Waste feed is the grease trap waste collected from restaurants and food processing establishments. Typically, it contains a high water content (over 90%), as well as some oil and grease and other food debris.

Grease traps are installed at restaurants and food processing establishments to separate the cooking oils and animal fats from sewage flow because oil and grease will clog sewers and affect the treatment processes of sewage treatment plants. The oil and grease intercepted by grease traps, usually known as grease trap waste, are removed regularly in order to ensure the proper functioning of the grease traps.