How WWTPs Can Get Greener Grass on the Other Side of the IIoT

By: Stephen Horne

The next big thing is here and it’s the Industrial Internet of Things (IIoT). With pundits waxing philosophical on this big breakthrough, it’s hard to cut through the noise and understand what the IIoT actually is and how it applies to individual plants. I offer the following as a definition. The IIoT means collecting, interpreting, and applying data to actively improve processes or operations. To understand how the IIoT applies to a wastewater treatment plant, look no further than your front yard.

Keeping grass watered is one of the keys to a rich, green yard and there are several ways to accomplish this. The first being Mother Nature—simply letting the lawn absorb whatever rain may fall from the sky. While this may be the easiest option, it’s also the most unreliable. Our next option is to install simple sprinklers. They are slightly better than rainfall, since you can control when they are on and off. But, there’s always too much or too little water and the water isn’t applied evenly. A step up from a sprinkler would be installing an irrigation system with a timer. This offers improvement, but the lawn is watered based on time rather than need. The next level of lawn care uses an app to tie into the irrigation system. It monitors the weather patterns and local temperature, watering the lawn based on collected data. Taking it a step further, you can divide your lawn into separate zones (shade, no shade, flower beds) and specify which ones need more water. The app then factors this data into the plan, giving you the greenest grass on the block.

In a wastewater treatment plant, there are a number of considerations, e.g., reliability, scalability, energy efficiency, maintaining consistent levels of dissolved oxygen (DO). There’s far too much at stake to simply turn on the aeration system, walk away, and hope for the best. And while plants monitor biological activity, many make adjustments manually, leaving much room for error and accuracy. And with IIoT technology, it’s not necessary.

In order for WWTPs to bring the IIoT to their aeration processes, having complete blower packages with integrated controls is the first step. These smart machines monitor the individual unit’s health. With sensors, they track temperature, pressure, oil, and more. Based on this data, they signal if, for example, maintenance is due. Or, in extreme cases, shut the unit down to prevent damage. Smart machines also keep track of load hours, kilowatt usage, and specific performance (wire-to-air efficiency). But simply collecting this data means nothing unless you have the means to gather it from all of the smart machines and then interpret it. In our lawn care example, you can measure the temperature outside yourself and keep a log of the readings, but for a more accurate forecast, you need to consult a meteorologist who can run simulations based on historical data, current conditions, and weather patterns.

This is the interpreting part of the IIoT and it’s accomplished by using a system master controller. The master controller connects each of the smart machines into an aeration network. It monitors all of the data collected by the units, interprets it, and based on the plant demand supplied by the SCADA, selects the right combination of units to meet the demand. Over time, an adaptive master controller improves its understanding of the system by integrating historical data into its algorithm to better predict future demand. Adaptive rather than reactive, it works tirelessly to reduce wasted energy while ensuring a continual supply of air to meet process demand. This eliminates the need for WWTP operators to manually adjust the output flow of the blowers to accommodate fluctuating plant demand.

The most exciting part of the IIoT is the application aspect as the potential here is limitless. For a wastewater treatment plant, this means transferring the system data that has been collected, interpreted, and applied by the master controller to digital devices for convenient viewing. This man-machine connection enables trend analysis: do DO levels begin to fall at certain parts of the day, week, or year? Does demand for aeration air vary seasonally? What is the correlation between temperature increase and lower system efficiency? Having this data at your fingertips empowers making system improvements based on fact rather than assumption. It takes the guesswork out of justifying expenses to accommodate increased demand. Taking the steps to make the changes improves anything and everything from efficiency to reliability.

With all of the IIoT hype, it’s easy to get caught up in the excitement. And while I truly believe that applying IIoT technology can improve operations by reducing downtime and improving energy efficiency, it’s also important to recognize that some wastewater treatment plants may not be ready or, due to size, may not have a feasible ROI for adding smart machines. Take the time to speak with a complete solutions provider who can work with you to assess your current aeration system, discuss your needs and goals, and make solid recommendations for how to proceed.

If you’re interested in learning more about Kaeser’s core technology for the IIoT/Industry 4.0 or want help assessing your current system, contact us.