Experimental evaluation of firing pulverized coal in a CO2/O2 atmosphere

The project discussed herein was conducted in support of Argonne National Laboratory to evaluate the feasibility of economically producing carbon dioxide by firing pulverized coal in conventional boilers in an atmosphere of recirculated carbon dioxide with added oxygen. The excess carbon dioxide generated would be used to enhance oil recovery. It is anticipated that this process could be used where coal-fired utility boilers are in reasonable proximity to an oil field. The major objective of this project was to obtain sufficient experimental data to identify relative differences between coal-air and coal-CO2-O2 flames. To achieve this objective, Battelle modified one of its existing coal-fired combustion facilities to permit study of the combustion characteristics of pulverized coal in a CO2-O2 atmosphere. This facility was chosen because it simulates many aspects of the coal burning process within large utility boilers and it is of size to be operated economically regarding material and labor costs. The facility and support apparatus were configured to obtain desired data for comparing coal-CO2-O2 flames to coal-air flames. The experimental tasks associated with this project included conducting tests at four different operating conditions regarding the oxidant mixture. The basis upon which flames were compared included characteristics such as furnacemore » operating conditions, combustion process characteristics, flame spectral and flow properties, radiant heat transfer, and stack emissions. In general, the tests were successful in providing data for comparing coal-CO2-O2 firing with coal-air firing. 10 refs., 36 figs., 31 tabs.« less