Selection of several common sewage treatment flowmeters!
Metering is the eyes of industry, flowmeter is an important part of metering technology, and metering work plays a vital role.
Since flow is a dynamic quantity, the measurement of flow is a complex technology. From the measured fluid, it includes three kinds of fluids with different physical properties, namely gas, liquid and mixed fluid; from the measurement conditions, there are many Taking the metallurgical industry as an example, the liquid used in production - the measurement of water, is divided into different media such as clean ring water, turbid ring water, steel rolling wastewater, smelting wastewater, and domestic wastewater due to different production systems. . For different sewage water quality, the selection and application of flowmeters are also different.
1. Electromagnetic flowmeter
The electromagnetic flowmeter has a series of excellent characteristics, which can solve the problems that other flowmeters are not easy to apply, such as the measurement of dirty flow and corrosive flow.
In the 1970s and 1980s, there was a major breakthrough in electromagnetic flow technology, making it a widely used type of flowmeter, and the percentage of its use in flow meters continued to rise.
The measuring channel is a smooth straight pipe without blockage, and is suitable for measuring liquid-solid two-phase fluids containing solid particles, such as pulp, mud, sewage, etc.
2. Ultrasonic flowmeter
The ultrasonic flowmeter is designed based on the principle that the speed of ultrasonic waves in the flowing medium is equal to the geometric sum of the average flow rate of the measured medium and the speed of the sound wave itself. It also reflects the flow rate by measuring the flow rate. Although the ultrasonic flowmeter only appeared in the 1970s, it is very popular because it can be made into a non-contact type and can be linked with an ultrasonic water level gauge for open flow measurement without causing disturbance and resistance to the fluid.
Ultrasonic flowmeter can be divided into time difference type and Doppler type according to the measurement principle
The time difference ultrasonic flowmeter manufactured using the time difference principle has been widely concerned and used in recent years, and is currently the most used ultrasonic flowmeter in enterprises.
The ultrasonic Doppler flowmeter manufactured by using the Doppler effect is mostly used to measure the medium with certain suspended particles or bubbles. It has certain limitations, but it solves the problem that the time difference ultrasonic flowmeter can only measure a single clear fluid , is also considered to be an ideal instrument for non-contact measurement of two-phase flow.
Summarize:
For the selection of sewage flowmeters, various flowmeters have their own advantages and disadvantages. In the process of sewage treatment, they should be selected according to actual needs.
①The electromagnetic flowmeter has stable measurement, wide application range, and can measure a variety of media, but it is easily disturbed by electromagnetic waves. As the diameter of the pipe increases, its price will become more and more expensive.
②The cost of the ultrasonic flowmeter is relatively low, the measurement accuracy is high, the operation is stable, the installation and maintenance are convenient, and the price will not increase with the increase of the pipe diameter, but it will become more and more expensive due to the increase of the sound path. .