Alert on water quality
Whether it is process water, drinking water, surface water or (industrial) waste water, many applications are available for Metrohm Applikon online analyzers. The modular concept of the analyzers makes it possible to adapt the configuration of many of our analyzers to specific applications or process circumstances. Our range of ALERT analyzers is dedicated to the analysis of substances in water. This ranges from Ammonia and Phenol in Waste Water and Surface Water (with a colorimetric method), to Iron in Drinking Water and Sodium, Silica and Hydrazine in Ultra Pure Water for the power industry. A complete overview of Applications for the ALERT series can be downloaded here. The number in the table is the number of the Application Data Sheet that can be obtained from your local distributor.
Water applications
For the more demanding applications in water, Metrohm Applikon has the 201Y range of Analyzers as well as the 2045TI multi purpose analyzer and the 2045VA analyzer. The latter is specifically meant for heavy metal analysis in for example Surface Water. With the 201Y and the 2045TI a wide range of applications can be covered, ranging from peracetic acid analysis for the bottling industry with the 2018 Stainless Steel Analyzer to COD analysis with the 2019 or the 2045TI, to Alkalinity measurements for the Brewing Industry with the 2045TI. All applications that are possible with a 201Y analyzer can also be done with a 2045TI, but then also in multi-stream and multi-component version. A complete overview of all possible applications with these analyzers can be downloaded and some typical examples are given below.
Low level sodium
Typical water treatment plants use ion exchange resins to remove unwanted inorganic compounds. Anion resins remove anion species such as carbonate. Cation resins remove cations such as sodium. Sodium is the first cation that breaks through when the resin is exhausted. Measurement of the sodium level allows regeneration of the resin as required rather than by volume and/or time. This ensures that the water quality is always maintained, minimizes regenerant costs and can prevent corrosion due to the presence of cations. Although laboratory analysis forms a part of the normal quality control process it can require high demands of manpower and, by its nature, can only provide information for a specific point of time. Therefore online monitoring is preferred. Sodium levels can be monitored online with an ALERT or ADI2018 analyzers, using a Na-ISE.
Ammonia in drinking, waste or cooling water
As stated in a WHO report on drinking water: “The presence of elevated ammonia levels in raw water may interfere with the operation of manganese-removal filters because too much oxygen is consumed by nitrification, resulting in mouldy, earthy-tasting water. The presence of the ammonium cation in raw water may result in drinking-water containing nitrite as the result of catalytic action or the accidental colonization of filters by ammonium-oxidizing bacteria” The analysis of Ammonia with ALERTs can be done either colorimetrically or with ion selective electrodes, depending on the desired detection range and limits. Manganese and nitrite mentioned above can also be measured with an ALERT analyzer.
COD
The chemical oxygen demand (COD) test is commonly used to indirectly measure the amount of organic compounds in water. Most applications of COD determine the amount of organic pollutants found in surface water (e.g. lakes and rivers), making COD a useful measure of water quality. COD is measured in mg/l through a colorimetric method in which dichromate is added and the sample is digested. Depending on the concentration range a ADI2019 or an ADI2045TI needs to be used.
