Sweet Sorghum as Feedstock for Biofuel Production: A Review

Abstract

Fossil energy resources, the primary source of transport fuel in the world is depleting dramatically to meet the ever-increasing energy demands globally. Crop plants are one of the best sources of renewable energy which can be used as feedstock for biofuel production. Sweet sorghum [Sorghum bicolor (L.) Moench], a C 4 Graminaceous crop which has sugar-rich stalks and which is a water-use efficient crop has a very good potential as an alternative feed stock for ethanol production. It is the only crop that provides grain and stem that can be used for sugar, alcohol, syrup, jaggery, fodder, fuel, bedding, roofing, fencing, paper and chewing. Sweet sorghum juices usually contain approximately 16-18% fermentable sugar, which can be directly fermented into ethanol by yeast. Technical challenges of using sweet sorghum for biofuels are a short harvest period for highest sugar content and fast sugar degradation during storage. Various review works based on the problems of sweet sorghum were described in this review. Some studies are on the genetic potential of sweet sorghum for higher green cane yield and juice extractability where as some studies are purely on the shelf life of the juice how to preserve the juice with low cost against bacterial contamination. Studies also involve testing the potential of genotypes for superior yields of cane during post rainy and summer seasons also to make the cane available for maximum period in a year. Studies on fermentation and hydrolysis of lignocellulose are also addressed in this review.

Chemical-free Processing of Sweet Sorghum Juice of Cultivar Sucrosorgho 506

“…A recent review gives comprehensive conception about sweet sorghum as an energy crop and summarizes processing methods aiming a wide variety of product both from juice and bagasse [53]. Another study was specialized on biofuel production [54], and another one gives a summary of sweet sorghum as an energy crop [55]. Syrup production for nutritional purposes however, fell outside the scope of interest.…”

Water Use of Fossil Energy Production and Supply in China

“…To address this situation, China continues to develop alternative energy strategies and push towards a clean energy plan [13,14], including wind, solar, and biological energy. However, China's non-fossil fuels, as a share of primary energy consumption, are still relatively low due to energy efficiency and economic problems [15]. The primary energy consumption structure and the energy consumption in China from 2001 to 2020 (the date for the years 2001,2005,2010, and 2015 were extracted from China Energy Statistical Yearbook 2015 [16], and date for the year 2020 was extracted from the '13th Five Year Plan for energy' section published by the National Development and Reform Commission [17]) show that fossil energy has been the foundation of the country's national economy and social development and holds a pivotal status in China.…”

Promoción De Biomasa Y Contenido De Azúcares en Sorgo Dulce Mediante Abonos Orgánicos Y Micorriza Arbuscular

“…El caso del sorgo dulce (Sorghum bicolor), presenta ventajas comparativas, no compite con cultivos de granos y tiene bajos costos de producción, requiere 36 % menos nitrógeno que el maíz para lograr rendimientos similares de etanol (Ratnavathi et al 2011). Es una gramínea de fotosíntesis C 4 , tolerante a la sequía, de rápido crecimiento, que acumula grandes cantidades de azúcares fermentables en el tallo y de biomasa, posee amplia adaptabilidad y tolera condiciones adversas de producción, además su siembra es factible en áreas no aptas para otros cultivos (Ratnavathi et al 2011, Calviño y Messing 2012.…”

“…Es una gramínea de fotosíntesis C 4 , tolerante a la sequía, de rápido crecimiento, que acumula grandes cantidades de azúcares fermentables en el tallo y de biomasa, posee amplia adaptabilidad y tolera condiciones adversas de producción, además su siembra es factible en áreas no aptas para otros cultivos (Ratnavathi et al 2011, Calviño y Messing 2012. Por lo anterior se puede utilizar para la producción de azúcar refinada, alcohol y gasolina, entre otros (House et al 2002, Lemus y Parrish 2009, Ratnavathi et al 2011. Es importante señalar que el uso de biocombustibles produce energía limpia y eficiente (Prasad et al 2007, Almodares y Hadi 2009.…”