At present many COD online test, analysis principle is the potassium dichromate oxidation method, chemical reagents need to consume more, such as sulfuric acid, potassium sulfate, mercury, silver sulfate, waste containing acid, chromium, mercury, silver, strong corrosive, and there are two pollution problems, if these don't waste recycling, directly into the environment, causing serious environmental problems, strong acid substances must undergo neutralization after treatment at discharge, waste chromium, mercury and other heavy metals need special treatment!
The COD reagent is consumed by the oxidant water treatment agent which is reducing substances represent an index of water reducing substances in water and how much is organic salt but mainly ferrous sulfide and nitrite are organic compounds by COD reagent and the chemical oxygen demand index is often used as measure of organic matter content in the water much more the water is polluted by organic matter more serious fast with strong oxidation in a certain condition. Fast digestion spectrophotometric method for the determination of COD in wastewater is a kind of fast and efficient analytical method, respectively, in industrial wastewater by COD digestion instrument test special agent and homemade reagent. The results showed that in the range of COD 40~1200 mg/L, the linear relationship between the two reagents was almost the same, and the correlation coefficients reached 1, which also had good precision and accuracy.
Chemical oxygen demand (CODCr) is a routine monitoring item in water quality monitoring. It reflects the degree of pollution of reducing substances in water, and is one of the important indicators of total emission control in China. At present, the COD project for daily import and export of water from the Jiangnan wastewater treatment plant is detected by the method of spectrophotometric method. The instrument used is the COD measuring instrument of HACH company in the United States. Although the HACH reagent method using a small amount, but also reduce the operation trouble, but the price of expensive COD special reagent for supporting, such as sewage treatment plants the primary laboratory of long-term use, will bring the detection cost increases, will also cause some waste of resources and costs. To this end, we studied according to the CODCr principle and the determination of the actual situation, prepared by the COD reagent using existing instruments and reagents, experiments show that the COD reagent meets the detection requirements, thus greatly reduce the detection cost, simplify the procurement cycle is long for reagent control the actual work brought to.