The energy intensity of the briquetting process in terms of profitability of waste treatment

V. Liška

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague 6 – Suchdol, Czech Republic
E-mail: vliska@tf.czu.cz

Abstract:

Modern agricultural industry is a source of a considerable amount of waste, which can come in various forms and states. Such waste, and not just agricultural waste in the form biomass, is highly desirable for further processing, depositing or utilising its energy potential. Briquetting technology is suitable for all these purposes. The briquetting press for industrial use is complex technical equipment. The economy of its operation has a major impact on the profitability of the produced briquettes and hence on the efficiency of waste and biomass processing as such. The paper deals with the energy demands of briquetting in terms of waste treatment and economic profitability of production in the whole context of waste processing as a whole.

Key words:

Effect of rake angle and cutting speed on energy demands of mulcher with vertical axis of rotation

J. Čedík¹*, M. Pexa¹ and R. Pražan²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamýcká 129, CZ165 21, Prague 6, Czech Republic
²Research Institute of Agriculture Engineering, Drnovská 507, CZ161 01, Prague 6, Czech Republic
*Correspondence: cedikj@tf.czu.cz

Abstract:

The contribution deals with the reduction of agriculture energy demands. For maintenance and treatment of permanent grassland areas, areas left fallow and put to rest the mulching in combination with other workflows (mowing, grazing) is advantageous procedure. As conventional impact grass cutting and chopping is energy demanding procedure, it is proper to reduce the energy demands of such device. In the paper the effect of shape of cutting tool, particularly the rake angle, on energy demands of mulcher with vertical axis of rotation is studied. The effect of cutting speed on energy demands is also verified. The measurement was performed using mulcher MZ 6000 made by Bednar FMT Ltd. with working width of 6 m and three rotors. During the measurement the test rides using the cutting tools with different rake angle and cutting speeds of 105m s^-1, 89 m s^-1 and 79 m s^-1 were performed. The rake angle of cutting tools were chosen 0°, 15° and 25°. The test area was pasture with permanent grassland. During the measurement the torque and power, transferred through PTO to the machine, fuel consumption and GPS coordinates were measured. From each test ride the samples of grass matter were taken in order to determine the yield and moisture content. It was found that increase of the rake angle up to 25° and decrease of the cutting speed resulted in decrease of the power requirement of the mulcher.

Key words:

cutting speed, cutting tool, energy demands, mulcher, permanent grassland, rake angle