News

TOC, COD and TN analysis with high salt concentrations

Numerous processes within industry are characterized by high salt concentrations in water. In order to enable reliable monitoring, LAR Process Analysers AG developed an outstanding High Salt Option for their online water quality analyzers.

TOC, COD and TN analysis with high salt concentrations

LAR's high salt option enables the reliable measurement of water samples with up to 30% salt concentration

Numerous processes within industry are characterized by high salt concentrations in water. In order to enable reliable monitoring, measurement technology is required, that is designed for the measurement of water samples with high salt concentrations.

LAR Process Analysers AG, Germany, developed an outstanding High Salt Option for their online water quality analyzers. Now, samples with salt concentrations of up to 300 g/l NaCl (30%) can easily be measured. The analyzers QuickTOCultra, QuickCODultra and QuickTONultra are for the measurement of total organic carbon (TOC), chemical oxygen demand (COD) and total nitrogen bound (TNb) in water. LAR's high salt option is based on the ultra-high-temperature combustion at 1,200 °C. At this high temperature salts are completely melted and led out of the oven in fluid form by the condensate. Sample pretreatment or dilution is not necessary. Downstream of the oven, the melted salts are collected in a special designed reactor foot, from which they can be easily disposed of. As a result, blockages and defective reactors belong to the past. Through the special process management and optimized reactor construction of LAR's High Salt Option long downtimes and high following costs are minimized.

At a Glance:

  • Long-life reactor
  • Clog-free
  • No dilution of samples

The total organic carbon (TOC) is one of the most important sum parameters in the assessment of the organic pollution of water. Since it includes all carbon compounds as one mass, it is exactly defined and an absolute quantity. Therefore, it may be determined directly.

Read more about TOC measurement methods.

Total organic carbon analyzers of LAR Process Analysers AG

The chemical oxygen demand (COD) indicates the amount of oxygen which is needed for the oxidation of all organic substances in water and is thus an important indicator for water analysis. It is considered in the planning and controlling of treatment, as well as assessing its efficiency, thus forming the basis for the calculation of waste water charges.

The COD can be determined in laboratory or online, whereby these methods significantly differ in duration and consumables used.

Read more about COD measurement methods.

COD analyzers of LAR Process Analysers AG

The biochemical oxygen demand (BOD) indicates the amount of oxygen which is needed for the biological degradation of organic substances in water.

Since the generally used BOD5 excludes the nitrification part of the process, this parameter is poorly suited for the control of waste water treatment plants. Alternatively, the total BOD is well-suited, due to the determination of the nitrogen as well as the carbonaceous part of biological degradation.

Read more about the online measurement of BOD.

Toxicity is described as the direct harmful effect of a substance on organisms. These effects can already occur at low concentraions of toxic substances and are dependent on the incubation period and the dosage.

Some test methods that are available on the market can detect toxicity by using fish, daphnia, molluscs, algae or luminous bacteria and testing whether a water sample has a toxic effect on the organisms. They do not, however, identify exactly which toxins are present.

Read more about online toxicity measurements.

BOD / toxicity analyzers of LAR Process Analysers AG

The total nitrogen bound (TNb) shows the pollution of water caused by nitrogen compounds. Nitrogen may be present as ammonia, ammonium salts, nitrites, nitrates and organic nitrogen compounds.

In contrast to single measurements of the above-mentioned components, the TNb determination contains all these substances in a single analysis process.

Read more about online TNb measurements.

The total phosphorus (TP) is a sum parameter that shows the organic and inorganic phosphorus compounds in water. Phosphorus is an essential nutrient for humans as well as flora and fauna. However, the substance – depending on its concentration– may cause serious damage.

Read more about online TP measurements.

TN TP analyzer of LAR Process Analysers AG