Energy Sources Part A-recovery Utilization and Environmental Effects, Vol.41, No.7, 790-801, 2019
Corrosion evaluation of steel slag based on a leaching solution test
Steel slag is alkaline in aqueous solution, and this is a typical feature for solid wastes that contain large amounts of basic oxides. Therefore, this parameter is used for solid waste hazard assessments. Special attention needs to be paid to the chemical parameters of steel slag to improve its comprehensive utilization, disposal, and storage. The corrosiveness of converter slag samples from different steel plants was evaluated according to the method stipulated by the Chinese national standard GB5085.1-007 to identify whether they would be classified as alkaline hazardous waste. The results showed that steel slag leaching solution had a certain corrosivity, and the pH value of the leaching solution increased with a decrease in the particle size of the steel slag and a decrease in temperature. However, the pH value of the short-term and long-term deposited slag leaching solution was not more than the standard limit value, and hence was not a hazardous waste. It was also found that the pH value (12.66 and 12.60) of the leachate of the grounded products of some of the steel slag was close to the pH of saturated Ca(OH)(2) at 16 degrees C. The measured pH value entered the pH range for a hazardous waste because it was obtained from the grinding of slag powder products. It was not in the original state of steel slag commonly produced by the steel slag industry. Therefore, it cannot be said that this pH directly indicated that the steel slag produced by these steel plants is hazardous waste. This study provides an analytical method that can be used as a basis for the safe storage and comprehensive utilization of steel slag.