Water plays an inescapable role in modern manufacturing processes. At a basic level, water is needed to refine raw materials like metal, wood, and plastic into basic manufacturing resources. Once these materials arrive at the manufacturing facility, they are used again to clean, combine and turn them into water for the products we rely on every day.
When water is exposed to different pollutants during the manufacturing process, it becomes wastewater—one of the largest by-products of manufacturing. Before water can be released into natural reservoirs or recycled for other uses, it needs to be rigorously treated.
To significantly reduce costs and improve sustainability, more and more industrial facilities are choosing to treat wastewater on-site and recycle it back into the manufacturing process. To do this, they rely on multi-step wastewater treatment systems to remove harmful bacteria, chemicals, and organic and inorganic compounds from the water. Technologies such as reverse osmosis systems, ultrafiltration systems, vacuum evaporators and filters, paper bed filters, solids bowl centrifuges and flow oil separators can be used to neutralize and remove impurities from water. While these systems can save millions of dollars in wastewater treatment, transportation, and water procurement costs, they still require careful oversight and maintenance to function properly. To maintain the integrity of these systems, industrial manufacturers rely on four additional pieces of equipment to oversee wastewater treatment.
1. Spirit level
As the name implies, these instruments are used to maintain specific liquid or gas levels in pipes, tanks or silos in wastewater treatment systems. Since the disposal tube is usually opaque and inaccessible, it is impossible to determine the amount of liquid or gas from visual cues alone. Instead, system operators rely on level radars, sensors, and transducers to monitor current water levels. Instruments such as radars, sensors and switches are often interfaced with alarms, pumps or controllers to automatically adjust water and gas flow based on incoming data. Continuous gauges are designed to provide consistent measurements, while point gauges only transmit readings when the water level reaches a preset limit, preventing overflow.
2. Flow meter
Flow meters are used to determine the amount of fluid or gas present in a closed pipeline, and the velocity through the associated container. These instruments are often installed in wastewater treatment pipelines and are designed to measure volume and mass on a regular basis. Using this data, operators can monitor flow and mass flow to maintain the safety and functionality of their treatment equipment. Examples of flow meters include variable area meters, mechanical flow meters, magnetic flow meters, thermal flow meters, and pressure-based meters. The data provided by the flow meter is often used to trigger a flow switch, pump or water supply valve.
3. Pressure instrument
This umbrella category includes pressure transmitters, sensors, transducers and gauges. Like flow meters, pressure meters are often installed in pipes, pumps and sumps of wastewater treatment systems. In addition to measuring pressure, some pressure instruments can also measure flow and liquid level, so as to meet the functions of flow meters and pressure meters. Doing so helps industrial facilities maintain safe pressure levels and prevent equipment failure. The type of pressure instrumentation required depends on the test conditions, the accuracy required, and the specific types of contaminants in the wastewater.
4. Water quality monitoring instruments
Water quality monitoring instruments are required for industrial wastewater treatment. Before treated water can be recycled back into the production process or discharged to sewer, it needs to meet national and local clean water quality standards. On-line water quality instruments are installed in wastewater treatment vessels to provide continuous readings at various points in the treatment process. The type of instrumentation required for each stage of processing depends on the test environment and associated systems. For example, a reverse osmosis system is designed to remove total dissolved solids (TDS) from water, so an in-line meter installed in this system should be able to measure TDS.
In addition to in-line meters, industrial facilities often require manual water quality spot checks to provide greater accuracy and quality assurance. These readings can be taken with a portable meter or in a field laboratory using a benchtop meter.
