Turbidity testing methods and standards

Some common substances and gases such as chloride ions will appear in the test. Some people may not have heard of what this is. Let’s discuss it today. What is chloride ion? Turbidity detection In a chemical reaction, chlorine atoms gain electrons, thus charging the reacting chlorine atoms. Charged chlorine atoms are called chloride ions. It is the most common anion in water. Excessively high chloride ion content will cause bitter and salty drinking water, soil salinization, pipeline corrosion, difficult plant growth, and endanger human health, so the accuracy of the determination of chloride ion content is very important. Source of chloride ions? The sources of chloride in surface water for turbidity detection are mainly divided into two categories: natural sources and anthropogenic sources. ⑴Natural source: First, the water source flows through the chloride-containing formation, causing salt deposits and other chlorine-containing sediments to dissolve in the water. The second is that the river or river water close to the ocean is affected by the tide and the wind from the sea, which leads to an increase in the chloride content in the water. (2) Man-made sources: mainly industrial wastewater discharged from industries such as mining, petrochemical, food, metallurgy, leather (tanned leather), chemical pharmaceuticals, papermaking, textiles, paints, pigments and machinery manufacturing, and domestic sewage generated by human life , of which industrial emissions are the most important source. Common chloride ion limit standards for turbidity testing (1) Stainless steel pipes: The chlorine ion content of stainless steel pipe test water is mandatory to be less than 50ppm (TSG D0001-2009) and 25ppm (GB 50235-2010) is recommended. When the chloride ion content is greater than 25ppm, stress corrosion, pitting corrosion, and intergranular corrosion will occur in stainless steel. Urea circulating water: The control range of chloride ions is determined by the content of chloride ions in the replenishment water and the cycle times of the water. If the supplementary water chloride ion is 10ppm, and the circulating water is concentrated 3 times, then the circulating water chloride ion should be less than 30ppm. If the chloride ion in the circulating water is greater than 30ppm, it means that the concentration of the circulating water is greater than 3 times, and the system may be fouled. If the chlorine ion in the circulating water is less than 30ppm, it means that the concentration ratio of the circulating water is less than 3 times, resulting in a waste of water resources.