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July 2021 / 31 BIOMASS REVOLUTION — CAN YOU HANDLE IT? Conveying systems are designed to handle specific types of materials. Determining which conveying system is well-suited for your material can be difficult if you don't know much about the material involved. This article describes the importance of under- standing your material – in this case, biomass – in order to determine the best material handling system for the application. Joel E. Dulin, Biomass Engineering & Equipment The firm likely did this because EPC companies typ- ically design and procure production-area equipment first when designing a new manufacturing facility and then use the remaining budget to procure conveyors to tie the production areas together. This often results in the EPC companies sourcing cheap conveying equipment. EPC engineers, and many manufacturers, view material handling as an overhead expense — something that adds cost but isn't as important as processing equipment because it doesn't produce any- thing. The same attitude commonly accompanies waste handling systems (biomass is often process waste from lumber mills): because waste has little — if any — value, companies try to spend as little as possible on systems that handle it. The importance of biomass handling systems comes to the forefront, however, when the system results in downtime or requires excessive attention from maintenance personnel. Regardless of whether these conveyors are handling waste or feedstock, when the conveyors stop, production halts, and any money the manufacturer saved by purchasing inexpensive han- dling systems quickly evaporates. Understanding biomass characteristics Biomass is highly variable and encompasses a great number of materials ranging from corn stover to wood chips, as shown in Figure 1. Despite its variabil- ity, biomass materials share characteristics that affect their handling. Contamination. Unlike factory-made materials, biomass is harvested, the process of which inevitably picks up foreign materials such as rocks, dirt, sand, debris, scrap metal, and the occasional tool. Biomass contamination is so common that the National Fire Protection Agency (NFPA) stipulates in NFPA 664: Standard for the Prevention of Fires and Explosions in Wood Processing and Woodworking Facilities that manufacturers must inspect biomass for foreign materials prior to A s demand for renewable and climate-friendly materials has grown, so has interest in cellu- losic biomass — renewable plant materials such as forest or agricultural wastes. New industries that use biomass have thus emerged, and industries that used it on a small scale in the past have grown signifi- cantly. Examples of such industries include biochar, fuel pellets, and powdered lignin. These industries have grown so rapidly, however, that knowledge about what works and what doesn't work in regard to han- dling large volumes of biomass hasn't disseminated from industries familiar with biomass challenges, such as paper manufacturers and particle board makers. As a result, operations personnel in emerging industries must often determine through trial and error which systems work best for handling biomass materials. To complicate matters, higher standards in safety and performance have outmoded many bulk handling systems on the market. Conveyors that were once good enough despite their drawbacks no longer meet the performance standards expected of them. This change in the market has created a need to identify better biomass handling systems than those that have tradi- tionally been used. Prioritizing material handling systems Companies often de-emphasize bulk solids handling systems when designing a new plant because they often view these systems as ancillary equipment. As a result, operations that use biomass are often equipped with conveyors that aren't robust enough to handle the mate- rial. In worst-case scenarios, biomass operations have failed at startup due to indifference about material han- dling systems. This is what happened at a massive pellet plant in Wawa, ON, when the engineering, procure- ment, and construction (EPC) firm overseeing the build equipped the plant with conveyors undersized for the application. The conveyors were continually overloaded with biomass and never functioned properly.