TECH4IMAGING LLC — Department of Energy SBIR Phase I: 10c

Description

Solid mass flow rate is a critical parameter of Circulating Fluidized Bed combustors that are deployed in many energy generation processes. Available devices that can accurately measure the mass flow rate are very limited. Next generation power systems require such measurements for greater flexibility in their operations, and for meeting the higher efficiency and lower emissions conditions. In this proposed effort, we will establish the feasibility of an Adaptive Electrical Capacitance Volume Tomography (AECVT) system for mass-flow gauging of solids circulating at high temperatures. The intrinsic high measuring speed of capacitance measuring technology and high resolution capability of AECVT technology will enable such mass flow measurements at 5% spatial resolution and 1 Hz temporal resolution. In AECVT, the number of independent capacitance measurements is increased through reconfigurable synthetic plates that maintain the minimum area requirement of plates in a capacitance sensor. Adaptive plates are composed of many small segments, each activated by a different level of excitation voltage. The total area of the segments combined is equivalent (or close) to that of a conventional ECVT plate. However, the voltage patterns introduced to the adaptive plate through different segment excitations are able to form new independent capacitance sensitivity measurements. Simulation and measurement results will be used to verify the AECVT system proposed here. In advanced power generation technologies that rely on solid circulation for combustion (i.e. Chemical Lopping), online monitoring of mass-flow rate, flow progression, and distribution is essential. Successful completion of this Phase I will establish the groundwork for full development of an AECVT system for hot temperatures in harsh conditions reactors by the end of Phase II. The work planed in Phase I is structured to adequately match the requested funds. A logical progression from Phase I to Phase II is devised in which Phase I efforts are focused on simulating capacitance sensors at various arrangements of excitation voltage and flow variables, ensuring soundness of the approach, and on developing measuring circuits for this adaptive technique. Phase II tasks will be planned toward a full realization of an AECVT system for hot flow applications in Circulating Fluidized Bed combustors. Successful completion of this project will also result in significant public benefit due to the potential of this technology in helping the energy industry increase efficiencies and lower emissions. The proposed system would also advance multi-phase flow research. It also has a very high potential of attracting commercial interests as the need for advanced instrumentation is imminent.