Ganesh Maddikeri
B. E., M. Chem. Engg.
| Education Details | ||
Course |
Institute/University |
Year of Passing |
| B. E. Chemical Engineering |
D.Y. Patil college of Engineering and Technology, Kasaba bawada Kolhapur, Maharashtra. | 2006 |
| M. Chem. Engineering | University Institute of Chemical Technology, UICT, Mumbai | 2009 |
Abstract of Masters Thesis:
MICROWAVE ASSISTED DRYING TECHNOLOGY
Microwaves are high-frequency electromagnetic waves propagating between 300 MHz to 300 GHz the corresponding wavelengths range from 1m to 1mm and are composed of magnetic field. However, only specific frequency ranges are permitted for industrial heating and drying applications, i.e. 915 and 2,450 MHz. The conversion efficiency of electricity to dielectric field is only in the order of 50% and the conversion efficiency of microwave energy to heat is about 70%.
In microwave heating, the electric field of the microwaves interacts primarily with water molecules and ions in the material to be dried. The heat generated by microwave is non-uniform and change in properties that alters the volumetric heat generation itself. Microwave drying involve volumetric level any moisture variation within it. Microwaves are usually generated by an electronic device called magnetron, a magnetron emits high frequency radiant energy with centre of positive and negative charges that changes direction billions of times per second. Volumetric heating due to microwaves penetration and reduced processing times makes it an attractive source of heating.
Nowadays combined microwave techniques such as microwave-vacuum drying, microwave-convection, microwave-freeze drying etc are more advantageous when compared with the microwave only drying. In microwave-vacuum drying microwave is passes through the material, which is selectively absorbed by solvent and dissipated as heat. The rate of drying is increased because it is independent of conduction heat transfer mode and reduced processing times and vacuum can reduce thermal stresses and improve colour and texture of dried products over air-dried products makes it an attractive source of heating. Microwave vacuum drying is used effectively for dying of biological products such as fruits and vegetables and different biomaterials such as carrots, potatoes, garlic, mushrooms, strawberries, seafood and honey and pharmaceutical powders such as asirin, paracetamol, hydrochlorothiazide, lactose & maize starch.