Bioethanol process

The widespread use of papers has created an enormous amount of wastepaper however, it is not easy to recycle this resource because of the high cost of its utilization process. In the past, recycled wastepaper was used only two to three times before the fibers became unacceptably short (1). This wastepaper can be used in the bioethanol process as inexpensive... 

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. 

In the present study, pretreatment of whole-crop maize silage was studied with the aim of optimizing the bioethanol process. The influence of temperature, time, and pH on sugar recovery and yield after pretreatment and enzymatic hydrolysis was studied as well as the ethanol yield in simultaneous saccharification and fermentation (SSF) with S. cerevisiae. 

Chen X, Shekiro J, Franden MA, Wang W, Zhang M, Kuhn E, Johnson DK, Tucker MP. (2012). The impacts of deacetylation prior to dilute acid pretreatment on the bioethanol process. Biotechnol Biofuels, 5, 8-22. 

The impacts of deacetylation prior to dilute acid pretreatment on the bioethanol process. Biotechnol Biofuels, 5, 8. 

As an example of how sustainabihty considerations can be incorporated along with the economic and profitabiUty analysis, two bioethanol processes, as shown in Figs. 6.1 and 6.2, are evaluated. Com dry grind and wet milling processes are two most widely... 

In this example the steady-state simulation of two bioethanol processes is conducted by modifying the model developed by McAloon et al. using Aspen Plus and Microsoft Excel, where the non-random two Hquid thermodynamic model is used [41,43,44]. The plant capacity is considered to be 100 milhon gal per year (378.5 km per year) for both cases. The simulation results shown in Tables 6.2—6.4 provide information on the overall input and output material, component balance, and utihty consumption for both cases. 

For the social criteria, two methods are applied in this study. A more detailed safety-related discussion of the bioethanol process can be found in the open Hterature [45]. In the first method, safety during operation, operability of the plant, safe startup and shutdown, and location-specific demands are selected as four soft indicators for sustainability assessment. The evaluation and justification of each indicator are provided in Table 6.13, where standard definition and scaling system can be found in Othman et al. [1]. In this approach, the process with the higher score is more desirable. Again the dry grind process is found to be superior. 

Balat, M., Balat, H., 6z, C., 2008. Progress in bioethanol processing. Progress in Energy and Combustion Science 34 (5), 551—573. Available at http //www.sciencedrrect.cotn/science/ article/pii/S0360128507000706 (accessed 22.01.15.). 

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