Industrial flow meters measure the movement of gas or liquid through pipes and ducts. In environmental equipment, flow measurement supports process monitoring, chemical dosing, scrubber operation, wastewater treatment and verification of air or gas movement through VOC-control systems.
PollutionCtrl supplies and sources gas, air, water and wastewater flow meters according to the application. There is no single flow-meter technology for every medium. Selection depends on fluid properties, flow range, pipe or duct size, temperature, pressure, conductivity, solids content, accuracy requirement and installation conditions.
Flow Meters for Air and VOC Exhaust
Industrial air and gas flow measurement may be required in exhaust ducts, ventilation lines, process-gas pipes and treatment-system inlets or outlets. Depending on the conditions, thermal-mass, differential-pressure, vortex, ultrasonic or other flow technologies may be considered.
- VOC exhaust duct airflow monitoring
- RTO and RCO inlet or outlet gas-flow measurement
- Fan and blower performance monitoring
- Combustion-air and process-air measurement
- Compressed-air and selected process-gas applications
- Odor-control and ventilation-system monitoring
Flow Meters for Scrubber and Wastewater Lines
Liquid flow meters may be installed on scrubber circulation water, make-up water, chemical-dosing lines, cooling loops and wastewater pipes. Electromagnetic flow meters are commonly considered for conductive liquids, while ultrasonic, vortex, turbine or other technologies may be appropriate under different process conditions.
- Wet-scrubber circulation and make-up water
- Wastewater-treatment inlet and outlet lines
- Process-water and cooling-water monitoring
- Chemical solution and dosing-system measurement
- Pump discharge and treatment-skid flow monitoring
- Industrial water-reuse systems
Electromagnetic Flow Meter Selection
An electromagnetic flow meter measures conductive liquid without a moving obstruction in the flow path. The liquid conductivity, liner and electrode compatibility, pipe fullness and grounding arrangement must be checked. It is not normally selected for non-conductive oils or gases.
Gas and Air Flow Meter Selection
For gas or air, provide the gas composition, normal and maximum flow, pressure, temperature, pipe or duct dimensions and whether the required value is actual or standardized flow. Moisture, dust, condensate and changing gas composition can influence technology selection and measurement performance.
Output and Communication
Depending on the instrument, available outputs may include 4–20 mA, pulse, frequency, alarm contacts or RS485/Modbus communication. Local displays, remote converters and totalizers may also be available. Compatibility must be confirmed with the PLC, data logger or plant-control system.
Information Required for a Flow Meter Quotation
- Measured gas or liquid and composition
- Normal, minimum and maximum flow
- Pipe size, duct dimensions or connection standard
- Operating temperature and pressure
- Conductivity, solids, moisture or corrosive components
- Required accuracy and turndown
- Display, totalizer and output requirements
- Power supply and communication protocol
- Installation length and available straight-run information
- Quantity and installation location
Frequently Asked Questions
Can one flow meter measure both gas and water?
Usually not. Gas and liquid measurement require different sizing and often different sensor technologies. Each instrument should be selected for the specific medium and operating conditions.
What information is most important for sizing?
The medium, flow range, line size, temperature and pressure are essential. Gas applications also require clarification of actual or standard flow conditions.
View our industrial instrumentation range, or contact PollutionCtrl for gas, air, water or wastewater flow-meter selection.