Flow measurement is a critical process in many industrial applications, as it helps to ensure the efficient and safe operation of processes involving liquids and gases. Accurate flow measurement is essential to monitor and control the flow rate of fluids, which is crucial in optimizing the performance of industrial processes. However, measuring the flow of corrosive liquids and gases can pose a significant challenge due to the corrosive properties of these fluids. Corrosive fluids can damage flow measurement equipment and cause measurement inaccuracies, leading to inefficient process operations, reduced equipment lifespan, and potential safety hazards.
Corrosion is a prevalent issue that can occur in flow measurement equipment used to measure corrosive liquids and gases. Corrosion can take various forms, including pitting, crevice corrosion, and galvanic corrosion. Corrosion can affect the measurement accuracy of flow meters by causing wear and tear of the equipment’s internal parts, which can result in a change in the flow measurement. Corrosion can also lead to the equipment’s failure, leading to costly repairs or replacement.
Types of Flow Measurement Techniques for Corrosive Liquids and Gases
There are several types of flow measurement techniques that can be used for corrosive liquids and gases, including:
- Mass flow meters: Mass flow meters measure the mass flow rate of a fluid. They are not affected by changes in fluid density, viscosity, or temperature, making them an ideal choice for measuring corrosive liquids and gases. Mass flow meters can use various techniques such as thermal, coriolis, and differential pressure to measure mass flow.
- Electromagnetic flow meters: Electromagnetic flow meters, also known as mag meters, measure the velocity of a fluid by using a magnetic field. They are not affected by changes in fluid density, making them a good choice for measuring corrosive liquids. However, they can be affected by changes in fluid conductivity, and are not suitable for measuring non-conductive fluids.
- Vortex flow meters: Vortex flow meters measure the frequency of vortices shed by a bluff body inserted into a fluid flow. They are not affected by changes in fluid density, viscosity, or conductivity, making them a good choice for measuring corrosive liquids and gases. However, they can be affected by flow disturbances and may not be suitable for measuring low flow rates.
- Micro motion multiple variable flow transmitter: This flow measurement technique uses Coriolis force to measure mass flow rate and density, and it can also measure temperature and volume flow rate. The use of Coriolis force makes Micro Motion flow meters insensitive to changes in fluid properties such as viscosity, density, and conductivity, making them an ideal choice for measuring corrosive fluids.
- Ultrasonic Flow Meters: The non-invasive design of ultrasonic flow meters makes them suitable for measuring corrosive fluids. The flow measurement instruments use sound waves to determine fluid velocity which reduces the risk of sensor degradation. The ultrasonic meters work best for short-term or mobile flow measurement applications in industrial settings.
- Differential Pressure Flow Meters: The flow measurement methods differential pressure meters provide reliable solutions through devices such as Venturi tubes or orifice plates. The flow measurement instruments need corrosion-resistant linings to effectively handle aggressive fluids. These instruments maintain their position as trusted flow measurement solutions across different applications because of their durable nature.
How to Select Right Flow Measurement Equipment for Corrosive Liquids
Here are some points to consider when selecting flow measurement equipment for corrosive liquids and gases:
- Identify the properties of the fluid: It’s important to identify the properties of the fluid, such as its corrosiveness, viscosity, temperature, pressure, and flow rate. This information will help determine the appropriate flow measurement technique and material.
- Choose the appropriate flow measurement technique: Select a flow measurement technique that is suitable for corrosive liquids and gases. Some examples include mass flow meters, electromagnetic flow meters, and vortex flow meters.
- Consider the material of the flow measurement equipment: Choose a material that is resistant to corrosion and can withstand the properties of the fluid being measured. Common materials include stainless steel, titanium, hastelloy, and tantalum.
- Evaluate the mechanical properties of the material: The mechanical properties of the material should also be considered, such as its strength, ductility, and toughness. The material should be able to withstand the stresses placed on it during operation.
- Ensure compatibility with the fluid: The material should also be compatible with the fluid being measured. This includes ensuring that the material does not react with the fluid, and that it does not contaminate the fluid.
- Consider installation and maintenance requirements: Installation and maintenance requirements should also be considered, such as access for cleaning, calibration, and repair.
- Consult with experts: In complex applications, it may be necessary to consult with experts to determine the appropriate flow measurement equipment. This could include flow measurement specialists, corrosion engineers, or other technical experts.
By selecting the right flow measurement technique and Equipment for corrosive fluids is essential to ensure efficient and safe industrial processes. If you plan to invest in a new and used flow instruments, then make sure you source it from a reliable supplier in the industry like JM Industrial. The company is a global supplier of high-quality surplus and used Industrial instruments including Level Instrument, Pressure Instruments, Temperature Instruments and more.
Frequently Asked Questions (FAQ):
What are the units of flow?
The measurement of flow occurs through volumetric units which include liters per minute (L/min) and cubic meters per hour (m³/h) and mass units like kilograms per hour (kg/h). The standard volumetric units standard cubic feet per minute (SCFM) serve as the primary measurement for gases.
What are the principles of flow measurement?
Flow measurement depends on differential pressure and electromagnetic induction and ultrasonic transit time and Coriolis force and mechanical displacement principles. The different principles enable the measurement of flow rates through various fluid types and applications.
What are three ways that flow can be measured?
The measurement of flow occurs through three methods which include volumetric flow rate and mass flow rate and fluid speed through a pipe. The selection of measurement methods depends on the application requirements and fluid properties and system needs.
What instrument is used to measure flow?
The main flow measurement instruments consist of Coriolis flow meters together with electromagnetic flow meters and vortex flow meters and ultrasonic flow meters and differential pressure transmitters. The selection depends on the fluid characteristics and the required measurement precision.
What are the two ways flow can be measured?
Flow can be measured using contact methods (e.g., turbine or vortex meters that touch the fluid) and non-contact methods (e.g., clamp-on ultrasonic meters that measure from outside the pipe). Both approaches have advantages based on fluid type and installation requirements.
