What indicators are commonly used in the detection of black and smelly water? Black and smelly water often brings discomfort to people visually and olfactorily. Ordinary people can intuitively feel the characteristics of black and smelly water from the color and taste. However, if you want to treat black and smelly water, you must undergo professional testing to determine the treatment method. So what are the commonly used indicators for black and smelly water detection?
1. Ammonia nitrogen content
Ammonia nitrogen is nitrogen in the form of NH3 and NH4+ in water. It is the first step in the oxidation and decomposition of organic nitrogen compounds. Ammonia nitrogen not only promotes the reproduction of algae in water bodies, but also free NH3 is highly toxic to fish. The concentration that kills fish is between 0.2-2.0 mg/L.
In addition, ammonia is also an important oxygen-consuming substance in sewage. Under the action of nitrifying bacteria, ammonia is oxidized into NO2- and NO3-. The amount of oxygen consumed is called nitrification oxygen demand. Therefore, the more ammonia nitrogen there is, the more serious the pollution is, which accelerates the deterioration of the water body.
2. Total Phosphorus
Phosphorus is a nutrient in feed, a component of feed, and a macro-mineral element necessary for animals. In water, phosphorus is a key element required for algae growth. Excessive phosphorus is the main cause of foul and smelly water, eutrophication of lakes, and red tides in bays. Phosphates can also interfere with the coagulation process in water plants.
3. Dissolved oxygen
Under normal circumstances, the dissolved oxygen in the water is constantly replenished due to the dissolution of oxygen from the air and the photosynthesis of green aquatic plants. However, if there are too many organic pollutants in the water, the aerobic bacteria will consume a large amount of dissolved oxygen in the water, and the dissolved oxygen in the water will be consumed quickly.
4. Turbidity
Suspended matter and colloids such as mud, silt, fine organic matter, inorganic matter, plankton, etc. in water can make the water turbid and present a certain turbidity. Black and smelly water bodies are often seriously polluted by organic matter. In addition, the sludge enters the water phase, making the water body black, and the overall turbidity is high.
5. COD
Water bodies often contain various reducing substances, including various organic matter, nitrite, sulfide, ferrous salt, etc. But the main one is organic matter.
When we use potassium dichromate as an oxidant, the reducing substances (mainly organic matter) in the water can be almost completely oxidized. At this time, the oxygen consumption is called chemical oxygen demand, or COD for short. The larger the chemical oxygen demand COD, the more serious the water pollution by organic matter.
The treatment of black and odorous water bodies is a very important part of improving the human living environment. It is of great significance to promote the solution of water environment problems, accelerate the construction of a beautiful new China, and enhance people's sense of happiness.
