Abstract: Material sorting at the pretreatment stage of food waste greatly influences the overall treatment process. If the sorting accomplished inappropriately and there are a lot of impurities in the slurry, there will be problems such as serious pipeline wear and high equipment failure rate. Therefore, the better-operating parameter range of the large material sorting machine is explored herein by adjusting the feeding and operating frequencies, making the sorting work more effective. The better operating parameter range can be obtained from the experiment results, that operating frequency of the large material sorting machine is 70 Hz, and the feeding frequency is below 17 Hz. Under this working condition, the current value of the equipment is low and the fluctuation curve is relatively stable. The proportion of organic matter in the sorting material is between 33% and 37%. Compared with other working conditions, the proportion of organic matter is at least 3% lower. Changes in operating conditions have no effect on the composition of the slurry, the sum of organic matter, peel, and bone accounts for more than 98%, and other impurities account for less than 2%.

Key words: food waste；large material sorting；slurry, sorting material ；feeding frequency；operating frequency