| Contents Notes |
"Use of blast furnace blowdown water to quench hot blast furnace slag is a possible alternative to the treatment and disposal of this wastewater. Because this alternative is not without possible detrimental effects on air quality, however, an environmental assessment program was undertaken to evaluate the air emissions arising from quenching blast furnace slag with blowdown water from a blast furnace scrubber wastewater recirculating system. Fifteen test runs were conducted at two different slag temperatures, 1100 and 1500ÀF (593 and 816ÀC). Results of this laboratory-scale assessment of simulated blast furnace slag quenching with mill service (baseline) water versus blast furnace blowdown water indicated that participate emissions increase at a more pronounced rate with high slag temperatures when blowdown water is used, presumably because of its higher total dissolved solids content. The quenched slag was not considered hazardous, based on the extractive procedure (EP) toxicity tests. Although minor quantities of organic pollutants evolve during quenching, the data showed no relationship between these pollutants and slag temperatures, slag characteristics, or water quality. Also, no correlation was found between quench water quality or slag temperature and emissions of sulfur dioxide, ammonia, and fluorides." |
