TABLE OF CONTENTS Xiuzhi Susan Sun
Biorefining can be defined as a process that converts whole grains and legumes or fiber residues into useful fractions, chemicals, and polymers by physical, chemical, or enzymatic methods or by microorganism conversion technologies. Protein, oil, lignin, and carbohydrate are major materials that can be found in the grains and legumes presented in Table 1.2 in Chapter 1. Based on a particular plant s nature, one can always find one of these materials in any kind of grain or legume. These materials are often coproducts of each other in a plant. Biorefinery technologies for manufacturing these polymers and materials are generally similar, but they do vary depending on differences in composition and structure from one plant to another. This chapter focuses on the concepts and technologies used in biorefining to isolate protein, starch, and oil-based polymers out of grain and legumes, but our discussion is limited to bioconversion and to the energy and mass balance of a biorefinery system.
Two major approaches are commonly used for oil extraction: mechanical extraction and solvent extraction. Mechanical extraction has a long history, and it is the simplest and safest technology for oil extraction. Figure 3.1 presents a typical mechanical extractor for oil extraction [1]. The principle of mechanical oil extraction is to apply mechanical forces to rupture the beans, cells, and oil bodies, and then squeeze out the oil. Heat is usually generated in the barrel due to intensive shearing, which may...
