For most cultivated crops, low temperature and high humidity, high temperature and high humidity are important causes of disease occurrence and spread. Especially in the winter, the greenhouse outside the greenhouse temperature is low, especially need to strengthen the insulation and ignore the wind and dehumidification leading to gray mold, Diseases such as downy mildew are rampant. Therefore, controlling greenhouse humidity is an important part of greenhouse cultivation technology.
1, ventilation and dehumidification
Ventilation is the most basic method of dehumidification in greenhouses. Ventilation must be carried out at high temperatures, otherwise the temperature inside the shed will drop. Within one day, the best time for ventilation and dehumidification is noon, because the humidity inside and outside the shed is large, and moisture is easier to discharge. At other times, the ventilation time should be extended as much as possible while maintaining the temperature requirements. If the temperature drops too fast during ventilation, close the vents in time to prevent the temperature from dropping suddenly and causing the vegetables to be harmed.
2, using plastic film to cover the damp
The mulching film can reduce the evaporation of surface moisture into the shed, which is an important measure to reduce the humidity of the air in the shed.
3, using dust method, smoke method to apply moisture
By using the dust method and the smoke method, it is possible to avoid increasing the humidity of the air due to the spray and improving the control effect.
4, cultivating dehumidification
By cutting off the soil capillary, soil capillary water can be prevented from rising to the surface layer, and a large amount of evaporation of soil moisture can be avoided.
5, naturally hygroscopic
Spread a layer of straw, wheat straw, quicklime, or a layer of grass ash between the rows to effectively absorb water vapor or fog to achieve the purpose of reducing moisture.
6, heating and cooling
When the temperature in the greenhouse is low, the relative humidity in the room can be lowered by increasing the temperature, and the temperature requirement of the vegetables is also satisfied.
7, reasonable watering and humidity control
Watering is a major factor in the increase in humidity in the shed. In winter and spring, you can choose to ditch in sunny days or water in different parts. Strictly control the amount of water. Appropriate air is released after watering, and the soil is drained in time to reduce the air humidity.
8, increase the amount of light transmission and humidity
Increasing the amount of light transmission can increase the temperature of the shed, and increasing the temperature of the shed can increase the saturation of the air temperature, thereby reducing the relative humidity of the air.
9, using a hygroscopic insulation screen to absorb moisture
A canopy is placed in the shed, and a moisture permeable and hygroscopic insulation material such as a non-woven fabric can prevent condensation on the inner surface and prevent the dew from falling onto the plant, thereby reducing the humidity of the air.
10. In the winter, the vegetable pests and diseases in the greenhouse should be used as much as possible by the smoke method or the dust method. If the spray method is applied, the number of prevention and the amount of liquid spray should be appropriately reduced to prevent the humidity in the shed from being too high.
11, purchase dehumidification equipment
In winter, the greenhouse indoor and outdoor temperature difference is relatively large, it is easy to produce a large number of water drops indoors, how to keep the indoor dry, moderate humidity, keep the crops grow normally and quickly, a dehumidifier is your best choice.
Application
a.textile industry:PVA is mainly used as a warp dressing agent, textile finishing agent and the raw material of vinylon;
b.construction :upholstery industry 107 glue, it's used as an additive of cement and mortar, inner and outer wall paints, and moulding board binder.
c.chemical industry: it's used as a polymer emulsifying agent, dispersing agent and used to produce PVA formal, PVA acetal and PVA butyral.
d.paper industry:It's used as an adhesive in lumbering and paper-making industries.
e. agriculture: used as a soil improving agent, pesticide reinforcing agent and PVOH thin film
f. used as a well-fixing agent in petroleum exploitation.
g. It can also be used into cosmetic, medicine, printing, ceramics, steel-making, electronics and plating.
PVA Resin
HENAN CHUANGE INDUSTRY CO., LTD , https://www.chuangegroup.com