StatusThe thesis was presented on the 12 October, 2007
Approved by NCAA on the 20 December, 2007
Abstract– 0.49 Mb / in romanian
2.24 Mb /
There are presented 32 published scientific works and 2 patents for inventions, there has been carried out theoretical study and research concerning thermic processing of soriz groats such as: swelling, boiling and drying.
There have been determined swelling proprieties of the soriz groats and have been established dependences on pressure, temperature and groats humidity. It has been found out the soriz groats swelling process has to be performed at the pressure of 2,0 MPa and solvent temperature at 60°C. The applying of excessive pressure in soriz groats swelling has intensificated the process in 4,5 times.
There has been carried out research on the kinetics of the soriz boiled groats process by means of convection, microwaves and combined method – SHF. There have been determined kinetics characteristics of the drying process. Experimentally, there has been established the constant of the convective soriz groats K1 and the coefficients of the humidity transfer B were calculated. As a results there has been determined a diffusion resistance in the boiled groats.
This diffusion could be removed by using super high frequency field. The application of the microwaves leads to the intensification of drying process. As a result the coefficient K increases in 10 times (when the maximal nominal power of the magnetron is used).
It has been deduced that soriz – drying by means of power – supply, represented by convection and microwaves has to be performed at the temperature of 80°C, 75 % of magnetron’s nominal power, motivating these conditions by using of reduced consumption of energy and high dried groats quality.
It has been elaborated mathematical model of soriz – drying combined process by means of microwaves applying depending on the length of drying process, temperature, nominal power of magnetron and the humidity content of examined product.
The construction of the industrial soriz – drier based on
swelling, boiling and drying installations has been proposed.
Key words: groats, swelling, drying, convection, microwaves,
temperature, concentrate, quality.