HEAT AND MASS EXCHANGE PROCESSES DURING THE DELIGNIIFICATION OF WHEAT STRAW IN THE ROTOR-PULSATION APPARATUS

Abstract

In the production of biofuel in Ukraine, wheat and sunflower are most widely used. The production of bioethanol from lignocellulosic raw materials (wheat straw) has both a number of advantages and disadvantages compared to traditional raw materials containing starch, due to the complex structure of lignocellulosic biomass. A mandatory stage of raw material processing is its preliminary preparation for hydrolysis. One of the tasks of the research is the delignification of wheat straw and the improvement of the efficiency of the preliminary treatment of lignocellulosic raw materials using the physical effects that occur during the movement of a viscous liquid in rotary-pulsation devices. Wheat straw was used as an object for research. The amount of isolated lignin was determined by the weight method. The results of the experimental studies showed that during the processing of the aqueous dispersion of straw in the rotary-pulsation apparatus, it is heated to a temperature at which intensive release of lignin is ensured. The main mechanism of these processes is the dissipation of the kinetic energy of the rotor rotation. It is shown that the use of rotary-pulsation devices for heating raw materials intended for hydrolysis is an effective substitute for external thermal energy sources. It was found that the treatment of aqueous dispersion of straw in a ratio of 1:10 for 70 min. leads to the release of 42 % of lignin. Changing the hydromodulus from 1:10 to 1:5 increases the percentage yield of lignin to 58 %.