Production costs, bioethanol

Bioethanol upgrading and valorization is another area in which catalysis will be a key player. The decrease in ethanol production cost and the need to realize a transition to a society based more on renewables are two driving forces to develop new catalytic processes for bioethanol conversion. However, without improvements in the efficiency and selectivity of the various processes for ethanol, and in general biomass conversion, which are possible only by the introduction of better and/or new catalysts, this transition to a bio-based economy will probably not be possible. Research on catalysis will thus be the enabling factor for this change towards a more sustainable society. 

Biofuels such as bioethanol and biodiesel originate from cereal crops such as plant oils, and sugar beets. Today the production cost of bioethanol cereal crops is still too high, which is the major reason why bioethanol has not made its breakthrough as a fuel source yet. When producing bioethanol from maize or sugar cane the raw material constitutes about 40-70% of the production cost. 

Production Costs of Jerusalem Artichoke for Bioethanol Production in Denmark in 1987... 

Xylose is the major sugar present in the hemicellulose fraction of agricultural residues, such as wheat straw. Because the raw material cost is greater than one-third of the overall ethanol production cost [5], fermentation of xylose together with glucose is needed to improve the economics of any lignocellulosic-based bioethanol process. 

From the above described current state of the production of bioethanol (or any other platform chemical) from lignoceUulose, the following limitations can be identified. The substrate costs have a decisive influence on the final liter price of the ethanol these must be kept as low as possible in order to be able to compete with other fuels. However, as the price of the raw materials is dependent on supply and demand, they are difficult to either predict or control. Additionally, on account of its complex structure lignoceUulose is not easUy broken down by enzymes. 

The success of utilizing cellulosic materials for the production of fuels, such as bioethanol, and chemicals depends heavily on reducing the costs of enzyme technology. Enzyme use for the production of bioethanol from sugar and starch has grown significantly and as a result Novozymes is investing 160-200 million in a new enzyme production facility in Nebraska, USA. 

The reduction of the bioethanol cost and the increase of its competitiveness depend greatly on the production technology. Bioethanol technology consists of two phases the prodirction of raw ethanol and its further del dration. Azeotropic distillation, adsorption on molecular sieves and evaporation through the membrane are rrsed for ethanol delydration of [8]. 

Production cost of bioethanol usii different technologies, ... 

Bioethanol with the lowest cost is obtained by the evaporation through the membrane independently of the type of raw material for processing. Thus, when the bioethanol production from the sugar beet (cmde juice) by the azeotropic distillation was used, the production cost of 1 ton of bioethanol was USD 1447.5 ( 1.14 per 1 L), and when the evaporation through the membrane was used - 1378.2 ( 1.09 per 1 L) or decreased by 4.8%. 

The analogical dependence occurred when the bioethanol production from green blackstrap molasses, symp and molasses took place. The lowest production cost of bioethanol from molasses was obtained while using all three processing technologies. Thus, the production of bioethanol from the molasses by azeotropic distillation the production cost of 1 ton of bioethanol was 934.7 ( 0.74 per 1 L), and it decreased by 7.4% - to 865.5/t ( 0.69 per 11) when the evaporation through the membrane was used. 

The calculations of the bioethanol production cost from sugar beet by-products show that the competitiveness ensures the bioethanol production from molasses using the evaporation through the membrane. 

Bioethanol Competitiveness Molasses Production cost Sugar... 

More recently, in order to overcome the disadvantages of conventional fermentation systems, Lewandowicz et aL (2011) used a continuous fermentation process based on a bioreactor coupled with an MD unit. The MD technique for removing bioethanol from a reactor is able to maximise the volumetric productivity, and thus minimise production costs in the biofuel industry. Moreover, the combined system also facilitates a reduction in yeast stress, which commonly occurs in industrial fermentation. The experimental campaign was carried out using a module with 40 microporous hydrophobic... 

In all technical PE production processes, the cost for the ethylene feedstock accounts by far for the largest share, typically 70% (for the LDPE autoclave process) to 78% (for the HOPE fluid bed process). Therefore, PE production costs depend heavily on the ethene price, which means, today, on the crude oil price. In the light of this dependency, attempts to produce PE from bioethanol-derived or for coal-derived ethene become understandable. 

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