This book focuses on the mechanical engineering of plastics wastes, fibrous materials, micro- and nano-grinding of biomaterials and wastes, powder product energy properties, and their power, energy, effectiveness measurement and applications. These topics are explained starting from the interactions between individual particles up to the design of grinding systems. A wide range of problems are discussed, such as flow obstructions, segregation, and vibrations. The goal is to provide a deeper understanding of the process of precise grinding of nonbrittle materials and to show effective design, technology, and maintenance solutions. The book comprises theoretical and experimental analysis of energy systems'¬" effectiveness, various properties of grinders design and innovations, efficiency and effectiveness of grinding technical systems and environment, research methods and grinding preparation techniques, and some promising applications.