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Stadem, David

Publications and source records attributed to Stadem, David.

Mitigation of Aerosol Impacts of Ash Deposition and Emissions from Coal Combustion (Final Technical Report)

This project was selected under FOA-0001989 Area of Interest (AOI) 2 – Power Plant Component Improvement. The objective of this AOI was to test and validate technologies and methodologies that can improve the efficiency, reliability, and/or flexibility of individual power plant components in existing plants. The aerosol mitigation technology comprises injection of sorbent into the boiler through injection lances using a positive-pressure blower. The injected sorbent interacts with flame-vaporized aerosolforming components produced during combustion reducing the abundance of sub-micrometer (< 1 micron) particles and fireside ash deposits in the boiler. The primary objective of this project was to validate a sorbent-based technology for mitigating fireside heat transfer surface fouling-related challenges in a full-scale coal-fired power generation facility, thereby, improving plant performance and reliability.

01 COAL, LIGNITE, AND PEAT↗

Long term predictions of coal fired power plant data using evolved recurrent neural networks

Abstract This work presents an investigation into the ability of recurrent neural networks (RNNs) to provide long term predictions of time series data generated by coal fired power plants. While there are numerous studies which have used artificial neural networks (ANNs) to predict coal plant parameters, to the authors’ knowledge these have almost entirely been restricted to predicting values at the next time step, and not farther into the future. Using a novel neuro-evolution strategy called Evolutionary eXploration of Augmenting Memory Models (EXAMM), we evolved RNNs with advanced memory cells to predict per-minute plant parameters and per-hour boiler parameters up to 8 hours into the future. These data sets were challenging prediction tasks as they involve spiking behavior in the parameters being predicted. While the evolved RNNs were able to successfully predict the spikes in the hourly data they did not perform very well in accurately predicting their severity. The per-minute data proved even more challenging as medium range predictions miscalculated the beginning and ending of spikes, and longer range predictions reverted to long term trends and ignored the spikes entirely. We hope this initial study will motivate further study into this highly challenging prediction problem. The use of fuel properties data generated by a new Coal Tracker Optimization (CTO) program was also investigated and this work shows that their use improved predictive ability of the evolved RNNs.

Automation & Control Systems↗