Agricultural Irrigation Pump Selection: Equipment Recommendations for Different Scenarios of Field and Greenhouse
In agricultural production, irrigation is a key link to ensure the healthy growth of crops, and water pumps are the core equipment of the irrigation system. Different agricultural scenarios, such as fields and greenhouses, have significant differences in their requirements for water pumps. Reasonable selection can not only improve irrigation efficiency and reduce energy consumption but also extend the service life of equipment and save costs. This article will deeply discuss the key points of selecting agricultural irrigation pumps, provide professional equipment recommendations for field and greenhouse scenarios, and cover common needs such as “irrigation pump flow calculation” and “corrosion resistance requirements”.
I. Calculation of Irrigation Pump Flow
Accurately calculating the flow of the irrigation pump is the basis for selection. The determination of flow needs to consider multiple factors comprehensively:
- Farmland Area and Crop Water Requirement: Different crops have different water requirements at different growth stages. For example, in high-temperature summer, the daily water requirement of corn is about 2-3 liters per square meter, while that of vegetables may be higher. First, calculate the daily water requirement of crops per unit area, then multiply it by the total area of the farmland to get the total daily water requirement. Suppose a 1000-square-meter cornfield has a daily water requirement of 2.5 liters per square meter; the total daily water requirement is 1000 × 2.5 = 2500 liters.
- Irrigation Cycle: Considering the water supply and actual operational convenience, irrigation is not carried out every day. If the irrigation cycle is 3 days, the total water requirement of the above-mentioned cornfield every 3 days is 2500 × 3 = 7500 liters.
- Pump Working Time: Pumps cannot work continuously for 24 hours. Assuming it works 8 hours a day (the specific working time is adjusted according to the actual situation), the required flow per hour is 7500 ÷ 8 = 937.5 liters, which is converted to cubic meters per hour (1 cubic meter = 1000 liters), that is, 0.9375 cubic meters per hour. In actual selection, a certain margin should be considered to deal with emergencies, and the flow can be increased to 1-1.2 cubic meters per hour.
The calculation formula can be summarized as: Pump flow (cubic meters per hour) = (Farmland area × Daily water requirement per unit area of crops × Irrigation cycle) ÷ Daily working hours of the pump × (1.1-1.2) (margin coefficient)
II. Corrosion Resistance Requirements
The water quality for agricultural irrigation is complex, which may contain sediment, chemical fertilizers, pesticides, acid-base substances, etc., posing a challenge to the corrosion resistance of water pumps.
- Water Source Type and Corrosion Analysis: If the water source is river water or lake water, it may contain sediment, which will wear pump components after long-term use; if treated sewage is used for irrigation, chemical substances in the water may be corrosive; in some saline-alkali areas, the salinity of irrigation water is high, so the requirements for pump materials are more stringent.
- Selection of Corrosion-Resistant Materials:
- Stainless Steel: It has good corrosion resistance and is suitable for irrigation water containing acid-base substances, chemical fertilizer and pesticide residues. For example, 304 stainless steel can resist general acid-base corrosion, while 316L stainless steel has stronger corrosion resistance and can be used in highly corrosive environments.
- Engineering Plastics: Some engineering plastics such as polypropylene (PP) and polyvinyl chloride (PVC) have good corrosion resistance, light weight and relatively low price. However, their strength may be inferior to metal materials, so they are suitable for small irrigation systems or environments with low corrosion.
- Cast Iron: Although economical, it has poor corrosion resistance and generally needs special anti-corrosion treatment, such as coating anti-corrosion paint. In areas with good water quality and weak corrosion, cast iron pumps with anti-corrosion treatment can be selected.
III. Recommendations for Field Irrigation Pumps
Fields are vast, requiring high pump flow, and also need to consider terrain and water source conditions.
- Centrifugal Pumps:
- Features: Centrifugal pumps have the characteristics of large flow and a wide range of lift, with a simple structure and convenient maintenance. Through the high-speed rotation of the impeller, water is thrown out by centrifugal force to achieve water pumping.
- Applicable Scenarios: Suitable for field irrigation in plain areas. When the water level of the water source changes little and water needs to be transported to a long distance, centrifugal pumps perform well. For example, in large-scale wheat and rice growing areas, centrifugal pumps with a flow rate of 50-200 cubic meters per hour and a lift of 10-50 meters can be selected. Like the ISW horizontal centrifugal pump, it has a wide flow range and can meet the irrigation needs of fields of different scales.
- Axial Flow Pumps:
- Features: Axial flow pumps have large flow and low lift, and water flows along the pump axis. They are small in size, light in weight and high in efficiency.
- Applicable Scenarios: In flat areas with sufficient water sources and low lift requirements (generally below 10 meters), such as paddy field irrigation in the south, axial flow pumps are ideal choices. For example, in large-scale paddy fields that require large flow and low lift irrigation, axial flow pumps with a flow rate of 200-1000 cubic meters per hour can be selected, such as the KA series axial flow pumps, which can operate stably for a long time at low water levels and efficiently meet the field irrigation needs.
- Mixed Flow Pumps:
- Features: The performance of mixed flow pumps is between that of centrifugal pumps and axial flow pumps. They have large flow and can provide moderate lift. The shape of their impellers and the way water flows enable them to have the advantages of both.
- Applicable Scenarios: Mixed flow pumps are more suitable for fields with slightly undulating terrain and lift requirements between 5-20 meters. For example, in some farmlands in hilly areas, mixed flow pumps with a flow rate of 30-150 cubic meters per hour can be selected, which can adapt to irrigation needs under different terrain conditions, such as the HL series mixed flow pumps, which are widely used in various field irrigation scenarios.
IV. Recommendations for Greenhouse Irrigation Pumps
The greenhouse environment is relatively closed, and irrigation requires more precision, focusing on water quality and pressure stability.
- Submersible Pumps:
- Features: Submersible pumps can work underwater with low noise, which can effectively avoid interference with the greenhouse environment. They have a compact structure, small footprint, and can directly pump water from deep wells or pools.
- Applicable Scenarios: In greenhouses, if the water source is a deep well or an underground pool, submersible pumps are the first choice. For example, for greenhouses using drip irrigation or micro-sprinkler irrigation systems that require stable water pressure, submersible pumps with small flow but high lift can be selected, such as the QJ series multi-stage deep well submersible pumps, with a flow rate generally of 5-50 cubic meters per hour and a lift of 20-100 meters, which can meet the requirements of greenhouse irrigation for water pressure and water quality.
- Self-Priming Pumps:
- Features: Self-priming pumps have the advantage of no need to fill water before starting, which is convenient to operate. They can automatically discharge the air in the pump body, suck in and transport liquid.
- Applicable Scenarios: When the water level of the greenhouse water source changes greatly or the water source is higher than the pump, self-priming pumps can play an advantage. In some small greenhouses using the “one pump, one pipe” irrigation mode, self-priming pumps with small power and moderate flow can be selected, such as the ZX series self-priming pumps, with a flow rate of 3-30 cubic meters per hour and a lift of 10-50 meters, which are easy to move and use flexibly, meeting the local irrigation needs of greenhouses.
- Corrosion-Resistant Centrifugal Pumps (Stainless Steel):
- Features: Since greenhouse irrigation water may contain corrosive substances such as fertilizers and pesticides, stainless steel corrosion-resistant centrifugal pumps can effectively resist corrosion and ensure long-term stable operation. Their performance is stable, and the flow and lift can be selected according to the greenhouse scale.
- Applicable Scenarios: In large modern greenhouses with automatic irrigation systems, the requirements for pump reliability and corrosion resistance are extremely high. Corrosion-resistant centrifugal pumps with a flow rate of 20-100 cubic meters per hour and a lift of 15-60 meters can be selected, such as the CDL stainless steel light multi-stage centrifugal pumps, which can ensure efficient and stable operation in complex greenhouse irrigation environments and provide precise irrigation services for greenhouse crops.
In conclusion, the selection of agricultural irrigation pumps needs to comprehensively consider flow, lift, corrosion resistance and the special needs of different scenarios. Equipping fields and greenhouses with suitable pumps through scientific calculation and reasonable selection is the key to achieving efficient, water-saving and sustainable agricultural irrigation.