Process Development and Techno-Economic Analysis (TEA) of Ethanol Production from Switchgrass Using Superpro Designer Software

Abstract

In this paper switchgrass biomass has been investigated as an energy crop for ethanol production, and the techno-economic analysis is conducted using SuperPro Designer software. Switchgrass is a perennial herbaceous plant, and in US, there are five variety of switchgrass varied like Alamo and Kanlow across different lowlands, and the upland plants included the varieties of Trailblazer, Cave in Rock, Blackwell. Ethanol can be produced from cellulose and hemicellulose, and lignin can be separated as co-product and lignin is not used for conversion to ethanol. The maximum cellulose content belongs to Blackwell and Alamo cultivars which are 33.65% and 33.48 % respectively.; the highest hemicellulose and lignin contents with cave-in-rock cultivar like 26.32% and 18.36%. In addition, the compositions of polysaccharide sugars in the different switchgrass cultivars the maximum glucan (36.60%) and mannan (0.80%) are in Kanlow cultivar, Xylan (21.17%) in Trailblazer, Galactan (1.16%) in cave-in-rock, arabinan (3.01%) in Blackwell. For 1000MT/day ethanol production from switchgrass, a process flow diagram, block diagram and table about process descriptions are developed using SuperPro designer software, and all the process parameters are assumed and used based on the literature. The selling price of produced ethanol is $ 0.9/kg and $ 3.4/gallon based on economic evaluation by SuperPro Designer. Total amount of ethanol produced 90 million gallons per year and total lignin produced 2,20,440 MT/yr and the lignin selling price is assumed $ 0.5/kg. Based on the economic and profitability analysis the developed design process for ethanol production from switchgrass is profitable one with payback time around 10 years.