Abstract:Aiming at the problems of long treatment cycle and low water removal efficiency of kitchen waste biological drying, the effects of different heating temperature and heating time (signed as CK, JR 55-30, JR 75-30, JR 95-30, JR 105-20, JR 105-30, JR 105-40, JR 115-30, respectively) on water removal efficiency, energy consumption and nitrogen loss of kitchen waste biological drying, on the biological drying machine with external auxiliary heating. The results showed that: (1) The energy consumption of water removal per unit mass of CK, JR 75-30 and JR 105-30 were 0.58, 1.24 and 1.34 kw.h.kg-1, respectively, which were lower than other treatments (1.337 - 1.613 kw.h.kg-1); (2) The water removal efficiencies of JR 105-30, JR105-40 and JR 115-30 were 84.22%, 92.27% and 84.77%, respectively, which were higher than other treatments (26.86% - 76.82%); (3) The higher the heating temperature and the longer the heating time, the greater the loss rate of TN and ammonium nitrogen; The loss rate of TN was 6.16% - 20.03% and the loss rate of ammonium nitrogen was 19.15% - 60.87% of all treatments. The pearson correlation results show that TN and ammonium nitrogen were positively correlated with moisture content (p<0.05), and negatively correlated with EC (p<0.05). The results showed that the energy consumption of water removal per unit mass of JR 105-40 was 1.52 kw.h.kg-1, which was higher 0.94 kw.h.kg-1 than CK (0.58 kw.h.kg-1); the water removal efficiency was 92.27%, which was higher 65.41% than CK (26.86%); the loss of TN was 19.49%, which was higher 13.33% than CK (6.16%); and the loss of ammonium nitrogen was 57.45%, which was higher 38.30% than CK (19.15%), respectively. On the premise of ensuring the drying efficiency, JR 105-40 is recommended for biological drying of kitchen waste, and can reduce the water content to 28.56% on day 4. The results provide a reference for the selection of external heating temperature and heating time for the treatment of kitchen waste by external auxiliary heating biological drying machine.