A packaged meat production company in the Midwest made a decision four years ago to switch from two separation machines to one that could do the work of two in its wastewater treatment plant. The new machine, along with its other operations, allowed the facility to have zero waste from the 16,000 animals that are processed each day at the plant.  Every head of hog has excess fat. First, the useable meat (for example, ham, sausage, pork bellies and tenderloin) is harvested and sold to the consumer for human consumption and for other purposes such as pet food, industrial, medical and biodiesel.  The leftover parts that are not for human consumption — like the fat, the skin and other parts of the animal — are all used. Therefore, nothing is wasted and nothing goes to landfill. The bones are ground into bone meal. The skin and parts of the head are ground into protein meal, which is a primary ingredient in pet food. Some plants will cook the remaining organic material and use dissolved air flotation (DAF) systems to float the fats, oils and grease to the surface of a pool. This would then be taken to neighboring farms and spread on soil for fertility, which is good for earthworms an...