东北寒区奶牛舍屋顶烟囱风机应用效果研究

Experimental Study on Exhaust Air Chimney Fans Used in Cowshed in Cold Region

针对东北寒区自然通风奶牛舍普遍使用的屋顶烟囱通风冬季结冰堵塞严重,导致舍内湿度过大、有害气体难以排出等问题,本文选用屋顶烟囱风机对黑龙江某典型成乳牛舍的通风系统进行了改造,并对冬季最冷时段的应用效果进行了试验研究。结果表明,牛舍采用屋顶烟囱风机后,舍内空气质量明显好于对照舍,CO2、NH3平均浓度较改造前分别降低51%和63%;舍内相对湿度最低可降至89%,温度可维持在5℃以上。风机不同运行工况虽然对舍内空气质量有一定影响,但差异不大,综合考虑延长设备使用寿命、节电等因素,推荐实行每日定时开启和关闭的风机管理模式;使用屋顶烟囱风机配合独立进风口可使舍内获得更优的环境质量,舍内的雾气现象和异味明显减轻,即使舍外温度低于-30℃,屋顶烟囱风机也不存在结冰堵塞现象。

The Chimney ventilation system has been widely used in natural ventilation cowsheds in the China northeast cold region, but the phenomenons of ice jam in chimneys in winter are serious, which lead to high humidity and waste gas in the cowsheds is hardly to be discharged. This article used exhaust air chimneys to reconstructed the ventilation system of the cowshed in a typical cow farm in Heilongjiang province, and discussed the application effect in the coldest time in winter. The results showed that the air conditions inside the cowshed which uses the exhaust air chimneys was better than the cowshed which not. The CO： and NH3 average concentration respectively could reduce 51% and 63% than that before modification. The average relative humidity could drop to 89%. The average temperature was above 5℃. There was few air conditions difference of different working conditions, in order to reduce the use frequency of fans for extending equipment life and saving power, the operational mode that open and close tans regularly every day is more reasonable. Reasonable air inlets is necessary when using the exhaust air chimneys, fog phenomenons and foul smells inside were reduced obviously. There was no ice jam in chimneys when the temperature outside was below -30℃.