# Research Status and Development Trend of Wastewater Treatment Technology and Its Low Carbonization
## 3 Low-Carbon Sewage Treatment Technology
### Research Status  
#### 3.1.1 Resource Recovery Carbon Conversion and Reuse  
In the process of sewage treatment, there are many resources that may be neglected and not fully utilized, for example, some of the energy and heat lost, the transfer of pollutants and the existing sludge. In fact, these can be converted into carbon to achieve recycling. \begin{table}
\begin{tabular}{c c c c} \hline
**Low-Carbon** & **Low Carbonization** & **Concrete Measure** & **Low-Carbon Achievement** \\
**Operation Mode** & **Pathway** & & \\ \hline \multirow{6}{*}{Resource recycling carbon conversion and reuse} & \multirow{2}{*}{Energy-carrying gas} & After the sewage treatment is up to standard, it will be used for factory reuse. & \\  & & Energy-carrying gases such as CH4 and H2 are used for fuel. & \\  & & Heat generated by microorganisms during sewage treatment is used for heating. & \\  & & & \\ \cline{2-4}  & & & Recovery disposal sludge is used in a burning capacity. & \\ \hline \multirow{6}{*}{Comprehens treatment and carbon sequestration} & \multirow{2}{*}{Development and utilization of carbon sequestration} & According to the nature of wastewater, the appropriate treatment process can be selected to reduce the energy consumption such as aeration. & \\  & & & Upgrade equipment such as old blowers or mixers. & \\ \cline{2-4}  & & & Actively develop and utilize new sewage treatment microorganisms to reduce energy consumption and carbon footprints. & \\ \cline{2-4}  & & & carbon footprints in reducing energy consumption and carbon sequestration methods. & \\ \hline \multirow{6}{*}{Operation parameter optimization and process improvement} & Operation parameter optimization & Intelligent parameter control is carried out for each processing unit. & Under the premise of ensuring the standard of sewage treatment, the operation parameters of each treatment unit should be controlled, so as to achieve the standard of sewage treatment with the lowest energy consumption possible of each physical unit. & \\ \cline{2-4}  & & & consumption consumption possible of each physical unit. & \\ \cline{2-4}  & & & treatment process of each treatment unit should be updated in time, and the sewage treatment should be completed according to the concepts of sustainable development and low-carbon treatment. & \\ \cline{2-4}  & & & development and low-carbon treatment. & \\ \hline \end{tabular}
\end{table} 
Table 2: Discussion and summary of low-carbon operation modes in the sewage treatment process. After treatment, those that can reach the standard of reuse can be reused in the factory for greening irrigation, washing or industrial cooling water and other methods of recycling, which is conducive to the dual carbon goal. The chemical and heat energy, and other energy resources generated in the sewage treatment process, may be directly consumed or discharged in the traditional treatment process without effective use, resulting in a great waste of resources. The heat energy may be relatively small, but it could still be put to effective use. [PERSON] et al. [68] prepared materials for CO2 adsorption by activating the residual sludge generated during sewage treatment. After many tests, the adsorption capacity of the material was 11.87 cm 3/g, the separation efficiency was high, and the CO2 recovery rates were 99.68 and 98.11%, respectively. Studies [69; 70], have shown that the heat energy can be recycled through water source heat pump technology and used for heating the sewage treatment plant or surrounding facilities, which can more fully utilize energy resources, reduce carbon emissions, and realize the low-carbon potential of the sewage treatment plant. In addition, in sewage treatment plants with biological sewage treatment, the sludge discharged often contains many substances such as nitrogen and phosphorus converted from sewage. These resources can also be reused to reduce the use of new carbon, to achieve the purpose of relatively low carbonization.