Detailed explanation of nitrogen and phosphorus removal technology for low-carbon source wastewater

With the acceleration of urbanization and economic development in China, the problem of sewage treatment is becoming increasingly prominent. The high nitrogen and phosphorus content in low-carbon source wastewater poses great challenges to wastewater treatment. In order to solve this problem, a series of nitrogen and phosphorus removal technologies have emerged. This article will provide a detailed introduction to the nitrogen and phosphorus removal technology for low-carbon source wastewater, aiming to provide reference for related research and application.
1、 Technical Overview
Low carbon source wastewater denitrification and phosphorus removal technology refers to a series of biological and chemical methods used to remove nitrogen and phosphorus from wastewater during the treatment of low-carbon source wastewater, in order to meet discharge standards or reuse requirements. These technologies are mainly based on the nitrification denitrification, adsorption and other functions of microorganisms, and improve the removal efficiency of nitrogen and phosphorus by regulating reaction conditions reasonably.
2、 Main technical means
1. Additional carbon source
In low-carbon source wastewater, the available organic carbon sources are limited, so it is often necessary to add additional carbon sources to meet the growth needs of microorganisms. Commonly used external carbon sources include methanol, acetic acid, glucose, etc. These carbon sources are utilized in the denitrification process, converting nitrogen in wastewater into nitrogen through nitrification denitrification, thereby achieving the goal of denitrification.
2. Optimize the water inlet method
Optimizing the inflow method is achieved by changing the direction or distribution of wastewater, improving the utilization efficiency of organic carbon sources and the removal efficiency of nitrogen and phosphorus. For example, the segmented inflow process can distribute organic matter in different reaction zones, improving denitrification efficiency; Periodic changes in the direction of inflow can promote the contact between organic matter and microorganisms in wastewater, improving the removal efficiency.
3. Cancel septic tanks
Traditional septic tanks have limited effectiveness in removing organic matter and can easily lead to the loss of carbon sources. After canceling the septic tank, the raw sewage can be directly sent to the sewage treatment plant for treatment, improving the utilization rate of organic carbon sources and reducing the loss of carbon sources.
4. Phosphorus recovery
Phosphorus is another important element in wastewater treatment. Recycling phosphorus resources can not only reduce the pollution of phosphorus to the environment, but also be used for agricultural production or other industrial purposes. The commonly used methods for phosphorus recovery include chemical precipitation, crystallization, adsorption, etc. Through these methods, phosphate can be extracted from wastewater and further processed and utilized.
3、 New technological progress
With the continuous progress of technology, some new nitrogen and phosphorus removal technologies have gradually emerged:
1. Synchronous nitrification denitrification: This technology refers to the simultaneous nitrification and denitrification processes in the same reactor. By controlling reaction conditions such as aeration rate and reaction temperature, the growth and metabolism of nitrifying and denitrifying bacteria are promoted, thereby improving denitrification efficiency. This technology can reduce carbon source addition and aeration, and lower energy consumption and costs.
2. Anaerobic ammonia oxidation: Anaerobic ammonia oxidation refers to the biological reaction process of oxidizing ammonia to nitrogen under anaerobic conditions using nitrate as an electron acceptor. This technology can significantly reduce energy consumption and carbon source addition, improving denitrification efficiency. However, the growth and metabolic conditions of anaerobic ammonia oxidizing bacteria are relatively strict, and further research and optimization of reaction conditions are needed.
3. Biological phosphorus removal: Biological phosphorus removal refers to the use of phosphorus accumulating bacteria to absorb and release phosphorus under aerobic and anaerobic conditions, achieving phosphorus removal through repeated processes of phosphorus absorption and release. This technology can reduce the dosage of chemical agents, lower treatment costs, and reduce secondary pollution. The research and application of biological phosphorus removal technology still require continuous exploration and practice.
4. Short range nitrification denitrification: Short range nitrification denitrification refers to controlling the nitrification process in the nitrite stage, and then conducting denitrification reactions to directly convert nitrogen into nitrogen. This technology can reduce aeration, carbon source addition, and energy consumption costs, and improve denitrification efficiency. However, the control conditions for short-range nitrification and denitrification are relatively strict, and further research and optimization of reaction conditions are needed.
4、 Conclusion and Outlook
Low carbon source wastewater denitrification and phosphorus removal technology is one of the important research directions in the current field of wastewater treatment. Through continuous exploration and practice, we are expected to find more efficient and environmentally friendly sewage treatment methods. Meanwhile, with the continuous emergence and application of new technologies, we should also strengthen technological research and innovation, and promote the further development of low-carbon source wastewater denitrification and phosphorus removal technology.