The importance of dewpoint measurement…
in Ozone Generation
Ozone (O₃) acts as a powerful oxidising agent and supports a wide range of industrial and municipal treatment processes, including potable water production, wastewater sterilisation, food and pharmaceutical feedwater treatment and swimming pool disinfection. Many facilities choose ozone instead of chlorine because ozone delivers a higher oxidation potential, avoids harmful chlorinated by‑products and leaves only benign oxygen residuals.
Moisture strongly affects ozone generation efficiency and reliability. Most industrial systems rely on corona discharge (CD), and even small increases in water vapour reduce ozone yield, trigger arcing and encourage nitric acid formation, which accelerates corrosion. Excess moisture shortens equipment life, lowers feed‑gas purity and raises operating costs. Because of these risks, accurate dew point measurement serves as a critical control parameter in ozone generation.
How Ozone is Generated
Industry relies mainly on two generation methods: corona discharge and ultraviolet (UV). Corona discharge dominates because it produces higher ozone concentrations by applying a high‑voltage electrical field to oxygen. UV systems offer much lower yields and usually support only small‑scale applications.
Both methods follow the same fundamental mechanism. The system draws oxygen from ambient air or a concentrated source. It then exposes the oxygen to a high‑voltage electrical field or ultraviolet light. This energy splits stable O₂ molecules into individual oxygen atoms, which rapidly recombine with intact O₂ to form ozone (O₃).
The generated ozone enters the process stream and oxidises contaminants such as bacteria, viruses and odour compounds. After oxidation, the inherently unstable ozone eventually reverts to oxygen (O₂)
Where Ozone Is Used
Ozone plays a vital role in water and wastewater treatment processes that demand consistent, high‑yield generation for effective sterilisation and oxidation. Operators use ozone in municipal drinking water production, food and pharmaceutical water disinfection, swimming pool treatment and wastewater sterilisation before environmental discharge. In every case, dew point directly influences the reliability and efficiency of ozone generation.
Why Dew Point Measurement Is Essential in Ozone Manufacturing
Arcing and Electrical Failure
Corona discharge generators depend on a stable high‑voltage electrical field. When moisture enters the feed gas—whether air or pure oxygen—the gas becomes more conductive. As conductivity rises, the system becomes more prone to arcing between electrodes, dielectric breakdown and physical damage to the discharge chamber. These failures can lead to early generator breakdown and costly downtime.
Formation of Nitric Acid and Corrosion
Moisture enables corona discharge to convert nitrogen in ambient air or low‑purity oxygen into nitrogen oxides. These nitrogen oxides then combine with water vapour and form nitric acid inside the generator. Nitric acid attacks stainless steel, seals, dielectric materials, and electrodes, increases maintenance needs, and shortens the system’s operating life.
Major Reductions in Ozone Production Yield
Feed gas dryness directly impacts ozone output. At −70 °C dew point, a generator delivers full rated performance. When dew point rises to −5 °C, ozone output can drop by 50% even when the generator operates normally. If a generator designed for dry oxygen receives moist air instead, yield can fall to 15–25% of its rated capacity, depending on moisture levels and gas quality. Dew point therefore ranks among the most sensitive operational variables in ozone generation.
Moisture Damage to Oxygen Concentrators
Many ozone systems rely on PSA oxygen concentrators, which use molecular sieve beds to remove nitrogen. These sieves are hygroscopic but when exposed to moisture lose effectiveness over time. Saturated or “flooded” molecular sieve media lose efficiency, leading to a reduction in oxygen purity and a dramatic decrease in ozone output. Moisture exposure also shortens the service life of the concentrator itself. Continuous dew point monitoring protects not only the ozone generator but also the oxygen feed gas system upstream.
How Dew Point Meters Are Used in Ozone Generation
Dew point meters play a critical role in monitoring, protecting and optimising corona discharge ozone systems. Most systems require feed gas dryness between −60 °C and −80 °C. Operators usually install the dew point meter directly downstream of the gas dryer—whether desiccant, PSA, refrigeration or hybrid—to verify moisture levels entering the generator in real time.
These meters send continuous data to PLC or SCADA systems for trending, alarms and automatic interlocks. When dew point drifts outside the acceptable range, the system issues warnings or shuts down the generator to prevent arcing, nitric acid formation or severe yield loss. Operators also rely on portable dew point meters during startup, troubleshooting and routine quality assurance to confirm that feed‑gas dryness meets specification.
Even slight increases in dew point can severely impact ozone generation. Moisture can cut ozone output by 50% or more, create arcing conditions, form corrosive nitric acid, reduce PSA oxygen purity and increase maintenance costs. Dew point meters therefore serve as the first and most important defence against trace moisture—the leading threat to ozone generator performance, longevity and efficiency.
Portable Hygrometers
Inline Analyzers
