Design and development of a natural convection rotary dryer for paddy | |
| Author | Yongyuth Puechkamutr |
| Call Number | AIT Thesis no.AE-85-18 |
| Subject(s) | Rice--Drying Agricultural machinery--Design and construction |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | A new type of rotary dryer f or paddy operating on the principle of natural convection was designer a and developed. A finned-pipe heat exchanger was used to transfer heat from rice- husk fired furnace to the surrounding air and rotating perforated cylinder. The paddy was moved along the spiral flight fixed at the inside surface of the outer cylinder. The operational characteristics of dryer and rice-husk fired furnace were studies and their effectiveness for drying high moisture paddy was evaluated. The grain residence time varied from 30 to 70 second depending upon the cylinder rotation speed, moisture content and feed rate. The throughput capacity ranged from 15 to 50 kg/min. The tempering of paddy for 1 hour after each drying pass resulted in best performance. Normally 3 to 6 passes were required for paddy to safe moisture level. the average moisture reduction in each pass ranged from 1.5 to 3.0 percent wet basis. The moisture removal from paddy during drying and tempering process could be best represented by simple exponential model. Results showed that the drying constant was strongly correlated with the cylinder rotation speed and heat exchanger surface temperature. The milling quality of paddy dried with the experimental dryer comparable to the quality of shade dried paddy in terms of milling recovery and head rice yield. The cost analysis showed that the experimental rotary dryer could prove to be economical than the flat bed type dryers for on farm use. |
| Year | 1985 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Jindal, Vinod Kumar |
| Examination Committee(s) | Illangantileke, Sarath G. ;Gupta, Chandra P. |
| Scholarship Donor(s) | United states of America/ASEAN |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1985 |