The air flotation machine is mainly used to remove suspended impurities with a density similar to that of water, which cannot settle naturally and are difficult to float up naturally. The air flotation machine has the advantages of high separation efficiency and simple equipment. The air flotation effect is crucial for the quality of effluent water. To achieve good air flotation effect, it is necessary to understand the air flotation machine and comprehensively analyze the factors that affect the changes in effluent quality.
1. The sewage flow is large.
The impact of sewage flow rate on treatment efficiency cannot be ignored. When operating the dissolved air flotation machine, it is necessary to ensure uniform water distribution in each flotation tank. The change in flow rate means a change in the amount of pollutants, so it is necessary to adjust the dosage of reagents in a timely manner to achieve better results.
2. Dissolved gas volume, reflux ratio, and dissolved gas tank pressure.
3. The influence of coagulants and pH on the treatment efficiency of air flotation machines.
Generally speaking, the higher the COD concentration of raw water, the more chemicals need to be added. The higher the concentration of suspended solids in raw water, the greater the dosage of drugs that need to be added. There is a good dosage for the occurrence of flocculation. If the dosage is exceeded, it will have the opposite protective effect. In addition, attention should be paid to the proportion and sequence of administration.
4. Scraping frequency of air flotation machine.
The frequency of scraping is related to the thickness of the floating slag. The thicker the thickness, the lower the moisture content, which may lead to poor fluidity of the sludge, blockage of the sludge discharge pipeline, and high sludge concentration and viscosity in the subsequent sludge tank, making it difficult to improve. Excessive floating slag can lead to an increase in overall density, making it difficult to separate mud and water, and affecting the quality of the effluent. Therefore, the frequency of the scraping air flotation machine should be adjusted according to the amount of floating slag generated.
5. Cleaning of the air flotation system.
Due to the fact that industrial wastewater and sewage generally contain a considerable proportion of Ca2+, and some flotation agents are added during the air flotation process, a layer of scale will adhere to the wheels and bearings of the dissolved air flotation system after running for a period of time, which will reduce the efficiency of the air flotation system. Therefore, the air flotation inclined plate and release device should be cleaned regularly. At the same time, check whether the release device is intact, whether there is corrosion, leakage, or blockage.