Campus kitchen waste is a typical unit waste. Through the monitoring and analysis of food waste in some colleges and universities, it is found that campus food waste is rich in organic matter. In the solid phase, the fat content is generally 16%, the cellulose and protein content are about 0.9% and 17% respectively, and the reducing sugar content is generally less than 10%. The wave phase component is mainly a mixture of water and waste oil. Compared with other wastes, campus kitchen waste has the following characteristics:

(1) The water content is high, generally 70% - 95%, which is harmful to subsequent treatment;

(2) There are a large number of perishable organic substances, of which organic substances account for more than 90% of the solid phase components. These organic substances are breeding places for various pathogenic microorganisms and pathogenic microorganisms, which are easy to cause disease transmission; The research shows that the total number of bacteria in the food waste placed in the natural state for 24 hours can reach 108/g.

(3) The oil (1%~3%) and salt content are high (0.8%~1.5%). The oil is mainly composed of floating oil, dispersed oil, emulsified oil and dissolved oil. The first three oils can be removed by mechanical separation, while the dissolved oil is dispersed in water in molecular state, forming a uniform system with water, which is difficult to separate. Sodium content is about 0.79%~0.99%, lower than 1.8% toxic to livestock and poultry, and can be used as feed chemicals;

(4) Rich in nutritional value, containing a large amount of starch, cellulose, protein, lipids and a small amount of hydrogen, phosphorus, potassium, calcium, sodium, magnesium, iron and other trace elements, which can be used as animal feed;

(5) The ingredients are relatively simple, and the content of toxic and harmful substances (such as heavy metals) is less.

Food waste treatment According to the composition characteristics of food waste and the existing process analysis, Food waste treatment equipment Their sources should be minimized. There are a lot of existing technology and process research, as well as many mature processes. The scaling treatment process of food waste is mainly subject to the pretreatment process after product preparation and export problems. Therefore, we think it is necessary to select appropriate follow-up processes in combination with the characteristics of catering kitchen waste, so as to solve the problem of campus catering kitchen waste.