1. Wastewater Quality The water quality of domestic sewage is usually relatively stable, the general treatment methods include acidification, aerobic biological treatment, disinfection and so on. And industrial wastewater should be based on the specific water quality situation of the reasonable choice of process.
In particular, it should be noted that for the use of aerobic biological treatment process wastewater treatment, attention should be paid to the biochemical nature of wastewater, usually requires COD/BOD5>0.3, if not meet the requirements, can consider anaerobic biological hydrolysis acidification, in order to improve the biochemical nature of wastewater, or consider the use of non-biological treatment of physical or chemical methods.
2. degree of sewage treatment This is the main basis for the selection of sewage treatment process. The degree of sewage treatment depends in principle on the water quality characteristics of the sewage, the whereabouts of the treated water and the self-purification capacity of the sewage into the water body. However, at present, the determination of sewage treatment degree mainly complies with the relevant legal system and technical policy requirements of the State. In general, environmental management controls the concentration of sewage emissions in accordance with the comprehensive sewage discharge standards and related industry emission standards, and some areas with high levels of economic development also impose stricter local emission standards. Therefore, no matter what kind of sewage needs to be treated, and regardless of the treatment process and degree of treatment, should be based on the treatment system effluent can meet the standards of the basis and premise.
Prevent and control environmental pollution of water bodies in accordance with the requirements of laws, regulations and policies.
3. Construction and operating costs When considering the construction and operation cost, we should take the treatment of water to meet the water quality standard as the precondition. Under this premise, the process of engineering construction and low operating cost should be paid attention to.In addition, reducing floor space is an important measure to reduce construction costs.
4. Ease of construction of the project The difficulty degree of engineering construction is also one of the influencing factors of selecting process flow.
If the groundwater level is high and the geological conditions are poor, it is not suitable to choose the treatment structure with large depth and high construction difficulty.
5. Natural and social conditions on the ground Local topography, climate and other natural conditions also have a certain impact on the choice of wastewater treatment process. If the local climate is cold, it should be used after the adoption of appropriate technical measures, in the low temperature season can also be normal operation, and to ensure the achievement of the standard water quality process.
Local social conditions, such as raw materials, water resources and electricity supply, are also among the factors that should be taken into account in process selection.
6. Water quantity of sewage In addition to water quality, the amount of sewage is also one of the influencing factors.
For sewage with large changes in water quantity and water quality, it is first considered to adopt a process with strong impact-resistant load capacity, or to consider the establishment of cushioning equipment such as regulating ponds to minimize adverse effects.
7. Does the process create new contradictions The sewage treatment process should pay attention to whether it will cause two pollution problems. For example, pharmaceutical plant wastewater contains a large number of organic substances (such as benzene, toluene, bromine, etc.), in the aeration process will have organic exhaust emissions, the impact on the surrounding atmospheric environment, fertilizer plant gas wastewater in the use of precipitation, cooling treatment after recycling, in the cooling tower exhaust gas will contain cyanide, pollution to the atmosphere; Pesticide plant lotus Fruit Wastewater Treatment , The alkaline method to degrade the lotus fruit, such as the use of lime as alkaline agent, the resulting sludge will cause two pollution, printing and dyeing or dye plant wastewater treatment, sludge disposal as a key consideration. In a word, the choice of sewage treatment process should take into account various factors, and carry out the technical and economic comparison of various schemes in order to draw conclusions.