Blood meal is the most heat sensitive material in this library. The protein starts to denature around 60°C and lysine availability drops with it, and that process cannot be reversed: drying a little more slowly can still be recovered, overshooting the temperature cannot. Blood meal therefore only works on a flash airflow line, where the water is taken out in seconds and the material leaves the drying zone before its own temperature reaches the critical point. The process we use works backwards from the material temperature rather than from the hot air: the air can run at 180°C, and as long as the residence time is short enough the material temperature stays near 60°C.
Blood meal is the most heat sensitive material in this library. The protein starts to denature around 60°C and lysine availability drops with it, and that process cannot be reversed: drying a little more slowly can still be recovered, overshooting the temperature cannot. Blood meal therefore only works on a flash airflow line, where the water is taken out in seconds and the material leaves the drying zone before its own temperature reaches the critical point. The process we use works backwards from the material temperature rather than from the hot air: the air can run at 180°C, and as long as the residence time is short enough the material temperature stays near 60°C. The second difficulty is disintegration. Blood meal carries a lot of water and is very sticky, so the inlet bridges easily, and once it bridges no amount of air gets through: the discharge then swings between too much and too little, too dry and too wet. The lumps have to be broken in the feed section. Dust explosion protection and segregated scheduling are the same as for feed.