Continuous Calcination of Biocoke/Petcoke Blends in a Rotary Tube Furnace

Abstract

The aluminum industry relies on calcined petroleum coke as an anode material for the smelting of aluminum oxide into aluminum metal. While distillate residues from biomass pyrolysis oils can convert into calcined coke with promising elemental and physical properties, no studies have produced calcined biocoke continuously from rotary kilns. Using a solids feeder and rotary tube furnace, blends of green petroleum coke and biocoke underwent continuous calcination. The biocoke from pyrolysis bio-oil distillation residues contained ∼13 wt % oxygen. In control experiments, the furnace converted green petroleum coke into calcined petroleum coke within industry specifications. Properties measured include % anisotropy (indicated by polarized light microscopy), porosity, crystallite thickness (L c ), and trace element concentrations. With biocoke blends (10 and 27 wt %), the effects on properties increased with respect to the blend concentration. Microscopy and X-ray diffraction indicated the blends to be mostly anisotropic with some amorphous domains remaining in the blended product. Steady-state sulfur concentrations decreased from 3.2 to 2.7 wt %. Nickel and vanadium successfully decreased to desirable limits, especially when 27 wt % biocoke was used. Adding biocoke increased phosphorous and titanium concentrations by 5−7 and 10 ppm, respectively. Blending 27 wt % biocoke with green petroleum coke to produce calcined coke for aluminum smelting anodes can reduce direct greenhouse gas emissions and the acidification potential by 54 and 27%, respectively, avoiding the emission of ∼800 kg CO 2 e and 0.7 kg SO 2 e for each metric ton of primary aluminum produced.

Progress on Biobased Industrial Carbons as Thermochemical Biorefinery Coproducts

“…However, these results were recently followed up by successful scale-up of biocoke calcination through a continuous rotary tube furnace. 80 In contrast to other works, specific metals concentrations were analyzed and discussed. In general, animal waste-based biomass yielded more phosphorus into the char and residues compared with wood or grassy biomasses, demonstrating that despite significant processing the initial biomass feedstock will still influence the properties of biocoke.…”

“…Figure displays polarized light micrographs which display typical morphologies of CPC, alongside those obtained from Elkasabi and co-workers. , While coke results were promising, no anode formulations or tests were conducted, outside of some microscale experiments measuring electrical conductivity and apparent density. However, these results were recently followed up by successful scale-up of biocoke calcination through a continuous rotary tube furnace . In contrast to other works, specific metals concentrations were analyzed and discussed.…”

Improve the Compressive Strength Using a Strength Improver Agent (Sia) in the Cement Industry in Indonesia

“…As a result, cement producers are competing fiercely by taking into account several factors, such as production costs, energy efficiency, quality, selling price, and environmental issues [3]. In the kiln, which involves the reaction of calcium carbonate, contributes significantly to the release of greenhouse gas emissions, particularly CO2 [4,5]. In other words, an increase in cement production capacity can potentially contribute to global warming problems if not carefully addressed [5,6].…”