Research On The Separation Mechanism Of Flotation Column Hydrocyclone

Heilongjiang province is China’s important grain production base, located in China’s northeast cold weather and the per capita amount of water below the national level, the shortage of water resources seriously restrict the development of the industry and agriculture in our province. Especially in the way of agricultural cultivation in China, the utilization rate of water resources is 45% behind many developed countries. The effective use of the existing land resources and water resources is particularly important, water-saving irrigation to improve agricultural yields becomes one of the most important issues of national food security.For the cold zone in northeastern China, the paper observed data in winter field experiment and analyzed the variation of soil moisture and temperature during winter with different straw mulching treatments, the appropriate solution is proposed to prevent spring drought. The results of the analysis of the experimental data are as follows:(1)Straw mulching, as a kind of obstacles to soil and atmospheric heat exchange medium,as some hindrance effect on the heat transfer from soil to the atmosphere and from atmosphere to soil.Under different temperature conditions the direction of heat transport is not consistent, the effect of straw mulch on the adjustment of soil temperature is different. The trend of temperature change of the soil always lags behind the change of the atmosphere temperature. As the surface soil and air contact is relatively close, the effect of the environment change is obvious. With the depth of soil continues to increase heat transfer of consumption and time occupies the proportion gradually become larger, so different straw cover treatment for deep soil temperature effect with soil depth increasing gradually decreases. From this we can see that the soil temperature in the straw mulch treatment is the result of the interaction between the straw mulch amount, soil heat conduction characteristic and soil depth.(2)Through to the definition of soil temperature coefficient calculated and compared the different between plots of differences in soil temperature coefficient. It is found that the bare treatment soil temperature difference coefficient is the largest, and bare land shallow layer soil temperature difference coefficient is about 3 times of that of the bare land of deep soil temperature difference coefficient. In straw mulch treatments, 5cm straw mulch treatment has the maximum soil temperature difference coefficient, followed by 15 cm straw mulch treatment, 10 cm straw mulch treatment has the minimum soil temperature difference coefficient. This showed that the difference coefficient of soil temperature in different mulching treatments did not increase with the increase of thickness. The change of the thickness of straw cover is not monotonic.(3) Straw mulching could delay the liquid moisture content in the 0~60cm layer, with the increase of straw cover thickness, the delay effect is more obvious, but the delayed effect of soil freezing stage was significantly higher than that of frozen soil thawing period; The straw mulching can hinder the thawing of frozen soil, and restrain the soil water evaporation from the end of frozen soil thawing, which has very important significance for soil moisture, With the increase of soil depth, the range of Ka and coefficient of liquid water content variation Cv of each treatment showed a decreasing trend; When soil depth exceeds 100 cm, the change of liquid moisture content in different treatments is little; When the straw mulch was over 10 cm, the change of the liquid moisture content of the soil was very little. Straw mulching can effectively stabilize liquid water content variation in the freezing thawing period in depth of 0 ~ 60 cm, and with the depth increasing its stabilizing effect has a weakening trend. The dual role of snow melt and straw mulching can increase soil moisture effectively. But the ability decreased with the increase of soil depth, the different straw mulching thickness on 0~60cm soil average moisture capacity from big to small order are: 15 cm, 10 cm, 5cm.