Fundamental mechanisms in flue gas conditioning. Quarterly report, April 1992--June 1992

Abstract

SEM pictures of the three mixtures of sorbent and ash from the DITF and the base line ESP hopper ash from Muskingum are shown in Figures 1 through 4. The effects of sorbent addition on particle morphology are evident in Figures 2 through 4 by the presence of irregularly shaped particles and deposits on the surfaces of the spherical fly ash particles. In contrast, the base Ene ash particles have the characteristic relatively smooth, spherical morphology normally associated with pulverized-coal (PC) fly ashes. Resistivity determinations made on these four ashes in ascending and descending temperature modes. These data are shown in Figures 5 and 6. Sorbent injection processes performed at the DITF lowered the duct temperature to around 165{degrees}F from about 350{degrees}F for base line operation. Consequently, during collection in the ESP, the particulate matter from the sorbent injection processes had a significantly lower resitivity (approximately 4 {times} 10{sup 7} {Omega}-cm) than the base line ash (approximately 3 {times} 10{sup 11} {Omega}-cm at 350{degrees}F). Specific surface areas and true particle densities have been measured for the four samples obtained from the DOE/PETC Duct Injection Test Facility. These data are summarized in Table 4. The primary difference indicated by these initial analyses of these four samples is the significant increase in specific surface area due to sorbent addition. The specific surface areas of the three sorbent and ash mixtures from the DITF are quite similar.