The process of eliminating traces of organic matter using ultraviolet rays is what we refer to as Oxidation with ultraviolet light. It is possible to use a UV lamp that emits 185 nm radiation to cause a photo-oxidation effect. This radiation level causes the oxygen present in the water to transform into ozone, triggering an activity that oxidizes organic matter down to CO2.
The measurement of organic (carbon-based) pollutants in a water system is described by the Total organic carbon (TOC). We can see the effect of organic pollution from various natural sources such as alcohol, sucrose, PV cement, Sugar, plastic-based derivatives, etc. All these contribute to the increase in organic pollution.
It is generally difficult to detect nonionic organic contaminants using standard measurements of conductivity. This is why we hardly recognize the high level of Total organic carbon using low conductivity and high resistivity in an ultrapure water system.
High TOC levels can do the following:
- Cause a degradation in purification systems.
- Limit the yields of a semiconductor.
- Increase contamination in pharmaceutical products.
- Damage steam and power generation equipment.
It is essential to monitor the TOC levels using TOC monitors and control systems to evaluate the quality of various water purification processes. Many industries make use of quality technological gadgets for this purpose. We can see the use of this technology in the Semiconductor industry Pharmaceutical/ food processing industry and also in the Power generation.
In this type of production, it is essential to reduce the TOC level, and therefore UV lamps or UVC tubes (หลอด uvc which is the term in Thai) with wavelengths of 185 nm are used.
It is also more common to use ultraviolet light in advanced oxidation processes to break down very stable and difficult to decompose substances. In advanced oxidation processes with 185 nm UV, oxidants such as hydrogen peroxide are added to the water exposed to 185 nm UV rays, generating the formation of incredibly oxidizing hydroxyl radicals.