Much of treated wastewater is “reclaimed” or recycled for other uses like irrigation. These are tricky applications for conventional sensors that require frequent recalibration. For example, in one Orlando, Florida USA wastewater treatment plant, their current sensors (one of our competitor’s units) must be calibrated three times per day (each work shift) to obtain accurate readings. However, Halogen Systems sensors do not require calibration for over one month of operation and read accurately straight out of the box with factory-set calibrations. Calibration remains infrequent with our sensors due to our patented, continuous, self-cleaning system. Our approach to residual chlorine sensors keeps the sensing surface free of organics and other forms of build-up.
Halogen Systems Inc. modified its sensor for wastewater purposes and shipped its first sensor in May of 2021. Multiple wastewater treatment plants in Florida have applied for approval with the Florida Department of Environmental Protection for using our sensor for compliance reporting. Orlando, Florida, is the first city to gain DEP approval. Other municipalities will soon receive these same approvals from the Florida DEP, at which point Halogen Systems Inc. equipment will replace their old technology. “This enables much tighter control of the plant process, with less labor, more reliability, tighter accuracy, and less chemical usage,” says Jason Erskine of HASK, Inc.
Since this technology does not use membranes or reagents, maintenance requirements for chlorine sensors can go from constant to minimal. Manufacturers of Ballast Water Management Systems (BWMS) and Marine regulators saw immediate benefits. Now the Drinking Water industry is taking note, with both NSF-61 Certification and approval for EPA EPA Method 334.0 compliance reporting.
The Halogen Sensor has been granted 11 patents worldwide and is the only online chlorine sensor with NSF61-level certification. This allows it to be inserted directly into a drinking water pipe without a required waste stream. It can do this because it is the only sensor unaffected by fluctuating flow speed or pressure. The flow-generating technology also means that Halogen’s sensors work just as effectively when suspended or simply placed in a water tank.
Standard Membrane and reagent residual chlorine sensors (such as the Hach CL17) require a waste stream of roughly 69,000 gallons of water per year to obtain their readings. Besides excessive water consumption, the cost of the treated water simply going to waste is, on average, $150 per year per sensor. Some utilities have over 100 analyzers operating with waste streams, resulting in a significant wasteful expense. The waste stream from such old-technology sensors cannot simply be discharged into the environment and so requires the use of additional chemical reagents, typically adding an average of $700 per year per analyzer plus labor.
With NSF61 Certification and no need for waste streams or reagents, Municipal drinking water utilities in Florida, California, and Nevada are already evaluating the sensor for deployment.
