Smart moisture measurement technology continually optimizes process quality

For chemical processors involved with powders, pellets, blocks, chips, liquids, slurries, minerals in concentrates, and sludges, advances in smart moisture measurement can help continually optimize process quality as well as product.

In a world full of smart devices (i.e., smartphones, smart watches and smart appliances), such technology is increasingly entering processing and manufacturing in forms like condition monitoring, advanced robotics and industrial IoT.

For chemical processing, “smart” equates with the ability to continually monitor conditions such as product and input moisture content in real time to optimize quality. Assessing proper moisture level in processes and products is essential for many reasons such as meeting regulatory standards, ensuring proper chemical reactions and drying, maximizing shelf life, and increasing selling price and decreasing shipping cost.

“Whether chemical processors are mixing, blending, homogenizing or drying, non-contact, smart inline technology enables the rapid, automatic measuring of moisture in 100% of product or inputs, along with the ability to instantly fine-tune the process," said John Bogart, managing director of Kett US, a manufacturer of a full range of moisture and organic composition analyzers. "This can optimize quality as well as minimize waste and corrective re-processing.” 

According to Bogart, the technology is smart because all the calculations are performed inside the sensor and measurements are sent on a 24/7 basis to smartphones, PCs and other devices without having to be connected. If desired, these instruments can prompt operators and managers with alerts as needed. He notes that smart technology enables taking multiple precise moisture measurements each second, sorted within integrated software. This enables not only real-time analysis and error detection but also more accurate results in processes and products subject to variable, fast-changing conditions.

Continuous moisture monitoring by such smart technology also allows the tracking of historical performance trends, cyclical rhythms and periodic failures, so corrective adjustments can be made to enhance production. Such capability also provides process quality and compliance documentation when required.

Breaking from conventional limitations

For chemical processors, unleashing the full potential of smart process technology in terms of moisture measurement, however, is not possible using traditional techniques. Conventional testing methods that require time-consuming weighing and drying are often too time and labor-intensive to be practical, and laboratory testing faces the same drawbacks.

“With typical testing, by the time results come back from the lab, any off-spec product can already be processed, packaged and shipped. If chemical processors are not measuring in real-time, inevitably there will be some variation in inputs, process and quality,” says Bogart.

Traditional data collection, in fact, is usually too slow, cumbersome and chained to cords and cables. Production floors are already crowded with equipment. So, dealing with bulky cords and connections to PCs, keypads and external switches to transfer data can be too restrictive.

“Fitting inline testing equipment into space-restricted production lines can be difficult when wires, cables, etc., must be run to a variety of peripheral instruments. In such cases, the cost of labor, installation and system integration can be as much as the device itself,” said Bogart.

In response, for chemical processors industry innovation has developed smart inline technology that can rapidly measure moisture in samples multiple times per second. The approach utilizes near-infrared (NIR) light in a highly accurate, non-contact secondary measurement method that can deliver immediate, laboratory quality moisture readings without the labor, cost or delay of conventional techniques.

According to Bogart, NIR moisture meters allow very accurate instant measurement of solids and liquids without contact or sample preparation, so there is no contamination, who notes that this extends to chemicals in all forms (i.e., powders, pellets, blocks, chips, liquids and slurries) as well as minerals in various forms (i.e., powders, pellets, concentrates and sludges).

Once the meter has been calibrated against the lab or production standard, the calibration is stored in the device so no additional calibration work is required, and measurements are fully traceable to the original measurement method. Because the process is non-destructive, samples remain unaltered so they can be used for additional tests or put back into the product stream.

“NIR moisture and organic composition meters follow the principle that water and other organics absorb certain wavelengths of light,” said  Bogart. “The meter reflects light off the sample, measures how much light has been absorbed, and the result is automatically converted into a moisture (or organic component) content reading.”