Field Crop 2024, Vol.7, No.2, 116-123 http://cropscipublisher.com/index.php/fc 117 greenhouse gas emissions. The value-added utilization of by-products can maximize the economic benefits of the sugarcane industry, expand new sources of income, and improve industrial competitiveness, it can also create local employment opportunities and promote rural economic development. However, the value-added utilization of sugarcane by-products still faces many challenges, such as technical challenges, some value-added technologies are not yet mature, or there are technical bottlenecks on an industrial scale; economic feasibility, the economic benefits of some value-added utilization methods have not been fully proven; policies and regulations The impact is the lack of a complete policy support system and incentive mechanism. Promoting the value-added utilization of sugarcane by-products requires the joint efforts of technology, economics and policy to achieve the transformation from "waste" to "wealth" and contribute to global sustainable development and circular economy. 1 Classification and Characteristics of Sugarcane By-products 1.1 Characteristics of sugarcane bagasse Bagasse is the main solid by-product produced after squeezing juice from sugarcane stems during the sugar production process. It is a fibrous biomass residue, accounting for approximately 25% to 30% of the weight of each ton of sugarcane. As a major by-product of the sugarcane industry, bagasse has significant utilization potential and is produced in large quantities globally. Brazil produces approximately 28 million tons of bagasse every year, and globally, it is expected to produce approximately 279 million tons of bagasse every year, with abundant resource reserves (Ajala et al., 2021). Sugarcane bagasse is a typical lignocellulosic biomass. Its main components are cellulose, hemicellulose and lignin. Cellulose accounts for about 45%, hemicellulose accounts for 32%, lignin accounts for 17%, and the rest is trace. Minerals and ash cellulose and hemicellulose provide the potential of bagasse as a fermentation substrate and the production of biomaterials, while lignin provides the calorific value, making it useful as biomass fuel (Wang et al., 2022). Sugarcane bagasse can be used as raw material for the production of biomass energy and biofuels, producing ethanol, biogas, biodiesel, etc. Through technologies such as pretreatment and enzymatic hydrolysis, cellulose and hemicellulose can be converted into fermentable sugars for the production of fuels such as bioethanol (Ajala et al., 2021). Pretreatment methods include alkali method, acid method, steam explosion, etc., which can effectively improve enzymatic hydrolysis efficiency and increase sugar production (Wang et al., 2022). Bagasse is an important raw material for the paper industry, especially in major sugar-producing countries such as Brazil and India. Through techniques such as alkaline pretreatment and mechanical separation, sugarcane bagasse can be made into pulp for the production of paper and paper products. In recent years, high value-added materials such as nanocellulose have gradually become potential uses for bagasse. In addition to biofuels and pulp, bagasse can also be used to produce a variety of high value-added chemicals and materials, such as xylitol, nanocellulose, biochar, etc. Through appropriate pretreatment and hydrolysis processes, soluble sugars can be extracted from sugarcane bagasse and used to produce sweeteners such as xylitol. At the same time, the ash after burning sugarcane bagasse is rich in minerals and can be used as a soil conditioner and fertilizer. 1.2 Characteristics of molasses Molasses is the main liquid by-product produced in the sugar industry. It is the viscous liquid remaining during the multiple crystallization processes of sugarcane juice. Each ton of sugar cane can produce about 2.2%~3.7% molasses, which is a tan high-viscosity liquid with a density of about 1.4~1.5 g/mL. Its main components include 30%~35% sucrose, 10%~25% glucose and fructose, and other non-sugar compounds (such as organic acids, minerals and vitamins) (Hawaz et al., 2023). The economic importance of molasses makes it an important carbon source in the food, feed and fermentation industries. Currently molasses is mainly used in ethanol production and as an animal feed additive, but is also widely used in the production of rum, dry yeast, acetone and butanol, among others. In addition, molasses also has
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