Use of Heavy Oil Fly Ash as a Color Ingredient in Cement Mortar

Abstract

Heavy oil fly ash (HOFA) is a byproduct generated by the burning of heavy fuel oil. Chemical analysis showed that HOFA is mainly composed of unburned carbon with a significant amount of heavy metals. Due to toxicity, management of this waste poses a challenge to the industry personal. The present study investigates the possible use of HOFA as a black pigment or admixture in cement mortar aiming to produce ornamental brick. In order to investigate the change of cement mortar strength when HOFA is added, the standard compressive strength test with 50 mm cubes was performed. The results showed that the addition of 2-5 % of HOFA in cement mortar does not affect its strength. The leaching behavior of trace elements within HOFA and HOFA mixed mortar were investigated through laboratory batch leaching experiments. The results confirmed that HOFA can be utilized as a black pigment in ornamental brick, which is environmentally safe and provides good balance between color and brick properties.

Characterization, Processing, and Application of Heavy Fuel Oil Ash, an Industrial Waste Material – A Review

“…concluded from the XRD analysis that HFOA consists of amorphous carbon and crystallites of metallic oxides, such as quartz, faujasite, aluminosilicate (mullite), zeolite, and cancrinite [30] . Similarly, other groups have reported the amorphous nature of carbon [26,29,31,32,33,34] . In contrast, Al Ghouti et al., using XRD analysis, reported that carbon in HFOA generated in a Jordanian thermal power plant was crystalline in nature [17] .…”

“…[30] Similarly, other groups have reported the amorphous nature of carbon. [26,29,31,32,33,34] In contrast, Al Ghouti et al, using XRD analysis, reported that carbon in HFOA generated in a Jordanian thermal power plant was crystalline in nature. [17] Likewise, it was reported to be crystalline in other studies.…”

“…In a study on the addition of HFOA as an admixture in cement mortar specimens to develop an ornamental brick, it was found that an optimum quantity of 2-5 % HFOA exhibited no reduction in compressive strength and based on the laboratory leaching experiments, was environmentally safe. [34] A soil stabilization study with the addition of HFOA in two Saudi Arabian soil types, namely sand and marl, were conducted by Al-Malack et al [47] The authors reported that the strength of marl with 5 % of both HFOA and cement satisfied the ACI requirements. [120] However, higher additions (i. e., 10 % and 15 % of HFOA) decreased the soil strength to less than that of the ACI requirements.…”

“…In a study on the addition of HFOA as an admixture in cement mortar specimens to develop an ornamental brick, it was found that an optimum quantity of 2–5 % HFOA exhibited no reduction in compressive strength and based on the laboratory leaching experiments, was environmentally safe [34] …”

Carbon rich fly ash and their nanostructures

“…Coal fly ash can be categorized into two distinct classes, i.e., F and C. Class F fly ash is produced as a result of burning anthracite or sometimes bituminous coal. On the other hand, class C fly ash is produced by burning sub-bituminous coal or lignite [1]. This classification is based on the sum of the major oxides present in the fly ash, such as silicon dioxide (SiO 2 ), ferric oxide (Fe 2 O 3 ) and aluminum oxide (Al 2 O 3 ).…”