Project Description:

Nestle Purina is one of the top manufactures of pet food in the United States, with the Flagstaff, AZ plant producing about 1,000 tons of pet food each day. When the food is done cooking it contains a 35% moisture content. Therefore all of the food produced needs to be properly dried to meet the 11.5% moisture content requirement. This requirement was set forth to reduce the risk of mold growth due to the build-up of condensation in the bags while cooling. To dry the food, the Flagstaff plant has five steam powered dryers, each responsible for about 20%. However, dryer three is not running as efficient as the other dryers. This dryer should be capable of producing 200 tons per day, but has recently been producing only 150 tons per day, while still using the same amount of energy as the other 4 dryers. The lack of productivity is largely due to the condensation in the steam used for drying the pet food. Because of the large scale of production, this degree of inefficiency costs our client a large amount of money in terms of unmade product. By looking into the heat transfer and thermodynamic properties of this system, we hope to increase the efficiency, throughput, and value of dryer 3 for Nestle Purina.