| dc.description.abstract | When excessive nitrogen-containing pollutants are discharged into the environment, it may increase the nitrogen loading of the receiving water body, but also cause eutrophication, and affect human health hazards at the same time. In addition, the government attaches great importance to environmental protection regulations and the maturity of the operation technology of public sewage treatment plants. The discharge water quality control requirements from the original traditional organic pollutants to other nutrients such as ammonia nitrogen and total nitrogen.
Due to the characteristics of ammonia nitrogen and total nitrogen pollution factors, biological treatment procedures are the most common strategy in the public sewage treatment technology. It relies on increasing the amount of aeration, adding additional carbon sources and increasing the return of nitrifying liquid to achieve The water quality standard of the effluent causes a waste of resources and energy, which is an important issue that still needs to be resolved.
According to Construction and Planning Agency Ministry of the Interior ＂Design and Interpretation of Public Sewage Treatment Plants＂. The scope of MLE process design parameters that suitable for domestic water quality in Taiwan still need to be comfirm.MLE process was selected in this study to by conducting a model plant test using the domestic sewage of the Taoyuan North District Water Resources Center. , explore the rationality and elastic space of its design parameters, and compare the denitrification effects under different inrenal ratios of nitrification liquid, and establish the best operating data of the MLE program suitable for local water quality characteristics.
In Stage 1, when the biological system operating in F/MBOD = 0.3 kg BOD/kg MLSS‧day compared with other stages, the removal rate of each water quality has a clear downward trend, so it is not conducive to the actual plant Applications. When the ASRT is 15 days and 20 days and other planning operating conditions are the same, it is found that ASRT = 20 days presents a better total nitrogen removal rate, but also shown more interactively correlated with other operating parameters in the ASRT vs. MLSS operating parameter correlation analysis diagram. It is recommended that the ASRT design value of the MLE program for the design and interpretation of sewage treatment plants should be relaxed from 11~15 days to 11~20 days.
The influence of the reflux ratio of the nitrifying liquid on the removal rate of nitrogen pollutants can be shown when R = 2 the system can achieve the highest total nitrogen removal rate of 74%, which is equal to the theoretical maximum total nitrogen removal rate. The concentration is sufficient to meet the total nitrogen discharge standard of the new public sewage plant in the future ; when R = 1, the total nitrogen concentration of the effluent is about 20.2 mg/L, which meets the total nitrogen discharge standard of the existing public sewage plant in the future; when R = 0.5, the ammonia nitrogen nitrification is found The effect is reduced to 70% and the total nitrogen removal rate is the lowest compared with other stages within the recommended operating range of more than 90%. It is recommended that the reflux ratio of the nitrifying liquid should be operated above 1 to ensure that the ammonia nitrogen can effectively carry out the nitrification reaction. | en_US |