Automated pneumatic conveyance of biomass with parametric optimization.

摘要

As the cost of fossil fuels is rising inversely with their availability, the need for alternative energy is ever pressing. Biomass is currently the leading source of renewable energy according to the U.S. Energy Information Administration. There are multiple avenues of energy conversion, such as biodiesel, combustion, or gasification. One of the hurdles keeping biomass from being utilized further is its inefficiency in transport due to jamming and entanglement. The project seeks to investigate the automation of a pneumatic conveying system to efficiently transport biomass from a ground-level storage container into a biomass reactor. Pneumatic conveying systems consist of four main components: a blower motor, ducting, a cyclone separator, and an arbitrary storage container. Some of the duct segments between the end effector and the cyclone separator are flexible such that the end effector can traverse freely. There are three stepper motors which provide translation of the end effector in the x, y, and z directions. This project seeks to completely automate the transport of the biomass even in cases of surfaces with non-uniform surfaces while still recording and evaluating the energy input to the system. Aside from automating the system, this project will also include optimizing some of the geometric parameters of the first duct section (from initial entry to particle separator). These parameters will be evaluated based upon their electrical current draw to the system and their particle mass flow rate. The ideal system geometry will move the greatest amount of mass in the least amount of time, use the least power (current draw), and avoid clogging. There are essentially two main components to this project as it relates to the optimization of pneumatic conveyance. Automation decreases labor and theoretically decreases time. The second method of optimization is to investigate the relationship between power consumption and system geometry. The effects of introducing a 90° bend were investigated and evaluated. The quantification of the pressure drop across the bend confirmed the hypothesis that the bend radius for all configurations should be increased. In addition, the geometric parameters of the feeding inlet were investigated, with distinct observations and conclusions drawn. An unanticipated phenomenon occurred which suggested a redesign of the end effector is at least warranted, if not necessary. Finally, energy efficiency of the system was quantified in an effort to broaden the scope of relevance to biomass transport and its potential use. The work done within the scope of this project has demonstrated one way, amongst many, to not only control the 3-dimensional path of the end effector, but also to create a system which interacts intelligently with the surface of the biomass. As is often the case in engineering, it has also lent itself to the opportunity for future improvement.