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• Migration of inorganic chlorine in MW thermal processing was explored. • Furnace temperature significantly correlated with inorganic chloride deposition. • Greatest deposition of inorganic chlorine inside the furnace occurred during pyrolysis. Chlorine is a common element in the environment where it mostly exists in an inorganic ionic state that is highly mobile and non-degradable. It is important to investigate the potential release of chlorine into the environment from mineralized waste (MW) for stable landfill reclamation. In this study, inorganic chlorine in the MW migration process was explored during thermal treatment for chlorine pollution control. The temperature and chlorine greatly affected the distribution of inorganic chlorine in the thermally treated products. Below 800 °C, more than 60% of the inorganic chlorine remained in the bottom slag. Above 900 °C, volatilization caused the release of chlorine from the MW and more than 75% of the inorganic chlorine was deposited inside the furnace. The mass of inorganic chlorine deposited in the thermal treatment furnace was significantly correlated with the actual temperature. At 1000 °C, the masses of inorganic chlorine deposited under pyrolysis, incineration, and gasification atmospheres were 7.69, 5.81, and 5.68 mg, respectively. The greatest deposition of inorganic chlorine inside the furnace occurred during pyrolysis. The chlorine migration process must gain more sight during MW thermal processing. [ABSTRACT FROM AUTHOR]

The chloride ion (Cl − ), a very common monatomic anion, has high ecological toxicity at high concentrations because of its non-biodegradability, and can easily migrate from landfill site into the surrounding environment. Four lab-scale landfill simulation reactors were established to investigate Cl − release behavior: the anaerobic landfill mode (R1), the semi-aerobic landfill mode (R2), the anaerobic landfill with leachate re-circulation mode (R3), and the semi-aerobic landfill with leachate re-circulation mode (R4). The landfill operation modes had a great influence on the release of Cl − . In 256 days, the cumulative release amounts of Cl − in the four reactors were 64.52, 132.07, 56.10, and 33.1 g for R1–R4, respectively. Once air enters anaerobic landfill, the leachate Cl − concentration may sharply increase. The highest leachate Cl − concentrations were 6.6 g L −1 in anaerobic reactor and 18 g L −1 in semi-aerobic reactor. However, the leachate re-circulation can maintain the release of Cl − at dynamic equilibrium state. Theoretically, the Cl − release behavior from anaerobic landfill with leachate re-circulation (R3) will be continuous. In contrast, under the other conditions, it can be anticipated to occur once the leachate recirculation stops (R1) or when the landfill encounters air incursion (R2 and R4). The semi-aerobic operation modes had significantly lower COD/Cl and NH 4 -N/Cl ratios than the anaerobic modes. This indicates that the Cl − pollution risk from semi-aerobic modes is lower than that from anaerobic modes. [ABSTRACT FROM AUTHOR]