Incinerator slag formation and control of excursion temperatures.
An evaluation of slag formation was initiated to reduce incinerator slag. A factorial test was used to determine the effect of polymers, primary/secondary sludge ratio, and dewatering equipment on ash fusion temperatures (ASTM D-1857). None of the parameters affected the initial deformation or softening temperatures, 1141 and 1181 degrees C, respectively. Incinerators experience slag formation several hundred degrees lower than the measured ash fusion temperature test results. A new test was developed to determine ash fusion temperature. More than seventy 5-cm ash cubes were formed and heated in sets to temperatures of 816, 871, 899, 927, 954, 982, 1038, and 1093 degrees C. The compressive strength of each cube was measured to determine at what temperature fusion begins. A water spray system was built to control excursion temperatures and slag formation. Supplemental water for cooling excursion temperatures requires approximately 4 times less mass than air. Water injected to the incinerator condenses in the wet scrubber, therefore, there is no additional mass load to the incinerator fan. This process study defined the effect of temperature on slag formation.
Greenwood
Stephen
S
Metropolitan Council, St. Paul, Minnesota, USA. steve.greenwood@metc.state.mn.us
Geisenhoff
Jack
J
D017745:Incineration / Q000379:methods*; D007220:Industrial Waste / Q000032:analysis*; D011108:Polymers / Q000737:chemistry; D012722:Sewage / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
D007220:Industrial Waste; D011108:Polymers; D012722:Sewage; D014867:Water