rice husk as biomass fuel. The RHA is used as an aggregate and alkali‐extracted silica sol from RHA as a binder to fabricate the insulation castable. The nanosilica containing (~30 wt%) sol is employed to synthesize the refractory castable by varying the sol amount (2.5‐12.5 wt% silica from sol). The castable specimens are cast by a vibro‐caster and fired at 900‐1200°C in a muffle furnace. The physic‐mechanical and thermal conductivity (κ) of the castable is investigated. At 1100°C with 10 wt% dry sol retaining sample shows an excellent apparent porosity (~65%), low bulk density (~ 0.8 g/cm3), and κ (0.136 W/m k) with sustainable compressive strength (6 MPa). The acquired results are a good match with the literature (other wastes‐derived insulation materials) and industrial (silica insulation brick) obtained data. These promising outcomes may inspire the refractory industries for using RHA as an aggregate and RHA extracted sol as a binder for making insulation castable.

Preparation of insulating firebricks using date seeds

“…One inconvenience is the need to have them ground to a size roughly ranging from 0.5 to 1mm. However, all other types of waste used in similar studies, like sugar cane bagasse [10] or coal [11], or rice husks [12] or other seeds [13] require initial treatment involving either grinding or shredding.…”

“…The substitution of conventional insulating refractory bricks by a refractory castable was suggested by Hossain et al [12] using rice husk. Their product showed a low bulk density of 0.8 g.cm -3 , when fired at 1100 o C corresponding to a porosity of 65% and a thermal conductivity of 0.136 W.m -1 K -1 and a cold compressive strength of 6MPa.…”

Genetic dissection of monosaccharides contents in rice whole grain using genome‐wide association study

“…The caryopsis consists of pericarp outer layers, seed coat, embryo (germ), and the endosperm (Juliano, 2016; Upadhyay & Karn, 2018). Rice is an important crop used as staple food in many countries, and following dehusking and milling of the paddy rice, the resultant husk (20% of harvest and rich in silica) and bran (10% of harvest) can be used in industries such as agriculture (as biological control agents, soil fertilizers, mushroom subdtrates and mulching), food and feed, water refining, dye removal, fuel and other energy resources, construction materials (ceramics, concrete, and firebrick) (Abdul Wahab et al., 2020; Edrisi et al., 2018; Urtecho et al., 2019; Hossain et al., 2021; Lat Reano, 2020; Sala et al., 2020; Win et al., 2019), and for remediation purposes (Carraro et al., 2021; Pham, 2020; Shamsollahi & Partovinia, 2019; Yulnafatmawita et al., 2020) in a circular bioeconomy fashion. With many available genetic resources and a completely sequenced genome, rice has been considered as a model system for grass cell wall research (Li et al., 2018).…”

Utilization of industrial wastes in Al2O3‐SiC‐SiO2‐C refractories: Characterization of erosion and corrosion resistance

“…[6][7][8][9] On the other hand, the waste primarily consists of oxides, which are comparable to the components of refractories; hence, using waste in refractories is a viable alternative. [10][11][12][13] Furthermore, due to the high-cost of raw materials, there is a trend to use low-cost industrial waste in refractories by partially replacing expensive commercial raw material for blast furnaces, kilns, and incinerators, particularly during the current recession. 14,15 Kumar et al 16,17 used ferro-chromium slag as aggregate to prepare a castable refractory with great compressive strength values using.…”

“…Numerous literatures on industrial waste utilization in partial substitution of concrete for construction have been reported for replacement applications 6–9 . On the other hand, the waste primarily consists of oxides, which are comparable to the components of refractories; hence, using waste in refractories is a viable alternative 10–13 . Furthermore, due to the high‐cost of raw materials, there is a trend to use low‐cost industrial waste in refractories by partially replacing expensive commercial raw material for blast furnaces, kilns, and incinerators, particularly during the current recession 14,15 .…”