In order to provide continuous and stable water resources, water recycling has been rapidly developed within the scope. This is usually due to water scarcity, water pollution, or the development of water recycling technologies to exploit available water resources. In some areas of wastewater collection systems in developed countries, water reuse is also increasingly taking into account environmental and public health factors. Despite this, in many countries there are no sewerage systems and sewage heavy systems, and untreated and partially treated wastewater often serves as an important source of water and nutrients. For countries in arid areas, waste water cannot be wasted and must be further used, and with public health and environmental concerns, waste water is also recycled. Let's talk about the three major roles of submersible mixers in sewage treatment!
1. Promote hydraulic circulation
Hydraulic circulation with submersible mixer is a means of energy saving, especially in anaerobic tank, anoxic tank and oxidation ditch of sewage biochemical treatment. Since only loops need to be provided in this type of pool; The flow rate can keep the mixed liquid in the pool in a suspended state, so that the microorganisms are in full contact with their substrate, so the pool shape is mostly shaped by oxidation ditch, and the energy input by the submersible mixer forms a continuous circulating water flow. This design can not only keep the mixed liquid suspended, but also because the flow rate of circulating water in the pool is usually tens of times higher than the inflow flow, or even hundreds of times, so that the pool flow has a huge dilution homogenization capacity, so that the process has the characteristics of impact load resistance.
Also in the oxidation ditch design, the surface aeration equipment has the dual functions of oxygenation and hydraulic circulation. In the engineering, it is often necessary to adjust the oxygen capacity due to the change of water quality and water quantity, and it is difficult to take into account the circulation velocity in the pool, resulting in the problem of sediment accumulation in the ditch, and the addition of the submersible mixer can solve the problem of sediment accumulation, and the technical transformation is not complicated, and the investment is very little.
2. Improve oxygen transfer efficiency
In the sewage biochemical treatment system, aeration is the basic means to maintain the normal metabolism of aerobic microorganisms, and the oxygen transfer efficiency of the underwater aeration system is directly related to the water depth. In the aeration pool, the submersible mixer is used to design the aeration pool into the continuous circulation flow pool, which will change the path of releasing bubbles from the aeration head under the action of circulation flow rate, increase the oxygen transfer water depth and improve the oxygen transfer efficiency. With this design, the oxygen transfer efficiency of the aeration system can be improved by about 15%, and the energy consumption and operation cost of sewage treatment can be saved.
3. Mixing and stirring
With the development of biochemical treatment technology of sewage, the process of segmental and segmented treatment has appeared. However, the single cell pool capacity is small, each cell can be designed to fry rice cake square plane or circular plane, and a stirrer is set in each cell. The arrangement of such reactors is very flexible, and can be placed anywhere in the circular pool, if the thrust generated is in the same direction as the water flow. In the rectangular pool, it should be arranged at the corner of the pool wall, and the choice of water flow direction should be paid attention to in the design. When the volume of a single tank is large, the technical plan should be analyzed and compared to choose whether to use stirring type or propellant type equipment. Generally speaking, the larger the pool capacity and surface of a single pool, the more economical the use of propellant-type equipment. In summary, the social, economic and environmental impacts of past water resource exploitation and the inevitable scarcity of water resources have led to a search for new ways of managing resources in China. New contemporary management approaches incorporate sustainability principles, environmental ethics, and public participation in project development. As a result, submersible mixers in water recycling and reuse have become an attractive option to protect and increase water supply.