| Systematic study was carried out of Bulk Curing Barn's thermal efficiency, curing environment, cost of construction and Economic Benefit under different configurations, which taken the theoretical results of Bulk Curing Barn's heat-supply system as the reference. And the production demonstration test was also carried out to verify the test results.Its main conclusion is as follows:1. The maximum heat demand of middle size Bulk Curing Barn with loading room of 6m long was 284595.3 kJ/h on the condition that the loading density was 55-65 kg/m3. As to the loose coal stove,the area of its grate should be reached 0.44-0.63m2, the volume of its furnace should be reached 0.36-0.47m3. The heat radiating area of heat exchanger should be reached 8.0-8.7 m2 when the metal materials be used while the area should be reached 9.5-10.4 m2 when the nonmetallic material be used.2. The vertical stove and the honeycomb briquette stove can keep in a stabilized temperature over 15h by once coal filling,and the labor intensity was lower for the coal filling times drop to 6-9 one curing. The combustion intensity of the coal that in honeycomb briquette stove was agree well with the law of heat need . So the control of temperature and humidity was much easyer, the temperature control precision was±1.5℃,and the precision of humidity was±0.3℃. Compared with the horizontal-type stove, honeycomb briquette stove's coal consumed was fewer, per 1000g drying tobacco decreased by 0.19kg, the proportion of high class leaf was improved by 4.8% and the average price was increased by 0.08 yuan/ kg. While the vertical stove's coal consumption was fewest, per 1000g drying tobacco decreased by 0.19kg compared with the horizontal-type stove, the proportion of high class leaf was improved by3.4%. compared with the honeycomb briquette stove, the vertical stove had more extensive range of fuel and better adaptability.3. The radiating effect of heat interchanger with metal materials or steel pipe was the best ,the one with refractory was in the second place,and the one with soil tile was the poorest. The two ends temperature difference of changers between"N"type ,"S"type and"S"type were different."N"type and"S"type were little while"三"type was great. The uniformity of temperature and the air speed in"N"and"S"types changers were better than the"三"type's. the speed of air in"三"and"S"types'room of loading tobacco leaf were bigger than the"N" type's, so the fan or the motor should be bigger while using"N"type heating changer. The effect of heating equipment with different structure was different , someone had a favourable effect,such as the next 4 kinds: vertical stove and"S"type steel pipe changers, vertical stove and"S"type refractory changers, honeycomb briquette stove and"S"type steel pipe changers, honeycomb briquette stove and"S"type refractory changers. The bulk curing barns with heating equipments of these structure had much better curing effect. The coal consumption of per 1000g drying tobacco was in the scope of 1.37-1.43 kg,and the electricity consumption of per 1000g drying tobacco was in the scope of 0.45-0.47kwh.The proportion of high class leaf was over 46% , the average price of per 1000g drying tobacco was over 10 yuan/kg and the cost was lower than 1 yuan. As the medium bulk curing barn with vertical iron stove and metal materials changers, its furnace volume was 0.007 m3 per 1m3 loading room and 0.37 m3 in total, the inlet air area was 0.03m2 per 1m2 loading room and 0.486m2 in total and the heat radiating area of changer was 0.5 m2 and 8.10m2 in total in order to meet the need. But the medium bulk curing barn with vertical brick stove and refractory changers, the furnace volume was 0.008 m3 per 1m3 loading room and 0.43 m3 in total, the inlet air area was 0.035m2 per 1m2 loading room and 0.567m2 in total, and the heat radiating area of changer was 0.60 m2 and 9.72m2 in total in order to meet the need. The test results were match with the results by computing .4. The heat loss of heating room'enclosure structure was higher, decreased the heat loss of heating room'enclosure structure was the key to decrease the heat loss of bulk curing barn's enclosure structure. The thermal insulation performance of 180mm thickness of body wall was poor, the heat loss of all the walls was above 1500 MJ(the lost was bigger) in curing stage but 240mm thickness of body wall was better and the heat loss of all the walls was under 1000 MJ (the lost was smaller)in curing stage. the heat loss of all the walls can be under 800MJ ,the insulation effect would be better and the thermal efficiency would be improved if the fine perlite was used.5. Study on the production demonstration test of bulk curing barn(with honeycomb briquette stove or vertical stove,"S"type steel pipe changers or"S"type refractory changers), the results showed that the effective tobacco production of bulk curing barn was 2124 kg/ha increased by116 kg/ha compared with traditional flue-curing barn, the proportion of high class leaf was 45.68% , increased by 7.78% compared with traditional flue-curing barn, the average price of per 1000g drying tobacco was 9.71yuan/kg , increased by 0.70 yuan/kg compared with traditional flue-curing Barn. The electricity consumption of per 1000g drying tobacco was 0.48 kwh increased by0.48 kwh compared with traditional flue-curing barn, the coal consumption of per 1000g drying tobacco was1.46 kg reduced 0.54kg compared with traditional flue-curing barn, the work amount of per hectare was 28 Reduced 95 compared with traditional flue-curing barn. The bulk curing barn could increased the production of cured tobacco leaves, improve the proportion of high class leaf, reduce the energy consumption and labor, and economic characters were increased obviously.
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