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In order to evaluate nitrogen and sulfur behavior during carbonization, carbonization experiment with bio-dried sludge was conducted in a horizontal lab-scale reactor and rotary kiln. Bio-dried sludge dried by using fermentation was used as the carbonization material. Carbonization temperature was changed from 573 to 1173K, and the effect of steam introduction on the elements behavior during the carbonization process was revealed. Nitrogen in the bio-dried sludge decomposed linearly with rising treatment temperature, and more than 90% of nitrogen decomposed at the 1173 K temperature. Sulfur in bio-dried sludge decreased slowly with increasing treatment temperature, but the decreasing ratio was insignificant against the carbonization temperature. Around 70 % of sulfur remained in the char after the carbonization at 1173 K. Sulfur behavior was changed when the steam was introduced during the carbonization. Sulfur content in the char was decreased significantly.

Hydrothermal treatments in different treatment conditions using organic wastes with high moisture content, such as sludge and food waste, were conducted, and the ammonia adsorption capabilities of the solid residues produced were evaluated in this experiment. To understand the characteristics of the hydrothermallytreated solid residues, the BET surface areas and functional groups of the residues were measured. The results show that the solid residues had high ammonia adsorption capabilities. In particular, the sludge solid residue achieved a high ammonia adsorption performance of over 30 mg-N/g-sorbent. There is a strong correlation between BET surface area and ammonia adsorption capability, but the correlation was different according to the waste substance. The solid residue from sludge had higher ammonia adsorption than the residue from dog food. However, the ammonia adsorption change due to BET surface area change was much higher for the dog food residue than for the sludge residue because the dog food residue contained many hydrophilic groups on the surface.

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