Process simulation of cassava cellulosic ethanol production with low to medium-pressure steam heat integration

Energy demand tends to increase by 80% in 2050 due to the rapid growth of the global population. However, the energy resources rapidly decrease for responding to the global need. Many previous researchers suggest the ideas for solving this situation and the most interesting solution is the heat integration which intends to produce cost-effective energy with minimal impact on the environment. Energy integration thus should be noticeable for the industry process to minimize the loss along the industrial process. The ethanol production process is interested in this study because it can add value to agricultural products like cassava which is an industrial crop in several countries and produces ethanol products that can decrease the usage of gasoline. Here, the heat integration model was developed for the ethanol production process by using low to medium-pressure steam. For the simulation model, the ethanol production process used the cellulose content as the main inlet component to be easy for applicable corresponding to feed casava cellulosic substances. The process contained three sections including enzymatic hydrolysis, simultaneous saccharification fermentation (SSF), and fractional distillation. The quality and quantity of low to medium-pressure steam were investigated for maintaining the operation of the enzymatic hydrolysis reactor by varying steam pressure between 1–2 atm and steam temperature between 100–105 °C. The results achieved the methodology to find optimum conditions by the ratio between steam flow rate and product quantity. The best case could reduce 6.49% of the excessive usage of low to medium-pressure steam which pointed out the way to use the energy efficiently

Effect of raw material structural composition on the fermentation process of ethanol production

Ethanol is becoming the important renewable energy sources in the world which produces from carbohydrate resources. The raw material selection is the important procedure for real industrial production. The effect of biomass structural composition in feedstock on ethanol production is therefore needed to explore for feedstock selection. According to the previous research studies, the fermentation process includes pre-treatment and fermentation of sugar to ethanol. This study focuses on the simulation of raw material variation in ethanol production especially the structural composition of carbohydrate that contains three main components, cellulose, xylan, and lignin, in the fermentation section. The simulation model is validated by the data of previous study information with small deviation. The mixture design method is used for result interpretation and analysis. From the design of experiment, there are 14 scenarios and the selected response parameter is the mass fraction of ethanol in outlet stream of fermentation section. From the results, the maximum mass fraction of ethanol in outlet stream is in the scenario which has a large amount of cellulose and xylan fractions. This is because the conversion of reaction in the fermentation reactor mostly consumes cellulose and xylan to produce glucose and xylose, respectively, and converts them into ethanol product. From the overall result of this study, the important of raw material selection in ethanol production is illustrated