When choosing an electromagnetic flowmeter for wastewater treatment, the following key factors need to be considered:
1. Measuring flow range
Importance: Make sure that the measuring range of the selected flowmeter can cover the actual flow demand of wastewater treatment. Setting the range too large may result in reduced accuracy, while setting it too small may cause the flowmeter to appear blocked.
Selection method: Select the appropriate flowmeter model and range according to the flow demand of wastewater treatment.
2. Fluid medium characteristics
Conductivity: Electromagnetic flowmeters are suitable for conductive liquids. Wastewater usually has a certain conductivity, but it should be ensured that the conductivity of wastewater is within the specified range (usually greater than 5µS/cm).
Corrosiveness: Wastewater may contain corrosive substances, so corrosion-resistant electrode materials and lining materials should be selected. Commonly used metal materials include molybdenum-containing acid-resistant steel, Hastelloy, etc., which can cover almost all chemical liquids.
Solid content: The solid content in wastewater is also an important consideration. A flowmeter that can handle the corresponding solid content should be selected according to actual conditions.
3. Measurement accuracy
Importance: Measurement accuracy is an important indicator when selecting an electromagnetic flowmeter, which directly affects the accuracy and efficiency of wastewater treatment.
Influencing factors: Measurement accuracy is affected by many factors, such as pipe diameter, pipe length, fluid medium, flow rate, flow range, etc.
Selection method: According to actual needs, select a flowmeter with appropriate accuracy. At the same time, pay attention to avoid reduced accuracy due to improper installation or environmental factors.
4. Working environment
Temperature and pressure: Select a flowmeter suitable for the temperature and pressure range in the wastewater treatment process to ensure the stability of the equipment under extreme conditions.
Protection level: In harsh environments, select an electromagnetic flowmeter with a higher protection level to ensure its long-term stable operation.
5. Other factors
Installation location: The installation location of the flowmeter should avoid pipeline elbows, valves and other flow disturbance devices to ensure measurement accuracy. It is usually recommended to retain 5 to 10 times the straight pipe section before and after the flowmeter.
Signal output: Select a suitable signal output (such as 4 to 20mA, pulse output, Modbus, etc.) according to system requirements to ensure good compatibility with the host computer or monitoring system.
Brand and price: Choose a well-known brand and a reputable manufacturer, and consider the price factor at the same time to choose a cost-effective product.
In summary, when choosing an electromagnetic flowmeter suitable for wastewater treatment, it is necessary to comprehensively consider the measurement flow range, fluid medium characteristics, measurement accuracy, working environment and other factors. Through careful analysis and comparison, select the flowmeter model and specifications that best suit actual needs.