Research, experiments and surveys on the flat bed dryer, focus on the cracks rice grains, and compare air reversal mode. The results show that, in both attack-8 scale production dryer and dryer in the laboratory 20 kg, the effects of air is reversed clearly to reduce the difference between the final moisture content, however, its effect on drying time or drying rate is not statistically significant. Mechanical drying, whether with or without reverse air, is superior to dry in the sun cracks down on rice. However, in comparison polished controlled drying, drying (with or without air reversal) has reduced rice recovery and growth of cracks, the factors. | Section 2 Study on the flat-bed dryer in the Mekong River Delta of Viet nam 17 Section 2. Study on the flat-bed dryer in the Mekong River Delta of Viet nam ABSTRACT The study including experiments and survey on the flat-bed dryer focused on the cracking of paddy grains and on comparing the air reversal mode. Results showed that in both the 8-ton production-scale dryer and the 20-kg laboratory dryer the effect of air reversal was very apparent in reducing the final moisture differential however its effect on the drying time or the drying rate was not statistically significant. Mechanical drying whether with or without air reversal was superior to sun drying in terms of reducing rice crack. However compared to shade control drying drying with or without air reversal did decrease the head rice recovery and increase the crack the causing factor was not apparent most suspected reason was the drying rate. The decrease in head rice recovery was inconsistent slightly lower or higher in each specific pair of experiments with and without air reversal this was not expected in line with data on the final moisture differential. Testing of a 4-ton dryer at Long-An equipped with the solar collector as supplementary heat source resulted with good grain quality and confirmed the good economic potential. Major findings from the survey on the current status on the use of flat-bed dryers in 7 Provinces were The trend for increased drying capacity the role of local manufacturers and local extension workers government support with interest reduction for dryer loans the drying during the dry-season harvest and especially the unbalance between drying costs and drying benefits. INTRODUCTION Flat-bed dryers have been with the rice agriculture of the Mekong Delta of Viet Nam for a long time. From the first flat-bed dryers in the 1980 s to about 6500 units in 2007 is quite a good progress. But not all is optimistic. Acceptance varies among provinces even among districts or communes in the .
