The food and animal feed industry processes agricultural, forestry and fishery products into food and feed. These processes often also give rise to by-products of varying value, such as animal skins from slaughter or oil cakes from oil production.
Thermal methods used in the processing and handling of food tend to create unpleasant smells and odours (VOC). The production of pet food, in particular, requires very tight control of odour and Dürr LTB Ecopure® RTO regnerative thermal oxidiser technology used in this application is fitted with special sealed valves.
During food baking and smoking processes and the roasting of cocoa and coffee beans, emissions of CO, VOC and NOx (from caffeine) can occur and have to be treated depending on the scale and location of the process. For CO / VOC emissions, Dürr LTB Ecopure® TAR thermal oxidiser or Ecopure® LPX catalytic oxidiser technology can be used.
However, during the coffee roasting process, nitrogen is also liberated from caffeine and other N-compounds in the coffee beans and oxidised to NOx. Hence, for larger scale coffee roasting applications, DeNOx solution, such as Dürr LTB Ecopure® SCR systems, can be used. Alternatively, Dürr LTB Ecopure® RTO technology withwith integrated SNCR (iSNCR) can be used to control the NOx.
Finally, chemicals and gases (e.g. ethylene) used to preserve perishables during transportation and storage must be later removed in a controlled manner to avoid unwanted emissions. Again, this is a suitable application for Dürr LTB catalytic and non-catalytic thermal oxidiser technologies.