The Research On Storehouse Mechanical Ventilation Of High Moisture Grain

This paper summarizes the mechanism and influencing factors of grain drying,we focus on large warehouse with the heap of 6m grain,we designed a mechanical ventilation precipitation system,and selects the appropriate ventilation equipment after determining the appropriate airflow rate and computing ventilation resistance on the condition of air way to research series of problems on ventilation precipitation of the deep grain.The results showed:the top moisture is 17.4%and no more than 2%of moisture range when the paddy is placed in the large warehouse with 60m long,24m span and heap height of 6m.Reducing the moisture of high moisture of high moisture paddy in store drying by mechanical ventilation with low temperature and humidity air in autumn and winter of WuHan.Taking the press and the epispastic ventilation technology order and reasonable control of precipitation of different ventilation stage,the moisture of the paddy can be decrease from 16.6%to 14.4%,falling by 2.2%,during almost four months in autumn and winter.The top moisture is 14.9%and the low moisture is 13.4%,moisture range is 1.5%,of the paddy at end of the ventilation precipitation.The temperature is decreased,the highest temperature can be dropped below 20? in half a moth,the lowest temperature is 4? and without any anomaly high temperature phenomenon of the paddy during the ventilation recipitation process.Besides,the fatty acid value and taste evaluated value are unchanged,other indicators no change or changed little except the crack rate increases 1.5%.It costs only$4.03 with 1 ton paddy decrease 1%moisture per year by mechanical ventilation in store drying.It cost the lowest by the mechanical ventilation in store drying by comparison of the precipitation of it with the others(natural drying,combined ventilation system,fuel dryer)in the influence of the stored air temperature,storage temperature,grain temperature,moisture content and quality(head rice yield,husked rice in paddy,moisture,fatty acid value,taste evaluated value)and so on.As follows:the mechanical ventilation in store drying<combined ventilation system<natural drying<fuel dryer.Also,the comprehensive application of the cost is the lowest.As follows:the mechanical ventilation in store drying<combined ventilation system<natural drying<fuel dryer.It is the best on the effect of precipitation and the benefit of economic with the mechanical ventilation in store drying to deal with the high moisture of the paddy.