Novel applications of dividing‐wall column technology to biofuel production processes

Abstract

Biofuels enjoy nowadays increased public and scientific attention, driven by key factors such as volatile oil price, the need for increased energy security, and concerns over greenhouse gas emissions from fossil fuels. However, in order to make biofuels a competitive alternative, the cost of production has to be significantly reduced by using enhanced process technologies. Distillation is heavily involved in the production processes of biofuels -taking the blame for the high energy requirements that have a negative impact on the operating costs. Dividing-wall column (DWC) is one of the best examples of proven industrial process intensification technology in distillation, as it allows significantly lower investment and operating costs while also reducing the number of equipment units and the carbon footprint.This work presents an overview of novel applications using the DWC technology in the production of the most important biofuels, by employing multi-component separations, azeotropic, extractive or reactive distillation in a DWC: enhanced methanol recovery and glycerol separation in biodiesel production, synthesis of fatty acid methyl esters and dimethyl ether (DME) by reactive distillation, integrated DME purification and methanol or CO 2 recovery in the dimethyl ether process, as well as bioethanol concentration and dehydration. The industrially relevant case studies presented here show that significant energy savings are possible (ranging from ∼20 to 60%) while simplifying the processes by using less equipment that requires a lower plant footprint. Remarkably, in most cases there is also the possibility of revamping existing plants producing biofuels, and thus reusing the already available equipment.Dimethyl ether (DME) is the simplest aliphatic ether, with notable properties: non-toxic colorless gas, non-corrosive, noncarcinogenic and environmentally friendly. 7 As a clean fuel, DME wileyonlinelibrary.com/jctb

From laboratory experiments to simulation studies of methanol dehydration to produce dimethyl ether reaction—Part II: Simulation and cost estimation

“…By process integration, the feed components can be distilled and separated with a small amount of utilities consumption [7,8]. The main advantage of a DWC is its possibility in saving both energy and capital costs [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. The theoretical studies have shown that DWCs save at least 30 % of energy costs compared to the conventional schemes [7][8][9].…”

Optimization of Reactive Dividing‐Wall Distillation Column for Ethyl t‐Butyl Ether Synthesis

“…Purification of such processes by simple distillation is not possible. The reactive dividing‐wall distillation column (RDWC) was used for such reaction and separation systems . The production of biofuels and fuel additives inside a single unit of RDWC was found to be an attractive approach.…”

Design of dividing wall columns for butanol recovery in a thermochemical biomass to butanol process

“…However, these energy and capital costs of the separation section can potentially be improved by utilizing DWCs for biobutanol recovery instead of conventional distillation columns, leading to a reduction in production costs of the process and thus have a significant impact in improving the competitiveness of biobutanol as a gasoline replacement. This application of DWC technology has not been previously investigated for biobutanol recovery from a thermochemical process, and is an interesting area of research as past research has demonstrated the benefits of DWC applications to bioethanol, bioDME and biodiesel production processes [16,17].…”