Rapid Drying of Lucerne Hay by Maceration
Drying is of major importance in haymaking. The dry matter loss associated with drying is about 25% for ﬁne weather conditions and can exceed 40% when rainoccurs. This loss can be minimized by using more eﬃcient conditioning techniques that increase the drying rate and thus reduce the time interval between cutting and baling. Studies in Australia andoverseas have shown that hay drying rates can be increased by using mechanical and chemical conditioning techniques. However, typical ﬁeld drying time still remains 2 ot 3 days in summer and 4 to 8 daysin winter. Hay maceration is a new technology which has the potential to further improve the drying rate. Maceration is achieved by passing the plant material through a set of grooved rolls rotatingat diﬀerent peripheral speeds. Maceration hastens drying because it ruptures the epidermis and inner tissue of leaves and stems allowing greater moisture loss. Using a two roll laboratory macerationunit, experiments were conducted under southeast Queensland weather conditions to identify the factors aﬀecting dry matter losses and drying rate. Upper roll speed and pressure did not aﬀect the dryingrate of macerated hay but signiﬁcantly aﬀected the dry matter loss. Upper roll pressure of “zero” in combination with a speed of 600 rpm yielded the lowest dry matter loss with no signiﬁcantdiﬀerence in the drying time compared with other maceration treatments. Further experiments comparing the drying rates of the unconditioned, mower-conditioned and macerated hay revealed that the drying time ofmacerated hay was 21% shorter than the mower-conditioned and 48% shorter than the unconditioned hay. Because corrugated cylindrical steel for the macerating roll is very expensive, other material forthe macerating roll surface was assessed. The two corrugated steel rolls were modiﬁed by glueing a softer rubberised belting material to them. Experiments were done to evaluate the eﬀect of the...
Leer documento completo
Regístrate para leer el documento completo.