Advantages of on-line analytical instrument for UV254 ultraviolet spectrometry

    Now the water quality analysis industry is more and more hot, and there are many domestic and foreign analytical instrument manufacturers. In fact, at present, no matter domestic or imported analytical instruments, there are only several common analytical principles, such as colorimetry, UV254 ultraviolet spectrometry, membrane amperometric polarography, etc.

   These are the most commonly used detection principles. Colorimetry requires reagents, but the reagents in the later period of 3S in Italy are very low, and the maintenance cost is low. UV254 UV spectrometry does not need any reagents, and the maintenance cost will be lower, but it can only detect a few parameters, such as COD / BOD / NOx / turbidity / chroma / TOC. Next, Anhui purple core semiconductor technology Co., Ltd. takes the Italian 3S brand COD online analyzer as an example to introduce the working principle of the Italian 3S UV UV254 online analyzer

    The instrument adopts ultraviolet spectrum method; When organic compounds containing conjugated double bonds or polycyclic aromatic hydrocarbons are dissolved in water, they can absorb ultraviolet light. Therefore, by measuring the absorption degree of these organic compounds to 254 nm ultraviolet light, the measurement results are expressed by the special absorption coefficient sac254, which is used as the physical quantity to measure the total amount of organic pollutants in water. According to beer Lambert's law, the measurement principle is based on the UV absorption of unsaturated organic molecules at 254 nm[ C] = k log (iin / IOUT), [C]: sample concentration; K: The correlation coefficient between UV absorption and COD was linear. I in: incident light intensity, I out: transmitted light intensity. The instrument automatically compensates turbidity, suspended solids and dirt through a dual beam system (another detector is 550nm).