Keywords: 
• intermittent wetting /
• Cr /
• As /
• release /
• cement kiln co-processing product

Abstract: The study on influence of intermittent wetting on the release of heavy metals in product from co-processing waste in cement kiln is important for environmental safety assessment of cement product under practical scenarios. Clinker contained Cr and As was produced by simulating cement calcination test，and concrete samples were also prepared. The dissolution characteristic of Cr and As in concretes was researched by the pH-dependence test, and the influence of intermittent wetting on the release of Cr and As in concrete samples was also studied via diffusion test. The results showed that leachant pH of intermittent wetting with carbonation control was in the range of 9.5 to10.4, which was lower than that in continuous leaching control (10.3～11.0). pH of continuous leaching control was close to intermittent wetting with non-carbonation control. Leaching amount of Cr was greater when pH was low or high, and when pH was 5, the leaching amount was minimum (about 5 μg/L). As to As, the leaching amount was higher in low pH, and increasing with the pH descended and reached the minimum at pH=5.As pH>5, leaching amount increased with pH increasing and arrived to the maximum at pH=9 (about 3 067 μg/L). The release amount of Cr and As in intermittent wetting both were lower than continuous leaching, but the release of Cr was restrained by the carbonation in intermittent wetting, while the release of As was promoted by carbonation.