What Is Spray Irrigation?

Sprinkler irrigation is an irrigation method in which water with a certain pressure is sprayed into the air with the help of pumps and piping systems or by using the drop in natural water sources to form small droplets or form a mist to land on plants and the ground.

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Using machinery and power equipment, the water is sprayed into the air through the nozzle (or nozzle), in the state of raindrops

a. Water-saving: Since spray irrigation can control the amount and uniformity of water spray,

A complete sprinkler irrigation system generally consists of sprinklers, pipe network, header and water source.

1. 
   According to the pressure obtained by the water flow, it can be divided into mechanical pressure type, self-pressure type and water-lifting and energy-saving sprinkler irrigation system;
   According to the form of sprinkler irrigation equipment, it can be divided into pipeline type and unit type sprinkler irrigation system;
   According to the spraying method, it can be divided into fixed spraying and line spraying irrigation systems.

   The sprinkler irrigation system is divided into the following 3 categories according to the degree of movement during the sprinkler irrigation operation.

   Fixed sprinkler irrigation system: Except the sprinkler head, all components are fixed for a long time or during the irrigation season. The main and branch pipes are mostly buried underground, and the sprinkler head is installed on the vertical pipe connected by the branch pipe. The operation is convenient and efficient. It occupies a small amount of land and is also convenient for comprehensive utilization (such as combining fertilization and pesticide spraying) and automatic control of irrigation. However, it requires a large number of pipes and high unit area investment. It is suitable for cash crop areas (such as vegetable growing areas) and high yields that are frequently irrigated Crop area.

   Semi-fixed sprinkler irrigation system: the sprinkler, water pump and dry pipe are fixed, while the branch pipe and sprinkler head can be moved. The moving methods are manual movement, rolling, end-towed by tractor or winch, and intermittently driven by small engines. Mobile power rolling type, winch type, and self-propelled circular and translation type. Its investment is less than fixed sprinkler irrigation system, and sprinkler irrigation efficiency is higher than mobile sprinkler irrigation system. It is often used for field crops.

   Mobile sprinkler irrigation system: In addition to the water source, power machines, water pumps, main pipes, branch pipes, and sprinklers can be moved, so they can be used alternately in different plots during an irrigation season, which improves equipment utilization and saves units. The area investment, but the work efficiency and degree of automation is low. Some of the commonly used types are light and small sprinklers with power machines and water pumps installed on trolleys or hand racks, the sprinklers of which are installed on a light tripod, and connected to the pump through a hose; Some are small sprinkler irrigation machines equipped with water pumps and sprinklers on walking tractors, which are driven by the power output device of the walking tractors; some are double cantilever sprinkler irrigation machines installed on large and medium-sized tractors. Mobile sprinkler irrigation systems are suitable for irrigation Less frequent field crops and small plots. In addition, in areas where conditions permit, self-pressure sprinkler irrigation can also be developed. Its advantage is that it can take advantage of the natural drop in water, without the need for power machines and pumps, simple equipment, convenient operation, and cost low.

   1. Nozzle selection

   When selecting a sprinkler, in addition to its own performance, such as the sprinkler's working pressure, flow rate, range, combined sprinkler strength, and whether the spray fan angle can be adjusted, it must also consider such factors as soil

   With sprinklers with superior performance and reliable quality, the system must also be carefully designed to truly play the role of sprinkler irrigation and achieve the expected results. The design of a sprinkler irrigation system generally includes the following steps:

   The general requirements for the construction and installation of the sprinkler irrigation system are to strictly follow the design. When the design must be modified, the design unit must be approved and approved by the competent authority. When it comes to the construction of related buildings, it should meet the requirements of the current codes, such as "Code for Construction and Acceptance of Water Supply and Drainage Buildings" and "Code for Construction and Acceptance of Underground Waterproof Projects". According to the characteristics of the sprinkler irrigation system, the following issues should be paid attention to during the construction and installation:

   (1) In the existing sprinkler irrigation plots, in addition to protecting the existing sprinkler irrigation as much as possible, special attention should be paid to the disposal of spoil in trenches. Spoiled soil shall be placed in layers, and the pipe shall be backfilled in layers in the reverse order from the excavation to ensure that the soil in the planting layer along the pipeline is consistent with the original soil.

   (2) Drainage devices shall be installed on the main pipe and each branch pipe to facilitate flushing the pipes and prevent freezing in winter. Even in frost-free

   With the development of the economy, the requirements for the level of greening projects are getting higher and higher. At the same time, in order to further solve the problems of water resources, energy shortages and increased labor costs, more and more greening projects use automatic control irrigation systems. common

   Water management is the core of the overall management of sprinkler irrigation systems. After the sprinkler irrigation system is completed, the quality of water management is directly related to whether the sprinkler irrigation system can play its due role. The basic task of water management is to organize the sprinkler irrigation operations reasonably according to the planning and design of the sprinkler irrigation system and the local climate, growth stage, soil moisture, water supply and other conditions to achieve the purpose of improving irrigation efficiency and maintaining optimal growth conditions. Its specific content includes the following aspects.

   Sprinkler irrigation also has certain shortcomings and limitations, mainly in the following aspects;

   Higher investment in sprinkler irrigation

   Compared with ground irrigation, sprinkler irrigation has a higher investment. At present, semi-fixed sprinkler irrigation generally costs 300 to 500 yuan per mu, including 500 to 800 yuan, excluding power transmission and transformation and labor costs. Fixed sprinkler irrigation is even higher, some as high as 1,000 yuan / mu.

   Sprinkler irrigation is greatly affected by wind and air humidity

   When the wind speed is 5.5 to 7.9m / s, that is, the fourth-level wind or higher, it can blow off water droplets, greatly reducing the uniformity of irrigation, and the drift loss will increase. When the air humidity is too low, evaporation loss increases. According to a test conducted by the Southwest Great Plains Research Center in Texas, when the wind speed is less than 4.5m / s (tertiary wind), the evaporation drift loss is less than 10%; when the wind speed increases to 9m / s, the loss reaches 30%. In China, spraying water under the conditions of 30% to 62% relative humidity and 0.24 to 6.39m / s wind speed through unified measurement in eight provinces and cities including Ningxia, Shaanxi, Yunnan, Henan, Hubei, Beijing, Fujian, and Xinjiang. The loss is 7 to 28%.

   Large energy consumption by sprinkler irrigation

   In order to make the sprinkler run and achieve uniform irrigation, a certain pressure must be given to the sprinkler system. Except for the self-pressure sprinkler system, the sprinkler system needs to be pressurized and consumes a certain amount of energy.