To understand the behavior and performance of a new 100 kW pilot scale pressurized oxy-coal reactor, radiation measurements of the flame have been made using a Fourier Transform Infrared (FTIR) spectrometer. From these radiation measurements, gas temperatures were obtained using integrated spectral infrared (ISIR) emission from the CO2 and water vapor of the combustion product gases. Radiative emission from the product gases in the reactor were collected through a quartz window 1.524 m downstream of the burner. An optical probe focused culminated emission from the combustion chamber into a silica fiber which transported the radiative signal to the spectrometer. The method produced both wall and gas temperatures as well as total integrated intensity. Values for wall temperature ranged from 1150 to 1450K and gas temperatures ranged from 1150 to 1680K. The wall and gas temperature measurement trends were consistent with expected trends with periods of increasing and decreasing fuel flow rates. Temperatures could not be verified by independent measurements, but the absolute uncertainty of the gas temperature was estimated to be +100 and -50 K in the worst case, with the largest source of uncertainty being due to window fouling. These temperature and integrated intensity values were compared to measurements taken using thermocouple and radiometers at the same axial location on the reactor.

Oxy-combustion is a process which removes nitrogen from air prior to combustion in order to produce a high concentration of CO2 in the exhaust. This enables CO2 liquefaction, transport, and storage to greatly reduce CO2 emissions to the atmosphere. Atmospheric oxy-coal combustion has been successfully demonstrated at industrial scales and could be retrofit in existing coal boilers, but thermodynamic efficiencies are low and therefore uneconomical. Pressurized oxy-coal combustion has the potential for higher efficiency and lower cost but requires new technologies related to the coal feed system, the burner, and ash management. This project describes work needed to complete the dry feed pressurized oxy-coal combustor (POC) at BYU. The POC required the software control system (OPTO22) to be completed, a reactor shakedown, and testing of a previously designed burner by recording reactor thermocouple, exhaust concentration, and radiometer measurements. The following has been successfully demonstrated: 1) reactor heat-up with natural gas 2) coal combustion within temperature limits of the reactor 3) slagging that allows ash management.

The need for electric power across the globe is ever increasing, as is the need to produce electricity in a sustainable method that does not emit CO2 into the atmosphere. A proposed technology for efficiently capturing CO2 while producing electricity is pressurized oxy-combustion (POC). The objective of this work is to design, build, and demonstrate a burner for a 20 atmosphere oxy-coal combustor. Additionally, working engineering drawings for the main pressure vessel and floor plan drawings for the main pressure vessel, exhaust, and fuel feed systems were produced. The POC reactor enables the development of three key POC technologies: a coal dry-feed system, a high pressure burner, and an ash management system. This work focuses on the design of a traditional diffusion flame burner and the design of the main reactor. The burner was designed with the intent to elongate the flame and spread heat flux from the reacting fuel over a longer distance to enable low CO2 recycle rates. This was done by matching the velocities of the fuel and oxidizer in the burner to minimize shear between incoming jets in order to delay the mixing of the coal and oxygen for as long as possible. A spreadsheet model was used to calculate the jet velocities and sizes of holes needed in the burner, comprehensive combustion modeling was outsourced to Reaction Engineering International (REI) to predict the performance of burner designs. Using the guidance of the modeling results, a burner design was selected and assembled. The burner consists of a center tube where the primary fuel will flow, two concentric secondary tubes making an inner and an outer annulus, and eight tertiary lances. The burner and reactor are ready to be tested once issues involving the control system are resolved. Measurements that will be taken once testing begins include: axial gas and wall temperature, radiative heat flux, outlet gas temperature, and ash composition.

One of the challenges facing engineers is to provide clean, sustainable, affordable and reliable electricity. One of the major pollutants associated with coal combustion is CO2. A proposed technology for efficiently capturing CO2 while producing electricity is pressurized oxy-combustion (POC). The first objective of this work is to design, build and demonstrate an exhaust system for a 20 atmosphere oxy-coal combustor. The second objective of this work is to design and build mounts for a two-color laser extinction method in the POC. The POC reactor enables the development of three key technologies: a coal dry-feed system, a high pressure burner, and an ash management system. This work focuses on cooling the flue gas by means of a spray quench and heat exchanger; controlling the reactor pressure and removing ash from the flue gas. Designs and models of each component in the exhaust systems are presented. Methods to test and assemble each system are also discussed. The spray quench flow rate was measured as a function of pump pressure. Theoretical models for the required amount of water in the spray quench, the flue gas composition, the length and number of tubes in the heat exchanger, and the cyclone collection efficiency are presented. The combined exhaust system is assembled and ready to be tested once issues involving the control system and burner are resolved.