Pelletizing

Abstract: Biomass pellets are a suitable fuel type for a wide range of applications, from stoves and central heating systems up to large-scale plants, and with practically complete automation in all these capacities. This handbook, written and edited by experienced professionals from IEA Bioenergy Task 32 in cooperation with Bios Bioenergiesysteme GmbH, Graz, Austria, other IEA Tasks and external experts, is the first comprehensive guide in English language covering all pellet related issues, as illustrated by the following list of topics covered by the book: international overview of standards for pellets evaluation of raw materials and raw material potentials quality and properties of pellets technical evaluation of the pellet production process and logistic aspects of pellet supply safety and health aspects for pellets during storage, handling and transportation technological evaluation of pellet furnace technologies and future developments economic and ecological evaluation of the pellet production process economic and ecological evaluation of pellet use in small-scale furnaces in the residential sector overview of international pellet markets and market developments international case studies for the use of pellets for energy generation latest trends concerning research and development in the pellet sector. Extensively illustrated and packed with practical knowledge, this is the ultimate reference for anyone involved in or affected by this burgeoning industry. It addresses all the players of the pellet market, ranging from raw material producers or suppliers, pellet producers and traders, manufacturers of pellet furnaces and pelletization systems, installers, engineering companies, energy consultants and end users.

Abstract: The depletion of fossil fuels and the need to reduce greenhouse gas emissions has resulted in a strong growth of biomass utilization for heat and power production. Attempts to overcome the poor handling properties of biomass, i.e. its low bulk density and inhomogeneous structure, have resulted in an increasing interest in biomass densification technologies, such as pelletization and briquetting. The global pellet market has developed quickly, and strong growth is expected for the coming years. Due to an increase in demand for biomass, the traditionally used wood residues from sawmills and pulp and paper industry are not sufficient to meet future needs. An extended raw material base consisting of a broad variety of fibrous residues from agriculture and food industries, as well as thermal pre-treatment processes, provides new challenges for the pellet industry. Pellet production has been an established process for several decades, but only in the past five years has there been significant progress made to understand the key factors affecting pelletizing processes. A good understanding about the pelletizing process, especially the processing parameters and their effect on pellet formation and bonding are important for process and product optimization. The present review provides a comprehensive overview of the latest insights into the biomass pelletization processes, such as the forces involved in the pelletizing processes, modeling, bonding, and adhesive mechanisms. Furthermore, thermal pretreatment of the biomass, i.e. torrefaction and other thermal treatment to enhance the fuel properties of biomass pellets are discussed.

Abstract: The majority of iron ores must be ground to a fine particle size to allow the iron oxides they contain to be concentrated, and the concentrate must then be agglomerated back into large enough particles that they can be processed in blast furnaces. The most common agglomeration technique is pelletization, which requires the use of binders to hold the iron oxide grains together so that the agglomerates can be sintered into high-strength pellets. Although bentonite clay is the most commonly used binder, there are many other possibilities that could be competitive in a number of situations. This article reviews the numerous types of binders (both organic and inorganic) that have been considered for iron ore pelletization, including discussion of the binding mechanisms, advantages and limitations of each type, and presentation of actual pelletization results, so that the performance of the various types of binders can be compared and evaluated.