Online water analysers for pure/high purity water - Water and Wastewater - Drinking Water

Pure water and high purity water are crutial factors of production in numerous processees and industries. Depending on the demand it is used as a raw material, auxiliary or operating material. Doing this, it is very important to pay particular attention to the quality of the water, because this is crucial for product quality and safe operation of the production facilities. Therefore, continuous monitoring is essential - from an ecological as well as economic point of view.


Feed water/ boiler feed water is used for the operation of boiler plants. In general, feed water systems supplies steam generators, which drives a turbine and thus, generates electricity. Then, the generated steam condenses in a downstream condenser.

In the case, that there is not enough water in the feed water system, it is feeded with fresh make-up water. Hence, boiler feed water is a mixture of make-up water and condensate return.

Pollutions in water can affect the whole system, e.g. it can lead to deposits, corrosions, frequent blowdowns and a higher consumption of chemicals. To ensure a safe and economic operation of the boiler plant, it is essential to monitor the steam-water-circuit at different points. Especially organic pollutants are dangerous. At a high pressure in the boiler, organics produce acidic products, that can damage the piping or the boiler itself. However, a small pollution can lead to failure of the entire production facility.

A prerequisite for reliable TOC measurements are application-specific instrumentations. LAR's QuickTOCpurity is the TOC analyser for pure water applications, that fulfils the requirements of the application.


In steam-water-cycles feed water is heated up and then, it is feeded to a steam generator - steam is produced. Following, a turbine is driven by the steam and as a result, electricity is generated. Downstream to the turbine, the remaining high-pressure steam or low-pressure steam is used for other production processes. The high-pressure steam embodies thermal energy, that is used to heat transfer to another material flow. Usually, the thermal energy is transferred by heat exchangers. If a leakage arises in the heat exchangers, the condensate would affect the product quality and vice versa.

In the event of a leak, condensate can be polluted by organic contaminants which form under pressure carbonic acid or acidic products. Acidic products and carbon acid lead to increased formation of deposits, foam and corrosion. This shall be avoided.

If the hot steam are not used for further processings, then it is cooled down in a condenser. In that case, the resulting condensate is filled up with fresh make-up water. Then, the mixture is feeded back into the steam-water-cycle.

Online TOC analysers provides the fast determination of pollutants in steam and condensate. In the case of a pollution, contaminated water can be drained off. However, clean water shall not be drained off. In addition, the processing of raw water to pure water is very costly and power-consuming. Therefore, the detection of a shock load is just as important as their degradation. Otherwise, expensive, clean condensate is drained off.

LAR's QuickTOCcondensate is an application-specific TOC analyser, that is designed specifically for this application. Thus, even samples with up to 90°C can be measured easily and safely.


In the pharmaceutical industry pure water is used for various production processes. In that case, a distinction is made in Purified Water (PW / Aqua Purificata), Highly Purified Water (HPW / Aqua Valde Purificata) and Water for Injection (WFI / Aqua Ad Iniectabilia). For example, these pharmaceutical water differ with respect to their concentration of conductivity or TOC content.

The monitoring of total organic carbon (TOC) is standardized in international regulations, such as the United States Pharmacopeia (USP), the European Pharmacopoeia (EP). The TOC limit is defined at 500 ppb C.

Mainly, TOC analysers are used to monitor the pure water preparation, the distribution system itself as well as the sampling points. LAR's QuickTOCpharma is the online TOC analyser for the pharmaceutical industry, as it meets the demands of the industry. For instance it is equipped with a software according to FDA 21 CRF Part 11. Furthermore, it provides the monitoring of two sample streams, which enables the monitoring of the inlet as well as the outlet of the pharmaceutical pure water cycle.